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Kerala Agricultural University, Thrissur
The history of agricultural education in Kerala can be traced back to the year 1896 when a scheme was evolved in the erstwhile Travancore State to train a few young men in scientific agriculture at the Demonstration Farm, Karamana, Thiruvananthapuram, presently, the Cropping Systems Research Centre under Kerala Agricultural University. Agriculture was introduced as an optional subject in the middle school classes in the State in 1922 when an Agricultural Middle School was started at Aluva, Ernakulam District. The popularity and usefulness of this school led to the starting of similar institutions at Kottarakkara and Konni in 1928 and 1931 respectively.
Agriculture was later introduced as an optional subject for Intermediate Course in 1953. In 1955, the erstwhile Government of Travancore-Cochin started the Agricultural College and Research Institute at Vellayani, Thiruvananthapuram and the College of Veterinary and Animal Sciences at Mannuthy, Thrissur for imparting higher education in agricultural and veterinary sciences, respectively. These institutions were brought under the direct administrative control of the Department of Agriculture and the Department of Animal Husbandry, respectively. With the formation of Kerala State in 1956, these two colleges were affiliated to the University of Kerala. The post-graduate programmes leading to M.Sc. (Ag), M.V.Sc. and Ph.D. degrees were started in 1961, 1962 and 1965 respectively.
On the recommendation of the Second National Education Commission (1964-66) headed by Dr. D.S. Kothari, the then Chairman of the University Grants Commission, one Agricultural University in each State was established. The State Agricultural Universities (SAUs) were established in India as an integral part of the National Agricultural Research System to give the much needed impetus to Agriculture Education and Research in the Country. As a result the Kerala Agricultural University (KAU) was established on 24th February 1971 by virtue of the Act 33 of 1971 and started functioning on 1st February 1972. The Kerala Agricultural University is the 15th in the series of the SAUs.
In accordance with the provisions of KAU Act of 1971, the Agricultural College and Research Institute at Vellayani, and the College of Veterinary and Animal Sciences, Mannuthy, were brought under the Kerala Agricultural University. In addition, twenty one agricultural and animal husbandry research stations were also transferred to the KAU for taking up research and extension programmes on various crops, animals, birds, etc.
During 2011, Kerala Agricultural University was trifurcated into Kerala Veterinary and Animal Sciences University (KVASU), Kerala University of Fisheries and Ocean Studies (KUFOS) and Kerala Agricultural University (KAU).
Now the University has seven colleges (four Agriculture, one Agricultural Engineering, one Forestry, one Co-operation Banking & Management), six RARSs, seven KVKs, 15 Research Stations and 16 Research and Extension Units under the faculties of Agriculture, Agricultural Engineering and Forestry. In addition, one Academy on Climate Change Adaptation and one Institute of Agricultural Technology offering M.Sc. (Integrated) Climate Change Adaptation and Diploma in Agricultural Sciences respectively are also functioning in Kerala Agricultural University.
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ThesisItem Open Access Mealybugs of vegetable ecosystems and tritrophic interactions of brinjal mealybugs(Department of Agricultural Entomology, College of Agriculture ,Vellayani, 2022) Anitha, N; KAU; Mithra, MohanThe study on “Mealybugs of vegetable ecosystems and tritrophic interactions of brinjal mealybugs” was conducted at College of Agriculture, Vellayani during 2017 to 2020 with the objectives to identify mealybugs and their natural enemy fauna in solanaceous and cucurbitaceous vegetables, to carry out the molecular characterization of mealy bugs in solanaceous and cucurbitaceous vegetables and to find out the tritrophic interactions of mealybugs infesting brinjal. An investigation on mealybug diversity in solanaceous and cucurbitaceous crops of Kerala revealed a total of six mealybug species viz., Coccidohystrix insolita, Ferrisia virgata, Paracoccus marginatus, Phenacoccus solenopsis, Planococcus citri and Pseudococcus jackbeardsleyi. Besides, four mealybugs viz., Crisicoccus hirsutus, Maconellicoccus hirsutus, Planococcus lilacinus and Rastrococcus iceryoides infesting other vegetable crops were also recorded from Kerala. The study also revealed that the population of mealybug, C. insolita collected from different regions of Kerala exhibited significant morphological variation. The molecular characterization studies proved that the population belongs to C. insolita and the variations may be environmental induced. An exploration of the host range of mealybugs infesting solanaceous and cucurbitaceous vegetables in Kerala revealed a total of 113 plants under 73 genera belonging to 31 families, out of which 14 plants were recorded as new host reports. A rich natural enemy fauna on mealybugs belongs to five orders viz., Coleoptera, Lepidoptera, Diptera, Neuroptera and Hymenoptera were documented from Kerala. Twenty species of mealybug predators from five different families were recorded, among which the predominant family was Coccinellidae with 16 species under six genera. Among the various predators collected, Cacoxenus sp. was recorded for the first time as a predator of P. jackbeardsleyi. Eleven hymenopteran parasitoids belonging to five families were documented from mealybugs, of which the majority belongs to the family Encyrtidae. Four new host-parasitoid associations were also recorded for the first 288 time. The study also identified six hyperparasitoids under the family Encyrtidae, of which two species were recorded as new report which includes Cheiloneurus sp. and Prochilonerus sp. associated with the mealybug P. solenopsis. The ants associated with mealybugs in different agroecosystems were also investigated and a total of 14 species of ants belonging to nine genera under three subfamilies were recorded, of which the most dominant subfamily was Formicinae followed by Myrmicinae and Dolichoderinae. The present study also revealed 15 new ant-mealybug associations for the first time. The molecular characterization of eight mealybug species was carried out that complemented the morphological identification of species. A total of eight nucleotide sequences were submitted to NCBI GenBank and accession numbers were generated. The sequences were also submitted to BOLD and illustrative barcodes were generated. The barcodes of C. insolita, C. hirsutus and P. jackbeardsleyi were generated for the first time. The diversity of endosymbionts of the mealybug C. insolita was carried out for the first time. The study revealed a total of 15 phyla of endosymbionts on C. insolita, of