The biochemical basis of resistance of some chickpea (Cicer arietinum L.) cultivars against gram pod borer (Helicoverpa armigera HB.)

The project under consideration was of utmost importance in context with the prevailing atmosphere of ever increasing infestation and damage from the side of insect pests to the crops accompanied with the development of resistance against insecticides among insects as whole. So to over come this condition it is needed to combat the situation wisely and evolve varieties having natural immunity against insects. This was the main core of aim of this project. As the project is a little bit of complex in nature in which initiation is open in the field that leads us to the environment of the laboratories to see the actual phenomena behind the resistance scenario i.e., the biochemical. The present investigations for finding out the biochemical basis of varietal resistance in chickpea against gram pod borer (Cicer arietinum) were undertaken during Rabi, 2001 at the Entomological Research Area, Ayub Agricultural Research Institute, Faisalabad. The experiment material was comprised of 8 grams varieties, which were evaluated for the source of resistance in biochemical terms. Design was randomized complete block design with three replications. Proper and due care was provided to the crop and all cultural practices were undertaken. The attack of gram pod borer was quite late and it appeared in first week of March and the attack was of very less severity in nature, however, it provided a mechanism study of tile biochemical in the phenomena of resistance. The data of the pod damaged in each treatment of each replication were recorded on weekly basis for five times. The mean pod damage was calculated on the basis of this data. At the end of the first phase of the research harvesting was done. The biochemical were analyzed in the laboratory. The analysis of chemicals was a second phase of the research. The oxalic acid, reducing sugars, non- reducing sugars, cellulose, hemicellulose, lignin, ash, silica, acid detergent fibre (ADF) and neutral detergent fibre (NDF) were analyzed. Statistical analysis was done to locate the relationship between the pest damage and the biochemical present in the chickpea plant. On the basis of the statistical analysis it was found that the variety 96052 was highly result to gram pod borer followed by 96051, 97047, Pb-6-5, Pb-2000, 9075, 90395-K and 88194, respectively. The biochemical considered as responsible for the induction of resistance in chickpea were all present in moderate quantity in 96052 with particularly large amount of lignin, which is considered as a cementing material used in the development of cell wall. The susceptible variety was found to be consisting of more ash contents as compared to other varieties. The medium varieties showed all biochemical in moderate form especially the oxalic acid, which was almost of same quantity in all varieties with a little difference. On the basis of the research carried out in the quest of biochemical which determine the magnitude of the resistance in chickpea against gram pod borer, it may be concluded that varieties with the highest amount of lignin should be developed accompanied with high concentration of the oxalic acid, cellulose, hemicellulose ADF etc. to compete the increasing alarm of gram pod borer resistance against pesticides due to which every year new pesticides are being imported which not only pollute our environment but are also hazardous to crops and ultimately the consumers of the including mankind.