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ThesisItem Open Access Cashew nut shell liquid (CNSL) formulation for the management of banana Pseudostem weevil, Odoiporus longicollis (Oliver)(Department of Agricutural Entomology, College of Agriculture, Vellayani, 2020) Archa S, Nair.; KAU; Fazil, M HThe study entitled “Cashew Nut Shell Liquid (CNSL) formulation for the management of banana pseudostem weevil, Odoiporus longicollis (Olivier)” was undertaken in the Department of Agricultural Entomology, College of Agriculture, Vellayani during 2018-20 with an objective to evaluate Cashew Nut Shell Liquid formulation (CNSL 20% EC) for the curative management of the pest. Cashew Nut Shell Liquid (CNSL), a potential insecticide and a cheap by- product of cashew industry, was formulated into an emulsifiable concentrate formulation (CNSL 20 % EC) in the Department of Agricultural Entomology, College of Agriculture, Vellayani was tested against O. longicollis. Different concentrations viz. CNSL @ 0.5, 0.75, 1, 2, 3, 4 and 5 % were evaluated against third instar grubs of O. longicollis under laboratory conditions. Grubs treated with lower concentrations of CNSL (0.5 % and 0.75 %) were found to be dead with bloated body without any discolouration. At concentrations of 1%, 2% and 3%, they were found to be dead with black discolouration of the abdominal region. At the higher concentrations (4 and 5%), the grubs were found dead, shrunken and constricted. Higher concentrations of CNSL (4% and 5%) was found to cause mortality of 93.33 per cent which was on par with that of chemical check, thiamethoxam 0.01 % and neem oil emulsion 3%. CNSL @ 3 % caused mortality of 86.67 per cent and was on par with the higher concentrations of CNSL. The LC50 and LC90 values of CNSL against O. longicollis was found to be 0.52 and 3.71 per cent respectively at 3 days after treatment. CNSL concentrations viz. 1.85 % (0.5 LC90), 3.7% (LC90), 7.4% (2 LC90) and 0.5% (LC50) applied on pseudostem pieces were evaluated along with botanicals, Nanma 5 %, neem oil emulsion 3% and pongam oil emulsion 1% to ascertain the repellent effect on adult weevils in multiple choice and no choice test. The adults were found to be highly reluctant to Nanma 5% and neem oil 3% in the initial hours (1 to 5 HAT) of treatment in the multiple-choice test with no weevils getting settled on them. CNSL treatments @ 3.7 and 7.4 % were found to be less attractive to the weevils with only 3.33 to 5.83 per cent of the weevils moving towards them initially. 7.5 to 12.5 per cent of the weevils moved towards pseudostem pieces treated with CNSL @ 0.5 and 1.85 %. Upon longer exposure 7.4 % was the least preferred among the CNSL treatments with only 1.67 per cent of the weevils remaining on it at 24 HAT which was found superior to Nanma 5% and neem oil 3%. When no choice was given, initially (1 to 5 HAT), less number of weevils (0 to 26.67 per cent) moved towards to CNSL treated pieces irrespective of the concentration as compared to untreated check (46.67 to 93.33 per cent). Large number of weevils (93.33 to 100 per cent) were found to settle on pseudostem pieces treated with CNSL @ 0.5 to 3.7 % as against less numbers in Nanma 5% and neem oil 3% (60 to 66.67 per cent) at 24 HAT. CNSL @ 7.4 % attracted only 73.33 per cent weevils and was found to be superior comparable to treatments with Nanma and neem oil. Banana plants uniformly infested with pseudostem weevil were applied with CNSL @ 0.5, 1 and 3.7 % following two methods of application viz. leaf axil filling (250 mL plant-1) and stem injection (20 mL plant-1). Menma 15 mL/plant injection served as the botanical check and stem injection with thiamethoxam 0.03 % as the chemical check. The number of bore holes, mean vertical and horizontal damage produced by the pest and the number of live insects retained were assessed by destructive sampling. No phytotoxicity was observed. CNSL @ 3.7 % and 1% both as stem injection and leaf axil filling produced an effect on par with other treatments with respect to number of bored holes plant-1. Similarly the number of live grubs were also low in CNSL treatments @ 3.7% stem injection (4.33 grubs plant-1) followed by 1% CNSL stem injection (10 grubs plant-1), 3.7% CNSL leaf axil filling (11.33 grubs plant-1) and 1% CNSL leaf axil filling (12.67 grubs plant-1) which were on par. Stem injection with 3.7 % CNSL was found to be superior in managing the pseudostem weevil with reduced number of bore holes (49.33 plant-1), number of insects (4.33 grub plant-1, 5 pupae plant-1and 2.33 adults plant-1) and mean vertical and horizontal damage (31.63 cm