Effects Of Simplication Pruning And Plant Density On Growing Development And Yield Of Garlic-cotton Intercropping System In Southwest Area Of Shandong Province

The transplanting seeding model has been developed under the garlic-cotton rotated system in Southwest Shandong province. Regarding transfer management, the transfer density of plant is an important factor to inhibit cotton yield. High plant density not only resulted in high canopy density but also increase the input of labor. Actually, the seeding transfer density less than27000plant hm"2, which is lower in this region than in other area, gave birth to low boll numbers of plant. Besides, the abundant rainfall in recent years, boll formed fast and high boll rot rate under the bottom restricted cotton yield and severely influenced the quality of cotton.To attain the best combination of plant density and the model of cotton cultured with monopodium under the garlic-cotton rotated system in Southwest Shandong province and to reach high-yield and-efficiency purpose,the effect of varying both density and the model of cotton cultured with monopodium on the growth and yield of cotton, the quality of fibre and economic interest was investigated using split-plot design with2factors, which were conducted in Jining, Jinxiang,and Yutai experimental points in2011.The model of cotton cultured with monopodium and plant density. differently influenced on the growth and height of cotton to some extent. The retention of vegetative branches delayed the growth of cotton and prolonged4days for boll opening stage. There was no significant impact of plant density on the growth of cotton in the definite range of plant density. Both the vegetative branches retention and the increase of plant density slightly decreased the height of cotton.The ratio of "three kinds of bolls" of cotton, i.e., bolls formed in pre-summer, summer and autumn, significantly depended on both plant density and the model of cotton cultured with monopodium. The retention of vegetative branches markedly reduced the ratio of bolls developed in pre-summer and autumn, but significantly enhanced the percent of bolls developed in summer. In comparison with the removal of vegetative branches, the retention of vegetative branches increased by7.48%,9.65%and2.17%of bolls developed in pre-summer, summer and autumn, respectively. The high plant density resulted in decreasing the percent of bolls developed in summer, contrarily augmented that of bolls developed in autumn. The retention of vegetative branches at33000plant hm-2increased by19.97%of boll formed in summer but decreased by12.25%of boll formed in autumn compared with the removal of vegetative branches at45000plant hm-2.The retention of vegetative branches and low plant density significantly reduced boll rot rate. The boll rot rate decreased by11.01%under retention of vegetative branches at33000plant hm"2in comparison with the removal of branches at45000plant hm-2. The model of cotton cultured with monopodium and optimum plant density efficiently enhanced the quality of cotton.There is no significant effect of the model of cotton cultured with monopodium and plant density on the function leaf caducity. In comparison with the removal of vegetable branches, the retention of vegetable branches decreased by1.01%of yellow leaf in the beginning of boll opening stage, and did not result in the earliness caducity. The percentage of yellow leaf with high plant density was slightly higher than with low plant density.The interaction of the model of cotton cultured with monopodium and plant density was significant on cotton yield. Cotton yield with the retention of vegetative branches is higher than with the removal of vegetative branches, but the difference is not significant. The yield of cotton with medium plant density observed was higher than that with low or high plant density treatments. The highest yield was the retention of vegetative branches at33000plant hm-2, with the lint yield1932kg hm-2. The cotton yield was equivalent between the retention of vegetative branches at27000plant hm-2and the removal of vegetative branches at33000plant hm-2. The single or interacted effect of the model of cotton cultured with monopodium and plant density on biomass, yield components and economic index took place. The biomass of cotton was increased by the retention of vegetable branches and enhancing plant density. Compared with the removal of vegetative branches, the retention of vegetative branches enhanced the boll numbers per unit area and increased by6.1%of cotton yield, but reduced the weight of single boll. Lint percentage was not significantly influenced by both the model of cotton cultured with monopodium and plant density.The earliness trait of cotton under the retention of vegetative branches is better than that with the removal of vegetative branches。There is no obvious difference of fiber quality under the model of cotton cultured with monopodium and varying plant density treatments. Five indexes of fiber quality with the retention of vegetable branches were better than the removal of vegetable branches. High plant density treatment had higher length and better uniformity fiber compared with low plant density.The economic interest was significantly affected by the model of cotton cultured with monopodium and plant density of cotton. The economic interest with the retention of vegetable branches was higher than with the removal of vegetable branches. Exorbitant plant density of cotton decreased the economic interest. The plant density with33000plants hm-2, which is the highest economic interest treatments, enhanced by2760yuan of the economic interest in comparison with33000plants hm-2.Under the low or medium plant density, the retention of vegetable branches generally made the congregation of bolls formed in the sunny area, resulted in the optimum ratio of "three kinds of bolls" of cotton, significantly decreased the rot boll rate and effectively offset the yield losing resulted from low plant density. Therefore, the economic interest with the retention of vegetable branches was enhanced. The retention of vegetable branches combined with plant density with33000plants hm-2was best optimum set under the garlic-cotton rotated system in Southwest Shandong province.