炼苗期基质相对含水量对黄瓜幼苗贮藏特性的影响

Effect of Substrate Relative Water Content in Seedling Hardening Stage on Storage Characteristics of Cucumber Seedling

为了探究炼苗期基质含水量对黄瓜商品苗贮藏质量的影响，在炼苗期对黄瓜育苗基质进行不同含水量处理，测定了不同贮藏时间下黄瓜幼苗质量相关指标及定植后恢复生长指标，筛选了评价黄瓜幼苗贮藏质量的单一和复合指标。结果表明：随着贮藏时间的增加，所有基质含水量处理下黄瓜幼苗的叶片健全指数、淀粉含量及定植后心叶生长速度均下降。综合来看，贮藏0 d（直接移栽），基质相对含水量45%～55%处理下幼苗定植后生长恢复情况最好；贮藏2 d，炼苗期基质相对含水量30%～40%和45%～55%处理下黄瓜幼苗各项指标和定植后生长恢复能力均表现良好；贮藏4 d，幼苗质量明显劣变，但各处理间无显著差异；贮藏6 d，仅基质含水量75%～85%处理下黄瓜幼苗定植后能够恢复生长。通过相关性分析得出，贮藏期黄瓜幼苗叶片健全指数与定植后恢复生长能力的相关系数最高，可作为评价幼苗贮藏质量的单一指标；通过通径分析得出，复合指标“可溶性糖含量（mg·g-1，FW）＋86.24比叶重（g·dm-2）-474.56地下部干质量（g）”能够很好地反映定植后幼苗恢复生长能力。

To explore the effect of substrate moisture in seedling hardening stage on storage characteristics of commercial cucumber seedling,substrates of cucumber seedlings in hardening stage were treated with different water contents, their growth indicators related to quality during different storaging time,and the recovered growth indicators after transplanting were also measured. Single and composite indicators for evaluating storaging quality of cucumber seedlings were screened. The results show that with the increase of storaging time,the leaf integrity index,starch contents,and leaf growth rate of cucumber seedlings under all substrate moisture treatments were decreased. On the whole,storage for 0 day （direct transplanting）,under treatment with substrate relative water content between 45% - 55 %,the seedlings grown had the best recovery after transplanting. Storage for 2 days, under treatments with substrate relative water content between 30% - 40% or 45% - 55 % in seedling hardening stage,the various indicators of cucumber seedlings and their recovery abilities after transplanting presented well. Storage for 4 days,seedling quality deterioration was obvious,but there were no significant differences between all treatments. Storage for 6 days,only under the treatment with substrate relative water content between 75% - 85 %,the cucumber seedlings could resume growth after transplanting. By correlation analysis we concluded that the leaf integrity index of cucumber seedlings in storaging period had the highest correlation coefficient with their growth resume abilities after transplanting,which could be taken as the single indicator. Through path analy-sis,we believed that the composite index of‘soluble sugar content （mg· g-1 ,FW） ＋86.24 specific leaf weight （g·dm-2） - 474.56 underground root dry weight （g） ’ could well reflect the seedling growth recovery ability after transplanting .