Impact of Anthracnose on Avocado Production in Kenya (original) (raw)
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Anthracnose Disease of Mango: Epidemiology, Impact and Management Options
Current and Emerging Challenges in the Diseases of Trees [Working Title]
Mango is one of the frequently cultivated seasonal fruit crops in several tropical and subtropical regions. It is consumed as whole fruits apart from serving as raw materials for most industries that are into mineral production. Mango production is, however, constrained by diseases, pests, and poor post-harvest handling of fruits. Anthracnose disease, caused by Colletotrichum gloeosporioides Penz and Sacc, is one of the most important yields limiting constraint in mango production across the globe. The disease occurs in both the field and post-harvesting. In the field, it affects aboveground parts, such as the stem, branches, leaves, flowers, and fruits. Anthracnose disease reduces the shelve life and marketability of mango fruit. In Ghana, anthracnose disease is responsible for about 30% yield/fruit loss. Most farmers do not control it, although some have resorted to the application of various fungicides not registered for mango anthracnose disease management in Ghana. This chapter...
Book of Abstracts, 2021
The avocado industry of Kenya is more focused on export market destinations, implying that higher volumes of this fruit target the global markets for sustainable income generation. Besides other factors, one major threat to avocado postharvest management for maintenance of high-quality fruits in Kenya is anthracnose (caused by Colletotrichum gloeosporioides). As the export market of avocado fruits reaches saturation, it will be necessary to source alternative markets to absorb the surplus. To access such markets, longer shelf life and transportation durations are critical. In addition, effective treatment of avocado against anthracnose disease at the post-harvest level remains critical towards sustaining their quality attributes. Physiologically mature avocado fruits are highly susceptible to deterioration by anthracnose infection among other factors which include, soft landing, uneven ripening, decay and mechanical damage. Suitable post-harvest treatment of avocado is hence, necessary. Development of avocado postharvest management practices using eco-friendly and non-chemical techniques to prevent anthracnose is a suitable alternative to maintaining their post-harvest quality. The huge postharvest losses incurred in avocado fruits due to infection by anthracnose can be reduced significantly using physical (hot water treatments, electrolyzed oxidizing water treatment, light emitting diode and ultraviolet radiations and postharvest temperature management) and biological approaches (essential plant extracts, biodegradable polymers and plant defense elicitors). Consequently, this review provides a summary of physical and biological techniques for sustainable postharvest management of anthracnose based on the published research findings
Plant Pathology & Quarantine, 2016
Field surveys were conducted in North West Ethiopia, Pawi district during 2011 and 2012 cropping seasons to determine the distribution of anthracnose and the association of disease parameters (incidence and severity) with climatic variables and crop management practices. Nineteen mango fields were surveyed and all were infected by anthracnose. The surveyed fields were at two growth stages, with flowering (2011) and fruiting (2012). There was no statistically significant difference for the incidence of anthracnose between the two seasons with mean disease incidence of 65.7% in 2011 and 66.5% in 2012. However, severity of anthracnose was statistically significantly different (p <0.05) in 2012 cropping season (81.2%) than in the 2011 cropping season (59.8%). Regression analysis for the relation between agronomical variables, as independent variables, and mango anthracnose severity, as dependent variable, showed contributions of environmental and agronomical variables such as planting stage, field size, plant density, altitude and villages for statistically significant anthracnose severity during fruiting stages than flowering stages. As altitude increases, disease severity decreases in the survey villages in Pawi district, Ethiopia.
Prevalence of Colletotrichum spp. Infecting Fruits in Southern Ethiopia
2015
3 Abstract: Colletotrichum is an important fungal genus infecting several crops including avocado, papaya and banana. The current study was conducted to i) assess the incidence and severity of anthracnose of in avocado and papaya fields of southern Ethiopia; ii) identify the Colletotrichum species infecting both crops. For this purpose, field surveys were carried out in Wolaita, Wondo Genet and Ziway fruits with and without visible symptoms of anthracnose were collected; isolates were identified to a species level and characterized based on their phenotypic features. Results of the field surveys revealed the prevalence of anthracnose in all the locations. However, both disease incidence and severity varied markedly across the locations. Both incidence and severity of avocado and papaya anthracnose were found to be highest in Wondo Genet (45 and 22% for avocado and 39.7 and 22% for papaya, respectively) followed by Wolaita (32.4 and 16.8% for avocado and 36 and 16.6% for papaya, resp...
Susceptibility of Mango Varieties to Anthracnose Fruit Rot in South West Nigeria
American Journal of Agricultural and Biological Sciences
Anthracnose fruit rot is the most devastating postharvest disease of mango fruits in Nigeria. This study, investigated the susceptibility of mango varieties commonly grown in South West Nigeria to fruit anthracnose. Four locations (Ayetoro, Ibadan, Ogbomosho and Agege) in South west Nigeria, which fall along mango production belt, were selected for this study. Physiologically matured mango fruits freshly harvested separately from Alphonso, Julie and Ogbomosho varieties were ripened at room temperature for 16 days under alternating 12 h light and dark periods to assess the incidence and severity of fruit anthracnose in each variety. In addition, freshly harvested healthy fruits were deliberately inoculated with spores of Colletotrichum gloeosporioides to evaluate the degree of susceptibility of the tested varieties. Results showed that Ogbomosho variety had the lowest percentage of 66.7% disease incidence and 44% disease severity. Similarly, lesion diameter was highest in Alphonso variety (1.18 cm) with the least (0.91 cm) in Ogbomosho variety. The study found Ogbomosho variety less susceptible to anthracnose and consequently recommended it to farmers.
