重庆地区叶菜用甘薯不同栽植密度下茎尖产量及其食用品质评价

Evaluation of stem tip yield and edible quality in different planting densities of leaf-vegetable sweet potato in Chongqing area

【目的】探讨叶菜用甘薯茎尖产量与种植密度的关系,并对不同品种及不同采收时期茎尖食用品质进行评价,为叶菜型甘薯品种在重庆地区的推广种植提供参考。【方法】引进叶菜用甘薯品种鄂菜薯1号和福菜薯18与当地常用品种万薯7号进行生长期性状比较及品种、密度两因素试验,调查地上部主要形态特征,计算试验期间8次茎尖采收鲜产量总和,测定不同采收时期可食茎尖10 cm部分干物质、维生素C（Vc）、粗蛋白、可溶性糖和粗纤维含量,并进行食用品质评价。【结果】不同种植密度下,3个甘薯品种茎尖产量均表现为27.0万株/ha〉22.5万株/ha〉18.0万株/ha。与对照万薯7号相比,鄂菜薯1号和福菜薯18地上部植株生长旺盛,藤叶产量均超过60000.00 kg/ha,茎尖食味清香,颜色翠绿,综合评分满分。品质指标测定结果表明,鄂菜薯1号和福菜薯18干物质平均含量分别为10.55%和9.26%（鲜基）,Vc平均含量为455.13和420.58 mg/kg（鲜基）,可溶性糖平均含量为7.54%和6.49%（干基）,粗蛋白平均含量为24.63%和25.53%（干基）,粗纤维平均含量为11.28%和12.88%（干基）;在6-9月间随采收月份的延迟,茎尖干物质增加,水分减少,粗纤维含量增加,Vc含量表现为8-9月高于6-7月,可溶性糖含量以8月最高,6-8月茎尖粗蛋白含量明显高于9月。【结论】在栽植密度18.0万-27.0万株/ha范围内,3个甘薯品种的茎尖产量均随密度的增加而增加。其中以福菜薯18和鄂菜薯1号茎尖产量较高,食用口感好,营养丰富,是适宜在重庆地区推广种植的叶菜型甘薯品种。

： [Objective]Through investigating the relationship between the stem tip yield and planting density of leafvegetable sweet potato, and evaluating the stem tip edible quality of different varieties harvested from different periods, practical references were provided for the planting leaf-vegetable sweet potato in Chongqing area. [Method]The study was carried out by comparison test of the vegetable sweet potato variety Ecaishu 1 ,Fucaishu 18 and locally common variety Wanshu 7 in growth period traits, together with variety and planting density experiments,investigation of the aboveground morphological characteristics,calculation of the total stem tip yield for 8 times harvest, determination of the dry matter content, vitamin C （Vc） content, protein content, soluble sugar content and crude fiber content of 10 cm edible stem tip harvested from different periods ,and lastly evaluation of eating quality. [Result]Under different planting densities ,the yield order of 3 varieties of sweet potato stem tip was 270000 strains/ha〉225000 strains/ha〉180000 strains/ha. Compared with the control group,Wanshu 7,Ecaishu 1 and Fucaishu 18 thrived,both with total yield more than 60000 kg/ha. The green stem tip tasted fragrant and comprehensively scored full marks. The results of quality index test suggested that for Ecaishu 1 and Fucaishu 18, the average dry matter contents was 10.55% and 9.26% （fresh basis）respectively. The average of Vc contents was 455.13 and 420.58 mg/kg （fresh basis） respectively. The average of soluble sugar contents was 7.54% and 6.49% （dry basis） respectively. The average of crude protein contents was 24.63% and 25.53% （dry basis） respectively, and the average of crude fiber contents was 11.28% and 12.88% （dry basis）respectively. Furthermore ,from June to September ,when the later harvest was conducted, the stem tip dry matter content increased ,water content decreased, and crude fiber content increased. The Vc content of August to September harvest was higher than that of June to July. Soluble sugar content of August harvest reached the highest. The crude protein content of June to August harvest was obviously higher than that of September. [Conclusion ]In the planting density of 180000-270000 strains/ha, the yield of 3 varieties of sweet potato stem tip increases as the density increases. Among them, with high yield, good taste and rich nutrition, varieties Ecaishu 1 and Fucaishu 18 are highly recommended for local cultivation.