基于20 cm蒸发皿蒸发量制定的华北地区温室黄瓜滴灌灌水制度

试验分别于2013和2014年在中国农业科学院新乡综合试验基地进行，以20 cm蒸发皿蒸发量（E_p -20）为灌水依据，设置5种水面蒸发系数（K_cp1:0.25；K_cp2:0.5；K_cp3:0.75；K_cp4:1.0；K_cp5:1.25）代表5种灌水水平，分析了不同水量（I_r）对温室黄瓜滴灌耗水量（ET）、产量、品质以及水分利用效率（WUE）的影响，探讨了以E_p -20制定温室滴灌灌水计划的可行性.结果表明：温室滴灌黄瓜整个生育期内的耗水量在129~314 mm，耗水量随着灌水量的增加而增加.当灌水量超过0.75E_p 20时，各处理之间的产量无差异，平均单果质量、单株瓜条数和平均瓜长对灌水量的响应均存在一个阈值（0.75E_p 20）；品质方面，可溶性固形物、维生素C和可溶性糖含量均随着灌水量的增加而降低，而可溶性蛋白质含量为：K_cp2＞K_cp3＞K_cp4＞K_cp1＞K_cp5；采用修正后的Penman Monteith公式计算温室滴灌黄瓜参考蒸发蒸腾量所得结果与E_p -20呈极显著线性相关关系.可见，在华北地区日光温室黄瓜的滴灌灌水制度选用0.75倍的20 cm蒸发皿水面蒸发量作为灌水依据简单可行.

Irrigation scheduling with a 20 cm standard pan for drip-irrigated cucumber grown in solar greenhouse in the North China Plain.

An experiment was conducted in 2013 and 2014 at the Xinxiang Comprehensive Experimental Station, Chinese Academy of Agriculture Sciences. Water amount was estimated with the E_p -20 and pan coefficient. Responses of cucumber evapotranspiration (ET), yield, quality and water use efficiency (WUE) to different drip irrigation amounts (K_cp1: 0.25; K_cp2: 0.5; K_cp3: 0.75; K_cp4: 1.0; K_cp5: 1.25) were investigated. The possibility of developing drip irrigation scheduling using the 20 cm pan was also discussed. Results showed that the seasonal evapotranspiration of cucumber ranged between 129 and 314 mm, and the water consumption generally increased with the increase in drip irrigation water amount. There was no significance difference in cucumber yield between the treatments with K_cp >0.75, and the responses of mean fruit mass, number and length to water amount had a threshold value (0.75E_p -20). Regarding the fruit quality, the contents of total soluble solids, vitamin C and soluble sugar slightly decreased with increasing the irrigation water amount, while the soluble protein content varied in order as: K_cp2＞K_cp3＞K_cp4＞K_cp1＞K_cp5. There was a significant positive correlation (P<0.01) between the pan evaporation and the reference crop eva potranspiration estimated based on a modified Penman Monteith equation. In a conclusion, the drip water amount calculated with K_cp of 0.75 and the 20 cm pan were easy and feasible for cucumber cultivation in solar greenhouse in the North China Plain.