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ThesisItem Open Access Morphological variations of root knot nematode in vegetables and banana(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2017) Chinchu, P Babu; KAU; Narayana, RThe study entitled “Morphological variations of root knot nematode in vegetables and banana” was conducted at College of Agriculture, Vellayani during 2015-17 with the objective to study the morphological and morphometric variations of root-knot nematode in brinjal, okra, tomato and banana in Kerala. Morphological and morphometrical studies of females, perineal pattern, second stage juveniles and males of root knot nematodes collected from Dhanuvachapuram, Kattakada and Vellayani of Thiruvananthapuram district; Balagram, Pampadumpara and Thovalappady of Idukki district; Chazhoor, Thalikulam and Thaniyam of Thrissur district infecting brinjal, okra, tomato and banana were done and the data was analysed to identify the species. M.incognita (Kofoid & White, 1919) Chitwood, 1949, M. javanica (Treub, 1885) Chitwood, 1949, M. arenaria (Neal, 1889) Chitwood, 1949 and M. chitwoodi Golden, O'Bannon, Santo & Finley 1980 were identified from brinjal, okra, tomato and banana in Thiruvananthapuram, Idukki and Thrissur districts of Kerala. The study indicated M. incognita as the major species of root knot nematode in Thiruvananthapuram district (91.66%) with highest percentage of occurrence in brinjal and tomato (27.77). In Idukki district, the major species of root knot nematode was M. javanica (66.66%) with highest percentage of occurrence from brinjal and banana (33.33). In Thrissur district, M. arenaria was found to be the major species (66.66%) with highest percentage of occurrence in okra (37.5). M. incognita was found to be the major species in brinjal (55.55%), okra (44.44%), tomato (55.55%) and banana (44.44%) in Thiruvananthapuram, Idukki and Thrissur districts. The extent of parthenogenesis of root knot nematode was found to be very high (97.22%) in these populations. Intraspecific morphological variations were observed within M. incognita, M. javanica and M. arenaria with respect to shape of females, length and position of neck, perineal pattern morphology, tail characters including rectum dilation. Interpopulation comparison of mature females, perineal pattern and second stage juveniles of M. incognita showed that the characters length, width, neck length, stylet length, LMB, WMB and ratio a of females, LVS, AVS, ATT and IPD of perineal pattern and body length, stylet length, H-MB, ABW, tail length, ratio c and c’ were recorded as stable characters. Interpopulation comparison of mature females, perineal pattern and second stage juveniles of M. javanica showed that all the characters of females, perineal pattern and second stage juveniles were stable characters and in M. arenaria, the characters like body length, width, neck length, stylet length, LMB and WMB of females, LVS, AVS, ATT and IPD of perineal pattern and length, stylet length, H-MB, ABW and tail length were recorded as stable characters and found useful in characterizing species. Intraspecific morphological and morphometric variations of M. incognita, M. javanica, M. arenaria were recorded from four host plants in three districts in Kerala. M. arenaria and M. javanica showed high variability between the populations compared to M. incognita in Kerala. The study indicated that M. incognita, M. javanica and M. arenaria were the major species infesting vegetables and banana in Kerala. Among the sampled populations, M. hapla was not identified which shows that M. hapla is not common in Kerala conditions. The study recorded the first report of species having morphological and morphometrical characters similar to M. chitwoodi from okra in Thiruvananthapuram which opens way to molecular studies in future.ThesisItem Open Access Pathogenicity of indigenous entomopathogenic fungi against select lepidopteran pests(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2016) Praveena, A; KAU; Sudharma, KThe present study entitled “Pathogenicity of indigenous entomopathogenic fungi against select lepidopteran pests” was carried out in the Department of Agricultural Entomology, College of Agriculture, Vellayani during 2014-2016 with the objective to identify indigenous entomopathogenic fungi and evaluate their pathogenicity to lepidopteran pests of banana and vegetables. Survey was conducted in five agroecological zones of Thiruvananthapuram district at bimonthly intervals during 2015-16, for the isolation of fungi. Fungi from