Traits Affecting the Resistance of Rice Genotypes to Rice Stem Borer

Rice is one of the most important staple food crops for more than half of the world’s population. The striped stem
borer [Chilo suppresalis (walker)] is one of the most devastating pests of rice, reducing yield world wide. The
use of resistant cultivars remains one of the most reliable methods to pest's management. In this study the
mechanism of resistance in 10 rice lines for three kinds of resistance (antixenoses, antibioses and tolerance) in
greenhouse and farm were studied. The egg mass of striped stem borer on the leaf for antixenoses resistance,
larva weight mean and survival percentage of larva were evaluated for antibioses resistance. Percentage of white
head was used for estimation of tolerance to striped stem borer. The results showed that line of 3 had the highest
egg mass, larva survival percentage, dead heart and white head and line of 5 had the highest larva weight mean.
In this study line of 3 and line of 4 were the most susceptible and tolerant genotypes, respectively. Results of this
study showed that by mechanism of tolerance were affected the plant height and amount of chlorophyll on
antixenoses mechanism, stem diameter and number of tiller on antibioses mechanism and stem diameter.