基于土壤水分下限的宁夏枸杞滴灌灌溉制度试验研究

以宁杞7号枸杞为研究对象,在宁夏同心县开展2 a田间试验.设置4个关键控水期、3个控水水平共8个处理,研究枸杞不同生育期不同水分下限条件下根区土壤含水率、叶片光合生理指标、产量与品质变化;分析其耗水规律与水分利用效率,提出基于土壤水分下限的宁夏枸杞滴灌灌溉制度.结果表明:不同水分处理枸杞根区20~60 cm土层土壤含水率最大;叶片气孔导度随土壤下限升高而增大,高水分下限处理的蒸腾速率相对较大,叶片水分利用效率则相反;生育期耗水量随土壤水分下限升高而增大,2 a增幅分别为10.8%和12.8%,平均耗水量为386.6~463.2 mm,夏果期耗水量最大且差异具有统计学意义,是关键需水期.2 a均为处理S5的产量最大分别为2 208.15和2 571.30 kg/hm²,水分利用效率最高为0.39 kg/m³;水分处理对蛋白质含量影响差异不具有统计学意义,低土壤水分下限的枸杞多糖含量相对较高;全生育期分为6个灌水期,其中萌芽期灌水(春水)为375 m³/hm²;春梢生长期、花期、夏果期、秋果期的土壤质量含水率下限分别为50%θ_f(θ_f为田间持水率),65%θ_f,65%θ_f,55%θ_f,而上限为95%θ_f;休眠期冬灌量为450 m³/hm².

Experimental study on soil moisture lower limit-based drip irrigationschedule for Lycium barbarum in Ningxia arid area

Considering Ningqi No.7 Lycium barbarum as study object,field experiments were carried out in Tongxin county of Ningxia during 2016—2017.In the experiments,there were four critical control irrigation stages and three control irrigation levels,resulting in eight treatments totally.The root soil moisture,leaf photosynthetic physiological indexes,yield and quality of Lycium barbarum were investigated in different growth stages and lower limits of soil moisture.The water consumption and water use efficiency were analyzed and a drip irrigation schedule for Lycium barbarum in Ningxia arid area was proposed based on the lower limits of soil moisture.The results show that the soil moisture in the 20-60 cm soil layer is the highest in the root area of Lycium barbarum in different treatments.The leaf stomatal conductance is increased with increasing lower limit of soil moisture,and the higher the soil moisture lower limit and the bigger the transpiration rate,but the leaf water use efficiency is opposite.The water consumption rises with increasing lower limit of soil moisture in the growth stage in 2016—2017,and their increase rates are 10.8%and 12.8%,respectively.The average water consumption is 386.6-463.2 mm and it is the largest in summer fruiting period with statistics significance,therefore,this is the critical stage.The maximum yields are 2208.15 kg/hm^ 2 and 2571.30 kg/hm ^2 in 2016—2017,respectively,and the water use efficiency is the highest at 0.39 kg/m ^3.The influence of soil moisture on quality of Lycium barbarum is not statistically significant.The content of glutinous polysaccharide is re-latively high in lower moisture treatment.The whole growth stage is divided into six irrigation stages,among which the irrigation quota in sprout stage is 375 m 3/hm^ 2(spring water).The lower limit of soil moisture is 50%θf(θf is field moisture capacity)in spring growth stage,65%θf in flowering stage,65%θf in summer fruiting stage,55%θf in autumn fruiting stage,and the upper limit is 95%θf.The irrigation quota is 450 m 3/hm^ 2 during winter dormancy.Those outcomes will provide a technical support for scientific irrigation and planting management of Lycium barbarum in arid areas.