sheath-1 and 18.3 cm sheath-1). The per cent reduction over control was found to be 18.69, 54.07, 66.01 and 76.81 respectively for number of bore holes per plant, mean vertical and horizontal damage and number of live grubs retained per plant. This treatment was found to be as effective as stem injection with thiamethoxam 0.03 % and Menma 15 mL plant-1 for the curative management of banana pseudostem weevil. CNSL 20% EC @ 3.7 % leaf axil filling and 1 % both as stem injection and leaf axil filling also could reduce the damage by BPW comparable with CNSL 20% EC @ 3.7 % injection with low vertical damage (45.99 to 47.19 per cent reduction over control) as well as horizontal damage (54.67 to 55.66 per cent reduction over control). However, among these treatments leaf axil filling with 1% CNSL 20% EC gave better protection from probing and oviposition as evidenced by 21.43 per cent reduction of number of bore holes over control as against 4.4 to18.69 noted in other CNSL treatments, making it ideal for prophylactic control. Thus, application of CNSL 20% EC 1% both through leaf axil filling and stem injection and CNSL 20% EC 3.7 % leaf axil filling are successful in significantly reducing the population and damage by O. longicollis over untreated check though inferior to 3.7 % stem injection. Leaf axil filling treatment with 1 % CNSL and 3.7 % CNSL 20% EC were at par in reducing the population and damage. Thus, CNSL 20% EC 3.7 % stem injection (20 mL plant-1) and 1 % CNSL leaf axil filling can be resorted to, for the eco-friendly management of pseudostem weevil with the former being more effective for curative treatment.ThesisItem Open Access Management of banana pseudostem weevil odoiporus longicollis oliv.using entomopathogenic fungi(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2005) Sahi Beegum, M K; KAU; Anitha, NInvestigation on “Management of banana pseudostem weevil, Odoiporus longicollis Oliv. using entomopathogenic fungi” was carried out in the Department of Agricultural Entomology, College of Agriculture, Vellayani. The study was conducted to screen four entomopathogenic fungi, to evaluate their biocontrol potential and to standardize the effective dose and method of application for the management of the banana pseudostem weevil. Four entomopathogenic fungi viz., Metarhizium anisopliae, Beauveria bassiana, Paecilomyces lilacinus and Nomuraea rileyi were tested against O. longicollis. Among them M. anisopliae and B. bassiana were found to infect O. longicollis grubs. Susceptibility of different stages of grubs to fungal infection was tested by using first, second, third, fourth and fifth instar grubs of O. longicollis and the results revealed that first and second instar grubs were more susceptible to fungal infection. Determination of effective dose of fungi against second instar grubs of O. longicollis was carried out by spraying the grubs with different concentrations of M. anisopliae and B. bassiana. The LC50 values of M. anisopliae and B. bassiana were 3.9 x 106 spores ml-1 and 1.6 x 105 spores ml-1 respectively. Evaluation of six naturally available solid media viz., rice bran, wheat bran, guinea grass, gingelly oil cake, coir pith, and neem cake were carried out for mass multiplication of M. anisopliae and B. bassiana. The results revealed that both rice bran and wheat bran were suitable for the mass multiplication of these fungi. The spore production was 9.26 x 106 spores ml-1 and 8.71 x 106 spores ml-1 respectively for M. anisopliae on first week after inoculation. For B. bassiana, the spore count was 503.42 x 106 spores ml-1 and 320.32 x 106 spores ml-1 respectively on first week after inoculation. Among the liquid media tried, coconut water and rice bran extract produced maximum mycelial growth and sporulation of fungi. For M. anisopliae the spore count was 7.77 x 107 spores ml-1 and 0.49 x 107 spores ml-1 respectively. B. bassiana recorded 440.03 x 106 spores ml-1 and 232.26 x 106 spores ml-1 respectively. M. anisopliae and B. bassiana grown in rice bran and wheat bran recorded maximum virulence on two weeks after storage and decreased thereafter. However, coconut water and rice bran extract showed maximum virulence on first week after storage and then found decreasing. Studies conducted to evaluate the compatibility of fungi with NeemAzal 0.4 per cent, chlorpyriphos 0.03 per cent, copper oxychloride 0.4 per cent and mancozeb 0.3 per cent revealed that all the pesticides tested inhibited the growth of M. anisopliae and B. bassiana. But the per cent inhibition was least in the case of NeemAzal 0.4 per cent. Field experiments were conducted