mycosed cadavers and 900 soil samples, collected from cultivated and uncultivated fields were isolated. Of the ten isolates of fungi selected from the 115 fungal isolates obtained, three were from mycosed cadavers which consisted of two isolates of Beauveria bassiana (Balsamo) Vuillemin (SP2 and SP4) and one isolate of Fusarium oxysporum Schlecht (SP1). Of the seven isolates from soil, one isolate was Fusarium solani (Mart.) Sacc. (SP6), five were isolates of Metarhizium anisopliae Metschnikoff (Sorokin) and one isolate was Purpureocillium lilacinum Thorn (Samson). Four isolates of M. anisopliae were trapped using larvae of Galleria melonella L. and one was trapped using grubs of Odoiporous longicollis Olivier. The isolate, S10 was obtained through soil plate method, with selective media. Symptoms of fungal infection varied, which was mainly reflected in the mycelial colour and growth of the isolates. Morphological and cultural characteristics also varied among the fungal isolates. Further, molecular characterization of the fungi was done through ITS sequencing. GenBank accession numbers for all the ten isolates were obtained on submission of nucleotide sequence in National Center for Biotechnology Information (NCBI). Among the various indigenous isolates, highest spore count was recorded in the M. anisopliae isolate, SP11 (28.01 x 107 spores mL-1) at 14 days after inoculation. The pathogenicity of the ten indigenous isolates and two isolates from National Bureau of Agricultural Insect Resources (NBAIR) were evaluated against five lepidopteran insects infesting banana and vegetables at different concentrations. The isolate M. anisopliae (SP8) recorded the highest mortality of 83.33 to 100 per cent and 64.44 to 95.83 per cent against the second instar larvae of Diaphania indica Saunders and first instar larvae of Leucinodes orbonalis Guenee at 107 to 109 spores mL-1 at seven days and five days after treatment respectively. The isolates SP11 and Ma4 of M. anisopliae that caused mortality of 83.33 to 100 per cent and 63.33 to 100 per cent were the most effective isolates against second instar larvae of Sylepta derogata Fabricius and Hymenia recurvalis Fabricius respectively. All the isolates except M. anisopliae (SP11) and B. bassiana (Bb5a) were non pathogenic to the larvae of Spodoptera litura Fabricius. The colour of the mycelial growth varied with isolates. A pot culture experiment was conducted in the Instructional Farm, Vellayani during April to June 2016, for the evaluation of seven indigenous isolates and two NBAIR isolates against leaf webbers in amaranthus, variety Arun. The lowest number of plants infested by webbers, webbings plant-1 and larvae web-1 at 14 days after treatment and the highest yield was recorded in the isolate M. anisopliae (SP11) @ 108 spores mL-1 and it was followed by M. anisopliae Ma4 and SP8 . To conclude, ten indigenous isolates of entomopathogenic fungi were collected from mycosed cadavers and soil and were identified as B. bassiana (SP2, SP4), F. oxysporum (SP1), F. solani (SP6), M. anisopliae (SP7, SP8, SP9, SP11 and SP13) and P. lilacinum (S10) through morphological, cultural characters and molecular characterization. Pathogenicity test to five lepidopteran pests showed that M. anisopliae (SP7, SP8, SP9, SP11, SP13) and NBAIR isolates of B. bassiana (Bb5a) and M. anisopliae (Ma4) were pathogenic to D. indica, H. recurvalis, L. orbonalis and S. derogata. Results of pot culture experiment showed that the indigenous isolates M. anisopliae (SP11) and (SP8) and NBAIR isolate M. anisopliae (Ma4) can be exploited for the management of leaf webbers in amaranthus.ThesisItem Open Access Bioefficacy of Quisqualis indica L. and Samadera indica gaetrn against tobacco caterpillar, spodoptera litura fabricius (LEPIDOPTERA: NOCTUIDAE) in poly house condition(Depatment of Agricultural Entomology, College of Agriculture, Vellayani, 2016) Anusree, S S; KAU; Nisha, M SAn investigation entitled “Bioefficacy of Quisqualis indica L. and Samadera indica Gaetrn. against tobacco caterpillar, Spodoptera litura Fabricius (Lepidoptera: Noctuidae) in polyhouse condition” was conducted at College of Agriculture, Vellayani during 2014-16. The main objectives were to evaluate the effect of aqueous and solvent extracts of Q. indica flower and S. indica leaf on behavioural and physiological changes of S. litura and to test the potential of the selected plant extracts against S. litura infesting cowpea under polyhouse condition. Aqueous and solvent extracts of Q. indica flower and S. indica leaf were tested