单氰胺对休眠及其解除中葡萄多酚和多酚代谢酶及不同部位单体酚含量的影响

Influence of Cyanamide on Polyphenol,Polyphenol Oxidase and Free Phenol in Different Places of Grapevine during Dormancy Induction and Release

研究单氰胺处理下葡萄休眠冬芽总酚含量和PPO、PAL活性的变化,并利用高效液相色谱切换波长法对休眠打破过程中葡萄冬芽和1a生枝条韧皮部和木质部中6种单体酚的变化进行考察。结果表明,葡萄休眠过程中,随着低温的积累,PPO、PAL活性和酚类物质总量均增加,PAL活性和总酚量在休眠解除过程中均降低且变化趋势基本一致,但降幅有限,从整体上看PPO在萌芽后仍旧维持较高活性。单氰胺处理后与对照差异不大。在黑比诺葡萄休眠打破过程中,韧皮部中除白藜芦醇外,没食子酸、原儿茶酸、儿茶素、表儿茶素、没食子酸酯均呈上升趋势;木质部中的没食子酸、原儿茶酸和表儿茶素呈上升趋势,白藜芦醇呈下降趋势,儿茶素呈"W"型,表儿茶素、没食子酸酯无明显变化规律;冬芽中没食子酸和儿茶素的变化呈上升趋势,原儿茶酸、表儿茶素、没食子酸酯、白藜芦醇均呈下降趋势,且其中的原儿茶酸、表儿茶素和没食子酸酯在临近萌芽的一段时间内含量基本不变,萌芽后含量迅速下降。初步判定没食子酸可能对休眠解除起促进作用,白藜芦醇可能对休眠解除起抑制作用。

A research was conducted to investigate the regularity variation of total phenolics,activities of PPO and PAL in dormant grapevine buds. At the same time, six mono-phenolics were detected with switching detection wavelength in HPLC for dormant buds, phloem and xylem of one-year-old grape- vine canes treated with cyananmide. It indicated that during the early dormancy stage,PPO, PAL ac- tivities and total phenolic content were increasing with the accumulation of low temperature,PAL ac- tivity and total phenolic slightly decreased and showed a similar trend during the dormancy release. On the whole,PPO activity was kept at a high level in this stage. No different effects were detected on the treatment with cyanamide. During the Pinot Noirs whole dormancy stage, except for trans-resvera- trol, the contents of gallic acid, protocatechuic acid, （＋）-catechin, epicatechin, （-）-epicatechin-3-O- gallate showed a downward trend in phloem; the contents of gallic acid, protocatechuic acid, epicate-chin showed an upward trend in xylem and trans-resveratrol showed a downward trend, （＋）-catechin showed a ＂W-shape＂ trend, （-）-epicatechin-3-O-gallate showed no obvious change;in winter bud, the contents of gallic acid, （q-）-catechin showed an upward trend, protocatechuic acid, epicatechin, （ -- ）- epicatechin-3-O-gallate and trans-resveratrol showed a downward trend, but protocatechuic acid, epi- catechin, （-）-epicatechin-3-O-gallate （-）-epicatechin showed no change before bud break and dropped dramatically after budding. It was inferred gallic acid might promote the dormancy releasing, while trans-resveratrol might inhibit the dormancy releasing.