Study On The Green High Yield And Benefit Planting Patterns Of Double-season Rice In Changsha County

In order to explore the pattern of green high yield and benifit planting technique of double-season rice in Changsha County,this study carried out a fixed point tracking investigation on three planting patterns,namely,seedling throwing,conventional transplanting and "Three One " transplanting,through consulting data,field investigation and questionnaire investigation.The basic situation of double-season rice planting in Changsha County,the technique of double-season rice variety collocation,seedling breeding and transplanting,reasonable close planting technology,fertilizer and water management technology and control of diseases and insect pests were analyzed,and the cost benefit of three planting modes of double-season rice were compared.The technological model suitable for green and high yield planting of double-season rice in Changsha County was put forward.The main results were as follows:1.Changsha County is rich in precipitation,warm and light,four distinctive seasons,very suitable for double-season rice planting.The cultivated land area of the whole county is 199700hm2,the total planting area of existing crops is 137880hm2,the sowing area of grain crop is about 84000hm2,and the sowing area of rice is about 72410hm2,accounting for 51% of the farming area and 85.7% of the grain crop area.The sown area of double-season rice was stable in 72220hm2,accounting for 97.2016 of the total sowing area of rice,the average yield per mu of early rice was 410 kg,and that of late rice was 508 kg per mu.2.The main varieties of early rice include Zhongjiazao 17,Zhongzao 39,Xiangzaoyu 42,Zhuliangyou 189,Zhuliangyou 819,etc.,sowed on March 25 th,transplanted in mid-April,and harvested in mid-July.The whole growing period is 106~112d.The main varieties of late rice varieties are Taiyou 390,Shanyou 4949,and Hyou 518.They are planted around June 25 th,transplanted in mid-July,harvested from the end of October to the beginning of November,and the whole growing period is 112-128 days.3.The main way of raising seedlings is tray(including floppy disc,hard disk),the large planting households mainly use the greenhouse to raise seedlings,the individual mainly uses the double film to raise the seedlings,and the transplanting way is mainly the throwing seedling,which accounts for about 71% of the planting area of the double-season rice.Next is the machine transplanting seedling,a few direct seeding,in recent years began to popularize "Trinity" the machine transplanting the cultivation,In 2016,we will promote the "Three One" machine insertion technology.4.The fertilization technique basically popularized the soil testing formula fertilization,the early rice mainly applied the base fertilizer,the topdressing tillering fertilizer,the late rice applied the first tillering fertilizer and the one panicle grain fertilizer on the basis of the sufficient base fertilizer.5.Prevention and control of diseases and insect pests is based on the principle of specialization and defense.It focuses on the promotion of natural enemies control technology,sex attractant insecticide technology,frequency vibration lamp trapping technology,and “duck and duck” co-culture prevention technology.These technologies prevent major insect pests.The efficiency reached 80% or more,drastically reduced the cost of medication,and improved the quality of rice.The price of rice was more than 20% higher than that of ordinary rice,and the income increased by about 220 yuan per mu per quarter.Trichogramma,sexual attractants,frequency-vibration lights,and rice-duck co-education were 3,255 yuan/hm2,1,185 yuan/hm2,763 yuan/hm2,and 5,505 yuan/hm2,respectively,compared with traditional methods.6.According to the comparative analysis of the three planting patterns of throwing seedling with early Xian and late Xian rice,"Three One" machine transplanting with early Xian and late Geng rice,and traditional machine transplanting with early as late dual-purpose."Three One" machine transplanting can save 50%-70% seed quantity and reduce nitrogen fertilizer amount 30%,which can prolong the growing period effectively,and has more choice space for variety collocation,and the effect of increasing yield is obvious.In order to achieve the goal of green high yield and efficiency of double-season rice,it is suggested that early maturing early rice and middle and late maturing high quality late rice varieties should be selected in Changsha County,and "Three One" machine planting method should be adopted to control diseases and insect pests through rice-duck co-breeding,so as to further optimize the management of fertilizer and water and increase the degree of mechanization.