for antifeedant and insecticidal action against larvae of S. litura under in vitro condition. Antifeedant activity of aqueous extracts of Q. indica flower and S. indica leaf at 5, 10 and 15 % concentrations showed percentage leaf protection ranging from 0 to 10.98. Solvent extracts viz., ethyl acetate and methanol extracts of Q. indica flower and S. indica leaf at 1.25, 2.5 and 5 % concentrations showed percentage leaf protection ranging from 13.23 to 45.62. Maximum antifeedant activity (45.62 %) was exhibited by methanol extract 5 % of S. indica leaf at 24 hours after treatment. The extracts obtained through cold and soxhlet extraction methods were compared for the antifeedant activity against S. litura. Cold extraction was significantly superior to soxhlet extraction giving leaf protection of 12.72 % for Q. indica flower extract and 21.12 % for S. indica leaf extract. Decreasing trend of antifeedant action with increased exposure time was noticed for both the plants. The insecticidal effect of the extracts was assessed through two application methods, spraying and leaf dip method. Spraying method was effective for both the plant extracts, while leaf dip method was effective for S. indica leaf extract only. Cold extract of Q. indica flower 5% with methanol was found to be highly toxic to S. litura larvae with maximum percentage mortality of 93.51 in spraying method. Methanol cold extract 5 % of S. indica leaf exhibited 73.55 % mortality in spraying method and 41.67 % mortality in leaf dip method. Cold extraction method was found to be significantly superior for both Q. indica flower (70.05 %) and S. indica leaf (50.37 %) than soxhlet extraction in spraying method. The insecticidal effect assessed through dry film method showed that cold extracts of Q. indica flower and S. indica leaf exhibited larval mortality of 36.05 % and 13.52 % respectively. An increase in mortality with increased exposure was observed for both plant extracts. Effect on adult emergence of S. litura (deformation and mortality of larvae, pupae and adults, time taken for pupation, pupal duration, pupal weight and adult longevity) showed that the aqueous and solvent extracts of both plants did not have any influence on larvae, pupae and adults. Cold extracts of Q. indica flower and S. indica leaf exhibited significant larval and pupal mortality ranging from 8.33 to 30 % and 11.67 to 31.98 % respectively. Effect on fecundity and egg hatchability revealed that the plant extracts did not possess significant effect on number of eggs laid and number of eggs hatched. To assess the potential of the selected treatments, methanol extract (5 %) of Q. indica flower and S. indica leaf, a pot culture experiment was done under polyhouse condition on cowpea. It was compared with quinalphos 25 EC 0.05 % and biocontrol agent, Beauveria bassiana (Bb 5) 20 g/L. The percentage leaf area damage in 5 % methanol extract of Q. indica flower and S. indica leaf was 48.56 and 63.64 respectively. Maximum larval mortality of 84.07% was observed in quinalphos 0.05 % followed by 5 % methanol extract of Q. indica flower (61.45 %) and S. indica leaf (40.35 %). . From the above study it is concluded that methanol cold extract (5 %) of flowers of Q. indica and leaves of S. indica have insecticidal action against earlier instars of S. litura. These plants can be exploited for formulating potential green pesticides.ThesisItem Open Access Taxonomy of rhynchophorinae (COLEOPTERA: DRYOPHTHORIDAE) of Kerala(Department of Agricultural Entomology, College of Agriculture, Padannakkad, 2016) Arun Kumar, Singh; KAU; Ramesha, BThe taxonomy of weevils under the subfamily Rhynchophorinae (Coleoptera: Dryophthoridae) was carried at the College of Agriculture Padannakkad, Kasargod, Kerala and seven different agro ecological zones of Kerala during 2014-2016. Study was based on survey carried out in agro and forest ecosystems of Kerala and the samples collected from these ecosystems. Commercially available pheromone traps for the collection of red palm weevil, banana pseudostem weevil and banana rhizome weevil were installed in five agroclimatic regions viz., Northern Zone, (RARS, Pilicode); High range (RARS, Ambalavayal); Central Zone (RARS, Pattambi); Problem zone (RARS, Kumarakom) and Southern Zone (RARS, Vellayani). Traps were also installed in the fields of BRS, Kannara and ORARS, Kayamkulam. The other two weevils, i.e. Diocalandra frumenti and Sitophilus oryzae were collected from households and fields of the aforesaid seven regions. The study also includes specimen stored in Malabar