José Laranjo - Academia.edu (original) (raw)

Papers by José Laranjo

O ColUTAD é um castanheiro híbrido, resultante do cruzamento entre o castanheiro europeu (Castane... more O ColUTAD é um castanheiro híbrido, resultante do cruzamento entre o castanheiro europeu (Castanea sativa) e o castanheiro japonês (Castanea crenata). Este clone, disponível no mercado, tem como principais características o facto de ser considerado bastante resistente à doença da tinta e de poder funcionar como porta-enxerto das variedades tradicionais com vista à resolução de uma das principais doenças do nosso castanheiro potenciada pelas alterações climáticas. Este hibrido apresenta um porte mais ananicante do que o castanheiro europeu permitindo apertar os compassos de plantação e aumentar a produção de castanha nos primeiros anos do souto. Contudo, a produção da castanha é fortemente condicionada pelas condições meteorológicas médias e extremas verificadas durante o seu ciclo anual. Assim, é importante testar a adaptação de novos porta-enxertos e variedades tradicionais de castanha em situações extremas para a espécie face à variabilidade do clima e alterações climáticas futura...

<p>The chestnut trees are well adaptated to... more <p>The chestnut trees are well adaptated to temperate and humid climates, with moderate annual thermal contrast and without long and severe summer droughts. Bioclimatic studies suggest that chestnut trees have special needs, including at least six months with average monthly air temperature above 10 ⁰C, total annual precipitation of 800 – 900 mm, and 25% of annual precipitation in summer. Weather is also determinant in the phenology of the species. For example, the suitable average air temperature range is: 13 – 15⁰C to initiate the phenological activity, 18 – 20⁰C for flowering, and 20 – 22⁰C for maturation. Therefore chestnut production is highly affected by adverse weather conditions and can be severely reduced by the occurrence of extreme weather/climate extremes: late frosts, heat waves, heavy rainfall, wind gusts, maximum air temperature lower than 25⁰C during flowering or above 32⁰C, which cause thermoinhibition of vegetative activity. Thus, it is important to characterize the chestnut producing regions in present and future climate and estimate how, when and where the weather conditions will be maintained or changed. For this study we used meteorological data from ERA5 for the 1981 – 2010 period and several GCM-RCM simulations from CORDEX Bias-adjusted RCM data for 2011 – 2100 period to assess the climate for current and two future scenarios (RCP 4.5 and RCP 8.5). The meteorological variables selected for this study have been identified in previous studies as having the greatest influence in the phenological activity of the chestnut tree and on the chestnut productivity. The results include the identification of the regions where: (i) the variables will have significantly different statistical distributions in the future; (ii) will be necessary to adopt hazard risk management and climate adaptation measures, including substitution by other varieties more adapted to future conditions or the development of genetic improvement programs; and, (iii) the identification of new production areas.</p>

Revista de Ciências Agrárias, 2018

Different types of irrigation systems can be used in chestnut orchards. To understand which one g... more Different types of irrigation systems can be used in chestnut orchards. To understand which one grants higher yield values treatments were applied in adult trees: drip system-TI; micro-sprinkler system-SI; non-irrigated system-NI. The study covers two years in the northeast of Portugal. Irrigation was triggered every time stem water potential was lower than-1.2 MPa. The study considers costs with the equipment, water and labour, and the income from the chestnuts' sale. Due to the hotter conditions of 2016 more water was supplied (93 mm) than in 2015 (47 mm). Little more water was furnished in SI (73 mm) than in TI (67 mm). Production was 27% higher in irrigated (48 kg/tree) than in NI trees (38 kg/tree) and in relation to the canopy's area (kg/m 2) the TI produced 18% and SI 29% more than NI. Annual costs were higher with irrigation (4654, 4549 and 1530 €/ha for SI, TI and NI, respectively) but the higher income (22126, 21984 and 16174 €/ha for TI, SI and NI respectively) made up for the investment. The profits from irrigated trees can be 22% or 37% higher than in non irrigated ones, for 1 ha or 5 ha, respectively.

International Journal of Environment, Agriculture and Biotechnology, 2017

The European chestnut (Castanea sativa Mill.) is a specie with great economic importance in Europ... more The European chestnut (Castanea sativa Mill.) is a specie with great economic importance in Europe that have been present for thousands of years. In Portugal, the chestnut helps to maintain a positive trade balance, by contributing to the gross national product (GDP). One of the biggest threats for the chestnut is the ink disease caused by Phytophthora cinnamomi, this disease is problematic to chestnut crop with a damaging impact. Silicon (Si) is classified as a beneficial nutrient, having the ability to make plants more resistant to attacks by pathogens. Studies on the effect of silicon on chestnut are practically non-existent, so the aim of this study was to evaluate the impact of silicon in the resistance of chestnut plants to P. cinnamomi. The plants were treated by 0 mM, 5 mM, 7.5mM and 10 mM SiK ® with the analyzed mad at 0, 15 and 30 days after inoculation by P. cinnamomi. These findings showed that the Si-treated plants had higher survival rate resulted from the presence of phytoliths in root tissues, that acted as a mechanical barrier reducing the development of pathogenic structures and they arealso associated with the improvement on antioxidant activity through the increase of CAT and SOD, higher values of total phenols compounds and less oxidative damage. The presence of Si in PDA medium reduced the growth of P. cinnamomi all over the time, presenting high PI. This work shows that the Si fertilization in chestnut plants contributes to increase the resistance against P. cinnamomi infection.

