不同土壤水分条件下小麦光合特性的研究

Study on Photosynthetic Characteristics of Wheat under Different Soil Moisture Conditions

为了探讨小麦节水灌溉栽培技术,以穗型大小不同的2个小麦品种山农20(大穗型品种)和山农21(小穗型品种)为试材,在露天池栽条件下于小麦返青期后开始对2个小麦品种进行不同土壤含水量的水分胁迫处理,土壤含水量均设田间持水量的100%(水分过量)、80%(适宜水分)、61%(轻度干旱)和40%(严重干旱)4个处理,从小麦旗叶的光合速率(Pn)、气孔导度(Gs)、细胞间隙CO2浓度(Ci)和蒸腾速率(Tr)4个方面,研究了不同土壤水分条件对小麦旗叶光合特性的影响。结果表明:干旱在短期内可导致小麦生育后期旗叶光合速率和气孔导度上升,细胞间隙CO2浓度下降,但对蒸腾速率影响较小。在干旱年型小麦生产上,多选用小穗型品种如山农21。在华北地区可适当减少灌溉次数,以发挥冬小麦对干旱的适应性,达到节水、增产的目的。

In order to study the water saving irrigation cultivation technology of wheat , taking 2 wheat cultivars Shannong 20 （ large spike type cultivar ） and Shannong 21 （ small spike type cultivar ） with different sizes of panicle type as test materials, water stress with different soil water contents was treated after turning green period in the open pond cultivation conditions, soil water contents were 100% of field capacity （excess water）, 80% of field capacity （ suitable water ） , 61% of field capacity （ mild drought ） and 40% of field capacity （ severe drought） respectively, and the effects of different soil moisture conditions on photosynthetic characteristics of wheat flag leaf were studied from the 4 aspects of Pn, Gs, Ci and Tr.The results showed that moderate drought and drought could increase the Pn and Gs of wheat flag leaf , decrease the Ci, Drought could lead to wheat flag leaf Pn and Gs rised in the short term, the Ci decreased at the later stage, but the effect on Tr was little.Small spike type cultivars should be chosen in dry years wheat production such as Shannong 21.Irrigation frequency should be reduced properly in the northern regions, in order to play the adaptability of winter wheat to drought and achieve the purpose of water saving and production increasing.