Disease management factors influencing yield and quality of sorghum and groundnut crop residues

Abstract

Crop residues from groundnut and sorghum constitute important fodder resources for dairy production and fodder trading on the Deccan Plateau in India. This paper addresses the effect of important diseases of groundnut and sorghum on pod and grain yield and crop residue yield and quality. In four genotypes of groundnut, late leaf spot (Phaeoisasariopsis personata) and rust (Puccinia arachidis) are the two major foliar diseases that together could reduce pod and haulm yield by 70% and in vitro digestibility of haulms by 22%. Two genotypes (ICGV 9202 and 92093) were highly resistant to these foliar diseases maintaining high pod and haulm yield as well as high in vitro digestibility of haulms (>62.3%) even under highest disease pressure. Important diseases in sorghum investigated were a viral disease caused by maize stripe virus (MStV) and anthracnose caused by Colletotrichum graminicola. MStV reduced grain yield by 30%, stover yield by 42% and digestible stover yield by 45%. Effects of MStV were highly genotype-dependent and grain and stover were affected in different ways in different varieties. The choice of appropriate genotype for a given farming situation will depend on trade-off scenarios for benefits from grain and stover. Similarly, anthracnose could reduce grain yield by 47% and stover yield by 23% but effects on stover quality were variable. As observed for MStV, effects of anthracnose were highly genotype-dependent and genotypes were identified that maintained high grain and stover yield under high disease pressure