CyTA - Journal of Food, 2019

The increasing demand for healthy products rises the pressure on the chestnut production due to t... more The increasing demand for healthy products rises the pressure on the chestnut production due to their nutritional qualities and beneficial health effects. Martaínha chestnut variety is most welladapted with great economic importance due to its precocity and technological properties. The exogenous application of Silicon has an important role in agriculture because of improvement of plants nutrition. Nevertheless, the knowledge of impact of Silicon application in the production, sensory quality and chemical composition of chestnut fruits is limited. The application of Si in leaves (SL) and soil (SS) have important action on the prophylactic properties and the promotion of chestnuts health. Moreover, higher number of healthy fruits, caliber, fruits without rotten and tortrix infection and lower water loss in post-harvest chestnuts, in SL and SS samples, highlights the Si positive action. Additionally this study emphasizes some positive effects of Silicon on the chemical and sensory profile. Producción, composición química y calidad sensorial de la variedad de castaña "Martaínha" tratada con silicio RESUMEN La creciente demanda de productos saludables aumenta la presión sobre la producción de castaños debido a sus cualidades nutricionales y sus efectos beneficiosos para la salud. La variedad de castaña Martaínha está mejor adaptada y tiene gran importancia económica debido a su precocidad y a sus propiedades tecnológicas. En la agricultura, la aplicación exógena de silicio tiene un papel significativo debido a la mejora que implica en la nutrición de las plantas. Sin embargo, el conocimiento del impacto provocado por la aplicación de silicio en la producción, la calidad sensorial y la composición química de los frutos de castaño es limitado. La aplicación de Si en hojas (SL) y suelo (SS) conlleva una efecto importante en las propiedades profilácticas y los beneficios para la salud provenientes del fruto de los castaños. Además, la obtención de mayor número de frutos sanos, de buen calibre, no podridos, sin infección por tortrix y con menor pérdida de agua en las castañas poscosecha a partir de muestras de SL y SS, da cuenta de la acción positiva del Si. Por otra parte, este estudio destaca algunos efectos positivos del silicio en el perfil químico y sensorial.

PLOS ONE, 2017

The Japanese chestnut (Castanea crenata) carries resistance to Phytophthora cinnamomi, the destru... more The Japanese chestnut (Castanea crenata) carries resistance to Phytophthora cinnamomi, the destructive and widespread oomycete causing ink disease. The European chestnut (Castanea sativa), carrying little to no disease resistance, is currently threatened by the presence of the oomycete pathogen in forests, orchards and nurseries. Determining the genetic basis of P. cinnamomi resistance, for further selection of molecular markers and candidate genes, is a prominent issue for implementation of marker assisted selection in the breeding programs for resistance. In this study, the first interspecific genetic linkage map of C. sativa x C. crenata allowed the detection of QTLs for P. cinnamomi resistance. The genetic map was constructed using two independent, control-cross mapping populations. Chestnut populations were genotyped using 452 microsatellite and single nucleotide polymorphism molecular markers derived from the available chestnut transcriptomes. The consensus genetic map spans 498,9 cM and contains 217 markers mapped with an average interval of 2.3 cM. For QTL analyses, the progression rate of P. cinnamomi lesions in excised shoots inoculated was used as the phenotypic metric. Using non-parametric and composite interval mapping approaches, two QTLs were identified for ink disease resistance, distributed in two linkage groups: E and K. The presence of QTLs located in linkage group E regarding P. cinnamomi resistance is consistent with a previous preliminary study developed in American x Chinese chestnut populations, suggesting the presence of common P. cinnamomi defense mechanisms across species. Results presented here extend PLOS ONE |

Revista de Ciências Agrárias, 2016

Ink disease (caused by the pathogen Phytophthora cinnamomi) and chestnut blight (caused by the fu... more Ink disease (caused by the pathogen Phytophthora cinnamomi) and chestnut blight (caused by the fungus Cryphonectria parasitica) are the two most destructive diseases affecting European chestnut (Castanea sativa) and American chestnut (C. dentata). Therefore, breeding for resistance to both pathogens is essential for the chestnut sustainability in Europe and the United States of America. Several genomic approaches have been implemented in order to map the resistance first to ink disease and then to blight chestnut using a hybrid population: C. sativa crossed with resistant Asian species (C. crenata and C. mollissima). The transcriptome of C. sativa and C. crenata inoculated and not with P. cinnamomi was recently sequenced and allowed the identification of genes putatively involved in ink disease resistance. Taking advantage of molecular markers (microsatellite and SNPs), developed from the referred tanscriptomes and from C. mollissima transcriptome, the first C. sativa x C. crenata genetic map was constructed. Additionally, a reliable phenotyping method was established to evaluate the level of P. cinnamomi resistance of each hybrid allowing the identification of two Quantitative Trait Loci (QTLs). These results are the first step for understanding the resistance to ink disease in chestnut.

Journal of Plant Nutrition, 2014

A field trial was conducted between 2006 and 2009 in order to quantify the effect of boron (B) ap... more A field trial was conducted between 2006 and 2009 in order to quantify the effect of boron (B) application on the yield and quality of chestnuts. The trial was established in an acid soil derived from siliceous schist and two levels of B were applied. Fruit abortion and nut yield per tree were measured, and nut quality parameters and chemical composition of the kernel were determined. Foliar B concentration was 8.6 mg kg −1 in the control trees and 48.4 mg kg −1 in fertilized chestnuts. Boron improved fruit setting and promoted nut production by 77%. In 2008, the occurrence of cold temperatures enhanced the effect of B on fruit setting, which was four-fold, whereas with the normal temperatures of 2009 the increase was lower. The drought of 2009 was responsible for the ruinous chestnut caliber and shell cracking. Boron induced a significant increase in the crude fat of chestnut kernel.

Plant Pathology, 2014

Castanea sativa is susceptible to Phytophthora spp., a serious root pathogen causing ink disease,... more Castanea sativa is susceptible to Phytophthora spp., a serious root pathogen causing ink disease, while C. crenata and C. mollissima show resistance to infection. Interspecific controlled crosses were established for introgression of resistance genes from the resistant species into the susceptible C. sativa, and two mapping populations were created. Phytophthora cinnamomi resistance of each progeny was evaluated by root and excised shoot inoculation tests. The number of days of survival after root inoculation was the best discriminator of resistance to P. cinnamomi while the percentage of shoots with internal lesions was the symptom most associated with survival. The lesion progression rate in the excised shoot inoculation test was strongly and negatively correlated with survival in the root inoculation test. The excised shoot inoculation test appears to be a reliable approach for screening the resistance of chestnut genotypes to P. cinnamomi. Strong genetic correlations were obtained between survival and ink disease symptoms and among symptoms, indicating that common or linked genes might influence resistance to P. cinnamomi. The most resistant genotypes selected from this study will be tested for other commercial variables, such as ease of vegetative propagation and stock-scion compatibility.

