SA、MeJA和ACC处理对甘蓝型油菜叶角质层蜡质组分、结构及渗透性的影响

摘要

Cuticular waxes are related to plant adaptation to environment stress. In the current study,Brassica napus cv. Zhong-shuang 11 grown in the soil treated with adding solutions of SA (200μmol L–1), MeJA (100μmol L–1), and ACC (200μmol L–1) wax, were sampled at the five-leaf stage to clarify the effects of SA, MeJA and ETH on adjusting plant cuticular wax deposition. The leaves were used to analyze the amounts of total cuticular wax and wax constituents, wax crystal structure, and cuticular per-meability. The amounts ofn-alkanes, secondary alcohols, ketones, aldehydes and total cuticular waxes increased significantly when compared with the control at seven days after MeJA treatment, whereas the amounts of all wax constituents and total cu-ticular waxes significantly decreased at 14 days after MeJA treatment. The application of SA and ACC had no significant influ-ence on cuticular wax deposition at 7 and 14 days after treatments, except for an amount reduction of primary alcohol, aldehyde and unknown constituents for SA treatment at 14 days after treatment. At 21 days after SA, MeJA, and ACC application, the amounts of total cuticular wax,n-alkanes, ketones and aldehyde significantly increased. C29 n-alkane, C29 ketone, and C30 al-dehyde were the main cuticular wax constituents induced by SA, MeJA, and ACC application, implying thatn-alkane, ketone and aldehyde might be related to the resistance to stresses induced by these signal molecules. Scan electric microscope analysis in-dicted that the rod-shape structure of cuticular wax in leaf surface reduced and some rods melted under SA treatment. MeJA and ACC application increased the distribution density of wax crystalloids. The cuticular wax deposition and crystal structure altera- tion reduced the cuticular permeability and delayed the leaf water loss. The specific increase of C29n-alkane might be the main reason for reducing leaf water loss inB. napus.%角质层蜡质与植物适应逆境胁迫有关。本研究以甘蓝型油菜中双11为试材，在五叶期分别对其进行200μmol L–1水杨酸(SA)溶液、1-氨基环丙烷-1-羧酸(ACC)溶液以及100μmol L–1茉莉酸甲酯(MeJA)溶液浇灌处理，分析油菜叶角质层蜡质组分含量、结构以及角质层渗透性的变化。结果表明， MeJA处理7 d后，烷类、二级醇类、酮类、醛类含量以及蜡质总量与对照相比均显著增加，而处理14 d后，所有蜡质组分含量及蜡质总量与对照相比均显著减少； SA与ACC处理早期对叶片蜡质沉积无显著影响(SA处理14 d后，一级醇类、醛类及未知组分含量显著减少)。SA、MeJA和ACC处理21 d后均显著诱导油菜叶片角质层蜡质的沉积，蜡质组分中烷类、酮类、醛类显著增加，其中C29烷、C29酮、C30醛是被SA、MeJA和ACC诱导的主要蜡质组分，暗示烷类、酮类、醛类可能与这些信号分子介导的抗(耐)性反应密切相关。扫描电镜结果显示， SA处理减少叶表皮蜡质杆状结构，且部分区域熔融； MeJA与ACC处理增加油菜叶表皮蜡质的晶体结构密度。角质层蜡质的沉积与结构变化降低角质层渗透性，减缓叶片的水分散失，其中 C29烷的特异性增加可能是造成叶片失水率降低的主要原因。