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Papers by Plant Protection

Plant Protection , 2019

Malakand Division in northwest Pakistan is known for delicious sweet orange, locally called Malta... more Malakand Division in northwest Pakistan is known for delicious sweet orange, locally called Malta (Citrus sinensis). However, both quality and quantity of the citrus produce has seen a decline over the past few decades. Among production constraints, Huanglongbing (HLB) caused by phloem-limited alpha proteobacterium Candidatus Liberibacter asiaticus (CLas) -an endosymbiont of Asian Citrus Psyllid (Diaphorina citri), is of great economic significance. Therefore, we assessed HLB incidence through symptom-based surveys in major citrus growing areas of Khyber Pakhtunkhwa (KP), Northwest Pakistan. The presence or absence of CLas in the collected citrus samples was confirmed by PCR (Polymerase Chain Reaction) using three set of primers (LSS/LAS606, OI1/OI2C “16S rDNA” and MH353/MH354 “operon “nusG-rplK”). An average disease incidence of 92% and severity of 34% were recorded from main production zones in district Swat, KP. Likewise, in district Lower Dir, HLB had disease incidence and severity of 64% and 24%, respectively. Molecular diagnostics using 16S rDNA-specific primer LSS/LAS606 and OI1/OI2C, yielded characteristic bands of 500 bp and 1160 bp, from all five pooled samples from Swat district, while only two samples of Dir tested positive for both primers. Using an alternative primer MH353/MH354 (nusG-rplK) showed positive amplification for four samples from Swat and two samples of Dir with an amplicon of 631 bp. To assess the molecular diversity of the CLas, Sanger sequencing was carried out based on16S rDNA gene. Sequence analysis of 16S rDNA gene from all samples revealed maximum similarity with C. Liberibacter asiaticus. Among studied isolates, SwKjuPk-5 (MH374503) and SwMtaPk-2 (MH374500) isolates appeared to be more divergent and grouped in separate clad as compared to remaining isolates of Swat and Dir.

Plant Protection , 2019

Quinoa (Chenopodium quinoa L.) is a recently introduced pseudocereal crop in Pakistan. In the pre... more Quinoa (Chenopodium quinoa L.) is a recently introduced pseudocereal crop in Pakistan. In the present study, methanolic extract was partitioned with n-hexane, chloroform and finally with ethyl acetate. The ethyl acetate fraction was subjected to GC-MS analysis for the identification of various antimicrobial and antioxidant constituents. Thirteen compounds were identified through GC-MS analysis of this fraction. Among these, 11 compounds possessed antibacterial, antifungal and/or antioxidant properties as reported in literature. These include naphthalene; tetradecane; hexadecane; pentadecane; cyclohexadecane; 1,2-benzenedicarboxylic acid, bis(2-methylpropyl) ester; dibutyl phthalate; 1-nonadecene; 1-octadecanol; 9-hexacosene; and 1,2-benzenedicarboxylic acid, mono(2-ethylhexyl) ester.

Plant Protection , 2019

Many rhabditid nematodes like Metarhabditis belonging to the bacteriophage group are considered t... more Many rhabditid nematodes like Metarhabditis belonging to the bacteriophage group are considered to be necromenic associates of insects and used to be facultative entomopathogenic nematodes or as biocontrol agents. These nematodes can be safely used against insect pests of different crops and vegetables. In the present study, nematode specimens of new and known species were collected from different areas of Sindh and isolated from soil samples by baiting technique using last instar Galleria mellonella. One new nematode species Metarhabditis longicaudata n. sp. and three new records of M. adenobia, M. amasactae, and M. rainai (Nematoda: Rhabditidae) were found from Sindh. M. longicaudata n. sp. differed from the species of the genus Metarhabditis by having long uncovered tail spike. It was also characterized by a large sized male 1286 (1154-1325) µm; longer male tail 69.5 (62-76) µm; longer spicule 43 (40-46) µm; leptoderan bursa; longer gubernaculum 27 (20-34) µm. The female was also of large size of 1507 (1366-1684) µm with larger tail 102 (94-112) µm and longer pharynx 231 (206-265) µm. The genus Metarhabditis is reported for the first time from Sindh, Pakistan.

Plant Protection , 2019

A bulk of potato varieties were screened against Phytophthora infestans causing the late blight o... more A bulk of potato varieties were screened against Phytophthora infestans causing the late blight of potato. Almost all the potato germplasm showed a varying response against the devastating pathogen at Okara and Sahiwal. Field trials were consisted of screening of germplasm, area under disease progress curve and chemical management of the disease by using the various fungicides. Randomized complete block design was used for the research at both locations. Out of 68 genotypes/ varieties 16 were susceptible, 20 moderately resistant, five highly susceptible and 27 as moderately susceptible. Maximum disease incidence was recorded on Desiree and Cardinal (90%) followed by Santee (83.33%). The maximum mean disease severity of 9.48 was noted on Cardinal followed by Desiree 9.11 and Karoda 9.0 with the area under disease progress curve 28.55, 27.33 and 26.00 respectively. The results showed that 5gm/ L was the best dose against the suppression and control of the potato late blight under the field conditions. Azoxystrobin which is a new chemistry fungicide found to be the best chemical treatment against the late blight of potato followed by the copper oxychloride-based fungicides Cobox which also showed the best response. Aliette, Antracol, Tebuconazole and Mancozeb were also played a role to minimize the disease yet their higher concentration was even not so effective to combat the disease. Mancozeb was not found to be effective to control the disease as compared to the other three fungicides and orange oil extract.

