A Short Season Canadian Soybean Cultivar Double Cropped After Winter Wheat in Uzbekistan With and Without Inoculation with Bradyrhizobium

M Bourgault,C A Madramootoo,H A Webber,D L Smith,G Stulina,M G Horst

doi:10.5539/jps.v4n2p74

Abstract

Agricultural systems in Uzbekistan are dominated by the production of cotton and winter wheat as these crops are subject to state-prescribed quotas. An experiment was conducted in the Fergana valley, in Uzbekistan, Central Asia, to determine the feasibility of growing a short-season Canadian soybean ( Glycine max [L.] Merr.) cultivar after the harvest of winter wheat in early July. An inoculated treatment was compared to a non-inoculated control in a randomized complete block design with four blocks. While the inoculation did not establish well in 2003, in 2004, the yield of inoculated soybean was twice that of the non-inoculated control (106% increase). Inoculation in 2004 increased seed weights by 30%, final pod number by 29%, biomass dry weight at the pod-filling stage (56%) and at harvest (56%), as well as the harvest index by 22%. Nodules were, in general, only present in the inoculated treatments, which indicated that appropriate indigenous rhizobial strains were not present in these soils, but ineffective rhizobial competitors to commercial inoculants were also absent. Soybean production could be possible in Uzbekistan without competing with state prescribed crops such as cotton and winter wheat. Based on prices from 2004, this represents an additional income of more than 300$ ha -1 . More research is needed to determine the optimal conditions for inoculation success in hot and dry climates.

Highlights

Agricultural policies in Uzbekistan emphasize the culture of cotton, an important component of the Uzbek economy, and to a lesser degree, winter wheat
More research is needed to determine the optimal conditions for inoculation success in hot and dry climates
A soybean crop was grown to maturity using a short-season Canadian variety after the harvest of winter wheat in the Fergana valley, in Uzbekistan, Central Asia

Summary

Introduction

Agricultural policies in Uzbekistan emphasize the culture of cotton, an important component of the Uzbek economy, and to a lesser degree, winter wheat. Both are subject to state regulation through a system of quotas, and little agricultural land is left for other crops. A typical rotation starts with cotton being planted in April, and harvested from September to December. Winter wheat is planted in November to December, in between rows of cotton, and harvested late June to mid-July in the following year. To improve land productivity and food security in the region, the introduction of food legumes as double crops after the harvest of winter wheat was previously suggested (Bourgault et al, 2013). Legumes in rotation with other crops can break disease cycles, improve the fertility and structure of the soil and encourage the development of mycorrhizal associations (Subbarao et al, 1995)

Methods

Results

Conclusion