铝浸种对小白菜种子萌发和幼苗生理特性的影响

以2个小白菜品种南京长梗和抗热605为试验材料,研究了不同浓度铝浸种后种子萌发和幼苗生理特性的变化.结果 表明,10～5000μmol/L的铝浸种处理对2个小白菜品种的发芽率无明显影响.5000 μmol/L的铝处理显著降低了小白菜的发芽势、发芽指数和活力指数.种子萌发后,南京长梗和抗热605分别在100和1000 μ...

EFFECT OF SEED SOAKING WITH ALUMINUM ON SEED GERMINATION AND SEEDLING PHYSIOLOGY OF PAKCHOI

Two pakchoi （Brassica chinensis L.） cultivars＇ （NJCG and KR605） seeds were soaked in the alumnium （Al） solutions with five concentrations （0,10,100,1000,5000 μmol/L） for 12 hours to study the effect of Al on the seed germination and seedling physiology. It was found that 10~5000 μmol/L Al3＋ soaking could not significantly change the germination rate of two cultivars,but 5000 μmol/L Al3＋ could significantly decrease the germination power,germination index and vigor index. After seed germination,root length,fresh weight of root and shoot were significantly decreased at 100 μmol/L Al3＋ in NJCG and 1000 μmol/L Al3＋ in KR605. At the seventh day after germination,10~100 μmol/L Al3＋ had no significant effect on malonaldehyde （MDA） content and peroxidase （POD） activity. However,1000~5000 μmol/L Al3＋ significantly increased MDA content and POD activity in pakchoi leaves of both cultivars compared with the control. Soluble sugar （SS） content was promoted firstly and then reduced with increasing Al concentrations. These results indicated that pakchoi in seed germination period was more tolerant to Al than it in seedling growth period,and different pakchoi cultivars had different reaction to Al. Under middle and high Al concentrations,the toxic effect of Al on pakchoi was due to the great accumulation of reactive oxygen free radical,and the promotion of leaf POD activity and SS content was helpful to alleviate the Al photoxicity.