马铃薯叶型和种植密度对产量组分的影响

最佳种植密度有利于对不同叶型马铃薯品种的田间管理,而且在高产同时可以获得最佳产量组分。为研究马铃薯叶型和种植密度的相互关系,找到不同叶型品种的最佳种植密度,选取株型直立的中晚熟代表品种Atlantic（叶上冲型）和甘农薯7号（叶平展型）,固定行距70cm,设置30、25、20、15和10cm 5个株距,测定了植株性状、叶绿素荧光参数和块茎产量组分,并分析了不同种植密度下2个品种性状差异以及植株性状和产量组分之间的相关性。田间鉴定表明,随着种植密度的增加,2个品种的株高、节间距、披垂度和叶面积指数增加,茎粗、垂角和叶夹角降低,光合系统Ⅱ最大光化学效率F_v/F_m增加,但实际光化学效率Φ_PSII降低。相对于叶上冲型品种Atlantic,叶平展型品种甘农薯7号披垂值显著增加。株距为15~30cm时,2个品种种植密度的提高均可以显著增加单株产量、单株结薯数和小区产量。结果表明,叶平展型品种甘农薯7号在株距25cm、叶上冲型品种Atlantic在株距20cm时,植株冠层结构分布最佳,商品薯率和小区产量较高,为最适种植密度。

Effects of Potato Leaf Type and Planting Density on Yield Components

The optimum planting density is not only beneficial to the field management of potato varieties with different leaf types,but also beneficial to the optimum yield components.In order to obtain the optimal planting density of potato varieties with different leaf types,the relationship between leaf type and planting density was studied.Two typical middle-late erect type potato varieties,Atlantic(uprush-leaf)and Gannongshu 7(spreading-leaf)were used as materials.Five plant spacing(30,25,20,15 and 10cm)and fixed row spacing(70cm)were set in the experiment.The indexes of plant architecture traits,fluorescence parameters and yield components of two varieties were investigated.In addition,the correlations between plant architecture traits and the yield components under different plant spacings were determined and analyzed.The field experiment showed that,with the increasing of plant spacing,the plant height,plant internode length,leaf bend degree,leaf area index,and the maximum photochemical efficiency of PSⅡ(Fv/Fm)increased,while the stem diameter,leaf drooping angle,leaf angle,and the actual photochemical efficiency of PSⅡ(ΦPSⅡ)decreased.Compared with Atlantic,the leaf bend degree of Gannongshu 7 increased significantly.Within the specific plant spacing ranging from 15 to 30cm,increasing plant spacing could significantly increase the yield per plant,tuber number per plant and plot yield.These results indicated that the optimal planting spacing was 25 and 20cm for spreading-leaf variety(Gannongshu 7)and uprush-leaf type variety(Atlantic),respectively,which had the reasonable canopy structure,the higher commodity rate and plot yield.