Plant Protection , 2019

Diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae) is one of the most notorious and... more Diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae) is one of the most notorious and cosmopolitan insect pests of brassica crops around the world. P. xylostella may cause 90% yield losses in brassica crops. Various control measures have been adopted to manage this pest; however, the most effective control method is the use of synthetic chemical insecticides. Overuse of insecticides have many adverse effects including insecticide resistance, hazardous to environment, long persistency, interference with food chain. There is an urgent need for alternative control measures which should be effective, environmental friendly and economically safer. Bio-pesticides include plant extracts and green synthesized nano-based insecticides are among the feasible alternative measures which can be useful for the management of P. xylostella. Less work has been carried out on the use of green synthesized plant products against P. xylostella. Therefore, the current study was planned to evaluate the toxicity of plant extracts and green synthesized nano-based plant products against P. xylostella. Eight plants extracts (neem, bakain, bitter gourd, clove, eucalyptus, dathura, garlic and ginger) and their nano-based products (green synthesis silver nanoparticles) were applied in different concentrations against 3 rd larval instars of P. xylostella. Mortality were recorded after 24, 48 and 72 hours of application of treatments. Corrected mortality was calculated using Abbot's formula and LC50 values were calculated. All the plants extract had great potential to kill the maximum population of diamondback moth at high concentration. All these plants extract gave more than 80% mortality which was at the rate of 23, 24, 20 and 30 mg/ml respectively after 72 hour interval. The present study indicated that the botanical insecticides have good toxic effect against the 3 rd instar larvae of diamondback moth.

Plant Protection , 2019

In Khairpur, dates crop is damaged during rainy months of June, July and August as the rainy seas... more In Khairpur, dates crop is damaged during rainy months of June, July and August as the rainy season provides favorable conditions for most of the microorganisms. Amongst different microorganisms, fungi are known as the severest pathogens. In the present study, phytopathogenic fungi associated with ripening fruits of different varieties of dates (Aseel, Khar and Kupro) were isolated and characterized. Three fungi viz. Aspergillus flavus, Penicillium expansum and Alternaria tenuis were isolated from the ripening fruits of date varieties. The fungus P. expansum was isolated from Kupro, A. tenuis from Aseel and A. flavus from Kupro.

Plant Protection , 2019

Onion is widely cultivated crop and attacked by different fungi. Purple blotch of onion caused by... more Onion is widely cultivated crop and attacked by different fungi. Purple blotch of onion caused by Alternaria porri is a continuous threat to Pakistan agriculture industry for the last few years. Generally, fungicides give satisfactory control but due to the environmental concerns, their use should be restricted. In integrated disease management program, cost effective and eco-friendly approach is used to cope with plant pathogens. Therefore, the present study was planned to evaluate the antifungal efficacy of different plants extracts such as Pongamia pinnata, Polyalthia longifolia, Cassia fistula, and Citrus sinensis against A. porri alone as well as synergistically with different concentrations of Mancozeb under in vitro conditions. Methanolic leaves extracts of these plants were mixed with different concentrations (25, 50, and 75%) of fungicide and screened via poisoned food technique to measure percent inhibition of fungal growth. The results indicated that plant extracts alone gave appreciable amount of fungal reduction but when used in combination with fungicide, performed best. Among them P. longifolia gave 73%inhibition, C. sinensis 49%, P. pinnata 70%and Cassia fistula showed46% inhibition respectively. In combination with fungicide, 25% of recommended dose, P. longifolia gave 82.93%, P. pinnata gave 77.07 %, C. sinensis 73.17% and C. fistula gave 62.92% inhibition as compared to control against A. porri. With the increase of fungicide in combination, more reduction in the fungal growth was observed. It is concluded that extracts can be used synergistically with fungicides. The combinations will protect the environment by reducing the amount of fungicide.

Plant Protection , 2019

Wheat (Triticum aestivum L.) is the leading food grain and staple diet in Pakistan. Cereal aphids... more Wheat (Triticum aestivum L.) is the leading food grain and staple diet in Pakistan. Cereal aphids are a severe problem in wheat growing areas. Among environmentally safe and economical methods for the control of aphids, the use of resistant wheat cultivars is one of the promising approach in pest management programs which can overcome the economic damage caused by aphid infestation. In the present study, the population dynamics of wheat aphid was observed on 114 landraces of wheat. The results showed that during March, nine landraces showed the highest population of Rhopalosiphum padi while the lowest R. padi population was recorded on fourteen different landraces with aphid populations ranging from 3.25 to 4.08. In the month of April, the highest population of R. padi was recorded on 81 landraces while the lowest population was recorded on 33 landraces with mean aphid numbers ranging from 2.91 to 6.9. The peak population was recorded during the month of May on 78 landraces of wheat and proved to be the susceptible while the remaining thirty eight landraces of wheat proved to be resistant with low aphid densities. The mean aphid population varied from 4.25 to 6.95. The results obtained from the month of March were non-significant while those obtained during the months of April and May were significant.

Plant Protection, 2019

Cotton, popularly known as white gold, is the king of natural fiber and an important cash crop of... more Cotton, popularly known as white gold, is the king of natural fiber and an important cash crop of Pakistan which earns foreign exchange up to 11.7% and 2.9% of GDP. The present study was carried out in cotton growing areas of four divisions of Punjab to determine the choice of cotton growers for the selection of pesticides for the management of whitefly. The data of hot spots of whitefly were recorded twice a week from April to October during 2015, 2016 and 2017 by using the standard pest scouting method. The study revealed that an increase of 16.09% hot spots of whitefly was detected in 2017 as compared to previous two consecutive years (2015 and 2016). Regarding farmers’ choice for selection of pesticides used to control whitefly, the farmers used Imidacloprid, Acetamiprid, Buprofezin, Clothinadin, Diafenthiuron, Flonicamid, Matrine, Pyriproxifen, Pymetrozine, Spirotetramat. The comparison of three years indicated that maximum farmers preferred to spray Pyriproxifen on the hot spots of cotton whitefly followed by Buprofezin, Acetamiprid and Diafenthiuronwhile Clothinadin and Matrine were used by the minimum numbers of farmers. The use of these insecticides by the farmers during the three years was non-significant. The farmers preferred these pesticides being of third generation, IGRs, Neonicotinoids, environment friendly to human health and safer to natural enemies of whitefly.