Insect Repository (MIR) and the specimens of Rhynchophorus ferrugineus collected from CPCRI regional station, Kayamkulam, Kerala. An annotated checklist of world Rhynchophorinae was prepared and results revealed that the subfamily Rhynchophorinae includes 955 species under 124 genera and 6 tribes. The distribution of these weevils is more concentrated in Oriental and Neotropical regions (70%). Maximum number of species was described during the 1851-1950. Highest contribution from coleopterists was by Heller (89 species) followed by Chevrolat (76 species), Faust (76 species), Guenther (68 species). Taxonomy ultimately narrowed down to focus on the 770 specimens of five species under five genera viz., Cosmopolites sordidus, Diocalandra frumenti, Odoiporus longicollis, Rhynchophorus ferrugineus and Sitophilus oryzae. Collected specimens of individual species were segregated into different populations according to the morphological variations within the species. The present study of economically important five species had 249 illustrations and 149 line diagrams.Detailed description of all the taxonomic characters like head, rostrum, (dorsal and lateral), antennae, pronotum, elytron, femur, tibia, tarsus, venter and genitalia were studied and presented with line diagrams. Taxonomic description of all the five species were supplemented with standard taxonomic terminology along with genital characters and loaded with the morphometric ratios. The taxonomic key was prepared for all the known species under genera Cosmopolites, Diocalandra, Odoiporus and Rhynchophorus. Based on the morphological characters all five species were segregated in different groups. The taxonomic study revealed that, morphological variations present among the groups may be due to environmental conditions, availability of food, and life stage of the plant on which they are feeding on. All the variations within the species were depicted with the differential distinguishing characters along with line diagrams. Among all five species, major difference was observed within the three groups of Odoiporus longicollis which may be a new species. More morphological and molecular level studies are needed for the confirmation of new species if any.ThesisItem Open Access Novel bioformulations of entomopathogenic fungi and their efficacy aganist banana weevils(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2018) Remya, S; KAU; Reji Rani, O PThe study entitled ‘Novel bioformulations of entomopathogenic fungi and their efficacy against banana weevils’ was carried out at Dept. of Agrl. Entomology, College of Agriculture, Vellayani during 2016-2018, with the objective to develop novel formulations of entomopathogenic fungi, Metarhizium anisopliae (Metch.) Sorokin, Beauveria bassiana (Bals.) Vuillemin and to evaluate their efficacy in managing banana weevils. It was intended to develop capsule and gel formulations. Experiment to standardize a coating material for developing capsules revealed that Hard Gelatin Transparent (HGT), Hard Gelatin Coloured (HGC) and Hydroxy Propyl Methyl Cellulose (HPMC), were equally stable under ambient conditions of storage (26 -33°C and RH 60-80%). On testing their ability to disintegrate under field conditions, it was noted that chitosan filled HGT capsules easily disintegrated at 20% soil moisture after 36 h and after 24 h at 30 % soil moisture. It took 144 h for all capsules to disintegrate in sheath or leaf axil and 24 h in bore holes. Talc and chitosan were superior, in maintaining storage stability as well as degradability. A trial conducted to determine the moisture content of capsules, revealed that 10 % was the ideal moisture level content of the ingredient, to maintain storage stability as well as viability of the formulation. Viability noticed after three months was 2.29 × 107 cfu mL-1 and 2.27 × 107 cfu mL-1 in chitosan based capsules of M. anisopliae and B. bassiana and 2.10 × 107 cfu mL-1 and 0.76 × 107 cfu mL-1 in talc based capsules. Therefore, capsules were developed with HGT coating, with chitosan / talc as carrier at 10 % moisture content. Shelf life studies revealed that chitosan was the best carrier material compared to talc in retaining viability of Metarhizium capsules, with a mean cfu of 2.51 × 107 mL-1 and 1.77× 107 mL-1. During a period of three months of storage, there was no decline in the number of viable colonies, cfu ranging from 1.72 × 107 mL-1 to 2.79 × 107 mL-1. . Storage under refrigeration had better retention of viability (2.63 × 107 cfu mL-1) than at room temperature (1.64× 107 cfu