which Proteobacteria was the predominant one. An experiment was conducted at Instructional Farm, Vellayani to identify the tritrophic interaction in brinjal, C. insolita and its natural enemies. The study revealed that out of the ten brinjal cultivars evaluated, the lowest mean population of mealybugs was observed in Pusa Uttam whereas the hybrid cultivar, Udit recorded the highest number of mealybugs. The lowest mean per cent leaf infestation was recorded in Pusa Purple Long which was statistically on par with Pusa Uttam whereas the hybrid cultivar, Udit was severely damaged by the mealybugs. Among the tested cultivars, Pusa Purple Long was recorded under the group resistant whereas Udit and Haritha were included under the highly susceptible group based on the mean per cent leaf infestation caused by C. insolita. The cultivar Haritha attracted the highest number of predators whereas the maximum mean population of spiders were observed in Pusa Purple Long. 289 The correlation analysis on the mean population of mealy bugs with biophysical parameters revealed that trichome density, length width ratio of leaf and number of branches exhibited a significant positive correlation with mean population of mealybugs. Correlation studies on the mean population of natural enemies with biophysical parameters revealed that plant height exhibited a significant negative correlation whereas leaf thickness and number of branches revealed a non-significant negative correlation with the mean population of natural enemies. Among the biochemical parameters of brinjal cultivars, total phenol content exhibited a significant negative correlation with the mean population of mealybugs whereas total chlorophyll content showed a significant positive correlation. The correlation between biochemical parameters of brinjal cultivars with the mean population of natural enemies revealed that total phenol and carotenoid content exhibited a non-significant negative correlation whereas total protein content, reducing sugar and total chlorophyll content showed a nonsignificant positive correlation. The info-chemical mediated interactions in brinjal cultivars, mealybug and its natural enemies were studied using a multi-armed olfactometer and Y-shaped olfactometer assay. The results revealed that the cultivar Udit attracted the highest number of natural enemy Chrysoperla zastrowii sillemi while the cultivar Pusa Uttam attracted the lowest number. The variation in preference shown by the natural enemies may be related to the difference in volatile compounds emanating from the host cultivar. The GC-MS analysis of the synomonal compounds of the cultivar, Udit revealed a total of eleven compounds whereas the cultivar Pusa Uttam was recorded with a total of five compounds. The Y shaped olfactometer studies revealed that C. zastrowi sillemi adults showed more preference towards the synomonal compounds of mealybug infested plants than that of healthy plant synomonal extracts. On comparing the volatile profile of synomones of mealybug infested and healthy plants revealed that the synomonal extracts of the mealybug infested cultivar Udit comprised of 11 compounds whereas healthy plant synomonal extracts contained nine compounds. 290 The relative response of C. zastrowi sillemi towards the kairomonal compounds of C. insolita was evaluated in a Y tube olfactometer and the results revealed that the highest mean number of adult lacewings were attracted to the kairomonal compounds of mealybug compared to control. The kairomonal extracts of the mealybug comprised of seven compounds and the composition of these hydrocarbons may determine the selectivity of natural enemies towards the preferred host. The present study recorded a total of six mealybug species infesting solanaceous and cucurbitaceous vegetables and its host range, natural enemies and associated ants in different agro ecological regions of Kerala. The molecular characterization studies supported the morphological taxonomy and the sequences were submitted to NCBI Genbank and BOLD. The study also elucidated the interactions mediated by plant traits and info-chemicals in brinjal-mealybugnatural enemy tritrophic systems. The study recorded Pusa Purple Long as resistant cultivar and Udit and Haritha as highly susceptible cultivar to C. insolita. The plant traits viz., trichome density, length width ratio of leaf, number of branches, total phenol content and total chlorophyll content exhibited significant correlation with mean population of mealybugs whereas plant height exhibited significant correlation with mean population of natural enemies. The study on info-chemical mediated tritrophic interactions revealed that the concentration and composition of volatile compounds determine the differential selectivity of natural enemies. The volatile compounds identified in this study can also be used as a cue in moderating the behavior of natural enemies in the ecosystems. So a thorough knowledge on the tritrophic relations in the ecosystem will aid in manipulating these interactions to devise a better pest management strategy.ThesisItem Open Access Mealybugs of vegetable ecosystems and tritrophic interactions of brinjal mealybugs(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2022) Mithra, Mohan; KAU; Anitha, NThe study on “Mealybugs of vegetable ecosystems and tritrophic interactions of brinjal mealybugs” was conducted at College of Agriculture, Vellayani during 2017 to 2020 with the objectives to identify mealybugs and their natural enemy fauna in solanaceous and cucurbitaceous vegetables, to carry out the molecular characterization of mealy bugs in solanaceous and cucurbitaceous vegetables and to find out the tritrophic interactions of mealybugs infesting brinjal. An investigation on mealybug diversity in solanaceous and cucurbitaceous crops of Kerala revealed a total of six mealybug species viz., Coccidohystrix insolita, Ferrisia virgata, Paracoccus marginatus, Phenacoccus solenopsis, Planococcus citri and Pseudococcus jackbeardsleyi. Besides, four mealybugs viz., Crisicoccus hirsutus, Maconellicoccus hirsutus, Planococcus lilacinus and Rastrococcus iceryoides infesting other vegetable crops were also recorded from Kerala. The study also revealed that the population of mealybug, C. insolita collected from different regions of Kerala exhibited significant morphological variation. The molecular characterization studies proved that the population belongs to C. insolita and the variations may be environmental induced. An exploration of the host range of mealybugs infesting solanaceous and cucurbitaceous vegetables in Kerala revealed a total of 113 plants under 73 genera belonging to 31 families, out of which 14 plants were recorded as new host reports. A rich natural enemy fauna on mealybugs belongs to five orders viz., Coleoptera, Lepidoptera, Diptera, Neuroptera and Hymenoptera were documented from Kerala. Twenty species of mealybug predators from five different families were recorded, among