Effect of Water-saving Technologies on Growth, Yield, and Water-saving Potential of Lowland Rice

• Main Authors: Hayat Ullah, Avishek Datta
• Format: Article
• Language: English
• Published: Universitas Indonesia 2018-12-01
• Series: International Journal of Technology
• Subjects: Alternate wetting and drying; Continuous flooding; Dry direct seeding; Water productivity; Wet direct seeding
• Online Access: http://ijtech.eng.ui.ac.id/article/view/1666

Alternative methods of rice production that use fewer freshwater inputs are crucial for sustainable rice production in the context of decreasing irrigation water availability, which may further exacerbate due to climate change. The direct seeding (DS) method of cultivation (either dry or wet) and alternate wetting and drying (AWD) are among such ways, which could contribute to decreasing irrigation water inputs in rice production without a considerable yield penalty, thus increasing water productivity. The objective of the study was to investigate the performance of a popular, lowland, Thai rice variety (Pathumthani 1) under different cultivation methods subjected to different threshold levels of AWD. The treatments involved three cultivation methods (dry direct seeding [DDS], wet direct seeding [WDS], and transplanting [TP]) and four soil moisture levels of 0, ?5, ?15, and ?30 kPa, maintained through a permanently installed tensiometer. The growth, yield components, grain yield, and water-saving potential of rice under different cultivation methods and soil moisture levels were determined. There were more unfilled grains at ?30 kPa under the DDS method. At the severe moisture stress of ?30 kPa, the DDS method resulted in a 24% higher grain yield than did the TP method, whereas the difference in grain yield between WDS and TP was nonsignificant at moisture levels of 0, ?15, and ?30 kPa. The highest water-saving potential of 62% compared with the traditional continuous flooding method was observed at ?30 kPa, which was reduced by 24–82% for the other soil moisture levels. The performance of Pathumthani 1 was better under the DDS method at all soil moisture levels. The threshold level of AWD could be ?30 kPa for soil and weather conditions comparable to the present study for its high water productivity compared with yield reduction.