The Research On Characteristics Of Yield Formation Of Different Double Season Rice Varieties And Planting Density Under The Mechanical Transplanting

In this study,using a large area test method.In the2012trial, double season rice bothchoosen different type transplanter, including same spacing transplanter and wide andnarrow row transplanter,transplanting eight common varieties in field trials;In the2013trial, double season rice both choosen wide and narrow row transplanter transplanting twodifferent types of varieties in field trials, each varieties are set eight planting density, theyconsist of two spacing(11.5cm(L1)、13.6cm(L2)) and four seedling taking area（1.05cm2（S1）、1.44cm2（S2）、1.83cm2（S3）、2.23cm2（S4））.Trough in-depth study of ricepopulation growth, population quality, yield formation characteristics, breedcharacteristics,etc. Provide a theoretical basis for selecting mechanical planting varieties,transplanter type, suitable planting density in double season area.The results show that:(1)The research on characteristics of different double season rice varieties under themechanical transplantingIn the early rice varieties, higher yield varieties include Lingliangyou268andXinfengyou22, their yields are more than7500kg/hm2under the different transplantertreatment; In the late rice varieties, higher yield varieties include Tianyouhuazhan、Tianyou998、 Wuyou308and Fengyuanyou299, their yields are more than9000kg/hm2.High-yielding varieties are panicles and grains coordination, have a relativelyhigh seed rate and grain weight, Specific performance of moderate growth period, betterseedling quality, better transplanting quality, strong ability of anti-sik injury, quicklyturning green after transplanting, higher panicle,can differentiation more rachis andspikelets, more dry matter accumulation, strong ability to absorb nitrogen, maintain a highLAI in the mid and later growth period, strong root activity after heading, leaf SPAD has aslower rate of decline.(2)Effect of different double season rice planting density on the yield formation under themechanical transplantingDouble season rice yield were expressed as L1>L2, yield first increased and thendecreased with the increase of the seedling area taking. The highest yield treated as L1S3in each treatment of the early rice Zhuliangyou819, the lowest yield treated as L2S1; Thehighest yield treated as L1S4in each treatment of Zhongjiazao17, the lowest yield treatedas L2S1. The highest yield treated as L1S2in each treatment of the late rice Zhendao11,the lowest yield treated as L2S1; The highest yield treated as L1S1in each treatment ofWufengyou T025, the lowest yield treated as L2S4. Analysis shows that panicles andgrains per panicle are mainly affected in double season rice.Setting rate and grain weightdifference is small of each treatment.With the increase of the seedling area taking, missplanting rate of double season ricevarieties decrease, spiker rate lower;With the decrease of spacing and increase of theseedling area taking, LAI increased in each period, dry matter increased, transmittancedecreased, leaf SPAD drop...