Seed priming SEAGRO liquid fertilizer most efficacious mode eliciting growth and accumulation of nutrients in shoots and rhizosphere soil of three-week-old cowpea (Vigna unguiculata L. Walp) cultivars planted in a potted experiment

Abstract SEAGRO is a liquid fertilizer sold across South Africa and is not recommended for co-addition with other fertilizers. It is recommended for addition through drenching or foliar application on fruit trees and vegetables, among other plants. Cowpea is a leafy vegetable that is native to southern Africa and is cultivated for use as food, feed, medicine, and soil improver. So far, there exist no published information on whether adding SEAGRO liquid fertilizer to food crops that are widely cultivated in South Africa improve the growth, yield, and quality. This study assessed effects of adding SEAGRO liquid fertilizer through different modes on the growth, mineral nutrient accumulation in shoots as well as rhizosphere of cowpea cultivars. The experiment used topsoil collected from the Bon Accord Farm, air-dried, sieved, and 7 kg added into experimental plastic pots. Factors of the experiment involved: mode of SEAGRO application (control: no addition of SEAGRO), seed priming, drenching, seed priming plus drenching, foliar application, drenching plus foliar application, seed priming plus drenching plus foliar application); and cultivar (IT-18 and Accession 791). Each treatment was replicated three times. A solution of SEAGRO was prepared through mixing 5 ml of concentrated SEAGRO with 1 L tap water. Results of this research revealed that three-week-old cowpea plants of the IT-18 cultivar had significantly greater fresh and dry root weights. Also, priming seeds was the most efficacious of the modes of adding SEAGRO to the three-week-old cowpea cultivars. Accession 791 had greater shoot P, Mg, and Fe. Drenching and/or seed priming using SEAGRO improved shoot P and Mg while drenching plus foliar application increased shoot K. The concentration of Fe, Zn, and B was increased by the priming and/or drenching modes. The concentration of K and Fe was increased in the rhizosphere of the cowpea cultivars.