膜下秸秆覆盖的土壤水热效应对日光温室黄瓜生长及产量的影响

Effect of Soil Moisture and Temperature on Cucumber Growth and Yield in Solar Greenhouses with Straw Mulching under Plastic Film

为了探究膜下秸秆覆盖的日光温室黄瓜根际土壤水热特征及增产机制,在统一覆盖地膜基础上,设置4个秸秆覆盖量水平0.42、0.83、1.25、1.67 kg/m^(2)(记为T1、T2、T3和T4),以无秸秆覆盖为对照(CK)进行试验。结果表明:膜下秸秆覆盖可提高黄瓜全生育期0~30 cm土壤蓄水量,生长前期蓄水效应无显著性,生长末期,处理T3较CK显著高出7.48%(P<0.05),土壤保墒效果最佳;5、10、20和25 cm土层日均温随秸秆覆盖量增加而增加,随土层加深而降低,且变化趋于平缓,5~25 cm土层温度日高峰期集中在14:00-17:00;就黄瓜生长月及全生育期而言,除15 cm土层外,膜下秸秆覆盖对各土层均有增温效应,5 cm土层比其他土层依次高出3.27%、5.57%、9.59%和12.24%;生育后期,膜下秸秆覆盖促进株高、叶片数和茎粗生长,且通过促进坐果数、黄瓜纵横径生长,达到增产效果,处理T3、T4和T2分别较CK显著提高42.95%、28.96%和24.02%(P<0.05)。综合考虑,土壤保墒增温效果和黄瓜生长及产量指标,处理T3(秸秆覆盖量为1.25 kg/m^(2))是日光温室秋冬茬黄瓜保墒调温增产的最佳膜下秸秆覆盖量。

In order to explore the characteristics of soil temperature and moisture of cucumber in the solar greenhouses and yield-increasing mechanism by straw mulching under plastic film,an experiment was carried out from September of 2020 to January of 2021.The straw mulching application rates of 0(CK),0.42(T1),0.83(T2),1.25(T3)kg/hm^(2)and 1.67(T4)kg/hm^(2)were used in field plots.The results showed that straw mulching could increase soil water storage at 0-30 cm during the whole growth period,but there was no significant difference between straw mulching treatments and CK at the early growth stage of cucumber(P<0.05).After 85 and 110 days of transplanting,T3 was the best treatment for soil moisture retention,and was significantly higher than CK by 6.05%and 7.48%(P<0.05).Straw mulching improved the average daily temperature at 5 cm,10 cm,20 cm and 25 cm soil layers,and the average daily temperature increased with the increase of straw mulching.The peak temperature at 5-25 cm soil layers was between 14:00-17:00,and the average daily temperature decreased gently with the depths of soil layers.In terms of months for cucumber growth and whole growth period,straw mulching had the effect on increase of soil temperature except for 15 cm soil layer,which was 3.27%,5.57%,9.59%and 12.24%higher at 5 cm soil layer than in 10 cm,15 cm,20 cm and 25 cm soil layer,respectively.From the elongation stage to the initial stage of fruit formation,straw mulching exhibited inhibitory effects on the growth of leaf number and plant height except for the treatment T1(P<0.05).At the late growth stage,straw mulching promoted the growth of plant height,leaf number and stem diameter.Straw mulching promoted the growth of fruit-setting number and vertical and horizontal diameters of cucumber,the effect for increasing yield was achieved.Compared with CK,under treatments of T3,T4 and T2,it was significantly increased by 42.95%,28.96%and 24.02%(P<0.05),respectively.Considering the effects of soil moisture preservation,temperature-increasing and the growth and yield of cucumber,the treatment T3(straw mulching amount of 1.25 kg/m^(2))was the best straw mulching amount for increasing the yield of cucumber in autumn and winter in solar greenhouses.