不同苹果砧木对缺锌胁迫的耐性评价

Evaluation of zinc deficiency tolerance in different kinds of apple rootstocks

为筛选适应缺锌胁迫环境的砧木资源,以山定子、丽江山定子、小金海棠、锡金海棠、新疆野苹果、八棱海棠、平邑甜茶、火焰海棠8种苹果砧木资源为试材,对砧木株高、干物质量、根系构型及锌含量等指标进行测定,利用模糊隶属函数法进行耐缺锌能力综合评价.结果表明:缺锌处理下,丽江山定子、锡金海棠和新疆野苹果均先表现出新生叶小、簇生等缺锌症状,而小金海棠、火焰海棠缺锌症状不明显;缺锌显著降低了苹果砧木株高和地上部锌积累量,而小金海棠的降低幅度最小;缺锌胁迫下小金海棠和山定子叶片锌含量较高,分别为23.2和21.3 mg·kg-1.采用模糊隶属函数法综合评价参试砧木耐缺锌能力:小金海棠最强,火焰海棠次之,山定子、锡金海棠、八棱海棠和平邑甜茶的耐缺锌能力较弱,丽江山定子和新疆野苹果的耐缺锌能力最弱.

The objective of this study was to screen and evaluate the zinc deficiency tolerance among eight apple rootstocks,i. e.,Malus baccata,M. rockii,M. xiaojinensis,M. sikkimensis,M. sieversii,M. robusta,M. hupehensis and Malus ‘Flame＇. The experiment took these 8 kinds of rootstocks as the research materials to observe and analyze the index of the rootstock＇s height,dry biomass,root architecture and zinc concentration,and with help of the fuzzy membership function to work out a comprehensive evaluation on their zinc deficiency tolerance. The result showed that several obvious zinc deficiency symptoms were observed in three kinds of rootstocks（ M. rockii,M.sikkimensis and M. sieversii）,such as dwarfed plant and newborn small leaves,while such symptoms were not obvious in M. xiaojinensis and M. ‘Flame＇. The plant biomass,height and zinc accumulation of aerial part greatly decreased under zinc deficiency stress,while smaller reduction was observed in M. xiaojinensis than in other rootstocks. M. xiaojinensis and M. baccata had higher zinc concentrations in leaves than others. According to the fuzzy membership function and cluster analysis,the resistance of the eight apple rootstocks to zinc deficiency was ranked： M. xiaojinensis was the highest one; M. ‘Flame＇was the second; M. baccata,M. sikkimensis,M. robusta and M. hupehensis were rather weaker; M. rockii and M. sieversii demonstrated the highest sensitivity to zinc deficiency.