which the predominant family was Coccinellidae with 16 species under six genera. Among the various predators collected, Cacoxenus sp. was recorded for the first time as a predator of P. jackbeardsleyi. Eleven hymenopteran parasitoids belonging to five families were documented from mealybugs, of which the majority belongs to the family Encyrtidae. Four new host-parasitoid associations were also recorded for the first 288 time. The study also identified six hyperparasitoids under the family Encyrtidae, of which two species were recorded as new report which includes Cheiloneurus sp. and Prochilonerus sp. associated with the mealybug P. solenopsis. The ants associated with mealybugs in different agroecosystems were also investigated and a total of 14 species of ants belonging to nine genera under three subfamilies were recorded, of which the most dominant subfamily was Formicinae followed by Myrmicinae and Dolichoderinae. The present study also revealed 15 new ant-mealybug associations for the first time. The molecular characterization of eight mealybug species was carried out that complemented the morphological identification of species. A total of eight nucleotide sequences were submitted to NCBI GenBank and accession numbers were generated. The sequences were also submitted to BOLD and illustrative barcodes were generated. The barcodes of C. insolita, C. hirsutus and P. jackbeardsleyi were generated for the first time. The diversity of endosymbionts of the mealybug C. insolita was carried out for the first time. The study revealed a total of 15 phyla of endosymbionts on C. insolita, of which Proteobacteria was the predominant one. An experiment was conducted at Instructional Farm, Vellayani to identify the tritrophic interaction in brinjal, C. insolita and its natural enemies. The study revealed that out of the ten brinjal cultivars evaluated, the lowest mean population of mealybugs was observed in Pusa Uttam whereas the hybrid cultivar, Udit recorded the highest number of mealybugs. The lowest mean per cent leaf infestation was recorded in Pusa Purple Long which was statistically on par with Pusa Uttam whereas the hybrid cultivar, Udit was severely damaged by the mealybugs. Among the tested cultivars, Pusa Purple Long was recorded under the group resistant whereas Udit and Haritha were included under the highly susceptible group based on the mean per cent leaf infestation caused by C. insolita. The cultivar Haritha attracted the highest number of predators whereas the maximum mean population of spiders were observed in Pusa Purple Long. 289 The correlation analysis on the mean population of mealy bugs with biophysical parameters revealed that trichome density, length width ratio of leaf and number of branches exhibited a significant positive correlation with mean population of mealybugs. Correlation studies on the mean population of natural enemies with biophysical parameters revealed that plant height exhibited a significant negative correlation whereas leaf thickness and number of branches revealed a non-significant negative correlation with the mean population of natural enemies. Among the biochemical parameters of brinjal cultivars, total phenol content exhibited a significant negative correlation with the mean population of mealybugs whereas total chlorophyll content showed a significant positive correlation. The correlation between biochemical parameters of brinjal cultivars with the mean population of natural enemies revealed that total phenol and carotenoid content exhibited a non-significant negative correlation whereas total protein content, reducing sugar and total chlorophyll content showed a nonsignificant positive correlation. The info-chemical mediated interactions in brinjal cultivars, mealybug and its natural enemies were studied using a multi-armed olfactometer and Y-shaped olfactometer assay. The results revealed that the cultivar Udit attracted the highest number of natural enemy Chrysoperla zastrowii sillemi while the cultivar Pusa Uttam attracted the lowest number. The variation in preference shown by the natural enemies may be related to the difference in volatile compounds emanating from the host cultivar. The GC-MS analysis of the synomonal compounds of the cultivar, Udit revealed a total of eleven compounds whereas the cultivar Pusa Uttam was recorded with a total of five compounds. The Y shaped olfactometer studies revealed that C. zastrowi sillemi adults showed more preference towards the synomonal compounds of mealybug infested plants than that of healthy plant synomonal extracts. On comparing the volatile profile of synomones of mealybug infested and healthy plants revealed that the synomonal extracts of the mealybug infested cultivar Udit comprised of 11 compounds whereas healthy plant synomonal extracts contained nine compounds. 290 The relative response of C. zastrowi sillemi towards the kairomonal compounds of C. insolita was evaluated in a Y tube olfactometer and the results revealed that the highest mean number of adult lacewings were attracted to the kairomonal compounds of mealybug compared to control. The kairomonal extracts of the mealybug comprised of seven compounds and the composition of these hydrocarbons may determine the selectivity of natural enemies towards the preferred host. The present study recorded a total of six mealybug species infesting solanaceous and cucurbitaceous vegetables and its host range, natural enemies and associated ants in different agro ecological regions of Kerala. The molecular characterization studies supported the morphological taxonomy and the sequences were submitted to NCBI Genbank and BOLD. The study also elucidated the interactions mediated by plant traits and info-chemicals in brinjal-mealybugnatural enemy tritrophic systems. The study recorded Pusa Purple Long as resistant cultivar and Udit and Haritha as highly susceptible cultivar to C. insolita. The plant traits viz., trichome density, length width ratio of leaf, number of branches, total phenol content and total chlorophyll content exhibited significant correlation with mean population of mealybugs whereas plant height exhibited significant correlation with mean population of natural enemies. The study on info-chemical mediated tritrophic interactions revealed that the concentration and composition of volatile compounds determine the differential selectivity of natural enemies. The volatile compounds identified in this study can also be used as a cue in moderating the behavior of natural enemies in the ecosystems. So a thorough knowledge on the tritrophic relations in the ecosystem will aid in manipulating these interactions to devise a better pest management strategy.ThesisItem Open Access Field tolerance of chilli varieties against sucking pest complex(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2022) Haritha, N K; KAU; Vijayasree, VThe study on the “Field tolerance of chilli varieties against sucking pest complex”was conducted at Department of