with M. anisopliae and B. bassiana with chlorpyriphos (0.03 per cent) and NeemAzal (0.4 per cent) as checks. The plants were artificially infested with known number of grubs. Two experiments were conducted, one with prophylactic treatments and the other with curative treatments. Three application methods viz., leaf axil filling of spore suspension of M. anisopliae and B. bassiana, leaf axil filling of fungi in rice bran and stem injection of spore suspension were tested. Among these treatments leaf axil filling of B. bassiana spore suspension at 1.8 x 107 ml-1 as prophylactic treatment was most effective which gave 52.42 per cent mortality of grubs.ThesisItem Open Access Chemodynamics of Carbofuran in Cucumber(Department of Entomology, College of Agriculture,Vellayani, 1993) Anil Abraham, KAU; Naseema Beevi, SA field experiment was conducted to study the chemodynamics of carbofuran in cucumber plants when applied as granule in the soil. The insecticide was applied at two doses of 0.5 and 1.5 kg ai/ha at three occasions viz. sowing, vining and flowering stage of the crop. The residues of carbofuran and its metabolites were estimated from the vines, leaves and fruits at different intervals after the insecticidal treatment using gas chromatographic technique. Distribution of the residues in the various portions of fruit and the effect of different periods of storage on the degradation of residues were also studied in detail. A safe waiting period was also arrived so as to avoid residue hazards in consumption of the fruits. The results indicated that absorption and metabolism of carbofuran in the plant begins soon after its application in the soil. Pure carbofuran and the metabolites, 3-OH carbofuran and 3-keto carbofuran were detected in the vines, leaves and fruit samples at 1,3,7,14,21 and 28 days after treatment. When the different portions of the plant were analysed, the highest level of residues was detected at different occasions. Thus in the vines the peak level of residues was seen on the first day after treatment where as in the leaves and fruits it was on the third seventh day respectively. A gradual decline was noticed thereafter and the residues reached almost non – detectable by 28th day after treatment in all parts of the plant. The effect of peeling on residues was studied in a separate experiment and the results indicated that peeling of fruits could reduce the residues considerably. Distibution of carbofuran residues in different fruit portions was studied and the results indicated that maximum accumulation of the residues took place in the top portions of the fruit followed by middle and basal portions. Comparing the carbofuran residues in the flesh and placenta of cucumber fruits when treated at the flowering stage of the crop it was observed that maximum accumulation of residues of carbofuran took place in the flesh portion when compared with the placenta of the fruit (inner core and seeds). Effect of storing the fruits on the degradation of carbofuran residues showed that metabolism and degradation of the chemical continued even after harvest, during the process of storage. For safe consumption of fruits following carbofuran treatment at the flowering stage a waiting period of 25 and 26 days have to be given when applied @ 0.5 and 1.5 kg ai/ha respectively.ThesisItem Open Access Effect of organic amendments on plant parasitic nematodes and soil micro-organisms(Department of Entomology, College of Agriculture, Vellayani, 1992) Ajith, K; KAU; Sheela, M SField experiments conducted to evaluate the effect of neem and eupatorium leaves at two levels on plant parasitic and non-parasitic nematodes and soil micro-organisms in the rootzone of bhindi and cowpea in rainy and summer seasons revealed that neem and eupatorium leaf treatments (300g/plant or 15 t/ha) were found effective in controlling Helicotylenchus spp., R. reniformis and M. incognita in the rootzone. Lower dose (150g/plant) of neem was found sufficient to suppress the Helicotylenchus spp. In the rootzone of bhindi. Effect of these treatments persisted up to 75 D A S in rainy season and 45 DAS in summer season. The effect of lower doses also persisted up to 30 DAS. The predatory and saprophytic nematode population build up in the rootzone was enhanced by higher dose of eupatorium. The effect on predatory fauna persisted up to 75 D A S in the rootzone of two crops. But in cowpea the effect on saprophytic fauna persisted only up to 60 D A S. The microbial populations (bacteria, fungi and actinomycetes) were increased in the rootzone of bhindi and cowpea in two seasons by the application of