夜间补光对黄瓜幼苗形态的调节与补光方式的确定

Regulation of LED Night Lighting on Growth and Morphology of Cucumber Seedlings and Process of Night Lighting

为确定光质夜间延时补光对不同生长阶段黄瓜幼苗形态的影响,制定黄瓜育苗夜间延时补光模式,对LED夜间延时补光对黄瓜幼苗形态发育的影响进行了试验研究。选取'津春四号'黄瓜为试材,以下胚轴长、子叶面积、茎粗、叶面积、节长、干物质量、叶绿素含量以及壮苗指数为指标,研究使用红光(R,630 nm)和红蓝混合光(RB,630 nm∶660 nm=8∶2)两种LED光源夜间延时补光4 h对不同生长阶段黄瓜幼苗形态的影响,利用Logistic曲线对叶面积增长速率进行拟合。结果表明:子叶期红光延时补光幼苗子叶面积和茎粗最大,分别比对照组提高了61.60%和19.55%;一叶期红光延时补光幼苗叶面积和茎粗最大,分别比对照组提高了25.11%和14.72%;成苗期红蓝光延时补光幼苗叶面积、茎粗、干物质量、叶绿素含量和壮苗指数最大,分别比对照组提高了41.92%、17.75%、45.45%、21.92%、200.00%。利用红光夜间延时补光能够促进前期(子叶期和一叶期)黄瓜幼苗的生长,红蓝混合光夜间延时补光可促进后期(二叶期至成苗期)黄瓜幼苗的生长、提高幼苗壮苗指数。

The effects of stages were investigated lighting on growth with different light photomorphologenesis, and the method of night and morphology of cucumber seedlings in different quality to improve seedling cultivation through lighting for cucumber seedlings were discussed. Cucumber seedlings were irradiated with 35 μmol/（m^2·s） red （R） or red and blue （RB） light from light emitting diodes （LED） for 2 hours in the night （ 19：00 - 21 ： 00） at the temperature of 18 - 20℃. The effects of night lighting on growth, hypocotyls length, cotyledon area, stem diameter, leaf area, internodes length, dry weight, chlorophyll content and seedling index of cucumber seedlings at different stage were measured. Logistic curve was used to fitting the growth rate of leaf area. The cotyledon area and stem diameter were improved by 61.60% and 19.55% respectively compared to contrast at cotyledon stage, and leaf area and stem diameter were improved by 61.60% and 19.55% respectively compared to contrast at one leaf stage with R light night lighting. After three leaves stage, leaf area, stem diameter, dry weight, chlorophyll content and seedling index of cucumber seedlings with RB night lighting were improved by 41.92% , 17.75% , 45.45% , 21.92% , 200% compared to contrast, respectively. Night lighting could improve the growth and health index of cucumber seedlings. R light and RB light could improve the growth and health index of the earlier period （cotyledon stage and one leaf stage） and later period （after two leaves stage） cucumber seedlings, respectively. The method of using R light for early period and RB light for later period as night light could improve the quality of cucumber seedlings.