Agricultural Entomology, College of Agriculture, Vellayani during 2019-2021 with the objective to evaluate chilli genotypes for field tolerance to sucking pest complex viz; Aphis gossypii Glover, Polyphagotarsonemus latus Banks and Scirtothrips dorsalis Hood. A total of 30 genotypes were screened for the field tolerance to the sucking pests, including indigenous genotypes of Kerala, KAU released varieties and accessions from NBPGR. The mean population count of A. gossypii, P. latus and S. dorsalis on 20, 35, 50 and 65 days after transplanting was recorded and significantly lower mean number of A. gossypii was recorded in L3 (2.83 leaf-1), L9 (4.61 leaf-1) and L14 (5.75 leaf-1). The population of P. latus was observed least in the genotype L5 with a mean number of 1.47 mites leaf-1 which was followed by L14 (2.36 leaf-1) and L3 (2.49 leaf-1). The minimum incidence of S. dorsalis was recorded in the genotype L5 which showed a mean population of 2.25 thrips leaf-1 and it was followed by L14 (3.94 leaf-1) and L3 (4.03 leaf-1). The genotype L11 was found most susceptible with the highest number of A. gossypii (23.72 leaf-1), P. latus (6.30 leaf-1) and S. dorsalis (6.75 leaf-1). The damage assessment was done by observing the leaf damage caused by mites and thrips. When the mean leaf damage was recorded on 20, 35, 50 and 65 days after transplanting, P. latus showed least preference to the genotype L5 with a per cent leaf damage of 14.92 and this was followed by L14 (16.92) and L3 (20.92). The minimum damage by S. dorsalis was observed in the genotype L5 with a leaf damage of 15.08 per cent and was followed by L3 and L14 with a leaf damage of 18.33 and 21.08 per cent respectively. The genotype L11 was severely damaged by P. latus and S. dorsalis with a per cent leaf damage of 76.33 and 74.08 respectively. The Per cent Leaf Curl Index (PLI) was calculated based on the leaf damage, for grouping the chilli genotypes into resistant, moderately resistant, susceptible and highly susceptible categories. Based on the mean PLI due to damage by P. latus the genotypes, L5 and L14 were grouped under moderately resistant category. The genotypes L5 and L3 were grouped as moderately resistant based on mean PLI due to damage by S. dorsalis. The genotypes L11, L4, CF1 and IC284628 were coming under the highly susceptible category due to infestation of P. latus and S. dorsalis. Principal Component Analysis (PCA) was carried out based on the mean population of A. gossypii, P. latus and S. dorsalis to find out the tolerant and susceptible genotypes against the sucking pest complex. The genotypes L5, L3 and L14 were found as the tolerant and L11 as the susceptible genotype for which the analysis of morphological traits, biochemicals and nutrients were carried out. Different morphological traits like plant height, total number of leaves plant-1 and leaf area were highest in L3. The number of branches plant-1 and trichome density was highest in L5 and the length-width ratio of leaves in the genotype L14. However, all these morphological characters were found lowest in the genotype L11. Analysis of biochemicals revealed that the total phenol content and capsaicin content was highest in the genotype L5 (0.290 mg g-1 and 0.016mg g-1 respectively) and lowest in the genotype L11. Total protein and total sugar were highest in L11 (6.169 mg g-1 and 0.216 mg g-1 respectively) and lowest in L14. Total nitrogen and total phosphorus were highest in L11 (0.18% and 0.63% respectively) and lowest in L3. Total potassium was highest in L14 (1.08%) and lowest in L11 (0.46%). Correlation studies were done to find out the relationship between the different traits in chilli genotypes and infestation of A. gossypii, P. latus and S. dorsalis. Among the morphological characters, plant height and leaf area had a significant negative correlation with the population of A. gossypii while number of branches plant-1 had a significant negative correlation with the incidence of all the three sucking pests. The total protein and total sugar had a significant positive correlation with the population of A. gossypii, whereas total phenol had a significant negative correlation with the incidence of P. latus and S. dorsalis. Total nitrogen had a significant positive correlation with the population of A. gossypii whereas total phosphorus had a significant positive correlation with the population of S. dorsalis. Based on the mean population of A. gossypii, P. latus and S. dorsalis and the leaf damage caused by them, the genotypes L5, L3 and L14 were observed as the tolerant whereas the L11 was found as the susceptible genotype to these sucking pest complex.ThesisItem Open Access Quantification and characterization of Indian honey bee (Apis cerana indica Fab.) Venom(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2022) Alen, Joy; KAU; Amritha, V SThe research work entitled “Quantification and characterization of Indian honey bee (Apiscerana indica Fab.) venom” was carried out at College of Agriculture, Vellayani during the year 2019 to 2021. The objective of the study was quantification and characterization of Indian honey bee venom during different seasons. Hives of uniform bee strength maintained in the apiary of AICRP on Honey Bees & Pollinators were selected to identify the peak hour of the day at which maximum bee venom can be collected from a hive using a bee venom collector. Venom was collected from hives at different hours starting from 6 am to 6 pm for three days. The optimum duration at which maximum venom can be collected from the hive with minimum damage to the bees were also assessed. Venom was collected for three different durations viz., 30 minutes, 40 minutes and 60 minutes and the quantity of venom collected and mortality was recorded. Seasonal variation was assessed by collecting venom at the peak hour and optimum duration on all the three seasons viz, brood rearing (September - December), honey flow (January - April) and dearth (May-August). The brood parameters and foraging activity of the hives were also assessed at weekly intervals for a period of one month in order to determine whether the bee venom collection has any impact on these parameters. The venom collected during the three seasons were subjected to characterisation and the proportion of components present in the venom were analysed. Control hives were maintained and the data were subjected to ANOVA and paired t test analysis. Observations on the venom collection at hourly intervals of a day revealed that maximum quantity of venom was collected at 2 pm to 3 pm (52.00 mg per hive) and least venom was collected at 7 am to 8 am. Statistical analysis of the data on optimum duration for venom collection showed that highest quantity of venom was collected at 60 minutes duration (55.34 mg per hive), but the mean mortality was high (5.20 bees per hive). Venom collected at 40 minutes and 30 minutes were 34.14 mg and 25.12 mg per hive which were on par. The optimum duration for placing