mL-1). In Beauveria capsules, the viability did not differ in both chitosan and talc based capsules. Here also, the number of viable colonies did not decline statistically, till three months of storage, with mean cfu values ranging from 1.85 × 107 mL-1 to 2.36 × 107 mL-1. In general, shelf life of capsules could be extended by two months when chitosan was used as the carrier material. Low temperature storage could also improve the shelf life by two months. Shelf life studies of gel formulations indicated that both Metarhizium and Beauveria gels exhibited high viability in chitosan at room temperature and under refrigeration. The mean number of viable colonies observed was 2.39 × 106 cfu mL-1 in chitosan based gels of Metarhizium and 2.17 × 106 cfu mL-1 in Beauveria gels. The number of viable colonies of Metarhizium and Beauveria observed throughout the experimental period did not vary significantly over three months of storage. The mean number of cfu being 2.26 × 107 mL-1 on the 15th day and 1.41 x 106 mL-1 on the 90th day . It was also inferred that chitosan when used for formulating gels could extend the shelf life of both organisms by one month. Pathogenicity test disclosed the affinity of M. anisopliae to rhizome weevil and B. bassiana to pseudostem weevil. Pot culture studies to evaluate chitosan and talc based capsules of B. bassiana revealed that both the capsules of Beauveria were effective as chlorpyriphos 20 EC 0.05% for pseudostem weevil, in prophylactic and curative methods. The damage index (DI) was one each and reduction in pest population was 91.67 % in prophylactic control and 91.67-100 % in curative control. Metarhizium capsules reduced the damage caused by rhizome significantly, but the reduction in pest population was only to the tune of 47-55 % in prophylactic and 50- 58 % in curative control. Chitosan based gel of Metarhizium tested against rhizome weevil, reduced the damage significantly (DI 46.67 and 30, in prophylactic and curative methods). The pest population was reduced by 61.11 % in prophylactic and 36.11 % in curative methods. The study could standardize the protocol for capsule and gel formulations of entomopathogenic fungi, retaining the viability and infectivity upto three months of storage. It is concluded that placement of Beauveria capsules in leaf axils prophylactically and curatively can effectively control pseudostem weevil and Metarhizium capsules and gels placed in the rhizosphere could manage the rhizome weevil moderately.ThesisItem Open Access Management of banana pseudostem weevil, Odoiporus longicollis (Olivier), using safe chemicals and bio-rational methods(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2017) Sivakumar, T; KAU; Jiji, TA study on ‘Management of banana pseudostem weevil, Odoiporus longicollis (Olivier), using safe chemicals and bio-rational methods’ was conducted at the College of Agriculture, Vellayani and in farmer’s field during 2012-2015. The main objective was to evolve strategies for managing the pest using safe chemicals and bio-rational methods. The study involved documentation of the pest status and farmers’ management practices, evaluation of the efficacy of different insecticides, botanicals and bio-agents under laboratory and field conditions and determination of harvest time insecticide residues in edible parts. Status of pests in banana was documented from Alappuzha, Pathanamthitta, Kollam and Thiruvananthapuram districts during 2013. O. longicollis incidence in banana cv. Nendran varied from 5.36 per cent in Kollam to 7.64 per cent in Pathanamthitta. Erionota sp., Bactrocera dorsalis (Hendel), Polytus mellerborgi (Boheman), Coccus hesperidum L. were observed as the emerging pests from the area. Pest management practices adopted by banana farmers, documented from the above districts, revealed the use of sixteen types of pesticides, including organic preparations. No specific parasite or predator was recorded from field except earwigs and red ants. Efficacy of insecticides, botanicals and bio-agents for the management of O. longicollis was evaluated under laboratory conditions. Thiamethoxam (0.01%), emamectin benzoate (0.002%) and cartap hydrochloride (0.1%) caused 100 per cent mortality of adults and grubs of the pest within 36 h after treatment. Among the botanicals, cassava leaf distillate based formulation, ‘Nanma’ (5%) caused 36.67 per cent mortality of adults and grubs, whereas neem soap caused 36.67 and 16.67 per cent mortality of adults and grubs, respectively. Among the bio agents tested, Metarhizium majus Bisch, Rehner