eupatorium leaf at higher dose where as neem leaf (higher dose) reduced the microbial population. Only the fungal population increased by the application of neem leaf at higher dose during rainy season. There was seasonal variation in population build up of fungi and maximum effect was seen in rainy season. The biometric characters (number of leaves, height of plant, root weight and shoot weight) and yield of bhindi and cowpea increased significantly by the higher dose of neem and eupatorium leaf. For increasing the height, lower dose of neem, and, for yield lower dose of neem and eupatorium also were found effective. The population of nematodes in the roots at the termination of experiment was significantly reduced by the higher dose of neem and eupatorium in bhindi while lower dose was found effective protecting cowpea roots.ThesisItem Open Access Biological activity of different plant extracts with particular reference to their insecticidal,hormonal and antifee ding actions(Department of Entomology, College of Agriculture, Vellayani, 1989) Saradamma, K; KAU; Mohan Das, NTwenty locally available plants were screened for their antifeedant activity against three important crop pests of Kerala using water, acetone, benzene and petroleum other as extractants. Benzene was, in general, the best extractant and as a test insect H. vigintioctopunctata was more sensitive than S. litura or P. ricini. Among the twenty plants screened all the extracts of C. infortunatum, A.indica, T.neriifolia and E.odoratum and benzene and ether extracts of N.oleander gave high leaf protection against H.vigintioctopunctata. Against S.litura benzene and ether extracts of C.infortunatum, A.indica, T.neriifolia and N.oleander were effective. Water extract of E.odoratum and acetone extract of C.infortunaturm, A.indica and T.neriifolia also had high antifeedant activity against S.litura. All extracts of A.indica and water, benzene and acetone extract of N.oleander had antifeedant effect on P.ricini. High larval starvation was caused by most of the plant extracts which showed antifeedant action. But some extracts ineffective as antifeedant also caused high larval starvation. Eight essential oils obtained from the country were screened for feeding deterrency against P.ricini. Citronella oil, geranium oil and camphor oil gave significant protection, but the dosages required were too high to indicate possibilities of practical exploitation of essential oils as antifeedants for pest control. Based on PC 95 values worked out through bioassay studies using H.vigintioctopunctat as test insect N.oleander ranked first as antifeedant. It was followed by C.infortunatum, A.indica, T.neriifolia and N.odoratum. Based on larval starvation these plants had different ranking. Antifeedant activity of the extracts of T.neriifolia and N.oleander persisted up to 22 days on brinjal on field while that of C.infortunatum, E.odoratum and A.indica persisted up to 18 days. On the basis of PT indices the treatments were ranked as water extract of T.neriifolia > benzene extracts of N.oleander > C.infortunatum > E.odoratum > A.indica. The insecticidal effects of the plant extracts on D.cingulatus, H.vigintioctopunctata and S.litura were low. However, extracts of A.indica, T. neriifolia, P.odoratissimus and C.gigantea showed significant toxicity to A.craccivora. But their LC 50 values ranged from 34 to 93 per cent. Benzene extracts of C.infortunatum, A.indica, T.neriifolia and E.odoratum had high systemic action on different nymphal instars of D.cingulatus. Fourth instar nymphs were more tolerant to the insecticidal action of the extracts. The essential oils included in the experiment did not show insecticidal activity on D.cingulatus and S.litura while some caused significant mortality of A.craccivora at high doses. Sixteen out of twenty plants tested had significant juvenomimetic effect on D.cingulatus in one or more than one of the extracts tested. When the different extracts were ranked on the basis of percentage of normal adults and their sterility (an index of the possible build up of the post treatment populations of the test insect) benzene was found to be the best and it was followed by water while acetone and ether were on par and far less effective. T.neriifolia, A.indica and E.odoratum caused 100 per cent sterility of D.cingulatus in water and benzene extracts and above 90 per cent sterility in other two extracts. C.infortunatum and N.oleander caused 100 per cent sterility in acetone, benzene and water extracts. The juvenomimetic effect of S.litura was much lower than that on D.cingulatus. All the extracts of