the bee venom collector was selected as 30 minutes considering the low mortality of bees (0.80 per hive) as compared to 40 minutes (2.00 per hive). Significant variation was not observed in the brood parameters as well as in the foraging activity of the venom collected and control hives. Studies on the seasonal variation in bee venom collected revealed that maximum quantity of venom was collected at honey flow season (55.16 mg per high) followed by dearth season (41.00 mg) and brood rearing season (25.12 mg). Maximum mortality was also recorded at honey flow season followed by dearth season and brood rearing season. Brood parameters as well as the foraging activity of the bees did not vary significantly among the seasons. The quantity of bee venom collected had a non-significant positive correlation with temperature and negative correlation with humidity. The characterisation of bee venom samples collected during the three seasons were carried out at SAIF, IIT Bombay by HR LC-MS (High Resolution Liquid Chromatography-Mass Spectrometry) with database (Plant extract Impurity Profiling and Metabolite Identification). Melittin and apamin were identified as the major components, with melittin showing maximum abundance on all the three seasons. No significant difference was recorded in the abundance of both melittin and apamin among the three seasons. Thus, in the present study, highest quantity of bee venom was collected at 2 pm to 3 pm (52.00 mg per hive) and the optimum duration for collection was 30 minutes, considering the bee mortality factors. Studies on the seasonal variation revealed that significantly high bee venom was collected during the honey flow season (55.16 mg per hive), while no significant variation was observed in the brood parameters among the seasons. Characterisation of the bee venom revealed that melittin and apamin were the major components, of which melittin was 8.5 times abundant than that of apamin with no significant variation among the seasons.ThesisItem Embargo Bacillus spp. for seed biopriming to enhance growth in transplants of Solanaceous vegetable crops.(Department of Agricultural Microbiology, College of Agriculture , Vellayani, 2022) Safa, Biju; KAU; Anith, K NThe experimental work entitled “Bacillus spp. for seed biopriming to enhance growth in transplants of solanaceous vegetable crops” was done at Department of Agricultural Microbiology, College of Agriculture, Vellayani, Thiruvananthapuram during academic year 2019-21. Objective of study was to assess the effectiveness of biopriming with spore forming bacilli for plant growth promotion in transplants of solanaceous vegetable crops such as tomato, brinjal and chilli. In vitro as well as in vivo experiments were conducted in this study. In vitro studies included characterization of the bioagents viz, B. pumilus VLY17, B. amyloliquefaciens VLY24 and B. velezensis PCSE10 for plant growth promoting parameters. IAA production was assessed in presence and absence of tryptophan and it was found that B. pumilus VLY17 produced maximum IAA (23.344μgmL1 ) in presence of tryptophan whereas in the absence of tryptophan, B. amyloliquefaciens VLY24 produced maximum IAA (15.072 μgmL-1 ). Ammonia production was observed in B. amyloliquefaciens VLY24 and B. velezensis PCSE10. Direct and indirect antagonism against Pythium sp. was done by dual culture plate assay and agar well diffusion assay respectively. All three bioagents showed inhibitory effects. In agar well diffusion assay, unmeasurable inhibitory zone was observed in case of B. velezensis PCSE10. Roll towel technique was performed to assess seedling vigour of tomato, brinjal and chilli seeds bioprimed with bacterial bioagents and their consortium against hydroprimed and untreated control. In tomato, maximum seedling vigour was observed in seeds treated with B. pumilus VLY17 (556.75). In brinjal, B. amyloliquefaciens VLY24 treated seeds showed maximum vigour (860.5) followed by consortium treatment (828). In chilli, consortial treatment (970) followed by B. pumilus VLY17 (951.25) treatment showed maximum vigour index. In vivo studies were done by raising treated seeds of tomato, brinjal and chilli in protrays. In tomato, three of the treatments showed superior results in growth promotion viz, consortium treatment followed by B. pumilus VLY17 and B. amyloliquefaciens VLY24. In brinjal, B. velezensis PCSE10 showed best results in majority of plant growth promoting traits. In chilli, B. pumilus VLY17 and B. amyloliquefaciens VLY24 showed superior results. Root colonization studies were also done and all the three bioagents were found to be effective root colonizers in all the three crops studied. Results of this study lead to the conclusion that the three endospore formers are highly effective as biopriming agents for enhancing plant growth promotion and development in solanaceous vegetable crops under nursery conditions.ThesisItem Open Access Documentation and management of pests of jasmine, Jasminum spp.(Department of Agricultural Entomology, College of Agriculture ,Vellayani, 2022) Swathy, I M; KAU; Malini, NilamudeenIn Kerala, jasmine is mostly grown as an ornamental crop in homesteads. Recently, there is an increase in jasmine cultivation due to its high export potential. In this scenario, knowledge about the pests and defenders of jasmine and their eco-friendly management under Kerala condition is highly essential. With this backdrop, the study entitled “Documentation and management of pests of jasmine, Jasminum spp.” was carried out at Department of Agricultural Entomology, College of Agriculture, Vellayani during the period of 2019 to 2021. The objectives of the study were to document the pests infesting Jasminum spp., their damage and symptoms, natural enemies associated with the pest and to develop suitable pest management measures. The documentation conducted at three districts viz., Thiruvananthapuram, Kollam and Alappuzha recorded sixteen pests. Jasmine budworm (Hendecasis duplifascialis Hampson), jasmine leaf webworm (Nausinoe geometralis (Guenee), Nausinoe perspectata (Fabricius)), shoot webworm (Margaronia unionalis Hubner), jasmine gallery worm (Elasmopalpus jasminophagus (Hampson)), blossom midge (Contarina maculipennis Felt), lacewing bug (Corythauma ayyari Drake), flower thrips (Thrips orientalis (Bagnall)), flea beetle (Hyphasis sita (Maulik)), grasshoppers (Diabolocatantops pinguis (Stal), Neorthacris acuticeps (Bolivar)), tortoise beetle (Cassida sp.), leafhopper (Kolla ceylonica (Melichar)), jasmine bug (Antestiopsis cruciata (Fabricus), moth bug (Ricania sp.), whitefly (Dialeurodes sp.), mealy bug (unidentified) and red spider mite (Tetranychus sp.). The grasshoppers (D. pinguis, N. acuticeps) tortoise beetle (Cassida sp.) and leafhopper (K. ceylonica) were reported for the first time from Kerala as pest of jasmine. Natural enemies associated with pests of jasmine were also documented in which the spiders were prominent predators followed by praying