PERFORMANCE OF SOYBEAN (Glycine max (L.) Merr.) VARIETIES AS INFLUENCED BY SOWING METHODS AND WEED CONTROL TREATMENTS IN THE NIGERIAN SAVANNA

PERFORMANCE OF SOYBEAN (Glycine max (L.) Merr.) VARIETIES AS INFLUENCED BY SOWING METHODS AND WEED CONTROL TREATMENTS IN THE NIGERIAN SAVANNA

Abstract:

A field trial was conducted during the wet season of 2016 at two locations, one at Samaru (11o11’N, 7o 38’E 686 meters above sea level) in the Northern Guinea savannah and the other at Bagauda (11’37N, 8 o 23’E, 500 meter above sea level) in the Sudan savannah of Nigeria, to study the performance of two soybean varieties as influenced by sowing method and weed control treatments. The experiment consisted of two varieties of soybean, (TGX 1448-2E and TGX 1987-10F), two sowing methods (Dibbling and drilling) and four weed control treatments.( Pendimethalin at 2.0 kg a.i. kg/ha applied as pre-emergence, fusillade 2.0 kg a.i. /ha applied as post emergence, hoe weeding at 3, 6 and 9 WAS and weedy check). The treatments were laid out in a split plot design with factorial combinations of weed control treatments and sowing method assigned to the main plot, while variety was assigned to the sub-plot. The results showed that variety TGX 1448-2E recorded lower weed dry weight and produced taller and more vigorous crops that had wider canopy and higher grain yield at both locations than TGX 1987-10F. Drilling method of sowing recorded lower weed dry weight, weed cover score, and produced more vigorous crop plants with wider canopy cover, higher total dry weight than the dibbling method of sowing. The weedy check plots recorded significantly higher weed dry weight, weed cover score and weed density than all the other weed control treatments. The treatments with fluazifop-butyl (fusillade) at 2.0 kg a.i.kg/ha resulted in significantly taller plants with wider canopy cover and more vigorous crops than Pendimethalin at the same rate. On the other hand, hoe weeding at 3, 6, and 9 WAS recorded higher seed yields than other weed control treatments. There was a positive and significant correlation among all the growth parameter and yield in both locations. While the correlation among weed parameters and yields are significant and negative. Shoot dry weight and haulm yield made the highest individual positive contribution of 38.7% and 20.4% to yield in both locations. Economic analysis of soybean production at both locations showed that variety TGX 1448-2E; drilling method of sowing and the application of fluazifop-butyl (fusillade) at 2.0 kg a.i.kg/ha gave the highest gross margin of N152098.00/ha and N124013.00/ha as well as gross margin per naira invested at Samaru and Bagauda respectively. Base on the results obtained from this study, it can be concluded that hoe weeding at 3, 6 and 9 WAS, fluazifop-butyl applied as post emergence at 2.0 kg a.i./ha and drilling method of sowing resulted in effective weed control and recorded the highest grain yield in both location. Variety TGX 1448-2E performed better than variety TGX 1987-10F during the trial.

PERFORMANCE OF SOYBEAN (Glycine max (L.) Merr.) VARIETIES AS INFLUENCED BY SOWING METHODS AND WEED CONTROL TREATMENTS IN THE NIGERIAN SAVANNA