索海翠 王丽 李成晨 刘计涛 安康 李小波

摘  要：為明确锌对马铃薯叶片光合特性及超微结构的影响，以马铃薯品种‘粤引85-38为试验材料，在出苗后第40 天，叶面喷施5个不同浓度ZnSO47H2O溶液[0（T0）、3.5 mmol/L（T1）、7.0 mmol/L（T2）、14.0 mmol/L（T3）和28.0 mmol/L（T4）]。结果显示，与缺锌处理T0相比较，较低浓度T1和T2处理显著提高了马铃薯叶片的SPAD值和净光合速率（Pn），显著增加了地上部鲜重、地上部干重、薯块鲜重及叶片和薯块锌含量;但当处理浓度达到T4时，马铃薯叶片SPAD值和Pn显著降低，各指标分别与T0处理差异不显著，而最大荧光产量Fm，PSⅡ最大光合量子产量Fv/Fm，非光化学淬灭系数qP和化学淬灭系数NPQ则显著低于T0处理，但叶片和薯块锌含量则显著升高。进一步对叶片显微和超微结构研究显示，T2处理下马铃薯叶片栅栏组织和海绵组织排列整齐，叶绿体形态结构完好，而T0和T4处理降低了叶片表皮厚度，增加了细胞间隙。T0处理下淀粉粒增多，叶绿体膨胀短缩，基粒片层模糊不清;T4处理下细胞凹陷，叶绿体形状改变。以上结果表明，在本研究中，T1～T2处理为较为适宜马铃薯生长的锌浓度。本研究从生理上揭示了锌缺失和过量对马铃薯光合作用和生长发育的影响，为马铃薯田间叶面喷施锌肥提供一定的理论参考。

关键词：马铃薯;叶面施锌;光合作用;超微结构

中图分类号：S532    文献标识码：A

Effects of Leaf-Spraying Zinc Treatment on Photosynthetic Characteristics， Ultrastructure of Potato Leaves and Yield

SUO Haicui， WANG Li， LI Chengchen， LIU Jitao， AN Kang， LI Xiaobo*

Crops Research Institute， Guangdong Academy of Agricultural Sciences / Guangdong Province Key Laboratory of Crop Genetic Improvement， Guangzhou， Guangdong 510640， China

Abstract： In order to clarify the effects of zinc on the photosynthetic characteristics and ultrastructure of potato leaves， potato variety ‘Yueyin 85-38 was used. Five ZnSO47H2O solutions with different concentrations [0 （T0）， 3.5 mmol/L（T1）， 7.0 mmol/L（T2）， 14.0 mmol/L（T3） and 28.0 mmol/L（T4）] were sprayed on the leaves at the 40th day after seedling emergence. Compared with T0 treatment， low concentration treatments T1 and T2 significantly increased the leaf SPAD value and net photosynthetic rate （Pn）， and the aboveground fresh and dry weight， fresh tuber weight as well as leaf and tuber zinc content were also significantly increased. When the spraying concentration reached T4， however， the potato leaf SPAD and Pn were significantly reduced， which was not significantly different with that of T0， and the maximum fluorescence yield Fm， PS Ⅱ maximum photosynthetic quantum yield（Fv/Fm）， non photochemical quenching coefficient （qP） and chemical quenching coefficient （NPQ） were significantly lower than that of T0， while the leaf and tuber zinc content were increased significantly. Leaf microstructure and ultrastructure showed that under T2 treatment， palisade tissue and sponge tissue of potato leaves were neatly arranged， chloroplast morphology and structure were intact. While under T0 and T4 treatments， the uniformity of palisade tissue was decreased， and intercellular was increased. Under T0 treatment， starch granules increased， the chloroplast expanded and shrank， the granule lamella was obscure. Under T4 treatment， cell and chloroplast membrane structure was damaged. The zinc concentration of T1 and T2 was   suitable for potato growth. The study revealed the physiological effects of zinc deficiency and excess on the photosynthesis of potato， and could provide theoretical reference for the application of zinc fertilizer on potato in the field.

Keywords： potato （solanum tuberosum L.）; leaf-spraying zinc; photosynthesis; ultrastructure

DOI： 10.3969/j.issn.1000-2561.2021.07.020

锌是植物体所必需的微量营养元素之一，作为六大类功能酶中的辅助因子成分，能够调节酶的活性，广泛参与植物体多种生长发育代谢过程，包括蛋白质、核酸、碳水化合物和磷脂的合成与代谢、植物生长激素的调控、应对逆境胁迫以及光合作用等[1-3]。……