干旱胁迫和盐胁迫对海岛棉种子活力的影响

Effects of Drought Stress and Salt Stress on Seed Vigor of Gossypium barbadense L.

研究干旱胁迫和盐胁迫对海岛棉种子萌发活力的影响,筛选出2个适应于新疆种植的海岛棉优势品种。使用水培法,对20份海岛棉种子(系)在NaCl胁迫和PEG-6000(聚乙二醇6000)胁迫下种子的发芽率、发芽势、根长、芽长、湿重、干重、电导率、SOD酶活性、POD酶活性和可溶性蛋白10个生理指标进行测定;分析其海岛棉种子品种在干旱胁迫和盐胁迫时体内的酶活性和可溶性蛋白的变化规律;通过对海岛棉种子活力的测定和排序确定出2个对干旱胁迫和盐胁迫抗性较强的品种。结果显示在干旱胁迫下种子的发芽率、发芽势、发芽指数和活力指数随干旱程度的增加下降明显,在25%PEG条件下,海岛棉种子不萌发;虽然低盐浓度对棉花种子萌发有促进作用,但海岛棉种子的发芽势、发芽指数和活力指数随盐浓度增加下降明显。干旱和盐胁迫综合作用会抑制海岛棉种子的萌发,根据综合性评价6号材料311(新海5号)和19号材料377(吉扎67号)为抗旱耐盐的品种。

To study the effects of drought stress and NaCl stress on seed germination vigor of island cotton,and select two predominant varieties of Gossypium barbadense L. suitable for planting in Xinjiang. The germination rate,germination potential,root length,bud length,wet weight,dry weight,electrical conductivity,SOD activity,POD activity and soluble protein of 20 sea island cotton seeds(lines) under NaCl stress and PEG-6000 stress were measured by hydroponics method. The changes of enzyme activity and soluble protein of Island Cotton under drought and NaCl stress were analyzed;Two varieties with strong resistance to drought stress and salt stress were identified by measuring and sequencing the seed vigor of Gossypium barbadense L. Meanwhile,the varieties rule of enzyme activity and soluble protein in Gossypium barbadense L. seed were analyzed during drought stress and salt stress;two stronger drought-resistant and salt-tolerant varieties were decided by the evaluation of Gossypium barbadense L. seed vigor. The results showed that the germination rate,germination potential,germination index and vigor index of the seeds under drought stress decreased significantly with the increase of drought degree. Under the condition of 25% PEG,the seeds of Hainan cotton did not germinate. Although low salt concentration promoted the germination of cotton seeds,the germination potential,germination index and vigor index of sea island cotton seeds decreased obviously with the increase of salt concentration. The aggravation of drought and salt stress would inhibit the germination of island cotton seeds. According to the comprehensive evaluation,No. 6 material 311(Xinhai 5) and No. 19 material 377(Jizha 67) are drought-resistant and salt-tolerant varieties.