Characteristics Of High-yield Formation And Related Cultivation Technique In Mechanical Transplanted Changyou 1

High-yield formation characteristics and cultural techniques for strong rice seedling, such as sowing amounts, seedling age at transplanting and most rice seedling techniques, were studied systemicly for mechanical transplanted Changyou 1 at Changshu institute of agricultural science and 1000 mu demonstration plot of Xinzhuang town at Jiangsu province during 2004 - 2006. The results were as follows:1. High-yield formation characteristics of mechanical transplanted Changyou 1:(1)The higher number of population panicles coordinating with larger panicles can obtain adequate number of total population spikelets, maintain normal seed set and grain weight, form high-yield structure, and achieve high-yield stably. Yield was determined by number of population spikelets. Spikelets and yield of high-yield populations per mu were increased by 17.40% and 18.60% respectively on those of general yield populations. Spikelets and yield of super-high-yield populations per mu were increased by 34.13%, 36.20% respectively over those of general yield populations. The seed set and 1000 grain weight had almost identical performance from general to high till super-high yield level of Changyou 1.(2) It was suggested to firstly increase medium-term growth materials reasonably and improve later growth capacity and the ultimate biological yield to form the material foundation of high-yield. The economic coefficient of different yield levels varied slightly by comparing the three yield levels, the population biological yield formation and their economic coefficient. The rice grain yield improving was mainly dependent on the increasing of total biological yield. Comparing the high-yield and super-high-yield populations with the general populations, biological yield in later stage was increased by 30% and 50% in later stage, followed by the medium-term, up 25%, 27% respectively.(3) Population photosynthetic potential was increased gradually with the passage of growth stage, reaching the maximum late. Population net assimilation rate rose first and then declined, the minimum value was at prophase. High-yield and super-high-yield populations had obvious advantages during the middle and later period, and the general yield population was at early stage, whose dry matter production was less than high-yield and super-high-yield populations.(4) It was also suggested to improve population material productivity with rational dynamic models of rice tiller and LAI. Compared to general yield populations, high-yield and super-high-yield populations burgeoned quickly after transplanting and reached the high peak seedling stage early, 5-10 days ahead of time, after which the total number of tillers declined gently. Therefore high-yield and super-high-yield populations had obviously increased panicles and high percentage of effective panicles per mu. Within a certain extent, the utilization of light was better when the population LAI was higher during growth period in paddy field. LAI of high-yield and super-high-yield populations was higher than general yield populations at every growth stage.2. In order to get strong seedlings suitable for mechanical transplanting, the sowing amount was the key. The results showed that the yield of sowing amount of 80 g/plate was significantly higher than the others. It could produce a greater storage capacity and efficient material production capacities to realize the unification of configuration and function of the population and the cost saving of seeds.Between transplanting seedling age and the quality there was a very close relationship, which determined the rice individual development foundation to a great extent, and affected the yield formation of mechanical transplanted rice finally. In this research, transplanting at the 20 days age of seedlings, the dry matter production, leaf area index, plant type, nitrogen absorption and rice quality were performed a significant advantage than other treatments, achieving the purpose of storage expansion and source strength and obtaining high yield finally.The quantity of heat and the fresh water resources condition are superior in Tai Lake rice area, the techniques of raising rice seedlings could be innovated adjusting measures to local conditions. Strong seedlings, which were the basis of high yield formation, could be bred suitable for mechanical transplanting by taking simple and easy two-layer film raising, sparse and even seeding and transplanting at the right age.