Influence of environment on protein and oil contents of soybeans seed (Glycine Max (L.) Merril)

Abstract

An attempt was made to study the magnitude of environmental variability on protein and oil contents of six genetically diverse soybean genotypes under three environments represented by three locations in Nigeria (Zaria in Northern Guinea Savanna, Jos in Pseudo Savanna and Mokwa in Southern Savanna) for two years (1996 and 1997). Significant genotypic location and location x genotype x year effects were observed for protein content while genotypic and location x genotype effects were significant for oil contents. Significant genetic differences in protein content occurred among genotypes, locations and between years, whereas significant genotypic differences in oil content was observed. Bossier and TGX849-313D out yielded in protein content. Protein content in Mokwa and Zaria were higher than that of Jos while protein content in Year 2 (1997) was higher than Year 1 (1996). Oil content remained similar irrespective of location and year. Jos is in a dry cool environment compared with Mokwa which is humid and hot and Zaria which is dry and hot. Environmental factors exerted greater influence more on the protein content than oil content of tropical soybean seeds. High temperature tended to increase protein content with little or no effect on oil content. There was positive significant association between protein and oil contents under Jos environment in 1997 whereas the association was negatively significant under Mokwa environment. Therefore, selection for protein and oil contents among soybean genotypes for further improvement is possible due to large variability present. Variations in protein and oil contents were due to differences in location. Changes in climatic factors resulting from yearly cultivation of soybean in different locations can influence protein content. Key Words: correlation analysis, genotype, Glycine max, oil, protein [Global Jnl Agric Sci Vol.1(1) 2002: 27-32]