Plant Protection, 2019

Proper identification of wild mushrooms is important to study their biodiversity and ecological r... more Proper identification of wild mushrooms is important to study their biodiversity and ecological role. The discovery of new medicinal mushroom species will lead to their exploitation as an industry. No research work has been done about medicinal mushrooms in Murree hills in the past. Keeping in view the importance of Ganoderma species, the present studies were carried out to determine the distribution and prevalence of Ganoderma species in Murree hills on different host plants. In all, eight species of Ganoderma were identified from Murree hills of Pakistan. Cedrus deodara and Eucalyptus citriodora were found to be the most susceptible hosts of Ganoderma species. The identified species were Ganoderma praelongum, G. chalceum (Eucalyptus citriodora), G. applanatum (Abies pindro), G. curtisii, G. multicornum (Cedrus deodara) G. lipsiense (Acacia arabica), G. multiplicatum (Pinus logifolia) and G. boninense (Morus alba). These identified species were non-mushroom and belonged to Phylum Basidiomycota. Variations were observed among different morphological and cultural properties. The color of the pileus surface was found light to dark brown and one species showed white to creamish color. The maximum length and thickness of pileus was found to be 32 cm and 10 cm respectively. Majority of Ganoderma specimens were lateral, central, stipitate, dimidiate and sessile. Among cultural characteristics, colonies of the Ganoderma species possessed brown color and some were white to creamish. Colonies were circular and smooth to slimy. Most of the species produced the hyphal system trimetic which had the generative and sketal hyphae. Most spores were brown ellipsoid and oval shape. The maximum spore index was 2.5. Maximum tube size of 1 cm and minimum tube size 2 mm were recorded. Pale brown cystidia with thin walls were seen from the germinating cystidia.

Plant Protection, 2019

Okra is a valuable vegetable crop of Pakistan. It is predominantly hosted by pathogens that reduc... more Okra is a valuable vegetable crop of Pakistan. It is predominantly hosted by pathogens that reduce its yield and quality. Among these yield reducing agents, root knot nematodes are very important due to their host rang. Chemical control for this important pathogen is expensive and causes pollution problems so the present study was planned to evaluate the level of resistance among different available varieties of okra against Meloidogyne incognita under field conditions. The selected field was already infested with M. incognita. Data were recorded on various plant growth parameters and nematode development parameters after sixty days. Results indicated that for various nematode populations and plant growth attributes all the cultivars significantly differed with the Sabzpari 2001 and Sabzpari X Ramakrishna having best performance on over all yield by showing moderately resistant response but no variety was resistant against M. incognita. On over all basis and yield attributes, it is recommended that Sabzpari 2001 and Sabzpari X Ramakrishna are moderately resistant to nematode infestation and should be recommended to farmers in root knot nematode infested soils of Pakistan.

Plant Protection, 2019

Chickpea (Cicer arietinum L.) is the world's third most important pulse crop. It belongs to the p... more Chickpea (Cicer arietinum L.) is the world's third most important pulse crop. It belongs to the pea family with short and hairy pods containing usually two seeds. Chickpea is an important high protein crop of "Thal" area in Pakistan having major source of protein in animal feed and human diet especially for low income group, by supplementing their cereal diets. There was a study gap regarding field efficacy of different fungicides being used as seed treatment. To address this deficiency, efficacy of three different fungicides was studied in field against occurrence of gram wilt. The research trial was conducted at the farmer field during gram growing season of 2016-2017. Crop was sown on 20 th of October by adopting standard seed rate, row to row and plant to plant distance, fertilizer and irrigation plan. Observations were recorded on weekly basis from sowing to harvesting of crop and grain yield was also recorded. Results showed that Divind Star 036FS (difenconazole + cyproconazole) @1 ml/ kg of seed is best by minimum disease occurrence with mean of 7.18% compared with 39.26% in control. Although statistically similar results were obtained of all three fungicide treatments with efficacy order of Divind Star 036FS > Teranil 45 DP > Dynasty 125 FS. Divind Star 036FS also proved most effective for better yield followed by Teranil 45 DP (bromothelanil) 5 g/kg of seed with mean of 340.67 and 332.66 g per m² respectively. Control plot showed minimum yield with mean of 193 g/ m². Comparative study of percent germination of gram crop in field after seed treatment with three different fungicides showed that Dynasty 125 FS (ezoxystrobin + fludioxonil + mefenoxam) @ 3 ml/kg of seed was best with maximum mean germination of 78.33% over control.

Plant Protection, 2019

(Solanum tuberosum L.) potato is globally an imperative crop. Various biotic constraints affect i... more (Solanum tuberosum L.) potato is globally an imperative crop. Various biotic constraints affect its yield production and market value. Streptomyces scabies is one of them which reduce the market value besides meet the requirements for the rhizomes. The affect findings were conducted to appraise the pathogenic variation, pathogenicity, morphological and biochemical depiction of Streptomyces species linked by potato tubers grown-up happening Poonch (district). Disease incidence index and variation in pathogenic data of disease be there is being cultivated by means of utilizing various inclusion in addition to the techniques of characterization. Test of Pathogenicity remained indicated that all insulates stayed pathogenic on all cultivar causing indications using assertiveness of straining to fluctuate starting slightly to discreetly function.

Plant Protection , 2019

Sonchus asper (annual sow thistle) is an annual or winter annual herbaceous plant native to Europ... more Sonchus asper (annual sow thistle) is an annual or winter annual herbaceous plant native to Europe. It has become a very aggressive invader in many regions of the world. In February 2013, S. asper plants grown in and around the chickpea and tomato fields at Nuclear Institute for Agriculture and Biology (NIAB), Faisalabad, Pakistan were found to be severely affected by a leaf blight disease. Initially the disease symptoms began as small, circular, dark, necrotic lesions usually on the older leaves. At later stage, these lesions enlarged rapidly up to 4-12 mm in diameter and when spotting was abundant the entire leaf turned yellow. However, in April 2013, S. asper plants grown in and around the tomato and wheat fields at NIAB, Faisalabad, Pakistan were found with different leaf blight symptoms. The leaf spots were initially small, epiphyllous, irregular, scattered to marginal and dark-brown. Later on these spots enlarged, became orbicular to irregular but often angular, with brown to cinereous necrotic centers and usually with a narrow dark margin. On the basis of symptoms, morphological and cultural characteristics of the isolated pathogen, the causal agent was identified as Alternaria alternata from February infected plants while it was identified as Alternaria sonchi from April infected plants and Koch’s postulates were fulfilled. This is the first report of Alternaria alternata and Alternaria sonchi from S. asper plants in Pakistan.

