Screening Maize Genotypes for Resistance to Stem Borer, Chilo partellus (Swinhoe) (Lepidoptera: Crambidae)

Thirty four maize genotypes were evaluated for resistance to stem borer Chilo partellus (Swinhoe) under artificial infestation during Kharif season 2013, using one day old neonate. The leaf injury rating ranged from 1.25 to 7 on a 1–9 rating scale. The highly resistant germplasms (< 2.0 score) included VIM308, VIM313, VIM19 and VIM 322. While the VIM305, VIM321, VIM325 and VIM 329 along with resistant check were found resistant with damage ranged from 2.25 to 3. The maize inbred lines VIM 280, VIM 283, VIM 301, VIM311, VIM323, and VIM327 were found susceptible (score from 5.10 to 5.75) and remaining genotypes were found moderately resistant. Significant variations were observed in number of leaves per plant, plant height, internodes distance, leaf length, leaf width, leaf trichomes and 100 grains weight. All these characters had negative correlation with the stem borer infestation except number of leaves per plant and stem diameter which had positive correlation. This study reveals that the new resistant landraces give additional sources of resistance and can be useful in future breeding efforts to deliver stem borer resistance into adapted varieties and hybrids where stem borer is a major constraint for maize production.