| Rice direct seeding, a way of sowing rice seeds in the field directly, can save labors, work, and cost, can cause precocity and improve the output, and also benefits scale planting. In order to meet the increasing needs of extension of rice direct seeding in Nanping area, this thesis introduces the status quo of rice direct seeding both domestically and abroad, and analyses the exiting problems about direct seeding in Nanping area. Basing on experiments, the author summarizes following key points in rice direct seeding in Nanping Area:1. Whether a strain of rice is a proper one or not depends on the time when the rice grows in the field. As single-crop rice, it is reasonable to choose a long growing period strain. And the strain should have a strong resistance to lodging and middle level of tiller ability. The rate of forming spikes should be high and the seedlings should be cold-resistant. The root systems of them are vital. And it is not easy to wither at the latter stage. The most suitable strains in northern part of Nanping Area are II Youhang2 and II You125,meanwhile Teyou716 and II Youfu819 are fairly good strains. In southern part of Nanping Area, the most suitable strains are Teyou716 and II Youfu819, meanwhile Youhang2 and II You125 are fairly suitable.2. Sowing time of the rice direct seeding has a great effect on the rice germination and the output. For instance, if the sowing time is too early, the seed will rot or postpone germinating and this causes insufficient seedlings and low output. If the sowing time is too late, the seedlings are easy to rot because of high temperature and water stain, this causes low rate of germination and short growing period, also reduces the output finally. The suitable sowing time ranges from the 5th day of May to 20th day of May. In northern part of Nanping Area, the most suitable time is during second ten-day period of May. In southern part of Nanping Area, the most suitable time is during first ten-day period of May.3. Under normal climate, the number of seedling is interrelated with the density of sown seeds. If the quantity of sown seeds is not enough, the seedlings are sparse and it is impossible to yield highly. On the contrary, over-number sowing also causes low output because of low ear rate, low seed-setting rate and less grains per spike. Currently, the density of rice seeding should be controlled between 1.25kg～1.75kg/667m2.On the abnormal air condition, the density of rice seeding can be a little higher, but it should not be over 2.00kg/667m2.4. During the sowing time, the water in the field affects rice germination greatly. If it doesn't rain during the period from sowing to germination, seeds should be wet enough before they are sown in the field to make sure that the rate of germination is high. While it rains during the period from sowing to germination, a good sowing method is sowing seeds followed by irrigation and drainage, i.e. after we sow the seeds in the field, water should be pumped into the field to keep 2-3 centimeters deep water just in case the seeds are washed off by the rain. When the rain stops, water must drain away in time so that the seedlings can take roots in the earth.5. The weeds in the field of direct seeding rice come out very early, there are usually too many weeds around the field and the density of the weeds is high. Therefore the weeds in the field of direct seeding rice do great harm to seedlings and they should be cleaned as thoroughly as possible. One of effective ways to remove the weeds is to use chemical liquid. It is always necessary to spray chemical liquid soon after the seeds are sown. Once more is also needed and it had better happen when the seedlings are during three-leaf coved time. If it happens when the seedlings are during one-leaf coved time, we should spray the chemical liquid third time when the seedlings are during five-leaf coved time.6. The tiller time of the direct seeding rice is very early and the tiller ability is strong, which may cause a too large colony of rice and lodging. If Paclobutrazol is sprayed when it is during one-leaf coved time or when it is at the end of tiller period, and if the field is raked when the effective ears are 70%-80% of the total ears, then the condition of rice colony can be improved, the area of lodging can be effectively reduced and the output will rise.
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