mantis. The spiders documented were white lynx spider (Oxyopes shweta Tikader), crab spider (Camaricus sp.), pantropical jumping spider (Plexippus paykulli (Audouin)), heavy bodied jumper (Hyllus semicupreus (Simon)), two striped jumper (Telamonia dimidiata (Simon)), flower crab spider (Thomisus lobosus Tikader), grass cross spider (Argiope catenulata (Doleschall)), long jawed orb-weaver (Tetragnatha maxillosa Thorell) and banded phintella (Phintella vittata (C. L Koch)). Apart from spiders, Asian mantis (Hierodula membranacea Burmeister) and praying mantis (Odontomantis pulchra Olivier) were also documented. Spiders Camaricus sp., A. catenulate and T. maxillosa were reported for the first time from Kerala on jasmine. A consolidated documentation of spider and mantid predators from jasmine ecosystem is first of its kind from Kerala. Pupal parasitoid Brachymeria nephantidis Gahan and larval parasitoid Apanteles sp. were found parasitizing on the jasmine leaf webworm, N. geometralis and larval parasitoid Phanerotoma hendecasiella (Cameron) was found parasitizing on jasmine budworm H. duplifascialis and jasmine gallery worm E. jasminophagus. Studies on the biology of H. duplifascialis and N. geometralis were carried out under laboratory condition. H. duplifascialis had an average of 3.35 + 0.11, 11.15 + 0.08 and 5.25 + 0.10 days of egg, larval and pupal period respectively whereas N. geometralis recorded an egg, larval and pupal period of 3.35 + 0.11, 10.65 + 0.20 and 6.65 + 0.11 days respectively. The prophylactic and curative field experiments were conducted at College of Agriculture, Vellayani for evolving efficient pest management practices. It was found that the prophylactic treatments with biopesticides, oil based formulation of Metarhizium anisopliae NBAIR Ma 4 @ 10 mL L-1 and Beauveria bassiana NBAIR Bb 5 @ 10 mL L-1 caused cent per cent reduction in the population of C. ayyari at 60 days after planting. The population of H. duplifacsialis was also nil in these plots. A three and two fold increase in flower yield was recorded for M.anisopliae and B.bassiana, respectively in comparison to untreated plots. The treatments were found safe to spider predators also. Among the curative treatments, chlorantraniliprole 8.8% w/w+Thiamethoxam 17.5 % w/w SC @150g a.i ha-1 was the best with no pest incidence and also had three-fold increase in mean flower yield (8.10 g plant -1 ) compared to the untreated plots. However, it was not safe to spiders. Among the biopesticides, oil based formulation of M. anisopliae NBAIR Ma 4 @ 10 mL L-1 and B. bassiana NBAIR Bb 5 @ 10 mL L-1 caused 73 and 67 per cent reduction in the population of H. duplifascialis and 90 and 89 per cent respectively for C.ayyari. The mean flower yield in M. anisopliae NBAIR Ma 4 @ 10 mL L-1 and B. bassiana NBAIR Bb 5 @ 10 mL L-1 treated plots was 2.7 and 2.2 times higher than that in untreated plots. Both treatments were found safe to spiders. From the present study, it can be concluded that, of the sixteen pests infesting jasmine, H. duplifascialis, C. ayyari and C. maculipennis attained the status of major pests. However, considering the presence of different pests belonging to various orders on jasmine, pest surveillance is highly recommended in the scenario of area expansion. The study recorded an extensive spectrum of spiders and parasitoids which played a key role in preventing the population build-up of pests. Prophylactic sprayings of oil based formulation of M. anisopliae NBAIR Ma 4 @ 10 mL L-1 or B. bassiana NBAIR Bb 5 @ 10 mL L-1 can be recommended during the initial appearance of pests on jasmine and the same can be recommended for curative management. However, for managing severe incidence of pest, single spray of Chlorantraniliprole 8.8% w/w+ Thiamethoxam 17.5 % w/w SC @150 g a.i ha-1 can be recommended.ThesisItem Open Access Bioactivity of essential oils against insect pests of brinjal(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2022) Manoj, K; KAU; Thania Sara, VargheseThe study entitled “Bioactivity of essential oils against insect pests of brinjal” was undertaken in the Department of Agricultural Entomology at College of Agriculture, Vellayani during the period 2019-2021 with an objective of evaluating the bioactivity of essential oils viz., basil oil, citronella oil, eucalyptus oil and orange oil against insect pests of brinjal and characterization of the most effective essential oils. Laboratory screening of essential oils viz., basil oil, eucalyptus oil, citronella oil and orange oil was conducted against one sucking pest (mealy bug, Coccidohystrix insolita (Green)) and one chewing pest (Hadda beetle, Henosepilachna vigintioctopunctata (Fabricius)) in brinjal. Acute toxicity of the essential oils against the test insects was determined by leaf dip bioassay. Preliminary test dose range causing 10 to 100 per cent mortality was fixed and based on these 6 doses including a control treatment was taken. Based on the results of leaf dip bioassay of essential oils against mealy bug, LC50 and LC90 of basil oil, eucalyptus oil, citronella oil and orange oil were (0.49 and 1.33), (1.86 and 4.28), (0.64 and 2.39) and (1.54 and 3.53) per cent respectively at 24 hours after treatment (HAT). The corresponding LC50 and LC90 values of the above four oils at 48 HAT were (0.29 and 0.89), (0.72 and 1.92), (0.28 and 1.22) and (1.06 and 2.17) per cent respectively. Against hadda beetle the LC50 and LC90 values of basil oil, eucalyptus oil, citronella oil and orange oil were (1.25 and 2.85), (3.35 and 5.09), (0.93 and 1.52) and (3.48 and 9.11) per cent respectively at 24 HAT. While the corresponding LC50 and LC90 values at 48 HAT were (0.85 and 1.70), (2.09 and 3.51), (0.63 and 1.14) and (2.02 and 4.05) per cent respectively. Based on toxicity bioassays, basil and citronella oil had lower LC50 and LC90 values than eucalyptus and orange oil against both mealy bug and hadda beetle at both 24 and 48 HAT and these two were selected for further lab and field evaluation. Repellent and antifeedant effect of the selected essential oils from the first experiments viz., basil oil, citronella oil were evaluated against hadda beetle by modified preference method and no choice method respectively. At 0.5 to 1 per cent 76 concentration, both basil and citronella oil showed 90-100 per cent repellence at 30 and 60 minutes of treatment. On other hand, 0.5 to 1 per cent concentration of basil and citronella oil showed antifeedant effect of 100 per cent after 24 hours of treatment. Before conducting field evaluation of essential oils, bloom test and phytotoxicity evaluation on brinjal plants were done. Bloom test was conducted to check the emulsification of essential oil and surfactant formulation in distilled water. Results were showing “Good” bloom rating for basil oil and “Excellent” bloom rating for citronella oil. Phytotoxicity evaluation of basil and citronella oil was carried on brinjal plant as per the protocols of CIBRC (Central