Plant Protection , 2019

Field studies on the efficacy of bio-control agents (lacewing and Trichograma) in the management ... more Field studies on the efficacy of bio-control agents (lacewing and Trichograma) in the management of okra pests were carried out at the trial area of Entomology Section, Agriculture Research Institute, Tando Jam. Seeds of okra (Subz pari) were sown on 7 th February 2017 in a complete randomized block design with three replications. The biocontrol agents, lacewing and Trichogramma (1300 eggs/card) each were released. Lacewing was found very effective against aphid, jassid and whitefly in the field. Aphid was found at early stage of crop and touched the maximum level in mid-February, therefore its population decreased quickly. Jassid increased linearly and was high after 6 th week of observation and then decreased subsequently till picking of the crop. On the other hand, whitefly population increased linearly till 9 th week of observation and then decreased and eventually disappeared from the crop on 19 th week of observation. Trichogramma was observed as a main natural enemy of spotted bollworm of okra and reduced bollworm population. The population of bollworm increased slowly till harvesting of the crop. It is concluded from the present study that both the bio-control agents successfully lowered the populations of sucking and chewing insect pests and bollworms of okra. Lacewing was found effective against sucking insect pests while Trichogram efficiently controlled bollworms and are recommended for field applications. These bio-control agents can also be incorporated in IPM strategy.

Plant Protection, 2019

Charcoal rot is one of the major threats to sunflower which causes complete crop loss in epidemic... more Charcoal rot is one of the major threats to sunflower which causes complete crop loss in epidemic conditions. The genetic resistance of sunflower germplasm could be more economical and durable approach for the management of charcoal rot. In the current experiment, six genotypes obtained from Ayub Agricultural Research Institute, Faisalabad were evaluated for their resistance and morphological parameters against Macrophomina phaseolina. Under field conditions, none of the cultivars gave immune or resistant response against the disease. FH-337 was found to be susceptible with 54.87% infection while FH-331, FH-106 and Hycanth-33 appeared moderately susceptible with 25-49% infections. The least affected varieties were FH-259 and DK-40 with moderately resistant status in the range of 10-24%. Yield parameters of resistant varieties were better than susceptible ones when compared under inoculated conditions. Moderately resistant genotypes might have the better genetic makeup and could be selected in breeding programs to find out resistant sunflower germplasm to fulfill the needs of growing population. Moreover, these cultivars could be used for better yield of sunflower.

Plant Protection, 2019

The present study was designed to determine the LC50 of some insecticides commonly used against H... more The present study was designed to determine the LC50 of some insecticides commonly used against Helicoverpa armigera and their comparative efficacy against the insect pest. The second instar larvae of H. armigera reared in the laboratory were selected for leaf dip bioassay. Two types of insecticides viz. conventional (deltamethrin and bifenthrin) and new chemistry (spinosad and indoxacarb) were assessed in the present studies. The results revealed that bifenthrin was more toxic to the second instar larvae of H. armigera at all the doses with lower LC50 value of 120.007 ppm as compared to deltamethrin with the highest LC50 value of 292.404 ppm. Among the new chemistry insecticides, indoxacarb proved to be more toxic than spinosad with LC50 of 5.592 ppm. LC50 of spinosad was 8.201 ppm showing 1.46 times less toxicity than indoxacarb.

Plant Protection, 2019

The family Acridoidea of the order Orthoptera comprised of insects including grasshoppers, cricke... more The family Acridoidea of the order Orthoptera comprised of insects including grasshoppers, crickets and locusts with paurometabolous type metamorphosis. The present work reports about the studies on the epiphallus and spermatheca in some species of the genus Acrotylus (Acridoidea: Orthoptera) of Pakistan. The species included Acrotylus humbertianus (Saussure), A. insubricus insubricus (Scopoli) A. patruelis (Herrich-Schaffer) A. longipes longipes (Charpentier) and A. longipes subfasciatus. The spermatheca is an organ playing a key role in insect reproduction allowing the storage of spermatozoa and making them available when needed. Moreover, there is information about the genitalia of these grasshoppers. In the present studies, observations were made on the diagnostic characters of epiphallus and spermatheca that have been useful for the purpose of accurate identification. Epiphallus varied in these species i.e. moderately wide bridge, narrow ancorae and bilobate lophi. Similarly, spermatheca was found of varying sizes and shapes. The spermatheca well dilates to form a sac like structure, for storing the spermatozoa which enter during copulation. The characteristics can be used for the accurate identification of Acrotylus species.

Plant Protection , 2019

The current research was planned to evaluate the response of 37 wheat (Triticum aestivum) genotyp... more The current research was planned to evaluate the response of 37 wheat (Triticum aestivum) genotypes against leaf rust resistance under field conditions during 2017-18. Areas under disease progress curve (AUDPC) of all the varieties were calculated. Leaf rust severity response was variable among the tested genotypes. Out of thirty-seven genotypes, five wheat lines i.e. 17BT007, 17BT013, 16BT008, 16BT010 and 16BT011 were immune. Seven lines were found to be resistant with AUDPC values ranged from 1 to 199. Response of ten lines was moderately resistant while five lines were categorized as moderately susceptible. Ten genotypes exhibited susceptible response against leaf rust with more than 600 AUDPC value. High values above 600 of AUDPC showed greater incidence of leaf rust on wheat plants while lower AUDPC values indicated resistance to leaf rust. Present research provided the resistant wheat lines to the breeders to incorporate in their breeding program against leaf rust.

