滴灌方式对‘赤霞珠’葡萄幼苗根冠功能的调控效应

研究地下穴贮滴灌(自主设计)、膜下滴灌、地表滴灌3种滴灌方式对酿酒葡萄品种‘赤霞珠’幼苗根冠功能的影响.结果表明： 膜下滴灌和地下穴贮滴灌较地表滴灌更促进植株生长，其中地下穴贮滴灌主要促进根系的生长，膜下滴灌主要促进地上部的生长；在20～60 cm土层，地下穴贮滴灌处理根表面积、根体积、根系活力和超氧化物歧化酶活性均高于地表滴灌和膜下滴灌处理，表明地下穴贮滴灌可有效促进根系下扎，提高土壤深层根系的生理活性；同一灌水周期后期地表滴灌处理较早受到干旱胁迫的影响，地下穴贮滴灌和膜下滴灌处理叶片净光合速率(P_n)和气孔导度(g_s)均高于地表滴灌处理，灌水7 d后膜下滴灌处理12:00—14:00实际光化学效率(Φ_PSⅡ)、光化学猝灭系数(q_P)低于地下穴贮滴灌处理，表明叶片荧光日进程中膜下滴灌受到的光抑制程度大于地下穴贮滴灌；对植株根冠功能的相关分析表明，有效增加20~40 cm土层根系的根量指标，保持根系生理活性在较高水平，可促进整体植株地上部生物量的增加和总生物量的积累.综合分析表明，地下穴贮滴灌较膜下滴灌、地表滴灌对植株根冠生长及功能调控有一定优势，可作为果树节水灌溉技术的潜在替代技术.

Effects of drip irrigation methods on the regulation between root and crown function of ‘Cabernet Sauvignon’ seedlings.

The objective of this experiment was to study the effects of three irrigation methods, i.e., subsurface drip irrigation with a tank system (SDI), plastic film mulched drip irrigation (MDI), and conventional drip irrigation (DI) on the regulation between root and crown function of Vitis vinifera ‘Cabernet Sauvignon’ seedlings. The results showed that both the SDI and MDI systems promoted the growth of the grape seedlings compared with DI, with the SDI system promoting the root growth, and MDI system promoting the aboveground growth. Root area, root volume, and root activity and SOD enzyme activity in the SDI treatment were greater than those of MDI or DI treatment in the 20-60 cm soil layer. SDI treatment increased root penetration and physiological activity. Symptoms of drought stress appeared earlier in DI treatment than in either MDI or SDI treatment in the same watering schedule. Net photosynthetic rate (P_n) and stomatal conductance (g_s) of leaves were higher in SDI and MDI treatments than in DI treatment. Φ_PSⅡ and q_P at 12:00-14:00 were lower in the MDI treatment than in SDI treatment at 7 d after irrigation, suggesting that the degree of photoinhibition in the fluorescence process in MDI treatment was more than that in SDI treatment. The high biomass and physiological activity of roots in the 20-40 cm depth could increase both of total plant biomass and aboveground biomass. The regulation between root and crown function was better in SDI treatment than in MDI and DI treatments. Therefore, SDI could be used as an alternative technique of water saving irrigation practices.