土壤水势对烤烟生长及其耗水特性的影响

The Effects of Soil Water Potential on the Growth and Water Consumption of Flue-cured Tobacco

为筛选负压灌溉条件下烤烟适宜的土壤水势,于2012年在山东诸城市利用负压灌溉装置设置了3个不同的土壤水势,在田间原位盆栽条件下考察了土壤水势对烤烟生长、耗水特征、干物质积累与分配、水分利用效率(WUE)的影响。结果表明,在负压灌溉条件下,土壤水势维持在-20^-10 k Pa范围内,能使烤烟植物学性状生长优良;烟株耗水量、耗水强度、干物质积累总量(DAM)及叶干重比例均随土壤水势增大而增加,但各生育期的耗水模数与灌溉方式无关;WUE随土壤水势降低而增大,在同一土壤水势条件下随生育期推移而增加。从潜在产量和水资源高效利用等角度综合分析,提出基于负压灌溉下不同生育期应采用不同土壤水势值进行供水,具体为伸根期适宜的土壤水势范围为-30^-20 k Pa,旺长期约为-10 k Pa,成熟期约为-20 k Pa。

In this paper, the effect of soil water potential on the growth, water consumption characteristics, dry matter accumulationand distribution, water use efficiency （WUE） of flue-cured tobacco was studied. With 3 levels of soil water potential maintained byusing a negative pressure irrigation device, pot experiments in situ field were carried out. The results showed that, the botanic traitsof tobacco was well when soil water potential was in the range of -20--10 kPa; Water consumption, water consumption intensity,total dry matter accumulation （DMA） and the ratio of leaf dry weight decreased when soil water potential increased, while waterconsumption modulus of different growth periods changed little with changed soil water potential; WUE increased when soil waterpotential decreased, and increased as the periods of flue-cured tobacco growing in the same soil water potential. For efficientutilization of irrigation water, different soil water potential should be maintained in the different growth periods, the suitable soilwater potential for flue-cured tobacco at various growth stages as follows： the range of -30--20 kPa at root stretch stage, about -10kPa at fast growing stage, and about -20 kPa at mature stage.