Process Biochemistry, 2011

A rational use of native cyanobacteria for diverse biotechnology purposes requires the study of t... more A rational use of native cyanobacteria for diverse biotechnology purposes requires the study of the local abiotic factors that could potentially affect their normal growth. The present study deals with the herbicide bentazon (0.75, 1.5 and 2 mM)-induced changes in lipid profile and antioxidative defense system parameters related to oxidative stress in the rice field cyanobacterium strain Nostoc muscorum UTAD N213 grown under laboratory conditions for 72-h. Results indicate that the 72-h exposure of the strain to increasing bentazon concentrations caused: (1) a decrease of the polyunsaturated fatty acids (FAs); (2) an increase of the saturated FAs; and (3) a decrease of the unsaturation index. The activities of all of the antioxidant enzymes except for glutathione reductase showed a significant increase upon bentazon exposure in a time-and concentration-dependent manner. When compared to untreated controls, the oxidized glutathione content increased by 42, 79 and 119% with 0.75, 1.5 and 2 mM bentazon, respectively, whereas the reduced to oxidized glutathione ratio decreased by 32, 50 and 61%, respectively. The accumulation of proline in cells after herbicide exposure might prevent bentazon-induced production of reactive oxygen species and functions as a protecting agent against oxidative damage.

Applied Photosynthesis, 2012

photosynthetic performances of each species, its varieties or even its cultivars is crucial to un... more photosynthetic performances of each species, its varieties or even its cultivars is crucial to understand and advise the future. This chapter will present an overview about photosynthetic studies done in chestnut species emphasizing the abiotic stresses (drought and heat stress) and biotic stresses (ink disease) issues, contributing to understand the impact of climate change in chestnut. 2. Ecological chestnut behaviour according to its European distribution European chestnut is the only species of genus Castanea in Europe showing an outstanding evolutionary history from its likely origin in Northeast Turkey and Caucasus region in respect to other European forest tree species during last 9,000 years before present (YBP) (Mattioni et al., 2008). Palynological studies support also two main fast expansion periods, about 5,000 YBP due to glacial Pleistocene Epoch and 2,000 YBP, during the Roman Empire. Actually, in Europe, C. sativa Mill. is commonly found between the Canary Islands, the most southern point (27º N latitude) and the most northern point defined by a line passing in the south of the United Kingdom, northern Germany, Poland and Ukraine (52º N latitude). In terms of altitude, chestnut is quite widespread, since it grows at sea level in coast regions until 400 m and 2000 m a.s.l. in the inner regions of the European continent. The lowest elevations are recommended for the highest latitudes and vice versa (Bounous, 2002). The wide distribution of European chestnut, and the higher phenotypic plasticity observed in populations coming from arid regions in comparison to those that are from more wet areas, suggest the substantial adaptive variation existing among populations (Fernández-López et al., 2005). In a study comparing progenies from several European climatic contrasting locals growing under the same climatic conditions (EU funded Cascade project), populations from Greece started growth earlier followed by southern latitude progenies (south Italy and south Spain) while the plants from north Spain and North Italy initiated later. Height growth of the northern populations was higher than growth of the southern plants. The southern ones also showed an earlier growth cessation, budbreak, and a longer juvenile period than those from more north latitudes (Fernández-López et al, 2005). The importance of budbreak is due to the sensibility of the young leaves to latest frost during spring times, besides other factors such as drought tolerance. The European chestnut presents a fair effective number of alleles, decreasing diversity from northern to the most southern populations (Eriksson et al., 2005b). Nevertheless, in Iberian Peninsula there were detected more than 350 genotypes in 574 accessions (Pereira-Lorenzo et al., 2010). According to these authors, in Iberian Peninsula the two main variability origins are located in North and Centre, being the most southern ecotypes (Andalusia and Canary Islands) assigned to both of these zones, which might suggest a colonization process. This colonization by varieties from the north part of Iberian Peninsula, since there are quite different edaphoclimatic regions, suggests that this species has potential to adapt themselves to new climatic conditions and by this way to the new context of climate changes. This ability of long-term species to respond and to adapt to environmental changes though natural selection is due mainly to their high intrapopulation genetic diversity (Martin et al., 2010), demonstrating genomic SSRs significantly higher levels of diversity in terms of number of alleles, expected heterozygosity and level of polymorphism among www.intechopen.com

Plant Science, 2011

Dragon's blood is a traditional medicine widely used in the world from ancient times. However, li... more Dragon's blood is a traditional medicine widely used in the world from ancient times. However, little is known about its formation mechanism. This work aimed to gain some insights into its formation mechanism and to control its production. The results demonstrate that wounding plus causal fungal infection and keeping the wound moist are essential for efficient dragon's blood formation in Dracaena cochinchinensis. Two fungal isolates YM-266 and YM-71213 of Fusarium proliferatum increased the yield of dragon's blood in D. cochinchinensis trees by 2.7-and 3.3-times compared to that of the control (wounding alone and keeping the wound moist), respectively. The fungal induced dragon's blood had almost identical chemical constituents to that of the natural dragon's blood with a higher loureirins a and b content as analyzed by TLC and HPLC. In addition, the induced dragon's blood had similar antimicrobial activity and similar or higher antioxidant activity than that of the natural dragon's blood. The novel biological technology developed here for the production of dragon's blood is safe, repeatable, practical, and feasible for the farmers, enabling the production of dragon's blood in a sustainable way without destroying the endangered trees and environment.

Plant and Soil, 2012

Background and aims The beneficial effects of Si have mainly been observed in herbaceous plants, ... more Background and aims The beneficial effects of Si have mainly been observed in herbaceous plants, while little is known about its role in deciduous trees. The aim of this work was to evaluate the effect of foliar application of Si on chestnut leaf growth, photosynthesis and water relations in the presence of short, but intense water deficit. Methods Sili-K® solution (containing 0.12 % Si and 0.15 % K) was repeatedly (× 3) sprayed onto leaves of potted chestnut plantlets and irrigation was suspended 7 weeks later, for 8 days. Leaf growth, anatomy, as well as physiological and biochemical traits of the plantlets were studied. Results Si application enhanced chestnut growth, due to increased photosynthetic traits, including higher chlorophyll content and chlorophyll a to b ratio, photochemical efficiency of PSII, gas exchange (stomatal conductance, transpiration rate, net CO 2 assimilation) and oxygen evolution rate. Meanwhile, Si yielded larger and thinner leaves, higher xylem, specific leaf area and transpiration rate, thus being beneficial to the tree in absorbing sunlight energy for photosynthesis and in alleviating heat stress. However, Si also lowered leaf sap osmotic pressure, causing the plant to lose water more quickly, thus being more susceptible to water stress. Conclusions Si improved chestnut photosynthesis, growth, and heat stress tolerance, but it also increased the susceptibility to drought.

