Yield loss due to the stemborer Chilo partellus (Swinhoe) (Lepidoptera: Crambidae) at different nitrogen application rates to maize

Abstract

Field trials were conducted at Kibaha and Morogoro in eastern Tanzania during two seasons to evaluate the effect of nitrogen fertilization (0, 50, 75, 100 kg [N]/ha) on pest abundance, plant damage and yield loss of maize due to stemborers. In general, ear and grain weights increased linearly with nitrogen level. In the infested plot, grain weight increased 2.5 and 1.8 fold from 0 to 100 kg [N]/ha in the short and long rainy season, respectively, at Kibaha, and 1.4 and 1.6 times at Morogoro. Yield loss decreased with an increase in nitrogen application and the effect was stronger under high than low borer infestation levels. The results show the benefi cial effect of nitrogen on the plant’s ability to compensate for borer damage. Analysis of economic benefi ts of applying fertilizer and insecticide treatment indicated that using insecticides is not profi table under high-pest-low-soil fertility conditions.

Description

International Journal of entomology, 2006; 42(3-4):487-494

Keywords

Stemborer, Chilo partellus, Nitrogen, Yield loss, Swinhoe

Citation