滨海滩涂盐碱地甜高粱生长和地上部干物质积累特性的研究

摘 要：【研究目的】明确不同密肥水平下滨海滩涂盐碱地甜高粱生长特性、干物质积累特征，为盐碱地甜高粱高产栽培提供理论基础。【方法】以甜高粱ST008为试验材料，采用二因素随机区组设计，研究不同种植密度及氮肥用量水平对盐碱地甜高粱农艺性状、产量及茎秆糖锤度的影响，利用通径分析，对甜高粱不同生育阶段干物质积累与生物产量、糖锤度之间的相互关系进行了相关性分析。【结果】甜高粱ST008在种植密度120000株/hm2、氮肥用量300kg/hm2条件下获得的生物产量、籽粒产量和茎秆含糖量较高，株高、叶片数、茎粗等较为适宜。通径分析表明，拔节至抽穗期地上部干物积累量和生物产量、茎秆含糖锤度之间呈极显著的正相关关系，对提高生物产量、茎秆糖锤度的贡献最大。【结论】盐碱地甜高粱在密度120000株/hm2、施氮量300kg/hm2水平下生物产量最高。提高拔节至抽穗阶段甜高粱植株的光合生产是提高甜高粱产量、含糖量的关键。

Growth characteristics and above ground dry matter accumulation of sweet sorghum grown on seashore saline soil

Abstract: 【OBJECTIVE】The aim of this article was to study growth characteristics and above ground dry matter accumulation of sweet sorghum (Sorghum bicolor L.) under diffferent planting density and nitrogen application amount levels, and provide a theoretical basis for high yield cultivation of sweet sorghum in seashore saline soil. 【METHOD】Using the method of two factors randomized block experiment to investigate the effects of planting density and nitrogen application amount on growth characteristics, dry matter accumulation and the interrelationship among biomass yield, sugar brix of ST008 plant grown in seashore saline soil were analyzed by correlation analysis and path analysis. 【RESULTS】The suitable planting density and nitrogen application amount for ST008 was 12000 plant/hm2 and 300 kg/hm2, respectively. Under this condition, the plant height, leaf number and stem diameter of sweet sorghum were maintained within reasonable ranges, and higher biomass yield and sugar brix was achieved. The dry weight of above ground plant from jointing to heading stage and stem yield and sugar content were positively correlated respectively, which had highest direct path coefficient contributed to the stem yield and sugar content. 【CONCLUSION】The biomass yield of sweet sorghum wa highest when planting density and nitrogen application amount for ST008 was 12000 plant/hm2 and 300 kg/hm2, respectively . The key point of increasing sweet sorghum yield and sugar content was to enhance the photosynthetic production after the jointing stage..