Response of agronomic and physiological indices of Iranian rice cultivars to integrated NPK fertilizers application
Subject Areas : Crop Production Research
Hasan Jafari
1
,
حسین عجم نوروزی
2
,
MohammadReza Dadashi
3
,
Afshin Soltani
4
1 - PhD Student, Department of Agronomy, Gorgan Branch, Islamic Azad University, Gorgan, Iran.
2 - Associate Professor, Department of Agronomy, Gorgan Branch, Islamic Azad University, Gorgan, Iran.
3 - Assistant Professor, Department of Agronomy, Gorgan Branch, Islamic Azad University, Gorgan, Iran.
4 - Prof, Department of Agronomy, Gorgan University of Agricultural Science and Natural Resources, Gorgan, Iran.
Keywords: Grain yield, Lodging index, NPK uptake, Rice,
Abstract :
The aim of present study was to investigate the effects of NPK chemical fertilizer management on parameters related to lodging, yield components, grain yield and NPK nutrient uptake in local rice cultivars. The experiment was conducted in farms located in Mazandaran province, Sari, during 2017 and 2018. The experiment was performed as split plot in a randomized complete block design with four replications. The different doses of fertilizer treatments at five levels including F1: N250P150K150, F2: N200P100K100, F3: N150P75K75, F4: N100P50K50, and F5: Control (N0P0K0) as main plot and local rice cultivars at two levels of Sang Tarom and Tarom Hashemi were considered as sub-plots. The results showed that the highest third and fourth internodes lodging index were observed in N250P150K150 and N200P100K100 treatments. Application of N200P100K100 treatment increased the number of fertile tillers per hill (13.25) and finally produced highest grain yield (4806 kg/ha-1), although there was no significant difference with N250P150K150 and N150P75K75 treatments. When the doses of NPK fertilizers increased, the concentration of NPK in grain and straw and as well as grain protein content also enhanced. There was no statistically significant difference between the two cultivars in terms of grain yield and concentration of N and K in plant, but the concentration of P in grain for Tarom Hashemi cultivar was about 8.9% higher than Sang Tarom. According to the findings of this study, the application of N150P75K75 treatment is a better option to improving the grain yield of rice cultivars along with a decrease in chemical fertilizers and subsequent reduced fertilizers costs and environmental damages.