栽插方式和密度对鲜食型甘薯品种干物质积累分配、块根产量及品质的影响

Effects of Planting Method and Density on the Dry Matter Accumulation,Distribution,Root Yield,and Quality of Fresh Edible Sweet Potatoes

为了确定鲁中丘陵薄地鲜食型甘薯适宜的栽插方式和密度,在大田条件下,以济薯26(J26)和龙薯9号(L9)为供试品种,每个品种设置直栽(S)和水平栽(H) 2种栽插方式,各栽插方式下设置不同栽插密度37 500(D1),52 500(D2),67 500株/hm^2(D3),研究了不同栽插方式和密度对鲜食型甘薯干物质积累分配、产量和品质的影响。结果表明,增加密度可提高两品种生长中后期植株干物质积累量,显著降低相同栽插方式下济薯26生长中期侧枝叶的干物质分配比例。相同栽插方式下,D2处理可降低龙薯9号生长后期侧枝茎干物质分配比例,并显著提高两品种生长中期的块根干物质分配比例。直栽方式下,D2和D3处理显著提高济薯26生长后期块根干物质分配比例。相同栽插方式下,D2和D3处理显著提高两品种块根可溶性糖含量和淀粉含量,D2处理可显著提高两品种块根产量。与直栽相比,水平栽显著提高济薯26生长前期D2处理和后期D2和D3处理下、龙薯9号生长中期相同密度下的植株干物质积累量;有利于提高济薯26 D1处理下、龙薯9号各密度下的块根可溶性糖含量,提高两品种单株薯重和块根产量。综合考虑产量和品质,水平栽+D2处理是本试验条件下的最优处理组合。

In order to determine suitable planting method and density for fresh edible sweet potato planting in barren hilly in the central region of Shandong Province, L9 and J26 were used as test varieties under field conditions. Each variety was planted vertically and horizontally, with planting densities of 37 500 （D1）, 52 500 （D2）, and 67 500 plants/ha （D3）. We studied the effects of different planting methods and densities on the dry matter accumulation, distribution, yield, and quality of fresh sweet potatoes. An increase in density increased the dry matter accumulation in the middle and late growth stages of the two varieties and significantly decreased the ratio of the dry matter distribution of the branch leaves of J26 planted vertically and horizontally. D2 treatment decreased the ratio of the dry matter distribution of the branch stems of L9 planted vertically and horizontally in the late growth stage and significantly increased the ratio of the dry matter distribution of the tuber roots of the two varieties planted vertically and horizontally in the middle growth stage. The D2 and D3 treatments significantly increased the ratio of the dry matter distribution of the tuberous roots of J26 planted vertically and horizontally in the late growth stage. For the two cultivars at the same transplanting method, D2 and D3 treatments significantly improved the soluble sugar content and starch content in tuberous roots and D2 treatment significantly increased the tuberous root yield of the two cultivars. Compared with vertical planting, horizontal planting significantly increased the dry matter accumulation in the early growth stage under D2 treatment and in late growth stage of J26 under D2 and D3 treatments and in the middle growth stage of L9 at the same density. Compared with vertical planting, horizontal planting increased the soluble sugar content of the tuberous roots of J26 under D1 treatment and that of L9 with different densities. Horizontal planting was also benificial for increasing tuberous root weight per plant and tuberous root yield of the two cultivars. With regard to yield and quality, horizontal planting ＋ D2 treatment is the optimal combination under the test conditions.