叶面喷施不同浓度镁肥对酿酒葡萄光合特性、产量及浆果品质的影响

Effects of foliar application of magnesium fertilizer with different concentrations on photosynthetic characteristics, yield and berry quality of wine grapes

为筛选出适宜酿酒葡萄的叶面喷施镁肥浓度,为酿酒葡萄科学管理提供技术支撑和理论指导,以7年生酿酒葡萄‘赤霞珠’(Cabernet Sauvignon)为研究对象,在常规施肥的基础上,分别设置叶面喷施镁肥(MgSO_(4)·7H_(2)O)CK(0.00%)、F1(0.09%)、F2(0.18%)、F3(0.27%)、F4(0.36%)和F5(0.45%)6个处理,进行田间试验,探讨贺兰山东麓碱性土壤条件下,不同叶面施镁浓度对酿酒葡萄赤霞珠叶片光合特性、果实品质以及产量的影响。结果显示:叶面喷施0.27%镁肥效果最为显著,与CK相比,叶绿素a(Chl a)、叶绿素b(Chl b)和叶绿素a+b(Chl a+b)分别提高28.26%、42.81%和32.49%;净光合速率、蒸腾速率和气孔导度分别提高36.72%、65.58%和100.82%;总酚、单宁、花色苷、可滴定酸及产量分别提高11.22%、8.08%、29.60%、11.69%和8.17%。通过相关分析发现,酿酒葡萄产量与Chl b、净光合速率、蒸腾速率、气孔导度呈极显著正相关,与Chl a、花色苷呈显著正相关,与胞间CO2浓度呈显著负相关。通过主成分分析,得出在常规施肥基础上,叶面喷施0.27%镁肥对提高赤霞珠叶片光合特性和果实产量及平衡糖酸比改善浆果品质效果最佳。

In order to screen out a suitable concentration of magnesium applied to wine grape leaves so as to provide technical support and theoretical guidance for the scientific management of wine grapes, the effects of magnesium fertilizer application on the chlorophyll content, photosynthetic characteristics, quality and yield of Cabernet Sauvignon under alkaline soil conditions in the eastern foothills of Helan Mountain were explored. Field trials were carried out with 7-year-old wine grapes ’Cabernet Sauvignon’ as the materials, and six treatments, including CK(0%), F1(0.09%), F2(0.18%), F3(0.27%), F4(0.36%)and F5(0.45%) magnesium fertilizer(MgSO_(4)·7 H_(2)O), were applied on the foliage respectively on the basis of conventional fertilization. The results showed that the effect was most significant when the concentration of foliar magnesium applied was 0.27%, as compared with CK, the contents of chlorophyll a, chlorophyll b, chlorophyll(a+b) increased by 28.26%, 42.81% and 32.49%, respectively;the net photosynthetic rate, transpiration rate and stomatal conductance increased by 36.72%, 65.58% and 100.82%, correspondingly;the total phenol, tannin, anthocyanin, titratable acid and yield increased by 11.22%, 8.08%, 29.60%, 11.69% and 8.17%, respectively. In conclusion, through correlation analysis, it was found that the yield of wine grapes was extremely significantly positively correlated with chlorophyll b, net photosynthetic rate, transpiration rate and stomatal conductance, and it was also significantly positively correlated with chlorophyll a and anthocyanin, but it was significantly negatively correlated with intercellular CO2 concentration. Through principal component analysis,it was concluded that the foliar magnesium fertilizer spraying at the concentration of 0.27% had the best effect on improving the photosynthetic characteristics of Cabernet Sauvignon leaves and fruit yield, balancing the sugar-acid ratio and improving the berry quality on the basis of conventional fertilization.