Studies on Clonal Variation for Gall Midge, Asphondylia pongamiae Mani (Diptera: Cecidomyiidae) Infestation in Pongamia pinnata (L.) Pierre
Loading...
Date
2015-11
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
University of Agricultural Science, Dharwad
Abstract
Pongamia pinnata, oil producing tree legume, popularly known as ‘Karanja’ or ‘Honge’ which is widely occurring non-edible oil tree in India. Oil derived from the seed is a very good ‘bio-fuel’. Fifty three insect pests have been listed in P. pinnata which includes six species of gall inducers. The leaf gall inducing insect affect the growth of plants by reducing the leaf area available for photosynthesis. Aspondylia pongamiae (Diptera: Cecidomyiidae) which has been identified to induce flower and leaf galls on P. pinnata. These gall inducers adversely affect the quality of leaves of pongamia in turn reducing its economic utility. Experiments were conducted at the College of Forestry, Sirsi, during 2014-15.
Among the eleven clones evaluated, four clones, Hariharapura, Sathenahalli, Muddanahalli and Baragaru were found to be Moderately Resistant (MR) in both open and polyhouse conditions.
The growth performance of different pongamia clones as measured through plant height and collar diameter did not significantly vary due to infestation of gall midge. The difference in increases or decrease in growth parameter may be not due to gall midge infestation alone but may be due to phenotypic and genotypic variation among the pongamia clones because of their superior characters over the local seedling.
Among the four biochemical traits estimated, total phenol and potassium content in leaves did not show significant difference in infested and healthy leaves. However the clones which were moderately resistant had increased nitrogen content and reduced total soluble sugar under infested leaves than healthy leaves. Reduction in total sugar and increased nitrogen content in leaves could be a mechanism to resist the infestation of gall midge in P. pinnata.
Description
Keywords
null