Plant Protection , 2019

Malakand Division in northwest Pakistan is known for delicious sweet orange, locally called Malta... more Malakand Division in northwest Pakistan is known for delicious sweet orange, locally called Malta (Citrus sinensis). However, both quality and quantity of the citrus produce has seen a decline over the past few decades. Among production constraints, Huanglongbing (HLB) caused by phloem-limited alpha proteobacterium Candidatus Liberibacter asiaticus (CLas) -an endosymbiont of Asian Citrus Psyllid (Diaphorina citri), is of great economic significance. Therefore, we assessed HLB incidence through symptom-based surveys in major citrus growing areas of Khyber Pakhtunkhwa (KP), Northwest Pakistan. The presence or absence of CLas in the collected citrus samples was confirmed by PCR (Polymerase Chain Reaction) using three set of primers (LSS/LAS606, OI1/OI2C “16S rDNA” and MH353/MH354 “operon “nusG-rplK”). An average disease incidence of 92% and severity of 34% were recorded from main production zones in district Swat, KP. Likewise, in district Lower Dir, HLB had disease incidence and severity of 64% and 24%, respectively. Molecular diagnostics using 16S rDNA-specific primer LSS/LAS606 and OI1/OI2C, yielded characteristic bands of 500 bp and 1160 bp, from all five pooled samples from Swat district, while only two samples of Dir tested positive for both primers. Using an alternative primer MH353/MH354 (nusG-rplK) showed positive amplification for four samples from Swat and two samples of Dir with an amplicon of 631 bp. To assess the molecular diversity of the CLas, Sanger sequencing was carried out based on16S rDNA gene. Sequence analysis of 16S rDNA gene from all samples revealed maximum similarity with C. Liberibacter asiaticus. Among studied isolates, SwKjuPk-5 (MH374503) and SwMtaPk-2 (MH374500) isolates appeared to be more divergent and grouped in separate clad as compared to remaining isolates of Swat and Dir.

Plant Protection , 2019

Quinoa (Chenopodium quinoa L.) is a recently introduced pseudocereal crop in Pakistan. In the pre... more Quinoa (Chenopodium quinoa L.) is a recently introduced pseudocereal crop in Pakistan. In the present study, methanolic extract was partitioned with n-hexane, chloroform and finally with ethyl acetate. The ethyl acetate fraction was subjected to GC-MS analysis for the identification of various antimicrobial and antioxidant constituents. Thirteen compounds were identified through GC-MS analysis of this fraction. Among these, 11 compounds possessed antibacterial, antifungal and/or antioxidant properties as reported in literature. These include naphthalene; tetradecane; hexadecane; pentadecane; cyclohexadecane; 1,2-benzenedicarboxylic acid, bis(2-methylpropyl) ester; dibutyl phthalate; 1-nonadecene; 1-octadecanol; 9-hexacosene; and 1,2-benzenedicarboxylic acid, mono(2-ethylhexyl) ester.

Plant Protection , 2019

Many rhabditid nematodes like Metarhabditis belonging to the bacteriophage group are considered t... more Many rhabditid nematodes like Metarhabditis belonging to the bacteriophage group are considered to be necromenic associates of insects and used to be facultative entomopathogenic nematodes or as biocontrol agents. These nematodes can be safely used against insect pests of different crops and vegetables. In the present study, nematode specimens of new and known species were collected from different areas of Sindh and isolated from soil samples by baiting technique using last instar Galleria mellonella. One new nematode species Metarhabditis longicaudata n. sp. and three new records of M. adenobia, M. amasactae, and M. rainai (Nematoda: Rhabditidae) were found from Sindh. M. longicaudata n. sp. differed from the species of the genus Metarhabditis by having long uncovered tail spike. It was also characterized by a large sized male 1286 (1154-1325) µm; longer male tail 69.5 (62-76) µm; longer spicule 43 (40-46) µm; leptoderan bursa; longer gubernaculum 27 (20-34) µm. The female was also of large size of 1507 (1366-1684) µm with larger tail 102 (94-112) µm and longer pharynx 231 (206-265) µm. The genus Metarhabditis is reported for the first time from Sindh, Pakistan.

Plant Protection , 2019

A bulk of potato varieties were screened against Phytophthora infestans causing the late blight o... more A bulk of potato varieties were screened against Phytophthora infestans causing the late blight of potato. Almost all the potato germplasm showed a varying response against the devastating pathogen at Okara and Sahiwal. Field trials were consisted of screening of germplasm, area under disease progress curve and chemical management of the disease by using the various fungicides. Randomized complete block design was used for the research at both locations. Out of 68 genotypes/ varieties 16 were susceptible, 20 moderately resistant, five highly susceptible and 27 as moderately susceptible. Maximum disease incidence was recorded on Desiree and Cardinal (90%) followed by Santee (83.33%). The maximum mean disease severity of 9.48 was noted on Cardinal followed by Desiree 9.11 and Karoda 9.0 with the area under disease progress curve 28.55, 27.33 and 26.00 respectively. The results showed that 5gm/ L was the best dose against the suppression and control of the potato late blight under the field conditions. Azoxystrobin which is a new chemistry fungicide found to be the best chemical treatment against the late blight of potato followed by the copper oxychloride-based fungicides Cobox which also showed the best response. Aliette, Antracol, Tebuconazole and Mancozeb were also played a role to minimize the disease yet their higher concentration was even not so effective to combat the disease. Mancozeb was not found to be effective to control the disease as compared to the other three fungicides and orange oil extract.

