水盐胁迫对不同品种棉花苗期光合和荧光参数的影响

Effects of water and salt stress on photosynthetic and fluorescence parameters of different cotton varieties at seedling stage

以新疆小海子灌区主栽棉花品种‘塔河2号’、‘新陆中56号’、‘新陆中87号’为试验对象,采用完全随机盆栽试验,设置不同程度土壤盐分胁迫(S1:3 g·kg^(-1)、S2:4.5 g·kg^(-1)、S3:6 g·kg^(-1))和不同灌水上、下限,以田间持水量为标准(W1:灌水上限为60%、灌水下限为50%;W2:灌水上限为70%、灌水下限为60%;W3:灌水上限为80%、灌水下限为70%),对棉花叶绿素SPAD值、光合和荧光参数进行分析。结果表明:S1处理在0~30 cm土层返盐程度最大值为27.44%,S2处理和S3处理分别为68.44%和64.39%;棉花苗期除最大电子传递产量以外,所有光合和叶绿素荧光参数与品种之间的相关性都表现为差异极显著(P<0.01),而土壤盐分主要对G_(s)、T_(r)和Φ_(PSII)、qP、Y(N0)、α、ETR_(max)、IK产生显著影响,灌水下限仅对Φ_(PSII)、Y(N0)影响显著(P<0.05);‘塔河2号’品种在W3S1处理下的棉花G_(s)显著大于W3S2处理92.1%,‘新陆中56号’品种棉花P_n和G_(s)在W1S1处理下显著低于其他处理19.2%~68.2%,‘新陆中87号’品种棉花S1处理和S3处理下的W3灌水处理,其G_(s)和T_(r)较其他灌水处理显著增加39.4%~53.1%和10.6%~20.8%。因此,‘塔河2号’品种棉花对盐分处理更加敏感,‘新陆中56号’品种棉花在低盐土壤中,50%θ(田间持水量)的土壤含水率会显著降低光合参数的提升,‘新陆中87号’品种棉花在W3灌水处理下更有利于生长。

Using the main cotton varieties ‘Tahe 2,' ‘Xinluzhong 56,' and ‘Xinluzhong 87' from the Xiaohaizi irrigation area in Xinjiang,this study set water amounts as the standard for irrigation(W1:upper limit 60%,lower limit 50%;W2:upper limit 70%,lower limit 60%;W3:upper limit 80%,lower limit 70%).The SPAD values,photosynthetic rates,and fluorescence parameters were analyzed under varying levels of soil salinity stress(S1:3 g·kg^(-1),S2:4.5 g·kg^(-1),S3:6 g·kg^(-1)) and different irrigation thresholds.The results showed that the maximum value of 0~30 cm soil salt return was 27.44% for S1 treatment,68.44% for S2 and 64.39% for S3 treatment.In addition to the maximum yield of electron transfer at the cotton seedling stage,all the correlations between photosynthesis and chlorophyll fluorescence parameters showed significant differences(P<0.01).However,soil salinity mainly produced significant effects on G_s,T_(r) and Φ_(PSII),qP,Y(N0),α,ETR_(max),and IK.The lower limit of irrigation only had significant effects on Φ_(PSII) and Y(N0).The G_(s) of ‘Tahe 2' cotton were significantly greater by 92.1% in W3S1 treatment than that of W3S2 treatment,and the P_(n) and G_(s) of ‘Xinluzhong 56' were significantly lower than W1S1 treatment by 19.2%~68.2% under S1 and S3 treatments.W3 irrigation treatment in cotton ‘Xinluzhong 87' and T_(r) increased by 39.4%~53.1% and 10.6%~20.8% compared with other irrigation treatments.Therefore,‘Tahe 2' cotton was more sensitive to salt treatment.The moisture content of ‘Xinluzhong 56' cotton in the soil of 50%θ(field water capacity) fields significantly reduced the improvement of photosynthetic parameters.‘Xinluzhong 87' cotton was more conducive to growth under W3 irrigation treatment.