为了优选Cd低积累或Cd高抗性番茄品种,以前期初步筛选的4个番茄品种(普罗旺斯、瑞提娜、凯特2号和908)为研究对象,通过水培试验详细对比镉胁迫下不同番茄品种幼苗生长与抗性指标的差异特征.结果表明:在不添加Cd的条件下,番茄品种908在株高、根长、总生物量以及MDA和叶绿素含量上均表现出最高的自然特征;普罗旺斯在CAT活性上表现最为突出;瑞提娜在POD活性上表现最高.在Cd胁迫条件下,低镉含量胁迫对普罗旺斯根系的生长有促进作用,比对照增长24.72%,其他品种变化不大;瑞提娜株高在中、高Cd含量胁迫下的响应最为敏感,受到了明显的抑制作用,其他品种无明显变化.4个番茄品种幼苗中的CAT活性在低、中等Cd胁迫时均明显增强,增幅为12.58% ~84.91%;在高Cd胁迫时4个品种CAT活性大幅下降,抗性功能严重削弱.品种908的POD活性在中、高Cd胁迫时大幅增强,增幅为76.07%和72.65%;瑞提娜POD活性大幅下降,抗性严重遭受影响.在4个品种中,908地上部和根部的Cd含量最高,为其他品种的3~12倍,普罗旺斯最低,4个品种的转运系数均<1.在同等Cd胁迫条件下,908植株吸收到体内的高Cd浓度诱导了抗氧化酶活性的高增加幅度,反映了品种908植株对活性氧清除能力强于其余3个品种.综上,在中、高Cd胁迫下选定普罗旺斯为Cd低积累番茄品种,908抗性最强且Cd含量较高,属于高Cd抗性品种.%In order to optimize Cd low accumulation or Cd high resistant tomato varieties,in this paper,4 toma-to varieties(Provence,Ruitina,Kate 2 and 908) were selected as the research objects,and the differences of growth index and resistance index of tomato seedlings under cadmium stress were compared in detail by hydroponics experi-ment. The results showed that 908 had the highest natural characteristics in plant height,root length,total biomass, MDA and chlorophyll content under the condition of nutrient solution without Cd;Provence showed the most promi-nent in CAT activity;Ruitina showed the highest activity on POD. Under the condition of Cd stress,low Cd content promoted the growth of root system of Provence,which was 24.72% higher than that of CK,other varieties did not change much;the plant height of Ruitina was most sensitive to the stress of middle and high Cd content,other varie-ties had no obvious change. CAT of four tomato varieties under low and medium Cd stress has increased 12.58%-84.91%;the activity of CAT decreased sharply and the resistance function was seriously weakened under high Cd stress. The resistance of POD in 908 to medium and high Cd stress was increased,and the enzyme activity was en-hanced by 76.07% and 72.65%;the activity of POD in Ruitina decreased sharply and the resistance was seriously affected. The contents of Cd in shoots and roots of 908 were the highest among the four varieties,3-12 times of other varieties,Provence was the lowest,and the transport coefficient of four varieties were all<1. Under the same Cd stress,the high Cd concentration absorbed by the 908 plants induced a high increase in the activity of antioxi-dant enzymes,reflected that the scavenging ability of 908 plants to reactive oxygen species was stronger than that of the other three varieties. In conclusion,under the medium and high Cd stress,Provence was selected as Cd low ac-cumulation tomato variety,908 had the strongest resistance and higher Cd content,belonging to the high Cd resistant varieties.
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