EFFECT OF GENOTYPE AND SOWING DATE ON THE RESPONSE TO BORON IN WHEAT

Abstract

A field trial was conducted in an alluvial soil of8angladesh to evaluate the effect of boron on the number of grains/
spike, grain yield and nitrogen content of wheat sown in different dates. The experiment comprised two 8 treatments
(0 and 3 kg 8/ha), three wheat varieties (Sonalika, Kanchan and Aghrani) and four dates of sowing with 2-week intervals
beginning from the November 15 of 1992. The experiment was laid out in split-split plot-design with sowing date
as main-plot, wheat variety as sub-plot and boron treatment as sub-sub-plot. The results showed that added 8 had
positive efffect on the number of grains/spike and grain yield. Both grains/spike and grain yield were decreased as the
date of sowing was delayed particularly after December I, over the varieties. Among the varieties, Kanchan gave
comparatively better yield. Nutrient analysis showed that Nand 8 contents in grain were increased after B treatment
to soil indicating that 8 probably helped protein synthesis. Like grain yield, grain N level had declined with the delaying
of sowing date. Such adverse effect of late sowing was thought to be related with elevated temperature prevailing at
flowering stage that induced slower rate of B mobility in plant, poor number of grains/spike and lower grain yield.