Insecticide Board and Registration Committee). Basil oil and citronella oil at 0 to 0.7% were not showing any phytotoxic symptoms on brinjal plants while the higher doses of 1%, 1.5% and 2% were showing slight moderate and severe phytotoxic symptoms. Based on the laboratory and phytotoxicity evaluation, two doses of basil oil and citronella oil (0.5% and 0.7%) were selected for the pot culture experiment along with two chemical checks and an untreated control. The experiments were laid in completely Randomized design with three replications. In field study, spraying of basil oil and citronella oil at 0.7% showed significant reduction in aphid population and it was statistically on par with thiamethoxam 25% WG even at 14 DAT. The leaf webber population was also significantly reduced for basil and citronella oil at 0.7% and it was statistically on par with chlorantraniliprole 18.5% SC even at 14 DAT. Basil oil and citronella oil at 0.7% showed significant reduction in the shoot and fruit borer damage after 14 days of treatment and it was statistically on par with chlorantraniliprole 18.5% WG at 14 days after treatment. Basil oil and citronella oil at 0.7 per cent showed significant reduction in the lady bird beetle population. There was no statistical difference among the different treatments with regard to the biometric observations viz., total number of leaves, damaged leaves, plant 77 height after the field spraying, however the fruit yield was recorded significantly higher in chlorantraniliprole 18.5% WG. GC-FID/GC-MS studies on basil and citronella oil revealed that the predominant component of basil oil is Methyl chavicol (75.73%), followed by Linalool (18.21%) and (8) Cuprenene (1.58%). In citronella oil, Geranial (64.77%) was the most abundant component followed by Citronellyl acetate (7.92%), Geraniol (7.08%), (Z) Iso citral (5.29%) and Neral (3.60%).ThesisItem Open Access Development of formulations from Samadera indica Gaetrn. for the management of leaf feeding pests in snake gourd(Trichosanthes anguina L.)(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2022) Remya, S; KAU; Nisha, M SThe study entitled ‘Development of formulations from Samadera indica Gaetrn. for the management of leaf feeding pests in snake gourd (Trichosanthes anguina L.)’ was carried out in the Department of Agricultural Entomology, College of Agriculture, Vellayani and at Council of Scientific and Industrial Research – National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), Thiruvananthapuram during 2018 to 2021. Objectives of the study were exploration of anti-insect properties of bark and seeds of S. indica, identification of bioactive compounds in the effective extract, development of suitable formulations and field evaluation of the same against pumpkin caterpillar, Diaphania indica Saund and epilachna beetle, Henosepilachna septima (Dieke). Estimation of lethal doses viz., LD50 and LD90 of bark and seed extracts by probit dose analysis showed that LD50 of bark extract in hexane, acetone, ethanol extract and aqueous extract were 1.66, 1.03, 1.51 and 2.38% respectively against D. indica and 2.17, 1.95, 1.68 and 2.49% respectively against H. septima. Meanwhile, LD90 values were 6.49, 7.05, 5.24 and 7.90% respectively against D. indica and 6.82, 6.60, 6.17 and 7.85% against H. septima. In the case of seed extract, LD50 values were 1.79, 0.59, 1.03 and 1.54% respectively against D. indica and 1.63, 0.83, 1.60 and 2.43% against H. septima. LD90 values were 6.99, 5.17, 7.05 and 9.17% against D. indica and 9.53, 5.27, 7.94 and 9.02% against H. septima. Results of in vitro studies on antifeedant effect of S. indica bark extracts against D. indica showed that ethanol extract @ 5.24% exhibited the highest leaf protection of 62.79 per cent at 72 Hours After Treatment (HAT). In the case of H. septima, ethanol extract @ 6.17% resulted in 65.00 per cent leaf protection. Regarding insecticidal effect, ethanol extract @ 5.24% resulted in 93.33 per cent mortality of second instar larvae of D. indica. Meanwhile, in grubs of H. septima, ethanol extract @ 6.17% inflicted 91.67 per cent mortality. Insecticidal effect of both the extracts was found to be statistically on par with chemical check (Malathion 50 EC 0.1%). With regard to insect biology, there was increase in larval duration (15.00 days), pupal duration (5.33 days), reduction in pupal weight (0.19 g) and reduction in adult longevity (4.33 days) in D. indica, whereas in control, larval and pupal period were 9.67 and 2.67 days each, pupal weight was 0.31 g and longevity of adults was 7.67 days. Similar trend was observed in H. septima. Among various extracts from S. indica seeds, acetone extract @ 5.17% resulted in the highest leaf protection of 74.41 per cent in D. indica and acetone extract @ 5.27% exhibited 71.79 per cent leaf protection in H. septima. With respect to insecticidal effect, acetone extract @ 5.17 and 5.27% each caused 86.67 per cent mortality in D. indica and H. septima respectively. Considering biology of the insects, there was prolongation in larval period to 17.00 days, pupal period to 8.67 days, reduction in pupal weight to 0.25 g and reduction in adult longevity to 6.33 days in D. indica as against larval period of 12.67 days, pupal period of 5.33 days, pupal weight of 0.35 g and adult longevity of 7.67 days in control. Similar was the trend with H. septima also. A comparison between LD50 and LD90 of bark and seed extracts pointed out that seed extract contained more potent compounds with insecticidal properties. Hence, seed extract was taken for further studies. Chromatographic fractions from acetone extract of seeds @ 5% exhibited mean leaf protection of 91.83 per cent in D. indica and 85.71 per cent in H. septima. Meanwhile, there was mortality of 73.33 per cent in both the pests. Analysis of chromatographic fractions revealed the presence of quassinoids viz., samaderin A, samaderin B, samaderin C and cedronin in the seed extract. Molecular structures were elucidated to confirm the identity of the compounds. Two formulations of S. indica seed extract were prepared by mixing seed extract, emulsifier and distilled water in different proportions. Formulation A contained acetone extract of S. indica seed, tween 80 and distilled water in 15: 5: 80 ratio. Formulation B was prepared by mixing seed extract of S. indica in acetone, tween 80 and span 80 (1: 1) and distilled water in 15: 5: 80 ratio. Both the formulations A and B were equally effective against D. indica and H. septima under in vitro conditions, with 80.00 per cent mortality each at 72 HAT. Safety evaluation on beneficial insects indicated that formulation A @ 1% resulted in 30.00 per cent mortality in honey bee after 24 HAT, while in A. taragamae, it was 23.33 per cent. Furthermore, both the formulations were stable under normal room temperature for six months. Formulation A @ 1% recorded 71.67 to 80.00 per cent mortality in D. indica and H. septima from the day of preparation till