Effect of different levels of <i>Striga gesnerioides</i> on the growth and yield of some local and improved cowpea (<i>Vigna unguiculata</i> (L) Walp) varieties

Abstract

Experiment was carried out at International Institute for Tropical Agriculture (IITA), Kano, Nigeria. The aim of the study was to evaluate the effect of different levels of Striga infestation on the growth and yield of some varieties of cowpea. Four cowpea genotypes were selected for the study. The experiment was laid out in randomized complete block design with two treatment regimes of Striga infestation. The levels of Striga infestation include 0.05g, 0.1g and 0.0g (control). The results showed that IT97K-499-35 recorded higher plant height at 0.5g and 0.1g of Striga infestation, but DANILA showed lower plant height at 0.1g of Striga infestation. The result for chlorophyll content (SPAD) indicates that at 30 days after Striga infestation, IT99K-241-2 recorded higher chlorophyll SPAD value of 39.2. But IT97K-499-35 had lower chlorophyll SPAD value of 16.3. Higher number of days to 50% flowering was recorded in IT99K-241-2 across the treatment. IT98K-205-8 recorded early days to 50% flowering across the treatment. IT99K-241-2 and DANILA recorded Striga emergence and attachment to their roots. But IT97K-499-35 and IT98K-205-8 had no Striga attachment and emerged. Higher grain yield was recorded in IT97K-499-35, but IT99K-241-2 and DANILA recorded lower grain yield. Higher Fodder yield was recorded in DANILA. The result indicates that fodder yield was reduced in 0.5g and 0.1g of Striga infestation in all the varieties. The present study conclude that varieties IT99K-241- 2 and DANILA were susceptible to Striga at 0.1g of infestation, while IT97K-499-35 was tolerant to Striga at 0.5 and 0.1g of Striga infestation.

Keyword: Striga gesnerioides, Cowpea, growth and Yield