Plant Protection , 2019

Diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae) is one of the most notorious and... more Diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae) is one of the most notorious and cosmopolitan insect pests of brassica crops around the world. P. xylostella may cause 90% yield losses in brassica crops. Various control measures have been adopted to manage this pest; however, the most effective control method is the use of synthetic chemical insecticides. Overuse of insecticides have many adverse effects including insecticide resistance, hazardous to environment, long persistency, interference with food chain. There is an urgent need for alternative control measures which should be effective, environmental friendly and economically safer. Bio-pesticides include plant extracts and green synthesized nano-based insecticides are among the feasible alternative measures which can be useful for the management of P. xylostella. Less work has been carried out on the use of green synthesized plant products against P. xylostella. Therefore, the current study was planned to evaluate the toxicity of plant extracts and green synthesized nano-based plant products against P. xylostella. Eight plants extracts (neem, bakain, bitter gourd, clove, eucalyptus, dathura, garlic and ginger) and their nano-based products (green synthesis silver nanoparticles) were applied in different concentrations against 3 rd larval instars of P. xylostella. Mortality were recorded after 24, 48 and 72 hours of application of treatments. Corrected mortality was calculated using Abbot's formula and LC50 values were calculated. All the plants extract had great potential to kill the maximum population of diamondback moth at high concentration. All these plants extract gave more than 80% mortality which was at the rate of 23, 24, 20 and 30 mg/ml respectively after 72 hour interval. The present study indicated that the botanical insecticides have good toxic effect against the 3 rd instar larvae of diamondback moth.

Plant Protection , 2019

In Khairpur, dates crop is damaged during rainy months of June, July and August as the rainy seas... more In Khairpur, dates crop is damaged during rainy months of June, July and August as the rainy season provides favorable conditions for most of the microorganisms. Amongst different microorganisms, fungi are known as the severest pathogens. In the present study, phytopathogenic fungi associated with ripening fruits of different varieties of dates (Aseel, Khar and Kupro) were isolated and characterized. Three fungi viz. Aspergillus flavus, Penicillium expansum and Alternaria tenuis were isolated from the ripening fruits of date varieties. The fungus P. expansum was isolated from Kupro, A. tenuis from Aseel and A. flavus from Kupro.

Plant Protection , 2019

Onion is widely cultivated crop and attacked by different fungi. Purple blotch of onion caused by... more Onion is widely cultivated crop and attacked by different fungi. Purple blotch of onion caused by Alternaria porri is a continuous threat to Pakistan agriculture industry for the last few years. Generally, fungicides give satisfactory control but due to the environmental concerns, their use should be restricted. In integrated disease management program, cost effective and eco-friendly approach is used to cope with plant pathogens. Therefore, the present study was planned to evaluate the antifungal efficacy of different plants extracts such as Pongamia pinnata, Polyalthia longifolia, Cassia fistula, and Citrus sinensis against A. porri alone as well as synergistically with different concentrations of Mancozeb under in vitro conditions. Methanolic leaves extracts of these plants were mixed with different concentrations (25, 50, and 75%) of fungicide and screened via poisoned food technique to measure percent inhibition of fungal growth. The results indicated that plant extracts alone gave appreciable amount of fungal reduction but when used in combination with fungicide, performed best. Among them P. longifolia gave 73%inhibition, C. sinensis 49%, P. pinnata 70%and Cassia fistula showed46% inhibition respectively. In combination with fungicide, 25% of recommended dose, P. longifolia gave 82.93%, P. pinnata gave 77.07 %, C. sinensis 73.17% and C. fistula gave 62.92% inhibition as compared to control against A. porri. With the increase of fungicide in combination, more reduction in the fungal growth was observed. It is concluded that extracts can be used synergistically with fungicides. The combinations will protect the environment by reducing the amount of fungicide.

Plant Protection , 2019

Wheat (Triticum aestivum L.) is the leading food grain and staple diet in Pakistan. Cereal aphids... more Wheat (Triticum aestivum L.) is the leading food grain and staple diet in Pakistan. Cereal aphids are a severe problem in wheat growing areas. Among environmentally safe and economical methods for the control of aphids, the use of resistant wheat cultivars is one of the promising approach in pest management programs which can overcome the economic damage caused by aphid infestation. In the present study, the population dynamics of wheat aphid was observed on 114 landraces of wheat. The results showed that during March, nine landraces showed the highest population of Rhopalosiphum padi while the lowest R. padi population was recorded on fourteen different landraces with aphid populations ranging from 3.25 to 4.08. In the month of April, the highest population of R. padi was recorded on 81 landraces while the lowest population was recorded on 33 landraces with mean aphid numbers ranging from 2.91 to 6.9. The peak population was recorded during the month of May on 78 landraces of wheat and proved to be the susceptible while the remaining thirty eight landraces of wheat proved to be resistant with low aphid densities. The mean aphid population varied from 4.25 to 6.95. The results obtained from the month of March were non-significant while those obtained during the months of April and May were significant.

Plant Protection, 2019

Cotton, popularly known as white gold, is the king of natural fiber and an important cash crop of... more Cotton, popularly known as white gold, is the king of natural fiber and an important cash crop of Pakistan which earns foreign exchange up to 11.7% and 2.9% of GDP. The present study was carried out in cotton growing areas of four divisions of Punjab to determine the choice of cotton growers for the selection of pesticides for the management of whitefly. The data of hot spots of whitefly were recorded twice a week from April to October during 2015, 2016 and 2017 by using the standard pest scouting method. The study revealed that an increase of 16.09% hot spots of whitefly was detected in 2017 as compared to previous two consecutive years (2015 and 2016). Regarding farmers’ choice for selection of pesticides used to control whitefly, the farmers used Imidacloprid, Acetamiprid, Buprofezin, Clothinadin, Diafenthiuron, Flonicamid, Matrine, Pyriproxifen, Pymetrozine, Spirotetramat. The comparison of three years indicated that maximum farmers preferred to spray Pyriproxifen on the hot spots of cotton whitefly followed by Buprofezin, Acetamiprid and Diafenthiuronwhile Clothinadin and Matrine were used by the minimum numbers of farmers. The use of these insecticides by the farmers during the three years was non-significant. The farmers preferred these pesticides being of third generation, IGRs, Neonicotinoids, environment friendly to human health and safer to natural enemies of whitefly.

