‘LD-1'砧米良一号猕猴桃的耐涝性

Submergence tolerance of ‘LD-1' stock-grafted Actinidia deliciosa Miliang 1

关键词:  猕猴桃, 耐涝性, ‘LD-1', 砧木, 米良一号, 生理指标, 形态指标

Key words:  Actinidia, submergence tolerance, ‘LD-1', stock, Actinidia deliciosa Miliang 1, physiological indexes, morphological indexes

摘要:

猕猴桃是一类不耐涝的植物,为了解决猕猴桃的涝害问题,吉首大学近年来尝试用‘LD-1'作为猕猴桃的耐涝性砧木。该研究以米良一号实生苗砧米良一号猕猴桃和‘LD-1'砧米良一号猕猴桃为材料,观测根系淹水后叶片可溶性糖含量、丙二醛含量、叶绿素含量、可溶性蛋白质含量、SOD活性和形态的变化规律,探讨了‘LD-1'砧米良一号猕猴桃的耐涝性。结果表明:(1)米良一号实生苗砧米良一号猕猴桃根系淹水后,可溶性糖含量6 d后极显著(P<0.01)升高; 丙二醛含量8 d后显著(P<0.05)升高; 叶绿素含量和可溶性蛋白质含量没有显著变化; SOD活性6 d后显著(P<0.05)升高,8 d后不再有显著变化; 叶片2 d后出现轻度萎蔫,10 d后全部枯死。(2)‘LD-1'砧米良一号猕猴桃根系淹水后,可溶性糖的含量4 d后显著(P<0.05)升高; 丙二醛含量、叶绿素含量、可溶性蛋白质含量和SOD活性无显著变化; 叶片10 d后未出现显著的萎蔫和枯死现象,30 d后仍正常。这说明米良一号实生苗砧米良一号猕猴桃耐涝性较弱,‘LD-1'砧米良一号猕猴桃耐涝性较强,‘LD-1'作砧木显著增强了米良一号猕猴桃的耐涝性。该研究结果为‘LD-1'在米良一号猕猴桃栽培上的应用提供了依据。

Abstract:

Actinidia deliciosa Miliang 1, cultivated by a research team of Jishou University, Hunan Province, is a fruit tree with high output and high nutrition value but poor flood resistance, so the research on water stress is of great importance for its promotion. Some professors attempted to use Actinidia ‘LD-1' as rootstocks to improve the submergence tolerance of A. deliciosa Miliang 1 in recent years. But in order to further reveal the submergence tolerance of ‘LD-1' stock-grafted A. deliciosa Miliang 1 from the physiological perspective, we selected the Miliang 1 seedling stock-grafted A. deliciosa Miliang 1 and the ‘LD-1' stock-grafted A. deliciosa Miliang 1 as experimental materials, which were transplanted to flowerpots outside the laboratory at Jishou University in December, 2013. When the condition permitted, we treated the roots of those two materials with flood and non-flood group respectively in July, 2014. And in each group, we had 3 fruit trees for experiment. Besides recording morphological change in leaves of two experimental materials after 0, 2, 4, 6, 8 and 10 d waterlogging(both flood and non-flood group), we also tested other 5 physiological indices——soluble sugar content by anthrone colorimetry, malondialdhe(MDA)by thiobarbituric acid(TBA)spectrophotometric, chlorophyll content by spectrophotometry, soluble protein content by coomassie brilliant blue(CBB)G-250 and superoxide dismutase(SOD)activity by nitroblue tetrazolium. The results were as follows:(1)When the roots of Miliang 1 seedling stock-grafted A. deliciosa Miliang 1 waterlogged, soluble sugar content in leaves of those flooded tree increased very significantly(P<0.01)6 d later compared with those non-flooded group; the content of malondialdehyde(MDA)also had a significant increase(P<0.05)after 8 d; and there was no significant change in chlorophyll content and soluble protein content; the activity of superoxide dismutase(SOD)increased significantly(P<0.05)6 d later while it had no significant change after 8 d; otherwise, after 2 d waterlogging, we observed there were a small amount of leaves wilting and all leaves died after 10 d.(2)However, the damage to ‘LD-1' stock-grafted Actinidia deliciosa Miliang 1 appeared weak. Except the content of soluble sugar increased significantly(P<0.05)4 d later, the content of malondialdehyde(MDA), the content of chlorophyll,the content of soluble protein and the activity of superoxide dismutase(SOD)had no significant change; in addition, the leaves of ‘LD-1' stock-grafted A. deliciosa Miliang 1 did not wilt or die 10 d later, it also seemed normal after 30 d water stress. The results, on the one hand, obviously showed that the flooding resistance of ‘LD-1' stock-grafted A. deliciosa Miliang 1 was higher than that of Miliang 1 seedling stock-grafted A. deliciosa Miliang 1; the submergence tolerance of A. deliciosa Miliang 1 was enhanced significantly by Actinidia ‘LD-1' stock. On the other hand, this research also provides a theoretical basis for the usage of ‘LD-1' rootstocks on A. deliciosa Miliang 1.