Effect of organic and inorganic amendments on growth indices and seed yield of red kidney bean (Phaseolus vulgaris) in competition with Amaranthus retroflexus

Abstract

Organic amendments have positive effects on growth indices and seed yield of red bean. They also affect the competition between crops and weeds. In order to investigate the effect of organic and inorganic amendments on the competitive ability of red beans with Amaranthus retroflexus, two experiments were conducted from 2017 to 2018. The experimental design was carried out using a split-plot arrangement with randomized complete block design (RCBD) in three replicates. The treatments included different types of fertilizer and redroot pigweed densities. Fertilizer and weed pressure treatments were determined as sub-plots and main plots, respectively. In a high and low competitive pressure of redroot pigweed, maximum to minimum seed yields were observed when using compost, manure, biochar, nitrogen and no-fertilizer treatments, respectively. Under a high and low competitive pressure of redroot pigweed, maximum to minimum amounts of weed biomass were obtained when using nitrogen, biochar, compost, manure and no-fertilizer treatments, respectively. It can be concluded that weed interference in red bean crop systems can be reduced by using organic amendments as a source of nutrients.