A.indica and N.oleander, water and acetone extracts of T.neriifolia and V.negundo, benzene and acetone extracts of A.vesica, acetone extract of E.odoratum, ether extract of M.esculenta and C.variegatum caused 100 per cent sterility to the insect and hence the treatment would limit the contribution from the treated insects to the next generation to zero level. Bioassay studies showed that acetone extracts of C.infortunatum had highest juvenilising effect on D.cingulatus. It was closely followed by A.indica. T.neriifolia, N. oleander and E.odoratum were much less effective than A.indica and C.infortunatum. Benzene extracts were more active than acetone extracts and were ranked as A.indica > C.infortunatum > N.oleander > E.odoratum > T.neriifolia. Considering both the extracts C.infortunatum came on par with A.indica. N.oleander and E.odoratum were also found promising. The essential oils caused morphogenetic abnormalities in the developing numphs of D.cingulatus. The dosage at which high sterility could be obtained were too high to ensure economic viability of its use in field. Lower effective dosages, cheaper and comparably effective oils may have to be found out for wide use of essential oils for pest control. Benzene extracts of A.indica, E.odoratum, C.infortunatum, T.neriifolia and N.oleander and water extracts of T.neriifolia as 2% emulsions reduced the populations of H.vigintioctopunctata, C.insolitus and A.gossypii on brinjal and H.vigintioctopunctata on bitterground significantly in the field experiments. All the treatments (except T.neriifolia againist A.gossypii) came on par with the insecticide check, carbaryl 0.2 per cent suspension, in reducing the population. The studies have thus established that the antifeedant and juvenoid effects of five plants screened out from the local flora were as promising as those of A.indica, the well recognized plant source for such activity and the extracts of these plants can be exploited effectively in the integrated control of crop pests.ThesisItem Open Access Ecofriendly pest management in Brinjal (Solanum melongena L.)(Department of Entomology, College of Agriculture,Vellayani, 2000) Annie Bernice, T S; KAU; Krishnakumar, RA survey was conducted in the important brinjal growing tracts of Thiruvananthapuram district to study the population dynamics of the pests and their natural enemies in the brinjal ecosystem. Laboratory experiment and field experiments were conducted in the College of Agriculture, Vellayani to assess the deterrency and toxicity of the different treatments on aphids, epilachna and Leucinodes which were identified as important pests of brinjal from the survey and the effective treatments as identified from the laboratory experiment were carried out in the field. =<; Malathion alone or with garlic was found to be toxic to aphids. Epilachna and Leucinodes. The treatments with neem oil and Hyptis suaveolens either alone and in combination were found to have deterrent and toxic effects on aphids, Epilachna and Leucinodes in the laboratory experiment. However, the effect was much pronounced when neem oil activated with garlic was used in combination with Hyptis suaveolens. In the field, though malathion was found to contain the pests, the effect was not persistent for a long time and hence was not effective in the long run. The combination of neem oil + garlic plus Hyptis suaveolens was found to offer protection for the pest for a long period of time. On par with it were combination of nee m oil plus Hyptis suaveolens + garlic and combination of neem oil + H. suaveolens. The botanicals were also found to be safe for the natural enemies like coccinellids, staphylinids and spiders. This treatment was also found superior to other treatments in terms of net income and benefit cost ratio and the lower unit cost of the treatment with high yield was precisely the reason for its superiority.ThesisItem Open Access Evaluation of Bacillus thuringiensis Berliner for the management of rice leaf folders(Department of Agricultural Entomology, College of Horticulture,Vellanikara, 1998) Asha, R; KAU; Babuphilip, MThe study was conducted with the objective of survey and identification of the natural enemies of leaffolder and other lepidopterous pests of rice and to evaluate the efficacy of B. t. formulations against the leaffolders of rice. The survey was conducted at the Agricultural Research Station, Mannuthy and the Kerala State Agricultural Department Seed Farm, Mannuthy. The field trials to evaluate the efficacy of rice leaffolders were conducted at the Agricultural Research Station, Mannuthy during Kharif 1995 and