Evaluation of the Effect of Arbuscular Mycorrhizal Fungi on the Root and Shoot Growth of Some Cowpea Varieties (Vigna Unguiculata (L.) Walp) UnderAlectra Vogelii Inoculation

Abstract

The aim of this research was to evaluate the effect of Glomus clarum on the root and shoot fresh weight of four cowpea varieties on Alectra vogelii inoculated soil. Four cowpea varieties used were: SAMPEA 7, IFE 82-12, IT97K-499-35 and TVX 3236. The sterilized sandy-loam soil used for this experiment consisted of a mixture of topsoil and sand in ratio 1:1 (v/v). Glomus clarum was applied in five rates: the control without Alectra, control with Alectra, 10, 20 and 30 g/pot. A constant quantity of Alectra was maintained. The treatments were arranged in complete randomized design. Four cowpea seeds were planted per pot but later thinned to two seedlings per pot at two weeks after planting (WAP). These cowpea plants were sampled for root and shoot fresh weight at 5, 7 and 9 WAP. The ANOVA of the three years’ data showed that Glomus clarum treatments at different rates significantly increased root and shoot fresh weights compared with the two control treatments. Glomus clarum treatment at 30 g/pot resulted in the highest root and shoot fresh weight of the cowpea varieties Cowpea variety SAMPEA 7 mostly resulted in the higher values compared with other cowpea varieties for root and shoot fresh weight at 9 and 7 WAP respectively. From this study, Glomus clarum treatments significantly increased root and shoot fresh weight of the four cowpea varieties. Therefore, in relation to root and shoot fresh weight of the four cowpea varieties, Glomus clarum is recommended as a biological control agent on an Alectra vogelii infested soil.