and Humber (ICAR-CPCRI) 2% caused 80 per cent mortality of grubs on the seventh day of inoculation. Compatibility of insecticides, fungicides and botanicals with M. majus was tested using poisoned media technique. The fungicides viz., propiconazole (0.1%), tebuconazole (0.1%), mancozeb (0.3%) and carbendazim (0.1%) resulted in total growth inhibition of M. majus, while thiamethoxam (0.01% and 0.03%), cartap hydrochloride (0.05%) and neem soap (1.0%) were found compatible. Application methods of insecticides, botanicals and bio-agents were standardised through field experiment at the Instructional Farm, College of Agriculture, Vellayani during 2013-2014. Among the application methods, leaf axil filling (LAF) and injection of thiamethoxam (0.01% and 0.03%) recorded a yield of 10.98 and 10.88 kg plant-1, respectively. In the case of biopesticides, the highest yield (6.43 kg plant-1) was recorded with swabbing + LAF application of M. majus (20g l-1), whereas among botanicals, spraying +LAF gave the highest yield (8.8 kg plant-1) for neem soap (1.0%) application. Prophylactic and curative methods for the management of the pest, using thiamethoxam, neem soap, cassava leaf based preparation and M. majus, were tested in farmer’s field at Konni, Pathanamthitta district during 2014-2015. In prophylactic method thiamethoxam injection (0.03%) at 5th and 6th months after planting recorded an yield of 10.67 kg plant-1, followed by thiamethoxam (0.01%) leaf axil filling (10.32 kg plant-1) at 5th and 6th months after planting. Significantly higher value for BC ratio (2.44) was recorded for thiamethoxam (0.03%) injection. The BC ratio was 2.33 for thiamethoxam (0.01%) leaf axil filling. Application of M. majus (2%) at five months after planting, followed by thiamethoxam LAF (0.01%) at 6th month after planting yielded 8.82 kg plant-1. In curative method, plant survival was the highest (80 per cent) for thiamethoxam injection (0.03%). However, a low BC ratio of 0.86 was observed. Thiamethoxam injection (0.03%) and leaf axil filling (0.01%) were on par with chlorpyrifos (0.03%), as curative method. No detectable residue of thiamethoxam on any edible parts of the plant was observed at the time of harvest. To conclude, ‘Nendran’ was found to be the most susceptible banana cultivar to O. longicollis. Thiamethoxam at 0.01 per cent and 0.03 per cent were compatible with the entomopathogen, M. majus. Prophylactic method using thiamethoxam injection @ 0.03% and leaf axil filling @ 0.01%, both at five and six months after planting, were found effective, eco friendly and economical practice for O. longicollis management. The application of entomopathogenic fungi M. majus at five months after planting followed by thiamethoxam (0.03%) injection at six months after planting was also effective for managing the pest.ThesisItem Open Access Mass trapping of cowpea pod borer maruca vitrata (F.) (lepidoptera; pyralidae) using sex pheromones(Department of Agricultural Entomology, College of Agriculture, Padannakkad, 2018) Eurekha Savadatti; Sreekumar, K MA study was conducted know the efficacy of synthetic sex pheromone of legume pod borer Maruca vitrata (F.) (Lepidoptera: Pyralidae) at College of Agriculture, Padannakkad. Also investigated the female calling and mating behaviour of the adult moths of M. vitrata. Response of commercial lure to male moths of the test insect was studied in Electroantennogram at NBAIR, Bangalore. The commercial synthetic pheromone lure of legume pod borer M.vitrata from M/s Pest control India (P) Limited, Bangalore was tested and found that it failed to attract not even a single moth. Subsequently, the mating behaviour of the moth was undertaken in detail to investigate whether pheromones are involved in the mating process of the insect. 30 per cent of moths emerged during photophase (6am-5pm) out of which male moths constituted 36.25% and female moths constituted 23.75%. During scotophase (6pm-5am), 69.68% moths emerged, out of which 63.12% was males and 76.25% was females. The emergence found to peak at 5th and 9th hour of scotophase. During calling period female extrudes its pheromone gland beyond the abdominal tip. Female calling behaviour of one to eight day old moths was observed throughout the scotophase. A single calling peak was observed in all aged moths at 6 th hour of scotophase except for three old day moths, which showed additional peaks of calling at fifth, eighth and 9th hour of scotophase. For three-day-old moths, 43.5% was the mean percent of calling at 6th hour of scotophase. The mating behaviour