Effect of intermittent irrigation with saline water on rice yield in Rasht, Iran / Učinek periodičnega namakanja s slano vodo na pridelek riža v provinci guilan, Rasht, Iran

Abstract

Guilan, a well-known province in rice production in Iran, has been facing water shortage and water degradation. In order to study the effects of salinity stress as well as water stress on rice a pot experiment was conducted at Rice Research Institute of Iran. Five water salinity levels: fresh water (EC = 1 dS m -1 ), 2, 4, 6 and 8 dS m -1 and five irrigation regimes: continues flooding, Alternative Wetting and Drying (AWD), intermittent irrigation at 100, 90 and 80 percent of field capacity (FC) were considered as irrigation treatments. The results showed severe effects of water and salinity stresses on rice yield and yield components. Fresh water produced the highest yield, 18.57 gr pot -1 , whereas, the yield in salinity levels of 2, 4, 6 and 8 dS m -1 were 13.78, 5.78, 3.61 and 0.74 gr pot -1 , respectively, with the yield losses of 25, 70, 80 and 97%, respectively. Intermittent irrigation at FC produced the highest yield. The yield increased 8 and 13% in AWD and intermittent irrigation at FC treatments respectively, while it decreased 8 and 27% in intermittent irrigation at 80 and 90% of FC treatments as compared with continues flooding treatment. The highest yield with application of intermittent irrigation at FC was valid only in water salinity less than 4 dS m -1 . When water salinity was higher than 4 dS m -1 all irrigation methods gave the same yield. This study showed that the best method to use saline water was intermittent irrigation at FC with EC = 2 dS m -1 . In case of more salinity, mixing fresh and saline water and intermittent irrigation can mitigate the severe effects of salinity on rice. . Če je bila slanost vode večja, so dali vsi postopki namakanja enak pridelek. Raziskava je pokazala, da je najboljši način periodičnega namakanja s slano vodo pri poljski kapacite s prevodnostjo vode za namakanje 2 dS m -1 . V primeru večje slanosti je potrebno izmenično namakati s sladko in slano vodo, da se izognemu velikemu učinku slanosti na pridelek riža.Ključne besede: riž, namakanje, slana voda, Iran M. REZAEI et al.

Coupled Irrigation–Drainage Management Practice for HYV Rice Cultivation with Saline-Irrigation Water: Evidence from Lysimeter Experiment

“…Where available, irrigation with good quality water prior to sowing helps leaching the salts from the top soil. Mixing fresh water and saline water, and intermittent irrigation can also mitigate the detrimental effects of salinity on rice (Rezaei et al, 2013). But, in the absence of fresh water, removing the saline water from the rice field at certain interval to keep water salinity at non-harmful level may be an important practice to develop an effective on-farm water management for rice cultivation on saline soils (Chen et al, 2013).…”

Simulation of rice yield under different irrigation and nitrogen application managements by CropSyst model

“…Recently, the decrease of fresh water resources has made a great concern on rice production in Guilan province. Climate changes, degrading of water resources and continuous drought has influenced agriculture in general and farmers' incomes specifically (Rezaei et al 2013). Besides, local varieties of Iran are resistant to intermittent irrigation conditions (Razavipour et al, 2000).…”