Growth, grain yield, and water productivity of traditional rice landraces from coastal Bangladesh, as affected by salt stress

Abstract

Salinity is a major abiotic stress limiting the growth, development, and productivity of rice (Oryza sativa L.) worldwide. A 10 × 4 factorial pot experiment consisting of 10 traditional aus rice (summer rice) landraces (Noyontara, Ratul, Rani Ratul, Sribalen, Mala, Kolmilata, Nayanmoni, Noncha, Kopilaice, and Kajollata) and four levels of water salinity (0.36 [control], 5, 10, and 15 dS m−1) was conducted to evaluate the salt tolerance of the popular traditional rice landraces. The results revealed that plant height, shoot dry matter, soil plant analysis development (SPAD) value, panicle number plant−1, filled-grain percentage, 1000-grain weight, grain yield, harvest index, and irrigation-water productivity were significantly affected by water salinity. The highest shoot dry matter, grain yield, and irrigation-water productivity were recorded for Noncha at the highest salinity level of 15 dS m−1, indicating its high salinity-tolerance ability. The 15 dS m−1 salinity level reduced shoot dry matter and grain yield of Kopilaice by 61% and 75%, respectively, relative to Noncha. The tested cultivars could be classified into three categories: (i) salt sensitive that cannot withstand salinity level above 5 dS m−1: Kopilaice, Noyontara, Ratul, Rani Ratul, and Sribalen, (ii) intermediate-salt tolerant that can withstand salinity below 10 dS m−1: Mala and Nayanmoni, and (iii) highly salt tolerant that can withstand salinity up to 15 dS m−1: Noncha, Kolmilata, and Kajollata. Noncha, Kolmilata, and Kajollata were considered promising salt-tolerant cultivars and can be used as valuable genetic resources for developing salinity-tolerant cultivars in the coastal salinity-affected region of Bangladesh.