RESPONSE OF SOYBEAN GENOTYPES TO BORON, ZINC AND MANGANESE DEFICIENCYIN TISSUE-CULTURE

The effect of boron (B), zinc (Zn), and manganese (Mn) deficiency in t he medium on eight soybean genotypes was evaluated using friable callu s after a 21 day growth period. Of the three micronutrients evaluated, Zn and B deficiencies had the greatest effect on callus weight, while Mn had only a slight effect. Despite this, significant differences in callus weight reduction of the eight genotypes tested were observed o n the three different media. These results indicate that genotypic var iation for response to B, Zn, and Mn deficiency is present in soybean at the cellular level. If the resistant genotypes identified in this s tudy are also resistant at the whole plant level, then they could be u sed in soils which are deficient in the above micronutrients.