Innovative furrow ridging fertilization under a mechanical direct seeding system improves the grain yield and lodging resistance of early indica rice in South China

Abstract

• Furrow ridging fertilization increased grain yield of direct-seeded early indica rice in South China. • Higher yield in furrow ridging fertilization was attributed to high panicle and biomass production. • Furrow ridging fertilization improved the stem lodging resistance compared with surface fertilization and whole-layer fertilization. • Furrow ridging fertilization had the significantly highest lignin content among the fertilization methods. Precision hill-drop direct seeding via mechanical drilling is a novel planting pattern that provides benefits such as high grain yields and lodging resistance in direct-seeded rice in South China, however, the effects of different fertilization methods on yield performance and lodging resistance capacity under mechanical direct seeding systems are still unclear. Hence, a field experiment was conducted over two years with two early indica cultivars to determine the grain yield formation and lodging characteristic of the rice plants under three fertilization methods, including furrow ridging fertilization (FRF), surface fertilization (SF), and whole-layer fertilization (WLF). We found that FRF significantly increased the grain yields of the two cultivars by 6.04 %–28.25 % compared with SF and WLF; this result was attributed to the high panicle and biomass production. FRF also significantly improved the seedling emergence rate of the early indica rice cultivars and increased the aboveground total dry weight and harvest index. In addition, compared with SF and WLF, FRF significantly enhanced the stem lodging resistance of direct-seeded rice cultivars and reduced the lodging index, especially at the third internode. The physical parameters of the stem, including the internode length, thickness and wall thickness, dry weight of internode, and lignin content of the test internodes, improved under FRF due to the high associated breaking-resistance strength and lodging index. These results indicate that furrow ridging fertilization was beneficial for increasing the grain yield and lodging resistance of direct-seeded early indica rice.