关键词: 水稻, 抛秧, 技术体系

Abstract: Abstract: A series of research and applications for broadcasting-seedling of rice was conducted by agriculture technical extending departments, institutes and universities from 1980’s. The remarkable advance was obtained. The cultivation technical system of broadcasting-seedling of rice, which integrated labor saving and hardship lessening with high-yielding and greater efficiency, was adapted to crop and planting systems and rural economics of China, has being established. The system was composed of 6 parts as follows. 1. The mechanism was clarified for standing and establishing of seedling after transplanting on broadcasting-seedling of rice. The standing and establishing of seedling behave three sequential mutual processes included physical, physiological and morphological aspects through rooting rapidly anchored to soil and basal stem bending up coinstantaneous. Because seedling with soil and its root integrality, the recovering time from injury was shortened in contrast to the manual transplantation in the same seedling but washing root. The standing of non-upright seedling needed 2~5 days for young seedling, 5~6 days for middle and 7~10 days for large. During standing and establishing, because injury slightly, status of water, nutrient, photosynthetic and so on in plant of broadcasting-seedling of rice are superior to the manual transplantation and growing of root, leaf, tiller in quantity and quality are so. The orders of recovering from injury accelerate or increase rooting, leaf emergence, plant nutrient content, matter cumulating during standing. The standing and establishing of broadcasting-seedling of rice is influenced indirect or direct by seedling self included quality, age, with soil or no, posture after transplanting and by environment included light, temperature, air and so on. 2. Spatial distribution of plant positions and its eco-physiological effects were analyzed on broadcasting-seedling of rice. The spatial distribution, primordial foundational characteristics, differenced from the manual transplantation. The planting depth is characterized with shallow and variously in the perpendicular (-0.5~2.5cm). So crown (tiller nodes) inserts into the soil shallowly and variously in depth, resulted in diversities seedling posture after transplanting. The environment around tiller node or stem in soil was changed remarkably. In general, some ecological factors around crown included temperature, nutrient, air, bind force of soil and so on are improved. But these factors fluctuate notably because the crown lies on soil-water-air boundary layer. So stress chances of rice growth may be underwent increasingly from these factors. The depth of tiller nodes in soil strongly influence the growing of organ included leaf, tiller and root and the developing of population included uniformity, lodging and yield. The optimal depth of crown is about 1.5cm. Distribution of plant positions is characterized by quasi-even random on level. It determines mainly the spatial distribution of plant. Additional relative uneven effect of growing was intensified in the perpendicular, canopy height. The main elements of canopy micro climate included light, temperature, humidity and wind are improved. 3. The foundational characteristics of growth and development and yield formation were discovered on broadcasting-seedling of rice. There were 4 superiorities as follows.①The population grew rapidly at the beginning and produced more tillers. Plant-type was radial. The intensity of growth appeared strong. ②Light is well-distributed intra-plant. Canopy of population is well-proportioned vertically. Green leaf area per unit of land area is more. Photosynthetic regime, which structure was better and scale was larger, was formed.③Ears and grains per unit of land area may be contained more. Photosynthetic layer of population is thicker during grain filling stage. The source is sufficient and sink is larger during late period. So capacity of cumulative matter is exuberant. ④Root system is strong and vigorous and benefits absorbing of nutrient and water. But there were 3 inferiorities as follows.①The percentage of productive tillers to total is slightly low.②The proportion of ear under low is high slightly. So size of ear is small slightly. ③The capacity of root lodging resistance becomes weaker under the sodden and soft soil, 4. The formation of high-yielding and its regulating way were elucidated on the broadcasting-seedling of rice. In contrast to the manual transplantation, there were characteristics on high-yielding as follows. ①The seedling are well distributed.②The growth and development of population is well-harmonious.③The percentage of productive tillers to total is at the high-level. ④The uniformity of population is well-kept. The main growth indexes for 600kg per mu grain are as follows. ①The seedlings stands during 1 leaf age after transplanting and tillers appear at 2 leaf age according to the occurrence

Key words: Rice (oryza sativa L.), Broadcasting-seedling of rice, Cultivation technical system