of 1-8 day old M.vitrata moths involving 15 pairs throughout the scotophase showed maximum mating percentage of 26.2 % and 16.6 % for 3 day old and 2 day old moths respectively. Electroantennogram study conducted to know the response of 3-day-old male moths to synthetic lure obtained from PCI, Bangalore showed that response to the stimulus was 0.05mv only, which was the same for the solvent hexane and the air. 75 This showed that there was no distinct physiological response for synthetic pheromone lure. For further confirmation, GC-MS analysis was done and the compound E, E-10, 12-Hexadecadienal was identified at a retention time of 16.42 min. This is the major pheromonally active compound identified in previous studies. In GC- EAD analysis, the response of M.vitrata male moths to E, E-10, 12-Hexadecadienal was checked by matching EAD and FID peaks but without any response. So, the exact reason for the absence of response to commercial synthetic lure is to be elucidated in future studies for developing an effective commercial pheromone for the legume spotted pod borer M. vitrata.ThesisItem Open Access Insecticide mixtures for the management of pest complex in cowpea(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2018) Banka Kanda, Kishore Reddy; KAU; Ambily PaulA study on “Insecticide mixtures for the management of pest complex in cowpea” was undertaken in College of Agriculture, Vellayani and in the farmers field at Kalliyoor during 2016 to 2018. The main objectives were to evaluate the efficacy of insecticide mixtures having component molecules of different mode of action against pests of cowpea and to study the dissipation pattern of mixtures in cowpea pods. Major pests documented in the experimental field were sucking pests viz., pod bug, Riptortus pedestris Fabricius, cowpea aphid, Aphis craccivora Koch, spotted pod borer, Maruca vitrata Fabricius, and leaf eating caterpillar, Spodoptera litura Fabricius. Experiment was laid out in RBD to study the efficacy of insecticide mixtures viz., chlorantraniliprole 8.8 % + thiamethoxam 17.5 % SC @ 150 g a.i ha-1, lambda cyhalothrin 4.6 % + chlorantraniliprole 9.3 % ZC @ 30 g a.i ha-1, thiamethoxam 12.6 % + lambda cyhalothrin 9.5 % ZC @ 27.5 g a.i ha-1, beta cyfluthrin 8.49 % + imidacloprid 19.81 % SC 15.75+36.7 g a.i ha-1, flubendiamide 19.92 % + thiacloprid 19.92 % SC @ 48+48 g a.i ha-1, chlorantraniliprole 18.5 % SC +thiamethoxam 25 % WG (hand mixed) @ 1:1 @ 0.30 mL L-1 along with standard checks chlorantraniliprole 18.5 % SC @ 30 g a.i ha-1 and thiamethoxam 25 % WG @ 0.30 g L-1 against cowpea pests (Cowpea variety- Vellayani Jyothika). The results of the study revealed that chlorantraniliprole 8.8 % + thiamethoxam 17.5 % SC @ 150 g a.i ha-1 was found effective in managing the population of pod bug, R. pedestris, followed by followed by followed by followed by followed by thiamethoxam 12.6 % + lambda cyhalothrin 9.5 % ZC @ 27.5 g a.i ha-1 and beta cyfluthrin 8.49 % + imidacloprid 19.81 % SC @ 15.75+36.7 g a.i ha-1. Less incidence of bug was found in effective treatments after 7 days of spraying. More or less similar result was obtained in the management of cowpea aphid, A. craccivora. Less number of aphid was observed in the plants treated with chlorantraniliprole 8.8 % + thiamethoxam 17.5 % SC @ 150 g a.i ha-1, thiamethoxam 12.6 % + lambda cyhalothrin 9.5 % ZC @ 27.5 g a.i ha-1, chlorantraniliprole 18.5 % SC + thiamethoxam 25 % WG (hand mixed) @ 1:1 @ 0.30 mL L-1 and thiamethoxam 25 % WG @ 30 g a.i ha-1 against 211.67 aphids plant-1 in control after 15 days of spraying. Significantly higher reduction in leaf damage by S. litura was recorded in plants treated with lambda cyhalothrin 4.6 % + chlorantraniliprole 9.3 % ZC @ 30 g a.i ha-1 (25.03) which was on par with thiamethoxam 12.6 % + lambda cyhalothrin 9.5 % ZC @ 27.5 g a.i ha-1 (26.46) and chlorantraniliprole 8.8 % + thiamethoxam 17.5 % SC @ 150 g a.i ha-1 (30.20) 10 days after spraying. Whereas, in the management of cowpea pod borer, M. vitrata, less incidence of larvae was found in lambda cyhalothrin 4.6 % + chlorantraniliprole 9.3 % ZC @ 30 g a.i ha-1 and chlorantraniliprole 8.8 % + thiamethoxam 17.5 % SC @ 150 g a.i ha-1 treated plants after 5 days of spraying against 6.67 larvae in control. Dissipation of residues of these effective insecticide mixtures were studied by analysing the pods collected at 0, 1, 3, 5, 7, 10 and 15 days after treatment and the result showed that both the single insecticides in chlorantraniliprole 8.8 % + thiamethoxam 17.5 % SC were dissipated within ten days with