PG Thesis

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Standardization of tree injection procedures of Azadirachtin in coconut (Cocos nucifera L.), mango (Mangifera indica L.) and neem (Azadirachta indica A Juss.)
(Department of Forest Products and Utilization, College of Forestry,Vellanikkara, 2019) Sarmishtra, V; Anoop, E V
Tree injection is a new technology that is employed to apply fungicides, nutrients and pesticides in large trees in order to avoid drifting of these chemicals and affecting non target organisms. It eliminates the wastage of chemicals to be applied in trees as the quantity used is little compared to other conventional methods of application. This study aimed at standardizing the tree injection procedures in Indian conditions. Stem wood of three species like coconut (Cocos nucifera L.), mango (Mangifera indica L.) and neem (Azadirachta indica A. Juss.) were used in the study along with their leaves after the application of azadirachtin through injection. The depth to which the tree injection can be applied was determined by studying the thickness of the conducting tissues in these species using the software Digimizer. Three size classes like 50-60cm, 60-70cm, 70-80cm were studied. Thickness of high density wood in coconut palm and sapwood in mango and neem does not vary with the change in size class. Average high density wood thickness in coconut palm was 3.5cm and was not more than 4.89cm. Thus a depth of 6 cm was fixed so as to ensure the delivery of chemicals into the most active part of the stem. In case of mango tree, the average sapwood thickness was 6.18cm and was never smaller than 3.27cm. Similarly, average sapwood thickness in neem was 4.38cm and was never smaller than 3.02cm. Thus 3 cm was the depth fixed to inject chemicals in mango and neem. Systemic insecticide, Azajet (50,000ppm) was used to inject the trees. Each tree was marked at a basal height of 20 cm from ground. Holes were made at an angle of 45º to make sure that there was no oozing out of chemicals. The EcoJect pump consisting of a canister, nozzle and a cylinder with compressed air between 100 and 150 PSI was used to inject the chemicals. Two canisters of 20 ml each (40ml/tree) were used to deliver the chemical into the tree trunk. Physiological parameters like photosynthesis, transpiration, leaf temperature and leaf moisture were analyzed using Infrared Gas Analyzer (LI-6400, Portable Synthesis System). Stomatal rate was studied by the replica method. A correlation analysis was conducted between the anatomical and physiological properties of the three tree species. The traces of azadirachtin in the leaves were determined by collecting the leaf samples during specific time intervals like 1hr, 2hr, 6hr, 2 days, 7 days, 14 days, 20 days, 28 days, 40 days and 55 days of tree injection by using High Performance Liquid Chromatography (HPLC). There were no correlations between the anatomical and physiological parameters. Azadirachtin traces were found only in coconut palm on the second day of injection with a peak area of 0.14µg/g. Other trees showed no sign of azadirachtin in their leaves. The traces of the bio pesticide did not last for a week as there was no further detection of azadirachtin in the samples collected after 7 days of injection.
Evaluation of bacillus thuringiensis berliner for the management of rice leaf folders
(Department of Agricultural Entomology, College of Horticulture,Vellanikara, 1998) Asha, R; Babu Philip, M
The 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.
Eco-friendly management of major pests of upland rice ecosystem
(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2018) Shobha, Y B; Suja, G
Management of American serpentine leaf miner Liriomyza trifolil (burgess) dietars in tomato
(Department of Agriculture Entomology, College of Agriculture, Vellayani, 2017) Mithra Mohan; Anitha, N

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