Infestation of insect pests in tree-rice agroforestry system

The prevalence of insect pests was studied on rice BR11 (mukta) as understory crop grown in association with 11 years old selected tree species viz, Akashmoni, Jhau and Albida in the field laboratory of the Department of Agroforestry, Bangladesh Agricultural University (BAU), Mymensingh during the period from July to December, 2003. Among the three species Albida and Jhau possessed the largest canopy and there light penetration rate were high. On the other hand, Akashmoni had the lowest canopy but it penetrated low amount of light. Albida-rice association showed the lowest infestation of major rice insects followed by Jhau-rice association, while Akashmoni-rice association showed the highest insect infestation. Light intensity in the control plot (absent of tree species) was maximum and it caused minimum severity of insects infestation as compared to other associations. From the result it appeared that light interception has the relationship with insect population in rice. Therefore, tree species having sparse canopy which allowed easy penetration of sunlight is suitable for tree-rice agroforestry system.