Effect of intercrops on the temporal parasitization of Helicoverpa armigera (Hub.) by larval parasitoid, Campoletis chlorideae Uchida in tomato.

摘要

An experiment was conducted during 2006-07 and 2007-08 to study the impact of seven intercropping system of non-host plants with tomato on the incidence of fruit borer at Dehradun, Uttarakhand. The results indicated that the incidence of fruit borer was found to be minimum when tomato intercropped with coriander, coriandrum sativum, kasuri fenugreek, Trigonella foenum-graecum, barley, Hordeum vulgare; carrot, Daucus carrota; mustard, Brassica compestris and dill, Anethum sowa in 2:1 row ratio. All the intercrops were recorded maximum cocoons of larval parasitoid as compared to sole. Among the intercrops, when coriander associated with tomato attracted maximum cocoons of parasitoid 1.50 and 1.39 cocoons/5 plants followed by kasuri fenugreek 1.06 and 0.94 and mustard 0.89 each during 2006-07 and 2007-08, respectively. The results of pooled analysis showed that coriander was recorded 1.44 cocoons followed by fenugreek 1.00 and mustard 0.89 cocoon/plant, respectively. All the temporal distribution of parasitoid was found insignificant whereas 163 and 156 DAT was recorded maximum cocoons as compared to remaining periods, minimum abundance was recorded in 177 DAT where larval population of H. armigera was escaping because it is follows the incidence of host. The associated crop coriander with tomato recorded 22.57% larval parasitization followed by fenugreek 15.67% and mustard 13.79% as compared to sole crop of tomato 09.09% while 163 and 156 period fell down during month of April during both the year, which recorded maximum 20.80 and 20.43% parasitism activity, respectively.