Effect of saline irrigation water on yield and yield components of rice (<i>Oryza sativa</i> L.)

Abstract

Salinity is an agricultural problem which decreases or restricts crop production worldwide. Saline water can be used in crop production if the yield reduction can be ameliorated. For this purpose, a greenhouse experiment was conducted in Rasht, North of Iran to assess the effects of water salinity levels at different growth stages of rice on yield and its components. Treatments included four levels of saline water (2, 4, 6 and 8 dS m^‒1) and four growth stages (tillering, panicle initiation, panicle emergence and ripening) in a completely randomized block design. The results indicate that increased salinity significantly deceased grain yield, number of filled panicles, biomass and harvest index but effect of salinity on straw weight, 1000-grain weight, number of tillers and plant height was not significant. Increasing salinity decreased grain yield so that more increase in salinity showed more effect on yield decrease. The most grain yield, that is, 23.59 g/pot, was seen at control treatment irrigated by fresh water (at 1 dS m⁻¹ salinity) and the least grain yield, that is, 12.59 g/pot, obtained at 8 dS m⁻¹ salinity. Effect of different growth stages on all yield components except number of tillers was significant. Different growth stages showed different sensitivity to salinity. In fact, the primitive growth stages, that is, tillering and panicle initiation showed more sensitivity to salinity than final growth stages (panicle emergence and ripening). Therefore, irrigation with saline water at the early growth stages has more negative effect on yield and its components.

Keywords: Yield, biomass, growth stages, saline soil, salt stress, water salinity.

African Journal of Biotechnology Vol. 12(22), pp. 3503-3513