黄瓜种子萌发对NO3-胁迫的响应及耐盐性评价

通过培养皿发芽试验,研究了0、14、98、182 mmol/L NO3-对7个黄瓜品种种子萌发的影响,并用隶属函数法对它们的耐盐性进行综合评价.结果表明:与对照相比较,14 mmol/L NO3-处理使7个黄瓜品种种子的相对发芽率、相对发芽指数、耐盐指数9、6 h后的鲜重、干重和超微弱发光(UWL)强度均增加,而98、182 mmol/L NO3-处理下这些指标均逐渐降低;各幼苗的电解质相对渗漏率在14 mmol/L NO3-处理后降低,而在98、182 mmol/LNO3-处理后其值逐渐增加;随着NO3-浓度的增加,各黄瓜品种的胚根总面积、总长度逐渐减少.各黄瓜品种半致死浓度值(LC50)以津园5号的最大(192.3 mmol/L),新秀4号的最小(105.0 mmol/L).不同黄瓜品种耐盐性的综合评价显示,津园5号、新泰密刺为耐盐品种,新秀4号、神农春五为盐敏感品种,其他为中度耐盐品种.

Response and Stress Tolerance Evaluation of Different Cucumber Cultivars under NO-3 Stress

The effects of 0,14,98,and 182 mmol/L NO-3 on germination of 7 different cucumber cultivars in Petri dishes were studied and the NO-3 stress tolerance of different cucumber cultivars was evaluated.The results indicated that the relative germination rate,relative germination index,salt stress index,fresh weight,dry weight and ultraweak luminescence(UWL) intensity were increased after 14 mmol/L NO-3 treatment,but decreased after 98 and 182 mmol/L NO-3 treatments.The relative electrolyte leakage decreased after 14 mmol/L NO-3 treatment,but increased with 98 and 182 mmol/L NO-3 treatments.The total area and total length of radicals were decreased with the increase of NO-3 concentration.The value of LC50 of ’Jinyuan No.5’ and ’Xinxiu No.4’ were 192.3 mmol/L,105.0 mmol/L,respectively.In all of the 7 cultivars,’Jinyuan No.5’ and ’Xintaimici’ were salt tolerant cultivars,while ’Xinxiu No.4’ and ’Shennongchunwu’ were salt sensitive cultivars and others were intermediate salt tolerance by subordinate function values analysis.