硫肥对河西走廊紫花苜蓿植株性状、产量及品质的影响

研究了施硫肥S0(0kg/hm2)、S1(16.5kg/hm2)、S2(33.0kg/hm2)、S3(49.5kg/hm2)4个水平对河西走廊紫花苜蓿生物学性状、产量及营养品质的影响。结果表明:S1和S2处理显著增加了紫花苜蓿主茎长和侧茎长,S1的分枝数显著高于S2和S3处理,不同硫肥水平对紫花苜蓿主茎节数和侧茎节数没有显著影响;S3主根粗显著小于S0,S1和S2处理,S1主茎粗显著大于S0和S3处理;S1茎叶比显著低于其他处理的茎叶比;S1和S2显著增加了紫花苜蓿第1茬干草产量,S1的紫花苜蓿第2茬干草产量显著高于S2和S3处理,不同硫水平对紫花苜蓿第3茬干草产量没有显著影响,S1处理的紫花苜蓿总干草产量显著高于其他处理;S0紫花苜蓿粗蛋白含量显著低于其他处理;S1的粗脂肪含量显著高于S3处理;不同硫肥水平对紫花苜蓿粗纤维含量没有显著的影响;S1和S2的粗灰分含量显著高于S0和S3处理;S1中性和酸性洗涤纤维含量在所有处理中最低;S1处理的干物质采食量、可消化干物质和相对饲用价值都显著的低于其他处理。施硫肥水平为16.5kg/hm2时,有利于紫花苜蓿的生长、产量和营养价值的提高,而当硫肥量超过33.0kg/hm2时,紫花苜蓿干草产量和品质开始下降。

Effect of sulfur fertilizer on biological characters,yield and quality of alfalfa in Hexi Corridor,Gansu

The effect of sulfur fertilizer on biological characters,yield and quality of alfalfa(Medicago sativa ) was studied in Hexi Corridor,Gansu with 4 sulfur fertilizer levels of S0,S1,S2 and S3(0,1 6.5,33.0 and 49.5 kg/ha).The results showed that the stem length were higher at S1 and S2 levels,the branch number at S1 level was significantly higher than that of S2 and S3,the node number in stem was not significantly different among sulfur levels,the main root diameter was the highest at S3,the main stem diameter at S1 level was significantly higher than that at S0 and S3 levels,the stem leaf ratio was highest at S1 level.The dry matter yield of first har-vest was higher at S1 and S2 levels,the dry matter yield of second harvest at S1 level was significantly higher than that at S2 and S3 levels,and it was not significantly different among levels for the third harvest.The total dry matter yield at S1 level was the highest.The crude protein content was the highest at S0 level and the crude fat content at S1 level was significantly higher than that at S3 level.The crude fiber content was not significant-ly different among different sulfur levels,the crude ash contents at S1 and S2 levels were significantly higher than that at S0 and S3 levels.The neutral and acid detergent fiber contents at S1 level were the lowest.The DMI,DDM and RFV were the lowest at S1 level.The growth,dry matter yield and quality were better while the sulfur level was 1 6.5 kg/ha.The dry matter yield and quality decreased while sulfur level was over 33.0 kg/ha.