安徽农业科学

[目的]筛选适宜拉萨地区推广种植的不同类型鲜食玉米的合理种植密度,提高西藏地区鲜食玉米的经济效益。[方法]在前期品种试验基础上,选取3个综合性状优良的鲜食玉米品种,开展合理种植密度研究。以双玉104(甜玉米)、白玉203(糯玉米)和白玉304(甜糯玉米)为材料,采用随机区组试验设计,设置4个种植密度梯度(82 500、111 000、132 000、165 000株/hm²),系统分析种植密度对鲜食玉米农艺性状(株高、穗位高、穗长、穗粗)、籽粒产量与营养品质(水分、蛋白质、脂肪、粗淀粉、可溶性总糖、氨基酸含量)、秸秆产量与饲用品质(水分、蛋白质、粗脂肪、粗灰分、淀粉、粗纤维、中性洗涤纤维、酸性洗涤纤维含量)的影响,并筛选最优种植密度。[结果]种植密度对参试品种株高、穗位高和穗长均有调控作用,但对穗粗无显著影响。单株产量方面,密度梯度对双玉104、白玉203的单株净穗重和3个品种的单株秸秆重有显著影响;单位面积产量方面,3个品种的单位面积净穗重和单位面积秸秆重在132 000株/hm²时较高,各品种的籽粒与秸秆产量均随密度的增加呈先升高后下降趋势。综上所述,3个品种在较高种植密度(132 000株/hm²)下获得最高总体产量,但是种植密度对籽粒和秸秆品质的影响并未发现明显规律。[结论]该研究明确了拉萨地区不同类型鲜食玉米的适宜种植密度,验证了“一茬两收”模式在西藏地区的可行性。

[Objective]To screen the appropriate planting densities for different types of fresh-ear corn suitable for promotion in the Lhasa region,with the aim of improving the economic benefits of fresh-ear corn in Xizang.[Method]Three fresh-ear corn varieties with excellent comprehensive traits were selected based on previous variety trials.Shuangyu 104(sweet corn),Baiyu 203(glutinous corn),and Baiyu 304(sweet and glutinous corn),were planted under four density gradients(82 500,111 000,132 000,165 000 plants/hm²) using a randomized block design.The effects of planting density on agronomic traits(plant height,ear height,ear length,ear diameter),grain yield and nutritional quality(moisture,protein,fat,crude starch,total soluble sugar,amino acid content),as well as straw yield and feeding quality(moisture,protein,crude fat,crude ash,starch,crude fiber,neutral detergent fiber,acid detergent fiber content) were systematically analyzed to identify the optimal planting density.[Result]The study found that planting density significantly influenced plant height,ear height,and ear length of the tested varieties,but had no significant effect on ear diameter.In terms of individual plant yield,the density gradient significantly affected the net ear weight and straw yield per plant for Shuangyu 104 and Baiyu 203,as well as the straw yield per plant for all three varieties.Regarding yield per unit area,the net ear weight per unit area and straw weight per unit area of the three varieties were relatively high at a planting density of 132 000 plants/hm²,besides,grain and straw yields for all three varieties increased first and then decreased with the increase of planting density.In summary,all three varieties achieved the highest overall yield at a higher planting density(132 000 plants/hm²).However,no clear pattern was observed regarding the effect of planting density on grain and straw quality.[Conclusion]This study identifies the appropriate planting densities for different types of fresh-ear corn in the Lhasa region and verifies the feasibility of the “double harvests from a single cropping cycle” model in Xizang.