秋冬季补光处理对‘阳光玫瑰’葡萄叶片及冬果发育的影响

Effect of Artificial Supplementary Lighting During Autumn and Winter on Leaf Senescence and Development of Winter Fruits of‘Shine Muscat’Grape

【目的】近年广东葡萄产业兴起,成为可进行一年两收的高效益特色产区。秋冬季的短日照和低温诱导系统性叶片衰老,不利于冬季葡萄果实发育和品质形成。探索人工补光对冬季葡萄叶片衰老和果实发育的影响,为维持冬季叶片功能、保障果实发育提供技术依据。【方法】以8年生‘5BB’砧‘阳光玫瑰’为试材。从10月中旬开始,以3μmol/m^(2)·s红光+蓝光(5∶1)的LED灯带为‘阳光玫瑰’果穗节位附近叶片施加人工光照,补光时间为每天18∶00—24∶00,直至果实成熟,观测记录果穗节位叶片的叶绿素指数(SPAD值)、光合参数及浆果纵横径,分析果实成熟时单果重、穗重及可溶性固形物(TSS)含量。【结果】12月中旬(补光处理6周),对照株果穗节位叶片逐渐黄化、SPAD值降低,而人工光照植株同节位叶片SPAD降幅较小;补光处理后10周,植株各节位叶片SPAD均显著高于对照,而落叶率均显著低于对照,表明补光处理可以抑制冬季葡萄叶片系统性衰老;11月中旬至12月底(处理后4~8周),补光处理与对照株净光合速率(Pn)均显著降低,但补光植株Pn降幅较低。葡萄叶片Pn与气孔导度(Gs)无显著相关性,但与胞间CO_(2)浓度(Ci)呈极显著负相关,说明冬季叶片衰老光合能力减弱主要由非气孔限制导致,而补光处理可降低气孔和非气孔对光合作用的限制。采收时,补光处理单果重(10.8 g)显著高于对照(8.8 g),果实横径增大,单穗重也略有提高,但果实TSS含量(15.0%)显著低于对照(16.7%)。【结论】补光处理可显著推迟冬季葡萄叶片系统性衰老,促进浆果生长。在广州或类似气候的地区生产冬季葡萄,可实施LED人工补光来延缓叶片衰老,但仍需要采取配套措施促进果实TSS的积累。

【Objective】In recent years,grape industry has developed rapidly in Guangdong Province,which has been a high-profit grape production region where two crops of grape berry can be harvested in a year.However,the short day photoperiod and chilling temperatures in autumn and winter induce systematic leaf senescence,which is unfavorable for over-winter berry development and quality formation in grape.In the study,the effect of artificial supplementary lighting on leaf senescence and berry development in‘Shine Muscat’grape were explored,with an aim to provide technical basis for maintaining leaf function and berry development in winter.【Method】From mid-October,8-year-old‘Shine Muscat’plants on rootstock of‘5BB’were treated with 3μmol/m^(2)·s red and blue LED light(5∶1)belts,which were placed above the leaves at the fruit cluster node.Light supplementary was carried out from 18:00 to 24:00 until the berries became mature.Changes in chlorophyll index(SPAD value),photosynthetic parameters(Pn)of the leaves at the fruit cluster node and horizontal and vertical diameters of berries were traced,and single berry weight,cluster weight and total soluble solid(TSS)content were collected at mature period.【Result】After 6 weeks of supplementary lighting treatment,leaves at the cluster node in the control plants became yellowing with decreasing SPAD value.While artificial lighting treatment was effective to suppress leaf chlorosis in winter,with significantly lower SPAD decreasing range.After 10 weeks of treatment,leaves at various nodes in supplementary lighting treatment were higher than those at corresponding nodes in the control plants,suggesting that artificial lighting suppressed systematic leaf senescence in winter.The Pn of both lighting treatment and the control plants decreased dramatically from mid-November to late December.However,the decreasing range of Pn was smaller in the lighting treatment.Pn had no significant correlation with stomatal conductance(Gs),but was extremely negatively correlated to mesophyll CO2 concentration(Ci),indicating the reduction of Pn during leaf senescence in winter was mainly caused by non-stomatal limitation.Supplementary lighting treatment maintained Pn via overcoming both stomatal and non-stomatal limitations.the supplementary lighting treatment,significantly increased single berry weight(10.8 g VS 8.8 g),promoted berry horizontal diameter,slightly increased single cluster weight,but significantly reduced total soluble solids(15.0%VS 16.7%).【Conclusion】The results show that supplementary lighting treatment is effective to delay systematic leaf senescence in winter and promote berry growth.It is recommended to use supplementary LED lighting during over-winter grape cultivation in Guangzhou or in regions with similar climate.However,measures should be taken to promote TSS accumulation in the berry.