Photosynthetica, 2008

In crowns of chestnut trees the absorption of radiant energy is not homogeneous; leaves from the ... more In crowns of chestnut trees the absorption of radiant energy is not homogeneous; leaves from the south (S) side are the most irradiated, but leaves from the east (E) and west (W) sides receive around 70 % and those from north (N) face less than 20 % of the S irradiation. Compared to the S leaves, those from the N side were 10 % smaller, their stomata density was 14 % smaller, and their laminae were 21 % thinner. N leaves had 0.63 g(Chl) m-2 , corresponding to 93 % of total chlorophyll (Chl) amount in leaves of S side. The ratios of Chl a/b were 2.9 and 3.1 and of Chl/carotenoids (Car) 5.2 and 4.8, respectively, in N and S leaves. Net photosynthetic rate (P N) was 3.9 μmol(CO 2) m-2 s-1 in S leaves, in the E, W, and N leaves 81, 77, and 38 % of that value, respectively. Morning time (10:00 h) was the period of highest P N in the whole crown, followed by 13:00 h (85 % of S) and 16:00 h with 59 %. Below 500 µmol m-2 s-1 of photosynthetic photon flux density (PPFD), N leaves produced the highest P N , while at higher PPFD, the S leaves were most active. In addition, the fruits from S side were 10 % larger than those from the N side.

Journal of Plant Physiology, 2006

The aim of this work was to analyse the effect of temperature in three chestnut cultivars, Avelei... more The aim of this work was to analyse the effect of temperature in three chestnut cultivars, Aveleira, Judia and Longal. For this purpose, gas exchange, thylakoid membrane potential, photosynthetic pigment and lipid content data in July, September and October under different temperatures (31, 26 and 18 1C) were determined. With respect to gas exchanges, significant changes in photosynthesis rate of Aveleira were observed between July and September (7 mmol CO 2 m À2 s À1). In contrast, Judia and Longal showed a strong increase in this period, 6.1-8.5 and 4.9-6.7 mmol CO 2 m À2 s À1 , for Judia and Longal, which represent an increase of about 15% and 43%, respectively. Similar patterns were detected in daylight photosynthesis measurements for Judia and Longal, in which an almost 60% decrease was observed, in contrast to 40% for Aveleira, from morning to midday, when temperatures increased from 27 to 34 1C. In addition to high photosynthetic rates in the hottest month, Aveleira was also the sunniest cultivar according its highest value on chlorophyll a/b ratio (3.65). Cultivars also presented maximal thylakoid membrane potential at different temperatures, with their values being 20.8, 17.8 and 17.2 1C for Aveleira, Longal and Judia, respectively. These results were also supported by thylakoid fatty acid composition which indicated that the unsaturation index of Aveleira (158) was the

Journal of Hazardous Materials, 2013

A huge amount of kernel cake, which contains a variety of toxins including phorbol esters (tumor ... more A huge amount of kernel cake, which contains a variety of toxins including phorbol esters (tumor promoters), is projected to be generated yearly in the near future by the Jatropha biodiesel industry. We showed that the kernel cake strongly inhibited plant seed germination and root growth and was highly toxic to carp fingerlings, even though phorbol esters were undetectable by HPLC. Therefore it must be detoxified before disposal to the environment. A mathematic model was established to estimate the general toxicity of the kernel cake by determining the survival time of carp fingerling. A new strain (Streptomyces fimicarius YUCM 310038) capable of degrading the total toxicity by more than 97% in a 9-day solid state fermentation was screened out from 578 strains including 198 known strains and 380 strains isolated from air and soil. The kernel cake fermented by YUCM 310038 was nontoxic to plants and carp fingerlings and significantly promoted tobacco plant growth, indicating its potential to transform the toxic kernel cake to bio-safe animal feed or organic fertilizer to remove the environmental concern and to reduce the cost of the Jatropha biodiesel industry. Microbial strain profile essential for the kernel cake detoxification was discussed.

Hydrobiologia, 2010

Studies of cyanobacterial nostocacean taxa are important to the global scientific community, main... more Studies of cyanobacterial nostocacean taxa are important to the global scientific community, mainly because a significant number of beneficial strains that belong to the order Nostocales fix atmospheric nitrogen, thus contributing to the fertility of agricultural soils worldwide, while others behave as nuisance microorganisms in aquatic ecosystems due to their involvement in toxic bloom events. However, in spite of their

Environmental Toxicology, 2010

Rice fields are frequently exposed to environmental contamination by herbicides and cyanobacteria... more Rice fields are frequently exposed to environmental contamination by herbicides and cyanobacteria, as primary producers of these aquatic ecosystems, are adversely affected. Anabaena cylindrica is a cyanobacterium with a significantly widespread occurrence in Portuguese rice fields. This strain was studied throughout 72 h in laboratory conditions for its stress responses to sublethal concentrations (0.75–2 mM) of bentazon, a selective postemergence herbicide recommended for integrated weed management in rice, with special reference to oxidative stress, role of proline and intracellular antioxidant enzymes in herbicide‐induced free radicals detoxification. Activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione S‐transferase (GST) increased in a time‐ and herbicide dose‐response manner and were higher than those in the control samples after 72 h. A time‐ and concentration‐dependent increase of malondialdehyde (M...

CyTA - Journal of Food, 2011

Study of morphological and chemical diversity in chestnut trees (var. "Judia") as a function of t... more Study of morphological and chemical diversity in chestnut trees (var. "Judia") as a function of temperature sum Estudio de la diversidad morfológica y química del fruto de castaña (var.

