Pubescence as a plant resistance character against Spilosoma obliqua Walker in the interspecific crosses of soybean

Abstract

Spilosoma obliqua Walker (Lepidoptera; Arctiidae), a polyphagous insect often cause serious economic damage to several crops, particularly soybean (Glycine max (L.) Merr.). One wild accession Glycine soja is found to be resistant to this insect. An attempt was made to determine the relationship of the pubescence tip sharpness, length and density with resistance to S. obliqua with the help of'Scanning Electron Microscopy (SEM)’, and common compound microscope in the interspecific crosses between G. max and G. soja. The pubescence tip sharpness and pubescence density on the adaxial leaf surface of soybean were found to be important in determining resistance to S. obliqua but the length of the pubescence did not show any association with resistance to this insect. A comparison between the use of SEM and common compound microscope to identity pubescence types revealed that the common compound microscope can serve the purpose of distinguishing sharp tip and blunt tip pubescence types and whereby determining the resistant and susceptible cultivars of soybean to S. obliqua