土壤水分胁迫对设施番茄叶片气孔特性的影响

Effect of soil water stress on stomatal characters of greenhouse tomato leaves

为了研究土壤水分胁迫对设施番茄叶片气孔特性的影响，本研究以“金粉2号”为试材，于2013年5—8月设计4个土壤水分梯度试验／[正常灌溉（田间持水量的70%～80%）、轻度胁迫（田间持水量的60%～70%）、中度胁迫（田间持水量的50%～60%）和重度胁迫（田间持水量的30%～40%）／]，利用数码显微成像系统和数码测距软件测定了叶片气孔参数。结果表明：番茄叶片气孔长度、宽度、气孔开张度和开张比均随水分胁迫程度的增加而减小，且随着胁迫时间的延长，其减小幅度不断增大；番茄气孔长宽的减小具有同步性，但气孔长度下降更为显著；随着水分胁迫程度的增加，气孔逐渐由长卵形转变为近圆形；随着土壤水分胁迫强度的增加，气孔上表皮气孔密度逐渐增大，而气孔下表皮密度呈先减小后增大的趋势。该研究揭示了土壤水分胁迫对设施番茄叶片气孔发展的影响规律，可为设施番茄水分管理提供科学依据。

An experiment was conducted to examine the influence of soil water stress on the stomatal characters of greenhouse tomato leaves in May to August 2013. With Jingfen2 as the test material, four soil moisture grades were included in this experiment： well watered （70%-80% of water holding capacity）, mild stress （60%-70% of water holding capacity）, moderate stress （50%-60% of water holding capacity） and severe stress （30%-40% of water holding capacity）. Digital microscopic imaging system and digital measuring system were applied to measure the stomatal length, width, aperture, and density. The results showed that the stomatal length and width, stomatal aperture and open ratio of tomato leaves decreased with the increase of water stress, and the reduction amplitude increased with the extension of stress time. Tomato stomatal length and width decreased synchronously, but the stomatal length was more significantly decreased than the stomatal width with the increase of water stress. The stomata gradually changed from long ovate to suborbicular. The stomatal density of the upper epidermis increased gradually, while the stomatal density of the lower epidermis presented a trend of decreasing first and then increasing. This study provided the scientific basis for water management of greenhouse tomato.