Plant Protection, 2019

Proper identification of wild mushrooms is important to study their biodiversity and ecological r... more Proper identification of wild mushrooms is important to study their biodiversity and ecological role. The discovery of new medicinal mushroom species will lead to their exploitation as an industry. No research work has been done about medicinal mushrooms in Murree hills in the past. Keeping in view the importance of Ganoderma species, the present studies were carried out to determine the distribution and prevalence of Ganoderma species in Murree hills on different host plants. In all, eight species of Ganoderma were identified from Murree hills of Pakistan. Cedrus deodara and Eucalyptus citriodora were found to be the most susceptible hosts of Ganoderma species. The identified species were Ganoderma praelongum, G. chalceum (Eucalyptus citriodora), G. applanatum (Abies pindro), G. curtisii, G. multicornum (Cedrus deodara) G. lipsiense (Acacia arabica), G. multiplicatum (Pinus logifolia) and G. boninense (Morus alba). These identified species were non-mushroom and belonged to Phylum Basidiomycota. Variations were observed among different morphological and cultural properties. The color of the pileus surface was found light to dark brown and one species showed white to creamish color. The maximum length and thickness of pileus was found to be 32 cm and 10 cm respectively. Majority of Ganoderma specimens were lateral, central, stipitate, dimidiate and sessile. Among cultural characteristics, colonies of the Ganoderma species possessed brown color and some were white to creamish. Colonies were circular and smooth to slimy. Most of the species produced the hyphal system trimetic which had the generative and sketal hyphae. Most spores were brown ellipsoid and oval shape. The maximum spore index was 2.5. Maximum tube size of 1 cm and minimum tube size 2 mm were recorded. Pale brown cystidia with thin walls were seen from the germinating cystidia.

Plant Protection, 2019

Okra is a valuable vegetable crop of Pakistan. It is predominantly hosted by pathogens that reduc... more Okra is a valuable vegetable crop of Pakistan. It is predominantly hosted by pathogens that reduce its yield and quality. Among these yield reducing agents, root knot nematodes are very important due to their host rang. Chemical control for this important pathogen is expensive and causes pollution problems so the present study was planned to evaluate the level of resistance among different available varieties of okra against Meloidogyne incognita under field conditions. The selected field was already infested with M. incognita. Data were recorded on various plant growth parameters and nematode development parameters after sixty days. Results indicated that for various nematode populations and plant growth attributes all the cultivars significantly differed with the Sabzpari 2001 and Sabzpari X Ramakrishna having best performance on over all yield by showing moderately resistant response but no variety was resistant against M. incognita. On over all basis and yield attributes, it is recommended that Sabzpari 2001 and Sabzpari X Ramakrishna are moderately resistant to nematode infestation and should be recommended to farmers in root knot nematode infested soils of Pakistan.

Plant Protection, 2019

Chickpea (Cicer arietinum L.) is the world's third most important pulse crop. It belongs to the p... more Chickpea (Cicer arietinum L.) is the world's third most important pulse crop. It belongs to the pea family with short and hairy pods containing usually two seeds. Chickpea is an important high protein crop of "Thal" area in Pakistan having major source of protein in animal feed and human diet especially for low income group, by supplementing their cereal diets. There was a study gap regarding field efficacy of different fungicides being used as seed treatment. To address this deficiency, efficacy of three different fungicides was studied in field against occurrence of gram wilt. The research trial was conducted at the farmer field during gram growing season of 2016-2017. Crop was sown on 20 th of October by adopting standard seed rate, row to row and plant to plant distance, fertilizer and irrigation plan. Observations were recorded on weekly basis from sowing to harvesting of crop and grain yield was also recorded. Results showed that Divind Star 036FS (difenconazole + cyproconazole) @1 ml/ kg of seed is best by minimum disease occurrence with mean of 7.18% compared with 39.26% in control. Although statistically similar results were obtained of all three fungicide treatments with efficacy order of Divind Star 036FS > Teranil 45 DP > Dynasty 125 FS. Divind Star 036FS also proved most effective for better yield followed by Teranil 45 DP (bromothelanil) 5 g/kg of seed with mean of 340.67 and 332.66 g per m² respectively. Control plot showed minimum yield with mean of 193 g/ m². Comparative study of percent germination of gram crop in field after seed treatment with three different fungicides showed that Dynasty 125 FS (ezoxystrobin + fludioxonil + mefenoxam) @ 3 ml/kg of seed was best with maximum mean germination of 78.33% over control.

Plant Protection, 2019

(Solanum tuberosum L.) potato is globally an imperative crop. Various biotic constraints affect i... more (Solanum tuberosum L.) potato is globally an imperative crop. Various biotic constraints affect its yield production and market value. Streptomyces scabies is one of them which reduce the market value besides meet the requirements for the rhizomes. The affect findings were conducted to appraise the pathogenic variation, pathogenicity, morphological and biochemical depiction of Streptomyces species linked by potato tubers grown-up happening Poonch (district). Disease incidence index and variation in pathogenic data of disease be there is being cultivated by means of utilizing various inclusion in addition to the techniques of characterization. Test of Pathogenicity remained indicated that all insulates stayed pathogenic on all cultivar causing indications using assertiveness of straining to fluctuate starting slightly to discreetly function.

Plant Protection , 2019

Sonchus asper (annual sow thistle) is an annual or winter annual herbaceous plant native to Europ... more Sonchus asper (annual sow thistle) is an annual or winter annual herbaceous plant native to Europe. It has become a very aggressive invader in many regions of the world. In February 2013, S. asper plants grown in and around the chickpea and tomato fields at Nuclear Institute for Agriculture and Biology (NIAB), Faisalabad, Pakistan were found to be severely affected by a leaf blight disease. Initially the disease symptoms began as small, circular, dark, necrotic lesions usually on the older leaves. At later stage, these lesions enlarged rapidly up to 4-12 mm in diameter and when spotting was abundant the entire leaf turned yellow. However, in April 2013, S. asper plants grown in and around the tomato and wheat fields at NIAB, Faisalabad, Pakistan were found with different leaf blight symptoms. The leaf spots were initially small, epiphyllous, irregular, scattered to marginal and dark-brown. Later on these spots enlarged, became orbicular to irregular but often angular, with brown to cinereous necrotic centers and usually with a narrow dark margin. On the basis of symptoms, morphological and cultural characteristics of the isolated pathogen, the causal agent was identified as Alternaria alternata from February infected plants while it was identified as Alternaria sonchi from April infected plants and Koch’s postulates were fulfilled. This is the first report of Alternaria alternata and Alternaria sonchi from S. asper plants in Pakistan.

