majid moslemi; hamidreza mobasser; nematollah sedaghat; eiman eshghi
Abstract
Optimizing the rate of nitrogen fertilizer application is one of the important management strategies for yield improvement. In order to investigate the effects of nitrogen levels & stress during two years on morphological characteristics & agronomic traits of rice, an experiment was conducted ...
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Optimizing the rate of nitrogen fertilizer application is one of the important management strategies for yield improvement. In order to investigate the effects of nitrogen levels & stress during two years on morphological characteristics & agronomic traits of rice, an experiment was conducted in the form of split plots in a randomized complete block design with four replications in 2009 & 2010 in a research farm located in Amol. Nitrogen levels at three levels (46, 69, 92 kg N / ha from urea source) as the main factor & sub-factor including four levels of stress or lack of nitrogen consumption (T1 = stress at full clustering stage, T2 = stress at stage the emergence of the initial cluster was T3 = stress at tillering stage and T4 = stress at transplanting stage). The results showed that number of full panicles per panicle, 1000-seed weight, Grain yield and harvest index in 2009 it was more than in 2010. Grain yield in the first year (450.25 g / m2) was higher than the second year (395.1 g / m2). Maximum harvest index was obtained in 2009 with nitrogen stress at full clustering stage. Therefore, the application of 69 kg of nitrogen in installments per hectare can be suggested to produce the highest grain yield.