Mycobiology, 2018
The filamentous Ascomycota Colletotrichum gloeosporioides sensu lato is a fungus that has been reported worldwide as a causal agent of anthracnose disease in avocado and other crops. In Mexico, this species affects fruits from an early stage of development in the orchard until the post-harvest stage. Although fungicides are continuously applied to control Colletotrichum species, pericarp cankers and soft rot mesocarp in fruits are still frequently observed. Considering the lack of a precise description of the causative agent, the aim of the current study was to determine the pathogens involved in this symptomatology. Twenty-four isolates were consistently obtained from the pericarp of avocado fruits cv. "Hass" collected in the central avocado-producing area of Mexico. Morphological features such as colony growth, conidia size, and mycelial appressorium were assessed. Bayesian multilocus phylogenetic analyses were performed using amplified sequences of the internal transcribed spacer region of the nuclear ribosomal DNA; actin, chitin synthase, glyceraldehyde-3-phosphate dehydrogenase partial genes; and APn2-Mat1-2 intergenic spacer and mating type Mat1-2 partial gene from the nine selected isolates. In addition, fruits were inoculated with a conidial suspension and reproducible symptoms confirmed the presence of Colletotrichum fructicola in this area. This pathogenic species can now be added to those previously reported in the country, such as C. acutatum, C. boninense, C. godetiae, C. gloeosporioides, and C. karstii. Disease management programs to reduce the incidence of anthracnose should include C. fructicola to determine its response to fungicides that are routinely applied, considering that the appearance of new species is affecting the commercial quality of the fruits and shifting the original population structure.
2019
Mango is one of the most economically important fruit crop in the north of Côte d'Ivoire. However, its production and productivity are limited by various biotic and abiotic factors. Amongst fungal disease, mango anthracnose is recorded to be the most important disease in the northern districts. This study assessed the incidence and severity of pre-and post-harvest anthracnose to compare the level of orchard infestation in the seven mango producing districts in the north of Côte d'Ivoire. Anthracnose disease incidence and severity varied from locality to locality both in dry and rainy season. Disease intensity was higher in rainy season than dry season. In dry and rainy seasons, the highest disease incidence (19.08% and 32.25%) was recorded in Bèrèdougou and the least in Zèguèrè. Pre and post-harvest anthracnose correlated significantly indicating that infection initiated in field and remained latent until fruits repining. The disease was also more severe on fruits than leaves. On fruits disease incidence and severity were higher in Dianra village (90% and 100%) and Bèrèdougou (36% and 40%). The lowest disease incidence (7.5%) and severity (1.5%) on fruits were observed in Zèguèrè. This study showed that anthracnose disease is one the most important threat to production and marketing of fresh mango fruits in the north of Côte d'Ivoire.
International Journal of Scientific & Technology Research, 2012
Mango (Mangifera indica L.) fruit rot caused by anthracnose is the most economically important postharvest disease limiting shelf life and export of fresh mango fruits in Nigeria. This study; investigated the etiology, disease incidence and disease severity of man go fruit anthracnose in Southwestern Nigeria. The result of the investigation revealed that 96 isolates out of 231 fungi isolates recovered from symptomatic mango fruits were Colletotrichum gloeosporioides isolates based on their whitish orange colony, septated hyphae and capsule-like appearance and pathogenicity test conducted. Other 14 fungi species encountered, accounted for 135 isolates. Colletotrichum gloeosporioides was more frequently encountered in all the study areas. One-way ANOVA with Duncan Multiple Range Test conducted, revealed that Ogbomosho area had the highest disease incidence mean of 48% and severity mean of 37.87% while Ayetoro recorded the least disease incidence with mean incidence of 37.33% and sever...
Detection and epidemiological progress of quiescent avocado diseases
Ciência Rural, 2019
ABSTRACT: One of the major problems in the commercialization of avocados is the incidence of postharvest diseases, especially anthracnose (Colletotrichum spp.) and stem-end rot (Lasiodiplodia theobromae, Fusicoccum aesculi and Neofusicoccum spp.). As there is a lack of epidemiological information on these pathosystems, the objective of this study was to establish a method to detect quiescent infections and characterize their temporal progression and spatial pattern in a commercial orchard. Detection of quiescent infections was evaluated in flowers and fruits that were immature and in commercial harvest stage, treated with paraquat, ethrel or water. Treatment of flowers and immature fruits with paraquat led to rapid detection of Colletotrichum spp. In two seasons of a ‘Hass’ avocado orchard, the incidence of diseases was evaluated from open flowers to fruit harvest, totaling 11 evaluations at biweekly intervals. When fruits reached the harvest stage, the spatial distribution of disea...