Plant Protection , 2019

Field studies on the efficacy of bio-control agents (lacewing and Trichograma) in the management ... more Field studies on the efficacy of bio-control agents (lacewing and Trichograma) in the management of okra pests were carried out at the trial area of Entomology Section, Agriculture Research Institute, Tando Jam. Seeds of okra (Subz pari) were sown on 7 th February 2017 in a complete randomized block design with three replications. The biocontrol agents, lacewing and Trichogramma (1300 eggs/card) each were released. Lacewing was found very effective against aphid, jassid and whitefly in the field. Aphid was found at early stage of crop and touched the maximum level in mid-February, therefore its population decreased quickly. Jassid increased linearly and was high after 6 th week of observation and then decreased subsequently till picking of the crop. On the other hand, whitefly population increased linearly till 9 th week of observation and then decreased and eventually disappeared from the crop on 19 th week of observation. Trichogramma was observed as a main natural enemy of spotted bollworm of okra and reduced bollworm population. The population of bollworm increased slowly till harvesting of the crop. It is concluded from the present study that both the bio-control agents successfully lowered the populations of sucking and chewing insect pests and bollworms of okra. Lacewing was found effective against sucking insect pests while Trichogram efficiently controlled bollworms and are recommended for field applications. These bio-control agents can also be incorporated in IPM strategy.

Plant Protection, 2019

Charcoal rot is one of the major threats to sunflower which causes complete crop loss in epidemic... more Charcoal rot is one of the major threats to sunflower which causes complete crop loss in epidemic conditions. The genetic resistance of sunflower germplasm could be more economical and durable approach for the management of charcoal rot. In the current experiment, six genotypes obtained from Ayub Agricultural Research Institute, Faisalabad were evaluated for their resistance and morphological parameters against Macrophomina phaseolina. Under field conditions, none of the cultivars gave immune or resistant response against the disease. FH-337 was found to be susceptible with 54.87% infection while FH-331, FH-106 and Hycanth-33 appeared moderately susceptible with 25-49% infections. The least affected varieties were FH-259 and DK-40 with moderately resistant status in the range of 10-24%. Yield parameters of resistant varieties were better than susceptible ones when compared under inoculated conditions. Moderately resistant genotypes might have the better genetic makeup and could be selected in breeding programs to find out resistant sunflower germplasm to fulfill the needs of growing population. Moreover, these cultivars could be used for better yield of sunflower.

Plant Protection, 2019

The present study was designed to determine the LC50 of some insecticides commonly used against H... more The present study was designed to determine the LC50 of some insecticides commonly used against Helicoverpa armigera and their comparative efficacy against the insect pest. The second instar larvae of H. armigera reared in the laboratory were selected for leaf dip bioassay. Two types of insecticides viz. conventional (deltamethrin and bifenthrin) and new chemistry (spinosad and indoxacarb) were assessed in the present studies. The results revealed that bifenthrin was more toxic to the second instar larvae of H. armigera at all the doses with lower LC50 value of 120.007 ppm as compared to deltamethrin with the highest LC50 value of 292.404 ppm. Among the new chemistry insecticides, indoxacarb proved to be more toxic than spinosad with LC50 of 5.592 ppm. LC50 of spinosad was 8.201 ppm showing 1.46 times less toxicity than indoxacarb.

Plant Protection, 2019

The family Acridoidea of the order Orthoptera comprised of insects including grasshoppers, cricke... more The family Acridoidea of the order Orthoptera comprised of insects including grasshoppers, crickets and locusts with paurometabolous type metamorphosis. The present work reports about the studies on the epiphallus and spermatheca in some species of the genus Acrotylus (Acridoidea: Orthoptera) of Pakistan. The species included Acrotylus humbertianus (Saussure), A. insubricus insubricus (Scopoli) A. patruelis (Herrich-Schaffer) A. longipes longipes (Charpentier) and A. longipes subfasciatus. The spermatheca is an organ playing a key role in insect reproduction allowing the storage of spermatozoa and making them available when needed. Moreover, there is information about the genitalia of these grasshoppers. In the present studies, observations were made on the diagnostic characters of epiphallus and spermatheca that have been useful for the purpose of accurate identification. Epiphallus varied in these species i.e. moderately wide bridge, narrow ancorae and bilobate lophi. Similarly, spermatheca was found of varying sizes and shapes. The spermatheca well dilates to form a sac like structure, for storing the spermatozoa which enter during copulation. The characteristics can be used for the accurate identification of Acrotylus species.

Plant Protection , 2019

The current research was planned to evaluate the response of 37 wheat (Triticum aestivum) genotyp... more The current research was planned to evaluate the response of 37 wheat (Triticum aestivum) genotypes against leaf rust resistance under field conditions during 2017-18. Areas under disease progress curve (AUDPC) of all the varieties were calculated. Leaf rust severity response was variable among the tested genotypes. Out of thirty-seven genotypes, five wheat lines i.e. 17BT007, 17BT013, 16BT008, 16BT010 and 16BT011 were immune. Seven lines were found to be resistant with AUDPC values ranged from 1 to 199. Response of ten lines was moderately resistant while five lines were categorized as moderately susceptible. Ten genotypes exhibited susceptible response against leaf rust with more than 600 AUDPC value. High values above 600 of AUDPC showed greater incidence of leaf rust on wheat plants while lower AUDPC values indicated resistance to leaf rust. Present research provided the resistant wheat lines to the breeders to incorporate in their breeding program against leaf rust.