INFLUENCE OF NITROGEN FERTILIZATION LEVELS ON GRAIN YIELD AND ITS COMPONENTS IN BARLEY (Hordeum vulgare L.)

Abstract

SUMMARYGrain yield and its components are very important and complicated in barley and highly have been influenced by agronomic applications and environmental factors. On the other hand; this is depend on combination varied plant traits (agronomic and quality). For this season, the study was designed to evaluate the effects of different nitrogen fertilization levels (0, 10, 20, 30 and 40 kg ha -1 of N) on the agronomic performance of five barley cultivars in two growing seasons. Split plot layout within randomized complete block design with 3 replications was used in both years. The response to fertilization levels were evaluated through GGE (Genotype main effects and Genotype x Environment interaction) biplot graphic methodologies and regression. Combined analysis of variance of nitrogen applications of five cultivars showed highly significant (p<0.01) difference between the cultivars, nitrogen applications and interaction. There were genetic variability among cultivars on grain yield and yield components in response to nitrogen fertilization. The results showed that biggest increases on yield and yield components were observed under 40 kg/ha -1 nitrogen fertilization level, while thousand grain weight was the biggest under without nitrogen application. The higher performance of yield and yield components was associated with higher nitrogen fertilization in regression analysis. The results of the this study has been recommended that it should be use and study higher nitrogen application levels than 40 kg ha -1 of N in the next barley studied.

Nitrogen efficiency indexes association with nitrogen recovery, utilization, and use efficiency in spring barley at various nitrogen application rates

“…The increase and reduction in HI might be attributed to the genetic variability of the plant vis-à-vis the N application rate, which affects the proportional increase of grain and biomass yields. Oral et al demonstrated that BY and HI are more dependent on genotype than on seasonal variability (Oral et al, 2018). The HI has also been reported as dependent on the grain/biomass ratio, which ultimately depends on genetic availability and nutrient uptake, especially of N. A higher amount of N results in a greater aboveground biomass up to a certain rate, but any increase above this level can reduce yield and HI (Uhart & Andrade, 1995).…”

“…For instance, the lowest GY was 2,000.7 kg ha −1 at 60 kg N ha −1 , and the highest GY was 8,607.9 kg ha −1 at 120 kg N ha −1 ; however, the maximum BY was recorded at 180 kg N ha −1 (Gursoy, 2011; Hadi et al., 2012; Pampana et al., 2021). These data could be attributed to the greater dependency of the biomass yield of the cultivars is on genotype inheritance and weather conditions, so GY increased gradually with the increase in N level in the soil until a certain level was reached, and the continuous increase in the N application rate led to an increase in straw yield rather than GY (Oral et al., 2018; Shah et al., 2003). Several studies have demonstrated that the best yields were achieved with 70–120 kg N ha −1 (Mandic et al., 2015; Teixeira Filho et al., 2010).…”

The combined effect of nitrogen fertilizer and sowing season on response to water-limited stress in barley (Hordeum vulgareL.)

“…Oral et al . (2018), for instance, in their study on barley cultivars, reported that the increased nitrogen application had positive effects on the GY and yield components by increasing the vegetative growth and photosynthesis. On the other hand, the high use of nitrogen fertilizer in barley can lead to inappropriate vegetative growth, more lodging, low grain weight, lower number of spikes, delayed maturity, and more susceptibility to pests and diseases under normal irrigation conditions (Alam et al ., 2007).…”