Soybean Varietal Evaluation and Selection in Mozambique.

Recent growth in the poultry and livestock industry in Mozambique has created substantial demand for soybean meal for feed. The demand for soybean grain is estimated at 40,000 tons/year. Despite this demand, total production nationwide is approximately 5,000 tons/year due in part to limited access to improved varieties and information on better crop and soil management practices. The major objectives of this study are to identify high-yielding soybean genotypes adapted to the various agro-ecological zones of Mozambique and to determine the optimum planting date for the selected genotypes. Field experiments were conducted on clay loam soils at several locations in 2007-2009 using several genotypes developed in Nigeria by IITA. For the planting date trials, seeds were planted at various locations on four different dates at 14-day intervals beginning in December. Fifteen promising genotypes were selected from more than 300 genotypes screened for further evaluation. The growing period for all genotypes is longer than that observed in Nigeria due to the relatively low temperatures in Mozambique. Some genotypes did not complete seed-filling when planted after the second week of January. In addition, the plants were bigger and taller, and also produced more foliage at sites with cool and high rainfall. Yields consistently decreased across locations when planting delayed. For example, yields in 2008 for the site with relatively high rainfall on average ranged from 1600-4400 kg/ha when planted in the last week of December compared with 500-1600kg/ha for those planted in the second week of February. The relatively early-maturing genotypes (TGx 1740-2F and TGx 1485-1D) among the population evaluated fit better into the cropping systems of all agro-ecologies than the late-maturing genotypes. The data indicate that for all locations, early planting between the first and third week of December is the best time to plant soybean. Five of the promising genotypes are being considered for variety release.