O ColUTAD é um castanheiro híbrido, resultante do cruzamento entre o castanheiro europeu (Castane... more O ColUTAD é um castanheiro híbrido, resultante do cruzamento entre o castanheiro europeu (Castanea sativa) e o castanheiro japonês (Castanea crenata). Este clone, disponível no mercado, tem como principais características o facto de ser considerado bastante resistente à doença da tinta e de poder funcionar como porta-enxerto das variedades tradicionais com vista à resolução de uma das principais doenças do nosso castanheiro potenciada pelas alterações climáticas. Este hibrido apresenta um porte mais ananicante do que o castanheiro europeu permitindo apertar os compassos de plantação e aumentar a produção de castanha nos primeiros anos do souto. Contudo, a produção da castanha é fortemente condicionada pelas condições meteorológicas médias e extremas verificadas durante o seu ciclo anual. Assim, é importante testar a adaptação de novos porta-enxertos e variedades tradicionais de castanha em situações extremas para a espécie face à variabilidade do clima e alterações climáticas futura...

<p>The chestnut trees are well adaptated to... more <p>The chestnut trees are well adaptated to temperate and humid climates, with moderate annual thermal contrast and without long and severe summer droughts. Bioclimatic studies suggest that chestnut trees have special needs, including at least six months with average monthly air temperature above 10 ⁰C, total annual precipitation of 800 – 900 mm, and 25% of annual precipitation in summer. Weather is also determinant in the phenology of the species. For example, the suitable average air temperature range is: 13 – 15⁰C to initiate the phenological activity, 18 – 20⁰C for flowering, and 20 – 22⁰C for maturation. Therefore chestnut production is highly affected by adverse weather conditions and can be severely reduced by the occurrence of extreme weather/climate extremes: late frosts, heat waves, heavy rainfall, wind gusts, maximum air temperature lower than 25⁰C during flowering or above 32⁰C, which cause thermoinhibition of vegetative activity. Thus, it is important to characterize the chestnut producing regions in present and future climate and estimate how, when and where the weather conditions will be maintained or changed. For this study we used meteorological data from ERA5 for the 1981 – 2010 period and several GCM-RCM simulations from CORDEX Bias-adjusted RCM data for 2011 – 2100 period to assess the climate for current and two future scenarios (RCP 4.5 and RCP 8.5). The meteorological variables selected for this study have been identified in previous studies as having the greatest influence in the phenological activity of the chestnut tree and on the chestnut productivity. The results include the identification of the regions where: (i) the variables will have significantly different statistical distributions in the future; (ii) will be necessary to adopt hazard risk management and climate adaptation measures, including substitution by other varieties more adapted to future conditions or the development of genetic improvement programs; and, (iii) the identification of new production areas.</p>

Revista de Ciências Agrárias, 2018

Different types of irrigation systems can be used in chestnut orchards. To understand which one g... more Different types of irrigation systems can be used in chestnut orchards. To understand which one grants higher yield values treatments were applied in adult trees: drip system-TI; micro-sprinkler system-SI; non-irrigated system-NI. The study covers two years in the northeast of Portugal. Irrigation was triggered every time stem water potential was lower than-1.2 MPa. The study considers costs with the equipment, water and labour, and the income from the chestnuts' sale. Due to the hotter conditions of 2016 more water was supplied (93 mm) than in 2015 (47 mm). Little more water was furnished in SI (73 mm) than in TI (67 mm). Production was 27% higher in irrigated (48 kg/tree) than in NI trees (38 kg/tree) and in relation to the canopy's area (kg/m 2) the TI produced 18% and SI 29% more than NI. Annual costs were higher with irrigation (4654, 4549 and 1530 €/ha for SI, TI and NI, respectively) but the higher income (22126, 21984 and 16174 €/ha for TI, SI and NI respectively) made up for the investment. The profits from irrigated trees can be 22% or 37% higher than in non irrigated ones, for 1 ha or 5 ha, respectively.

International Journal of Environment, Agriculture and Biotechnology, 2017

The European chestnut (Castanea sativa Mill.) is a specie with great economic importance in Europ... more The European chestnut (Castanea sativa Mill.) is a specie with great economic importance in Europe that have been present for thousands of years. In Portugal, the chestnut helps to maintain a positive trade balance, by contributing to the gross national product (GDP). One of the biggest threats for the chestnut is the ink disease caused by Phytophthora cinnamomi, this disease is problematic to chestnut crop with a damaging impact. Silicon (Si) is classified as a beneficial nutrient, having the ability to make plants more resistant to attacks by pathogens. Studies on the effect of silicon on chestnut are practically non-existent, so the aim of this study was to evaluate the impact of silicon in the resistance of chestnut plants to P. cinnamomi. The plants were treated by 0 mM, 5 mM, 7.5mM and 10 mM SiK ® with the analyzed mad at 0, 15 and 30 days after inoculation by P. cinnamomi. These findings showed that the Si-treated plants had higher survival rate resulted from the presence of phytoliths in root tissues, that acted as a mechanical barrier reducing the development of pathogenic structures and they arealso associated with the improvement on antioxidant activity through the increase of CAT and SOD, higher values of total phenols compounds and less oxidative damage. The presence of Si in PDA medium reduced the growth of P. cinnamomi all over the time, presenting high PI. This work shows that the Si fertilization in chestnut plants contributes to increase the resistance against P. cinnamomi infection.

