关键词: 水稻, 直播, 移栽, 抗倒伏, 产量

Abstract: 【Objective】The objective of this study was to investigate the effects of direct seeding cultivation on the growth period, lodging resistance, yield and economic benefits of different types of rice varieties, in order to provide a theoretical basis for the application and promotion of mechanized direct seeding rice.【Method】 For the early rice In 2020 and 2021, the conventional rice varieties Guiyu 9, Guiyu 11, Guiyefeng, Guangliangxiang 2 and hybrid rice Y Liangyou 1, which have a large area in Guangxi production, were used as test materials, in the field, Using the traditional manual transplanting as a control, the field is accurately direct seeding, For each treatment, there were three replicates. A split plot design was used in this experiment with planting method as the main plot, with rice varieties as the split plot, and set up three replications. The length of the growth period was observed, the morphology of main stem and the characteristics of the basal stem, as well as the lodging indicators such as breaking resistance, bending moment and lodging index was calculated, the yield and yield components were measured at the maturity stage, and the cost and economic benefits were calculated.【Result】(1) The growth period of direct seeding was shortened by about 2-6 days, which was mainly reflected in the period from sowing to the beginning of young spike. (2) the lodging resistance of direct seeding rice is relatively poor, and its plant height, center of gravity height and panicle dry weight are lower than that of transplanted rice; the stem thickness, wall thickness, fresh weight and dry weight of its N2 stem are also lower than that of transplanted rice, and the length of the stem is that the direct seeding rice is higher than that of transplanted rice, which may be the main reason for the weak lodging resistance of the direct rice. (3) Among the varieties tested, the actual yields of the remaining four rice varieties were lower than those of transplanted under direct-seeded cultivation, except for Yliangyou1. For varieties with relatively short growth period in the test materials, the yield under direct seeding conditions is significantly lower than that of transplanting, while for varieties with relatively long growth period，the yield difference between planting mothods is not significant, among the yield components, the increase in the number of grains per panicle and the seed setting rate are the main factors for increasing the yield of direct seeding rice. (4) From the analysis of economic benefits, among the varieties tested, Guiyu No. 11, which has a shorter growth period, has a significantly lower yield and economic benefit in direct seeding method, the economic benefits of direct seeding rice of the remaining four varieties were higher than those of transplanted rice. The main reason for this is that direct seeding rice saves labor costs in seedling and transplanting link.【Conclusion】At present, it is an urgent to develop a light and simple production model of rice with the main goal of preserving area and increasing efficiency. Compared with transplanted rice, direct seeding rice has obvious advantages such as shortening the growth period and reducing production costs. and there is a certain risk of lodging, the yield is easily affected by variety characteristics and environmental factors. Therefore, in the direct seeding cultivation of early rice, lodging-resistant varieties with medium maturity, reasonable stem length at the base, thick stems and thick stem walls can be selected. In cultivation management, the proportion of ear fertilizer should be appropriately increased to compensate for insufficient number of grains per panicle and seed setting rate can improve the yield of direct seeding rice.

Key words: rice, direct seeding, artificial transplanting, lodging resistance, yield