Impact of different water management and microbe application on yield of rice cultivars under seawater intrusion areas of Indonesia

Primary risk to rice (Oryza sativa L.) production is salinity intrusion and water scarcity, leading to a shortage of irrigation water and yield reduction. We examine the impact’s effects of alternate wetting and drying (AWD) vs. continuous flooding (CF) and microbe application on yields of three rice cultivars (Ciherang, Inpari 34 Salin Agritan, Inpari 35 Salin Agritan) grown under slight and moderate soil salinity in the dry season (DS) 2017 and 2018. Under slight soil salinity, AWD and CF had nonsignificant difference in grain yield. Under a moderate soil salinity level, there was a substantial decrease in grain yield (8.2%), number of productive tillers, seeds panicle-1, and weight of 1000 grains with the plants grown under AWD. Increased soil salinity levels resulted in lower yield reduction with microbial than without microbial treatments. ‘Ciherang’ showed superiority over ‘Inpari 34’ and ‘Inpari 35’ under AWD at slight soil salinity. However, the yield reduction in the moderate salinity level was more remarkable for ‘Ciherang’ (18.1%) than ‘Inpari 34’ and ‘Inpari 35’ (9.7%) as salinity-tolerant varieties. The AWD used almost one-third less irrigation supplement than CF. This greatly assists small farmers in reducing the additional cost of pumping water. On average, AWD improved total water productivity by 32.7% under slight and 20.4% under moderate soil salinity over CF. Here, we lay out the potential for small farmers in slight salinity lowlands areas of the northern coast of Java to apply AWD during the DS. Farmers could manage water efficiently to prevent further yield loss and improve farm profitably.