Resistance in maize to Chilo partellus (Swinhoe) (Lepidoptera: Pyralidae): role of stalk damage parameters and biological control
1997
Kumar, H.
The objective of the present study was to elucidate the relationship among certain damage parameters measured under natural and an artificial infestation of four maize genotypes by Chilo partellus (Swinhoe) (Lepidoptera; Pyralidae). The maize genotypes used were Inbred A, MBR 8637, MMV 400 and PR 7832. Artificial infestation was done at the 6-leaf stage and flowering stages with egg masses at black-head stage. For natural infestation, genotypes were grown under the prevailing natural population of C. partellus. At harvest, data were recorded on individual plants. A highly significant correlation was observed between number of holes and stem tunneling (expressed as the absolute tunnel length or the percentage of stem length tunneled) by C. partellus on four maize genotypes. The relationships between the parameters varied with genotype and plant phenological stages at infestation. Damage by C. partellus to grain and stem was not consistently correlated among genotypes and phenological stages at infestation. These results indicate that number of holes can be used in place of the laborious method of splitting stalks for determining resistance in maize against C. partellus. The solitary parasitoid Dentichasmias busseolae Heire, was found to parasitize C. partellus pupae. Parasitization was highest on PR 7832 (50-57%) followed by Inbred A (40%), MMV 400(37%) and MBR 8637(29%). Thus, PR 7832 would serve as an ideal genotype for an integrated pest management of C. partellus involving host plant resistance and biological control.
显示更多 [+] 显示较少 [-]