Tác giả: Lê Văn Hòa (email@example.com), Phạm Phước Nhẫn, Phan Thị Bé Sáu
Flooding is one of the factors damaging agricultural production seriously, particularly for paddy rice areas. Intensive rice culture from 2 to 3 consecutive crops per year with short intervals causes straws and stubbles un-decomposed under field water which might change physical, chemical and biological characteristics of soil that affect rice growth and yield. Therefore the studywas conducted from May 2013 to September 2013, in the greenhouse of Department of Plant Physiology and Biochemistry, College of Agriculture and Applied Biology, Can Tho University to investigate the effects of straws and stubbles incorporation under artificial flooding on growth and yield of IR64-Sub1 rice variety. The pot experiment was arranged in Completely Randomized Designs with two factors: (A) three types of straw and stubbles incorporation; and (B) two flooding treatments. The results showed that straws and stubbles incorporation at 60 cm depth of water continuously in 15 days at seedling stage altered some soil characteristics. Parameters such as pH, EC, Eh, dissolved oxygen, Al3+, Fe2+, PO4 3-, NH4+ exerted positive effect on rice growth and delayed harvest time up to 20 days in comparison to that of the control. The incorporation of burnt straws and stubbles showed effectiveness in rice yield and reduced unfilled-seed percentage significantly. Fresh straws and stubbles incorporation under anaerobic condition caused impact on IR64-Sub1 growth and yield. In summary, flooding delayed rice growth and prolonged cropping time; in contrast, incorporation of burnt straws and stubbles promoted rice growth and yield.