CyTA - Journal of Food, 2019

The increasing demand for healthy products rises the pressure on the chestnut production due to t... more The increasing demand for healthy products rises the pressure on the chestnut production due to their nutritional qualities and beneficial health effects. Martaínha chestnut variety is most welladapted with great economic importance due to its precocity and technological properties. The exogenous application of Silicon has an important role in agriculture because of improvement of plants nutrition. Nevertheless, the knowledge of impact of Silicon application in the production, sensory quality and chemical composition of chestnut fruits is limited. The application of Si in leaves (SL) and soil (SS) have important action on the prophylactic properties and the promotion of chestnuts health. Moreover, higher number of healthy fruits, caliber, fruits without rotten and tortrix infection and lower water loss in post-harvest chestnuts, in SL and SS samples, highlights the Si positive action. Additionally this study emphasizes some positive effects of Silicon on the chemical and sensory profile. Producción, composición química y calidad sensorial de la variedad de castaña "Martaínha" tratada con silicio RESUMEN La creciente demanda de productos saludables aumenta la presión sobre la producción de castaños debido a sus cualidades nutricionales y sus efectos beneficiosos para la salud. La variedad de castaña Martaínha está mejor adaptada y tiene gran importancia económica debido a su precocidad y a sus propiedades tecnológicas. En la agricultura, la aplicación exógena de silicio tiene un papel significativo debido a la mejora que implica en la nutrición de las plantas. Sin embargo, el conocimiento del impacto provocado por la aplicación de silicio en la producción, la calidad sensorial y la composición química de los frutos de castaño es limitado. La aplicación de Si en hojas (SL) y suelo (SS) conlleva una efecto importante en las propiedades profilácticas y los beneficios para la salud provenientes del fruto de los castaños. Además, la obtención de mayor número de frutos sanos, de buen calibre, no podridos, sin infección por tortrix y con menor pérdida de agua en las castañas poscosecha a partir de muestras de SL y SS, da cuenta de la acción positiva del Si. Por otra parte, este estudio destaca algunos efectos positivos del silicio en el perfil químico y sensorial.

PLOS ONE, 2017

The Japanese chestnut (Castanea crenata) carries resistance to Phytophthora cinnamomi, the destru... more The Japanese chestnut (Castanea crenata) carries resistance to Phytophthora cinnamomi, the destructive and widespread oomycete causing ink disease. The European chestnut (Castanea sativa), carrying little to no disease resistance, is currently threatened by the presence of the oomycete pathogen in forests, orchards and nurseries. Determining the genetic basis of P. cinnamomi resistance, for further selection of molecular markers and candidate genes, is a prominent issue for implementation of marker assisted selection in the breeding programs for resistance. In this study, the first interspecific genetic linkage map of C. sativa x C. crenata allowed the detection of QTLs for P. cinnamomi resistance. The genetic map was constructed using two independent, control-cross mapping populations. Chestnut populations were genotyped using 452 microsatellite and single nucleotide polymorphism molecular markers derived from the available chestnut transcriptomes. The consensus genetic map spans 498,9 cM and contains 217 markers mapped with an average interval of 2.3 cM. For QTL analyses, the progression rate of P. cinnamomi lesions in excised shoots inoculated was used as the phenotypic metric. Using non-parametric and composite interval mapping approaches, two QTLs were identified for ink disease resistance, distributed in two linkage groups: E and K. The presence of QTLs located in linkage group E regarding P. cinnamomi resistance is consistent with a previous preliminary study developed in American x Chinese chestnut populations, suggesting the presence of common P. cinnamomi defense mechanisms across species. Results presented here extend PLOS ONE |

Revista de Ciências Agrárias, 2016

Ink disease (caused by the pathogen Phytophthora cinnamomi) and chestnut blight (caused by the fu... more Ink disease (caused by the pathogen Phytophthora cinnamomi) and chestnut blight (caused by the fungus Cryphonectria parasitica) are the two most destructive diseases affecting European chestnut (Castanea sativa) and American chestnut (C. dentata). Therefore, breeding for resistance to both pathogens is essential for the chestnut sustainability in Europe and the United States of America. Several genomic approaches have been implemented in order to map the resistance first to ink disease and then to blight chestnut using a hybrid population: C. sativa crossed with resistant Asian species (C. crenata and C. mollissima). The transcriptome of C. sativa and C. crenata inoculated and not with P. cinnamomi was recently sequenced and allowed the identification of genes putatively involved in ink disease resistance. Taking advantage of molecular markers (microsatellite and SNPs), developed from the referred tanscriptomes and from C. mollissima transcriptome, the first C. sativa x C. crenata genetic map was constructed. Additionally, a reliable phenotyping method was established to evaluate the level of P. cinnamomi resistance of each hybrid allowing the identification of two Quantitative Trait Loci (QTLs). These results are the first step for understanding the resistance to ink disease in chestnut.

Journal of Plant Nutrition, 2014

A field trial was conducted between 2006 and 2009 in order to quantify the effect of boron (B) ap... more A field trial was conducted between 2006 and 2009 in order to quantify the effect of boron (B) application on the yield and quality of chestnuts. The trial was established in an acid soil derived from siliceous schist and two levels of B were applied. Fruit abortion and nut yield per tree were measured, and nut quality parameters and chemical composition of the kernel were determined. Foliar B concentration was 8.6 mg kg −1 in the control trees and 48.4 mg kg −1 in fertilized chestnuts. Boron improved fruit setting and promoted nut production by 77%. In 2008, the occurrence of cold temperatures enhanced the effect of B on fruit setting, which was four-fold, whereas with the normal temperatures of 2009 the increase was lower. The drought of 2009 was responsible for the ruinous chestnut caliber and shell cracking. Boron induced a significant increase in the crude fat of chestnut kernel.

Plant Pathology, 2014

Castanea sativa is susceptible to Phytophthora spp., a serious root pathogen causing ink disease,... more Castanea sativa is susceptible to Phytophthora spp., a serious root pathogen causing ink disease, while C. crenata and C. mollissima show resistance to infection. Interspecific controlled crosses were established for introgression of resistance genes from the resistant species into the susceptible C. sativa, and two mapping populations were created. Phytophthora cinnamomi resistance of each progeny was evaluated by root and excised shoot inoculation tests. The number of days of survival after root inoculation was the best discriminator of resistance to P. cinnamomi while the percentage of shoots with internal lesions was the symptom most associated with survival. The lesion progression rate in the excised shoot inoculation test was strongly and negatively correlated with survival in the root inoculation test. The excised shoot inoculation test appears to be a reliable approach for screening the resistance of chestnut genotypes to P. cinnamomi. Strong genetic correlations were obtained between survival and ink disease symptoms and among symptoms, indicating that common or linked genes might influence resistance to P. cinnamomi. The most resistant genotypes selected from this study will be tested for other commercial variables, such as ease of vegetative propagation and stock-scion compatibility.