half-lives of 5.34 and 3.01 respectively and in lambda cyhalothrin 4.6 % + chlorantraniliprole 9.3 % ZC, lambda cyhalothrin dissipated in five days and chlorantraniliprole dissipated in seven days with half-lives of 5.58 and 13.67 days respectively. The infestation of sucking pests, borers and leaf feeders simultaneously occur in cowpea especially in pod bearing stage. The results of the study revealed that spraying chlorantraniliprole 8.8 % + thiamethoxam 17.5 % SC @ 150 g a.i ha-1, thiamethoxam 12.6 % + lambda cyhalothrin 9.5 % ZC @ 27.5 g a.i ha-1 and lambda cyhalothrin 4.6 % + chlorantraniliprole 9.3 % ZC @ 30 g a.i ha-1 could effectively manage pest complex in cowpea with minimal or no risk to the consumers.ThesisItem Open Access Eco-friendly management of major pests of yard long bean, vigna unguiculata subsp. sesquipedalis (L.) Verdcourt.(Department of Agricultural Entomology, College of Agriculture, Padannakkad, 2018) Vineetha, V; KAU; Ramesha, BThe study entitled ′′Eco-friendly management of major pests of yard long bean, Vigna unguiculata subsp. sesquipedalis (L.) Verdcourt′′ was carried out in the Instructional farm of College of Agriculture, Padannakkad, Kasaragod during two seasons viz., kharif (May to August) and rabi (September to December) in the year 2016. The vegetable cowpea variety ‘Lola’ released by KAU was selected for the study. The study was undertaken with an intention to find out the efficacy of different microbial agents, neem based and biorational insecticides. The experimental design was RBD with 9 treatments and three replications. The treatments included; T1- Beauveria bassiana (liquid formulation @ 107 spores/ml of water), T2- Metarhizium anisopliae (liquid formulation @ 107 spores/ml of water), T3- Lecanicillium lecanii (liquid formulation @ 107 spores/ml of water), T4- Bt formulation 2× 108 cfu/ml @ 1 ml/l of water, T5- Neem based insecticide (Azadirachtin 1 per cent @ 5 ml/l of water), T6- Neem oil emulsion 5 per cent (50 ml/l of water), T7- Spinosad 45 SC @ 0.4 ml/l of water, T8- Malathion 50 EC @ 2ml/l of water (standard check), T9- Absolute control. All the treatments were imposed at fortnightly intervals just after the initial attack of pest was seen and observations were recorded at weekly intervals corresponding to standard weeks. The data were subjected to square root transformation and analyzed using ANOVA. After three consecutive sprays of Spinosad 45 SC @ 0.4 ml/l of water at fortnightly intervals there was complete reduction of pod borer larvae during kharif and rabi season. The percentage of flowers and pods infested by pod borer larvae were also reduced completely and no infestation was noticed after three consecutive sprays of Spinosad during both seasons. Thus it was found that Spinosad 45 SC was effective in reducing the number of pod borers, percentage of flowers infested and percentage of pods infested. During kharif season, Beauveria bassiana was found to be the most effective treatment in reducing the nymphs and adults of pod bugs with minimum number of 0.56 bugs per plant followed by 0.63 bugs in T5 compared to T9 with 7.46 bugs per plant after three consecutive sprays. During rabi season, Azadirachtin 1 per cent showed no incidence of pod bugs after three sprays and Neem oil 5 per cent consistently reduced number of bugs to zero on 15 days after third spray whereas T9 exhibited maximum number of 4.26 bugs/plant. The effect of Beauveria bassiana was lowered during rabi season. It might be due to the inability of Beauveria spores to germinate and cause infection during that season because of inadequate humidity. Azadirachtin 1 per cent incessantly lowered the per cent of pods infested by pod bugs to zero even after two sprays during both seasons and leaf miner attacked leaves was also found minimum in plot treated with Azadirachtin 1 per cent (0.63 leaves/plant) compared to T9 (7.12 leaves/plant). The aphid population on shoots and per cent of aphid infestation on shoots were found to be zero after three consecutive sprays of Lecanicillium lecanii at fortnightly intervals during kharif season. Lecanicillium lecanii also lowered the aphid population on pods and caused exorbitant reduction in the percentage of infested pods during both seasons after three sprays. Though pod length is an inheriting character, maximum length of 42.30cm and 48.40cm was shown by T7 during kharif and rabi seasons respectively. During both seasons viz., kharif and rabi, the total and marketable yield was high in T7 with highest benefit – cost ratio of 1.50 and 2.26 respectively.
