Relative Biochemical Basis of Susceptibility in Commercial WheatVarieties against Angoumois Grain Moth, Sitotroga cerealella (Olivier) andConstruction of its Life Table

Abstract

A study was conducted to evaluate the relative biochemical basis of susceptibility of six commercial wheat varieties grown in Khyber Pakhtunkhwa, Pakistan, against angoumois grain moth, Sitotroga cerealella (Olivier) (Lepidoptera: Gelechiidae) and construction of its life table at 28 ± 1°C, 65 ± 5 R.H.% and L:D 16:8 hours under laboratory environment. The results were evaluated on the basis of mean pest S. cerealella emergence, percent damage, and percent weight loss, male and female emerged along susceptibility index, 1000 grains weight, hardness and chemical composition of test wheat materials. Life table parameters of S. cerealella on highly susceptible and least susceptible wheat varieties were compared. On the basis of susceptibility index, variety Sirin (5.002) was recorded least susceptible and variety Pirsbak-2005 (7.832) recorded as highly susceptible. The chemical composition based on protein and carbohydrate contents (11.15%, 72.54%) revealed that the variety Sirin was recorded least susceptible, while variety Pirsabak-2005 (12.68%, 75.00%) was noted as highly susceptible. On the basis of life table, the net reproductive rate (10.9) on variety Pirsabak-2005 was higher than variety Sirin (9.4), and the intrinsic rate of increase was also higher on Pirsabak-2005 (30.7) than Sirin (15.9). With respect to doubling time being index of resistance, this time in Pirsabak-2005 was almost half (0.01 days) of the Sirin (0.02 days), which means that S. cerealella can develop more quickly on Pirsabak-2005 germplasm. In summation, relatively least susceptible wheat variety Sirin can be used to increase the level and diversify the basis of resistance to S. cerealella in the resistance breeding programs.