Effects of Seed and NPS Fertilizer Rates on Yield Components and Yield of Bread Wheat (Triticum aestivum L.) in East Badawacho District, Southern Ethiopia

Abstract

Low soil fertility and use of inappropriate seeds rates are among the major constraints limiting the productivity of bread wheat in Ethiopia in general and in the study area in particular. Thus, a field experiment was conducted to assess the effects of rates of seed and sulfur NPS  fertilizer rates on growth, yield components and yield of bread wheat. Factorial combinations of three seed rates (100, 125 and 150 kg ha^-1), and five rates of NPS (0, 50, 100, 150, and 200 kg ha^-1) fertilizer, and blanket recommendation of 100 kg ha^-1 of Di-ammonium phosphate were used for the study. The treatments were laid out in a Randomized Complete Block Design with three replications. The main effect of NPS fertilizers and seed rates significantly (P < 0.01) affected on yield and yield components of bread wheat. The highest spike length (7.77 cm), number of kernels per spike (61.5), and total dry biomass yield (12303 kg ha^-1) recorded at 200 kg NPS ha^-1, while the highest harvest index (0.42) was recorded at 150 kg NPS ha^-1. Similarly, the highest spike length (7.72 cm) and number of kernels per spike (56.85) were obtained at a seed rate of 100 kg ha^-1, while the highest aboveground dry biomass yield (11568 kg ha^-1) and harvest index (0.41) were recorded at seed rate of 150 kg ha^-1. The interaction of seed and fertilizer rates gave significantly the highest number of productive tillers per m2 (413) and the maximum grain yield (6250 kg ha^-1) at the combination of 200 kg NPS ha^-1 with 150 kg seed rate ha^-1. The partial budget analysis showed the highest net return (44878.2 birr ha^-1) with marginal rate of return 97.7% was obtained from a combination of 200 kg NPS ha^-1 with seed rate of 150 kg ha^-1. Thus, it can be concluded that seed rate of 150 kg ha^-1 and 200 kg NPS ha^-1 to be appropriate for bread wheat production in the study area.