sixth month of storage. Meanwhile, formulation B @ 1% resulted mean percentage mortality of 70.00 and 75.00 per cent in D. indica and H. septima. Considering the insecticidal effect under in vitro conditions and environmental feasibility, formulation A was chosen for in vivo studies. Field experiment was carried out to test the efficacy of the botanical in comparison with biopesticide and chemical at Instructional Farm, Vellayani in snake gourd (variety Kaumudi). Formulation A @ 2% was evaluated for its efficacy against D. indica and H. septima at vegetative stage and 50 per cent flowering stage. Observations were taken on pest population and percentage of damaged leaves. It can be deduced that formulation A @ 2% was as effective as neemazal @ 0.2% as evident with reduction in pest population at vegetative and 50 per cent flowering stage of the crop. With regard to reduction in leaf damage, formulation A @ 2% excelled equally as neemazal @ 0.2% at vegetative stage. The study revealed that both bark and seed extracts of S. indica exhibited feeding deterrence, insecticidal properties and caused adverse effects in the biology of D. indica and H. septima. Anti-insect properties are more prevalent in the seeds and they contained the bioactive compounds samaderins A, B, C and cedronin. Formulations containing acetone extract of S. indica seeds, tween 80 and distilled water (15: 5: 80) @ 1 and 2% each were effective against both the pests under in vitro and in vivo conditions respectively and were stable for a period of six months under room temperature. Hence, it can be concluded that formulations from S. indica can be considered as safer botanical insecticides in this era of organic farming.ThesisItem Open Access Field efficacy of biocapsules of entomopathogenic fungi for the management of vegetable pests(Department of Agricultural Entomology, College of Agriculture,Vellayani, 2022) Parvathy, Maloth; KAU; Reji Rani, O PThe study entitled “Field efficacy of biocapsules of entomopathogenic fungi for the management of vegetable pests” was conducted at the Biocontrol Laboratory for Crop Pest Management, Department of Agricultural Entomology, College of Agriculture, Vellayani, Thiruvananthapuram, during the year 2018-2021. The objective of the study was to evaluate the efficacy of biocapsules of Beauveria bassiana (Balsamo) Vuillemin, Metarhizium anisopliae (Metschnikoff) Sorokin, Lecanicillium lecanii (Zimmermann) Zare and Gams and Lecanicillium saksenae (Kushwaha) Kurihara and Sukarno for the management of major groups of vegetable pests. The study also intended to standardize the dose of biocapsules in managing amaranthus leaf webber Spoladea (Hymenia) recurvalis F., okra shoot and fruit borer Earias vittella F. and cowpea aphid Aphis craccivora Koch. The biocapsules of fungi were formulated at a higher spore load of 1010 with HPMC coating and chitosan as carrier, following the protocol developed by Remya and Reji (2019). In the first field experiment to evaluate the efficacy of biocapsules in managing defoliators in amaranthus, it was revealed that, Metarhizium and Beauveria capsules @ 3 L-1 sprayed twice (at weekly intervals) was effective causing 83.69 and 69.97 per cent reduction in population of S. recurvalis respectively. Lower doses of 2 and 1 capsules L -1 were less effective causing, 47.39 to 66.5 per cent reduction in larval population. Spraying spore suspensions of these fungi @ 108 mL-1 resulted in 91.27 to 100 per cent reduction, while in flubendiamide 39.35 SC, it was 89.84 per cent. Treatment with Metarhizium and Beauveria capsules did not affect the natural enemy population significantly, the mean population being 2.33 to 3.67 plant-1 . The corresponding population was 1.44 in flubendiamide 39.5 SC and 3.67 in untreated control. The yield recorded in the plots treated with Metarhizium and Beauveria capsules @ 3 L -1 was high (2.67 and 2.30 kg plot-1 ) when compared to that in untreated plot 0.80 kg plot-1 . Results of the second experiment to evaluate the efficacy of biocapsules in managing fruit and shoot borer E. vittella in okra concluded that, Beauveria capsule @ 3 L -1 and Metarhizium capsule @ 3 L-1 were equally effective when sprayed at weekly intervals leading to 84.96 and 79.64 per cent reduction in the shoot damage respectively. The percentage reduction in shoot damage was only 65.32 to 73.86 per cent reduction in lower doses of capsules. In plots treated with spore suspensions, the mean shoot damage recorded was 90 to 95 per cent. Percentage reduction in chlorantraniliprole 18.5 SC was 90.71. Considering the fruit damage, Metarhizium capsule @ 3 L-1 was found to be the best treatment causing 100 per cent reduction in damage caused by E. vittella, while it was 89.75 per cent with Beauveria capsule@ 3 L -1 . Reduction in fruit damage ranged from 67.82 to 82.81 per cent in the lower doses of capsules. Highest reduction in the fruit damage observed with spore suspensions of Beauveria and Metarhizium @ 108 mL-1 (93.16 and 100 per cent, respectively). Similar results were obtained in the case of okra leaf roller, Metarhizium @ 2 L-1 and Beauveria capsule @ 3 L -1 were found to be the best treatment causing 96.38 and 85.80 per cent reduction in population of Sylepta derogata F., while it was 80.23 per cent with Metarhizium capsule @ 3 L-1 . Reduction in population ranged from 41.35 - 68.72 per cent in the lower doses of capsules. Highest reduction in the population of S. derogata observed with spore suspensions of Beauveria and Metarhizium @ 108 mL-1 (100 per cent). Percentage reduction in chlorantraniliprole 18.5 % SC was 93.41. Treatment with biocapsules capsules did not cause any adverse affect on natural enemy population, in okra field. The yield obtained from different treatments did not vary significantly. Third experiment in cowpea field revealed that, foliar application of L. saksenae capsule @ 3 L -1 and L. lecanii capsule @ 3 L-1 were equally effective to A. craccivora when sprayed twice (at weekly intervals) causing 94.38 and 92.28 per cent reduction in the population respectively. Reduction in population noted was 57.54 to 63.96 per cent with lower dose @ 2 capsules L-1 while it was least with single capsule treatment (37.51 to 44.73 per cent). The spore suspensions were more effective resulted than the lower doses (78.73 - 83.53 per cent reduction). The chemical check thiamethoxam 25 WG recorded 95.79 per cent reduction in population. Biocapsule treatment did not affect natural enemy population significantly. The yield recorded in the plots with L. saksenae capsules @ 2 and 3 L-1 was high (1.85 and 1.56 kg plot-1 ) when compared to other treated plots and untreated plot (1- 1.45 kg plot-1 ). Therefore, it is concluded that biocapsules of Metarhizium and Beauveria, can effectively manage defoliators in amaranthus and borers in okra and those of L. lecanii and L. saksenae can be recommended for pea aphids, without affecting the natural enemies and yield significantly.