Process Biochemistry, 2011

A rational use of native cyanobacteria for diverse biotechnology purposes requires the study of t... more A rational use of native cyanobacteria for diverse biotechnology purposes requires the study of the local abiotic factors that could potentially affect their normal growth. The present study deals with the herbicide bentazon (0.75, 1.5 and 2 mM)-induced changes in lipid profile and antioxidative defense system parameters related to oxidative stress in the rice field cyanobacterium strain Nostoc muscorum UTAD N213 grown under laboratory conditions for 72-h. Results indicate that the 72-h exposure of the strain to increasing bentazon concentrations caused: (1) a decrease of the polyunsaturated fatty acids (FAs); (2) an increase of the saturated FAs; and (3) a decrease of the unsaturation index. The activities of all of the antioxidant enzymes except for glutathione reductase showed a significant increase upon bentazon exposure in a time-and concentration-dependent manner. When compared to untreated controls, the oxidized glutathione content increased by 42, 79 and 119% with 0.75, 1.5 and 2 mM bentazon, respectively, whereas the reduced to oxidized glutathione ratio decreased by 32, 50 and 61%, respectively. The accumulation of proline in cells after herbicide exposure might prevent bentazon-induced production of reactive oxygen species and functions as a protecting agent against oxidative damage.

Applied Photosynthesis, 2012

photosynthetic performances of each species, its varieties or even its cultivars is crucial to un... more photosynthetic performances of each species, its varieties or even its cultivars is crucial to understand and advise the future. This chapter will present an overview about photosynthetic studies done in chestnut species emphasizing the abiotic stresses (drought and heat stress) and biotic stresses (ink disease) issues, contributing to understand the impact of climate change in chestnut. 2. Ecological chestnut behaviour according to its European distribution European chestnut is the only species of genus Castanea in Europe showing an outstanding evolutionary history from its likely origin in Northeast Turkey and Caucasus region in respect to other European forest tree species during last 9,000 years before present (YBP) (Mattioni et al., 2008). Palynological studies support also two main fast expansion periods, about 5,000 YBP due to glacial Pleistocene Epoch and 2,000 YBP, during the Roman Empire. Actually, in Europe, C. sativa Mill. is commonly found between the Canary Islands, the most southern point (27º N latitude) and the most northern point defined by a line passing in the south of the United Kingdom, northern Germany, Poland and Ukraine (52º N latitude). In terms of altitude, chestnut is quite widespread, since it grows at sea level in coast regions until 400 m and 2000 m a.s.l. in the inner regions of the European continent. The lowest elevations are recommended for the highest latitudes and vice versa (Bounous, 2002). The wide distribution of European chestnut, and the higher phenotypic plasticity observed in populations coming from arid regions in comparison to those that are from more wet areas, suggest the substantial adaptive variation existing among populations (Fernández-López et al., 2005). In a study comparing progenies from several European climatic contrasting locals growing under the same climatic conditions (EU funded Cascade project), populations from Greece started growth earlier followed by southern latitude progenies (south Italy and south Spain) while the plants from north Spain and North Italy initiated later. Height growth of the northern populations was higher than growth of the southern plants. The southern ones also showed an earlier growth cessation, budbreak, and a longer juvenile period than those from more north latitudes (Fernández-López et al, 2005). The importance of budbreak is due to the sensibility of the young leaves to latest frost during spring times, besides other factors such as drought tolerance. The European chestnut presents a fair effective number of alleles, decreasing diversity from northern to the most southern populations (Eriksson et al., 2005b). Nevertheless, in Iberian Peninsula there were detected more than 350 genotypes in 574 accessions (Pereira-Lorenzo et al., 2010). According to these authors, in Iberian Peninsula the two main variability origins are located in North and Centre, being the most southern ecotypes (Andalusia and Canary Islands) assigned to both of these zones, which might suggest a colonization process. This colonization by varieties from the north part of Iberian Peninsula, since there are quite different edaphoclimatic regions, suggests that this species has potential to adapt themselves to new climatic conditions and by this way to the new context of climate changes. This ability of long-term species to respond and to adapt to environmental changes though natural selection is due mainly to their high intrapopulation genetic diversity (Martin et al., 2010), demonstrating genomic SSRs significantly higher levels of diversity in terms of number of alleles, expected heterozygosity and level of polymorphism among www.intechopen.com

Plant Science, 2011

Dragon's blood is a traditional medicine widely used in the world from ancient times. However, li... more Dragon's blood is a traditional medicine widely used in the world from ancient times. However, little is known about its formation mechanism. This work aimed to gain some insights into its formation mechanism and to control its production. The results demonstrate that wounding plus causal fungal infection and keeping the wound moist are essential for efficient dragon's blood formation in Dracaena cochinchinensis. Two fungal isolates YM-266 and YM-71213 of Fusarium proliferatum increased the yield of dragon's blood in D. cochinchinensis trees by 2.7-and 3.3-times compared to that of the control (wounding alone and keeping the wound moist), respectively. The fungal induced dragon's blood had almost identical chemical constituents to that of the natural dragon's blood with a higher loureirins a and b content as analyzed by TLC and HPLC. In addition, the induced dragon's blood had similar antimicrobial activity and similar or higher antioxidant activity than that of the natural dragon's blood. The novel biological technology developed here for the production of dragon's blood is safe, repeatable, practical, and feasible for the farmers, enabling the production of dragon's blood in a sustainable way without destroying the endangered trees and environment.

Plant and Soil, 2012

Background and aims The beneficial effects of Si have mainly been observed in herbaceous plants, ... more Background and aims The beneficial effects of Si have mainly been observed in herbaceous plants, while little is known about its role in deciduous trees. The aim of this work was to evaluate the effect of foliar application of Si on chestnut leaf growth, photosynthesis and water relations in the presence of short, but intense water deficit. Methods Sili-K® solution (containing 0.12 % Si and 0.15 % K) was repeatedly (× 3) sprayed onto leaves of potted chestnut plantlets and irrigation was suspended 7 weeks later, for 8 days. Leaf growth, anatomy, as well as physiological and biochemical traits of the plantlets were studied. Results Si application enhanced chestnut growth, due to increased photosynthetic traits, including higher chlorophyll content and chlorophyll a to b ratio, photochemical efficiency of PSII, gas exchange (stomatal conductance, transpiration rate, net CO 2 assimilation) and oxygen evolution rate. Meanwhile, Si yielded larger and thinner leaves, higher xylem, specific leaf area and transpiration rate, thus being beneficial to the tree in absorbing sunlight energy for photosynthesis and in alleviating heat stress. However, Si also lowered leaf sap osmotic pressure, causing the plant to lose water more quickly, thus being more susceptible to water stress. Conclusions Si improved chestnut photosynthesis, growth, and heat stress tolerance, but it also increased the susceptibility to drought.

