Yield and yield components of safflower as influenced by genotype and plant density grown in the semi-arid conditions of Botswana

Abstract

Two field experiments were carried out at the Botswana University of Agriculture and Natural Resources in Southern Region of Botswana to evaluate the effects of plant density and genotypes on yield and yield components of safflower. The treatments were five safflower genotypes (Kiama composite (local), Sina-PI 537598, Gila -PI 537 692, PI 537 636 and PI 527 710 and plant density (62,500, 83,333, 100,000, 125,000, 166,666 and 200,000). Increase in plant density from 62,500 to 100,000 plants/ha significantly (p < 0.0001) increased vegetative growth, yield components and seed yield of safflower. As plant density increased above 100,000 plants/ha vegetative growth, yield and yield components significantly (p < 0.0001) decreased in all genotypes both in winter or summer grown safflower. It was concluded that there is variation in the performance of safflower genotypes in response to increasing plant density and growing season, but optimum plant density to maximize safflower seed yield under Botswana conditions was 100,000 plants/ha (Botswana is 40 cm x 25 cm).