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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 Exploration of the feasibility of developing races of trichograma Australicum girault ( trichogramatidar, hymenoptera) suitable for different environments(Division of entomology ,Agricultural college and research institute ,Vellayani., 1970) Abraham, C C; KAU; Pradhan, SThesisItem Open Access Evaluation of the toxicity of O,O-diethyl-thiono phosphoric acid O (quinoxalyl (2) ester (sandoz insecticide-6538)to insect pests(Division of entomology ,Agricultural college and research institute ,Vellayani., 1970) Gopinathan Nair, P; KAU; Nair, M R G KThesisItem Open Access Control of nematode parasites of brinjal with insecticide and nematicide granules(Division of entomology ,Agricultural college and research institute ,Vellayani., 1970) Vergis, P C; KAU; Mohas Das, NThesisItem Open Access Studies on the parasitic nematodes associated with vegetables in kerala(Division of entomology ,Agricultural college and research institute ,Vellayani., 1968) Ramakrishnan Nair, N; KAU; Mohan Das, NThesisItem 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 Studies on the rice swarming caterpillar , Spodoptera mauritia boisduval in Kerala(Division of entomology ,Agricultural college and research institute ,Vellayani., 1967) Thomas, B; KAU; M R G K NairThesisItem Open Access Studies on the effect of plant nutrient on insect infestation on Abelmoschus esculentus monech(Division of entomology ,Agricultural college and research institute ,Vellayani.Trivandrum, 1967) Viswanath, B N; KAU; M R G K NairThesisItem Open Access Studies on the toxtcity of insecticide to residues on brinjal to Epilachna vigintioctopunctata fabricius(Division of entomology, Agricultural college and research institute, Vellayani, Trivandrum., 1965) Kunjamma Mathew, P; KAU; M R G K Nair
