覆膜和密度对‘陇薯7号’产量及不同质量块茎分布的影响

Effects of Film Mulch Planting and Density on Yield and Distribution of Tubers with Different Masses in ‘Longshu 7’

以‘陇薯7号’原种为试验材料,采用裂区设计,研究覆膜和密度对其成熟期、产量及其构成因素以及不同质量块茎分布的影响,综合分析产量、成本、效益,提出高寒阴湿区‘陇薯7号’繁种适宜的种植方式和合理的种植密度,为其北繁南种脱毒种薯繁育技术体系的形成提供理论支持,以及在南方冬作区的大面积推广奠定基础.结果表明:黑色地膜覆盖能使‘陇薯7号’成熟期提前15d,生育期缩短11d,产量增加57.19%.随着密度的增加,有效株数增加,单株结薯数减少,单薯质量降低,产量显著增加.在试验设计的密度范围内,产量与密度呈线性正相关,在最高密度下获得最高产量.随着密度的增加,<20g、20~50g块茎比率呈直线上升趋势,>100g块茎比率呈直线下降趋势,50~100g块茎比率因种植方式不同而变化不同,地膜覆盖种植,呈先升后降的趋势,密度13.5×10^4hm^-2时达到最高,露地种植则表现为持续下降的趋势.地膜覆盖主要影响20~50g和>100g块茎比率.综合分析产量、成本和效益,以地膜覆盖密度增加到13.5×10^4hm^-2为试验最佳处理,产量48938.89kg/hm2,纯收益1673.53元/hm^2,20~50g块茎比率27.15%,50~100g块茎比率36.08%.建议在高寒阴湿区繁育‘陇薯7号’脱毒一级种采用黑色地膜覆盖种植,密度13.5×10^4hm^-2,块茎按质量大小进行分级.

‘Longshu 7’is suitable for planting in the southern winter cropping area,but its late harvest is in the high cold and humid areas because of its long growth period.The virus-free seed potato breeding is dominant in Gansu province,and the dormancy of seed potato can not be quickly lifted during winter sowing period,so this limits its large-scale popularization in the winter cropping area to a certain extent.In order to explore the effective ways to make the maturity period in advance and increase yield of‘Longshu 7’,planting methods and density experiments were carried out to provide theoretical foundation for virus-free seed potato breeding technology system of‘Longshu 7’in North Gansu,and to lay a foundation for its large-scale popularization in southern winter cropping areas of Gansu.Using‘Longshu 7’as material,split plot design was used to study the effects of different planting methods and densities on maturity,yield and its components,and tuber distribution of different qualities.The yield,cost and benefit were analyzed comprehensively.The suitable planting methods and reasonable planting densities for‘Longshu 7’in high cold and humid areas were put forward.The results showed that black plastic film mulching could make the maturity of‘Longshu 7’15 days in advance,shorten its growth period by 11 days and increase its yield by 57.19%.With the increase of density,the number of effective plants increased,the number of tubers per plant decreased,the quality of tubers per plant decreased,and the yield increased significantly.Within the density range designed by the experiment,the yield increased linearly with the density,and the highest yield was obtained at the highest density.With the increase of density,the tuber ratios of<20 g and 20-50 g showed a straight upward trend,and those of<100 g showed a straight downward trend.The tuber ratios of 50-100 g varied with different planting methods.The coverage planting of black plastic film showed a first upward and then downward trend,which it reached the highest density at 135 000 hm^-2,while the open-field planting showed a continuous downward trend.Planting methods mainly affected the tuber ratio of 20-50 g and>100 g.Comprehensive analysis of yield,cost and benefit showed that the best treatment increased the planting density of black film mulching to 135 000 plants/hm^2.The yield was 48 938.89 kg/hm^2,the net income was 1 673.53 yuan/hm^2,the tuber ratio of 20-50 g was 27.15%,and the tuber ratio of 50-100 g was 36.08%.It is suggested that the virus-free first-class‘Longshu 7’should be planted with black plastic film mulching in cold and humid areas with a density of 135 000 hm^-2,and the seed potato should be graded according to their quality.