Photosynthetica, 2008

In crowns of chestnut trees the absorption of radiant energy is not homogeneous; leaves from the ... more In crowns of chestnut trees the absorption of radiant energy is not homogeneous; leaves from the south (S) side are the most irradiated, but leaves from the east (E) and west (W) sides receive around 70 % and those from north (N) face less than 20 % of the S irradiation. Compared to the S leaves, those from the N side were 10 % smaller, their stomata density was 14 % smaller, and their laminae were 21 % thinner. N leaves had 0.63 g(Chl) m-2 , corresponding to 93 % of total chlorophyll (Chl) amount in leaves of S side. The ratios of Chl a/b were 2.9 and 3.1 and of Chl/carotenoids (Car) 5.2 and 4.8, respectively, in N and S leaves. Net photosynthetic rate (P N) was 3.9 μmol(CO 2) m-2 s-1 in S leaves, in the E, W, and N leaves 81, 77, and 38 % of that value, respectively. Morning time (10:00 h) was the period of highest P N in the whole crown, followed by 13:00 h (85 % of S) and 16:00 h with 59 %. Below 500 µmol m-2 s-1 of photosynthetic photon flux density (PPFD), N leaves produced the highest P N , while at higher PPFD, the S leaves were most active. In addition, the fruits from S side were 10 % larger than those from the N side.

Journal of Plant Physiology, 2006

The aim of this work was to analyse the effect of temperature in three chestnut cultivars, Avelei... more The aim of this work was to analyse the effect of temperature in three chestnut cultivars, Aveleira, Judia and Longal. For this purpose, gas exchange, thylakoid membrane potential, photosynthetic pigment and lipid content data in July, September and October under different temperatures (31, 26 and 18 1C) were determined. With respect to gas exchanges, significant changes in photosynthesis rate of Aveleira were observed between July and September (7 mmol CO 2 m À2 s À1). In contrast, Judia and Longal showed a strong increase in this period, 6.1-8.5 and 4.9-6.7 mmol CO 2 m À2 s À1 , for Judia and Longal, which represent an increase of about 15% and 43%, respectively. Similar patterns were detected in daylight photosynthesis measurements for Judia and Longal, in which an almost 60% decrease was observed, in contrast to 40% for Aveleira, from morning to midday, when temperatures increased from 27 to 34 1C. In addition to high photosynthetic rates in the hottest month, Aveleira was also the sunniest cultivar according its highest value on chlorophyll a/b ratio (3.65). Cultivars also presented maximal thylakoid membrane potential at different temperatures, with their values being 20.8, 17.8 and 17.2 1C for Aveleira, Longal and Judia, respectively. These results were also supported by thylakoid fatty acid composition which indicated that the unsaturation index of Aveleira (158) was the

Journal of Hazardous Materials, 2013

A huge amount of kernel cake, which contains a variety of toxins including phorbol esters (tumor ... more A huge amount of kernel cake, which contains a variety of toxins including phorbol esters (tumor promoters), is projected to be generated yearly in the near future by the Jatropha biodiesel industry. We showed that the kernel cake strongly inhibited plant seed germination and root growth and was highly toxic to carp fingerlings, even though phorbol esters were undetectable by HPLC. Therefore it must be detoxified before disposal to the environment. A mathematic model was established to estimate the general toxicity of the kernel cake by determining the survival time of carp fingerling. A new strain (Streptomyces fimicarius YUCM 310038) capable of degrading the total toxicity by more than 97% in a 9-day solid state fermentation was screened out from 578 strains including 198 known strains and 380 strains isolated from air and soil. The kernel cake fermented by YUCM 310038 was nontoxic to plants and carp fingerlings and significantly promoted tobacco plant growth, indicating its potential to transform the toxic kernel cake to bio-safe animal feed or organic fertilizer to remove the environmental concern and to reduce the cost of the Jatropha biodiesel industry. Microbial strain profile essential for the kernel cake detoxification was discussed.

Hydrobiologia, 2010

Studies of cyanobacterial nostocacean taxa are important to the global scientific community, main... more Studies of cyanobacterial nostocacean taxa are important to the global scientific community, mainly because a significant number of beneficial strains that belong to the order Nostocales fix atmospheric nitrogen, thus contributing to the fertility of agricultural soils worldwide, while others behave as nuisance microorganisms in aquatic ecosystems due to their involvement in toxic bloom events. However, in spite of their

Environmental Toxicology, 2010

Rice fields are frequently exposed to environmental contamination by herbicides and cyanobacteria... more Rice fields are frequently exposed to environmental contamination by herbicides and cyanobacteria, as primary producers of these aquatic ecosystems, are adversely affected. Anabaena cylindrica is a cyanobacterium with a significantly widespread occurrence in Portuguese rice fields. This strain was studied throughout 72 h in laboratory conditions for its stress responses to sublethal concentrations (0.75–2 mM) of bentazon, a selective postemergence herbicide recommended for integrated weed management in rice, with special reference to oxidative stress, role of proline and intracellular antioxidant enzymes in herbicide‐induced free radicals detoxification. Activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione S‐transferase (GST) increased in a time‐ and herbicide dose‐response manner and were higher than those in the control samples after 72 h. A time‐ and concentration‐dependent increase of malondialdehyde (M...

CyTA - Journal of Food, 2011

Study of morphological and chemical diversity in chestnut trees (var. "Judia") as a function of t... more Study of morphological and chemical diversity in chestnut trees (var. "Judia") as a function of temperature sum Estudio de la diversidad morfológica y química del fruto de castaña (var.