Kharif 1996 . .. The present study revealed the occurrence of five viroses, two bacterioses and a nematode infection in the various lepidopterous pests of rice. Four Braconids, three Ichneumonids one Eulophid, one Chalcid and a Bethylid parasite were also recorded from various lepidopterous pests of rice. The B.t. formulations tested were found to be effective against the leaf folders on rice. The percentage of leaf damage during Kharif 1995 showed the B.t. formulations Biotox, BTT, Biolep to be the best treatments. With respect ~to the grain yield, BTT was the best treatment followed by Dipel, Biolep and Biotox. During Kharif 1996, Dipel followed by Biotox and monocrotophos were found to be the best in terms of percentage of leaf damage. Based on the yield during 1996, BTT was found to be the superior one followed by monocrotophos. B. t formulations were found to be safe to predatory spiders, other predators and paras i toids of folders. the leaf The combination of BTT and C.m. GV was able t.o reduce the leaf damage and data on larval mortality showed the leaf folder larvae to be susceptible to the combination of BTT and C.m. GV. The GV of C. medinalis was found to be highly host specific.ThesisItem Open Access Integrated control of fruit fly Dacus cucurbitae Coq: Trypetidae: Diptera on bitter gourd(Department of Entomology, College of Agriculture, Vellayani, 1989) Jalaja, P N; KAU; Remamony, K SBittergourd is very popular among the vegetable growers in Kerala. Fruit flies take a heavy toll of this crop and intense use of pesticides is a common practice of cultivators often leading to serious residue hazards in the marketed fruits. In the present investigation an attempt was made to standardise non-insecticidal methods of control for tackling this pest problem. Laboratory evaluation of potential attractants of fruit flies viz. eugenol, eucalyptus oil, citronella oil, borar, ammonium phosphate, vanilla essence, jaggery, sugar, vinegar, honey, toddy and bittergourd fruits were screened for baiting the adults of D. cucurbitae. Eugenol, eucalyptus oil, citronella oil, borax, ammonium phosphate and vanilla essence did not show any attractiveness to the flies. Three graded concentrationsof honey, sugar, jaggery, toddy and vinegar were tested for their attractiveness to the files in the laboratory. The result showed that (1) honey at the highest concentration of 1% attracted the maximum number of flies (2) toddy was not effective for attracting D. cucurbitae. (3) immature stages of bittergourd fruits showed poor aatraction and (4) ripe bittergourd fruits showed poor attraction and (4) ripe bittergourd fruits showed maximum attraction to the files up to 12 h of exposure.ThesisItem Open Access Use of synthetic pyrethroides for the control of pests of bitter gourd (Momordica charantia L) and snake gourd (Trichosanthes anguina L)(Department of Entomology, College of Agriculture, Vellayani, 1982) Kosaraju Ravindra, Nath; KAU; Sasidharan Pillai, KIn a field experiment conducted at the Instructional Farm, College of Agriculture, Vellayani, during the summer season in 1982, the efficacy of four synthetic pyrethroids viz. permethrin, fenvalerate, cypermethrin and deltamethrin, on the pests of bitter gourd and snake gourd in comparision with the standard, malathion, was evaluated. Both the crops were sprayed thrice on need basis for controlling the various pests which infested the crops at different growth stages. Spotted beetle observed on bitter gourd at the time of first spraying was controlled by all the synthetic pyrethroids along with the standard for a period of 23 days after spraying. Fruit fly of the bitter gourd also was controlled by all the three sprayings and all the insecticides were effective in most occasions. Cypermethrin at higher dose was superior to the standard during the first spraying followed by fenvalerate and deltamethrin. In the second spraying deltamethrin was not so effective whereas permethrin was found more effective. Again in the third spraying deltamethrin and fenvalerate were more effective . The fruit fly damage observed for the entire crop season revealed the superiority of fenvalerate, permethrin and deltamethrin at their higher doses over the standard. Jassid on bitter gourd was controlled by all the insecticides except permethrin and cypermethrin at their lower dose for a period of 2 days after the spraying . But aphid could be controlled only with permethrin and fenvalerate at their higher dose along with the standard malathion for a period of 2 DAS. The fruit set and the flowering pattern were not affected by any of these insecticides.