z s; m d; mehdi panahi; E A
Abstract
Effects of six irrigation treatments on vegetative characteristics, yield, and sugar content of sugar beet and water use efficiency were investigated. The experiment was conducted at Aleshtar in Lorestan province during growing seasons of 2014 and 2015, using a randomized complete block design. Irrigation ...
Read More
Effects of six irrigation treatments on vegetative characteristics, yield, and sugar content of sugar beet and water use efficiency were investigated. The experiment was conducted at Aleshtar in Lorestan province during growing seasons of 2014 and 2015, using a randomized complete block design. Irrigation treatments consisted of full irrigation (T1) as the control, T1 +cutting off the last irrigation (T2), 10% higher than the control (T3), 10% less than the control (T4), 20% (T5) and 30% less than the control (T6). The results of combined analysis of variance showed that the effects of different irrigation treatments on leaf area index, tuber dry weight, root yield, biomass, sugar content, sugar yield and water use efficiency on the basis of sugar yield was significant at 1% level. However, their effects on leaf dry weight and water use efficiency on the root yield basis was significant at 5% level. Although there were no significant differences between T2, T3, and T4 treatments in terms of crop vegetative characteristics, root yield, biomass and sugar yield, they increased these characteristics significantly compared to T5 and T6 treatments. Also, the highest water use efficiency on the basis of both root and sugar yield was obtained in T2 and T4 treatments. Therefore, to conserve water in sugar beet production in Lorestan province, decreasing the amount of water up to 10 % at each irrigation during the growing season or cutting off the last irrigation is recommended.
Z SAADATI; NADER PIRMORADIAN; E AMIRI; M REZARI
Abstract
In order to increase water productivity, a good understanding of crop response to water stress and tools which simplify the complex crop response to various environmental factors, especially to water, are needed.Simulation models that clarify the effects of water on crop yield are useful tools for improving ...
Read More
In order to increase water productivity, a good understanding of crop response to water stress and tools which simplify the complex crop response to various environmental factors, especially to water, are needed.Simulation models that clarify the effects of water on crop yield are useful tools for improving farm level water management and optimizing water productivity. In this study, the WOFOST model was used to simulate two local rice varieties yield response under five irrigation treatments consisting of continuous flooding and irrigation at 0, 3, 6 and 9 days after disappearance of water from the soil surface. The experiment was conducted at Rasht region during two growing seasons of 2003 and 2004. The model was calibrated using the first year data and was validated using the second year data set. According to the results, the relative root mean square errors of grain yield simulation were 12.57% and 5.01% for Binam and Hasani cultivars in 2003, respectively. These values were 7.94% and 13.71% in 2004, respectively. The values of the observed and simulated water productivity based on precipitation and consumed water were close together. The results showed that the WOFOST model could simulate the effect of water on rice yield and water productivity in a humid region. Therefore, this model can be used to explore optimum management options to improve rice water productivity.