转色期喷施尿素对酿酒葡萄生理品质及酵母可同化氮累积的影响

Impact of urea spraying during color change on physiological quality and yeast assimilable nitrogen accumulation in wine grapes

【目的】针对贺兰山东麓葡萄酒产区氮肥施用不合理引发的酿酒葡萄成熟过快、浆果中酵母可同化氮含量不足导致发酵终止等问题,探究在酿酒葡萄转色期,叶面喷施不同浓度尿素对酿酒葡萄光能利用、生理抗性、浆果品质及酵母可同化氮的影响。【方法】通过大田试验和室内分析相结合,以酿酒葡萄品种‘赤霞珠’为试材,采用随机区组设计,在葡萄转色期叶面喷施0‰、1‰、1.5‰、2‰、2.5‰、3‰、3.5‰浓度的尿素3次,测定酿酒葡萄生理、品质及酵母可同化氮等相关指标,并对结果进行方差分析及显著性检验。【结果】在酿酒葡萄转色期,适量的叶面补氮能显著改善酿酒葡萄浆果品质,且随着尿素浓度的增加,酿酒葡萄叶片光合效率、生理及浆果品质等指标均呈先上升后降低的趋势。在2.0‰浓度喷施下,葡萄叶片净光合速率、类胡萝卜素、超氧歧化酶、单宁含量的效果最佳,较对照处理分别显著提高36.10%、38.46%、14.65%和19.51%。而喷施2.5‰浓度能显著提高气孔导度、水分利用率、叶绿素、过氧化氢酶、穗长、粒径、百粒重、可溶性固形物、糖酸比、花色苷、总酚和酵母可同化氮,较对照处理分别提高54.53%、26.32%、13.66%、264.61%、20.99%、44.47%、42.55%、4.50%、3.18%、108.13%、33.71%和54.85%。喷施3.5‰浓度显著提高叶面积、脯氨酸、丙二醛,较对照处理分别提高30.80%、156.21%和48.04%。【结论】在酿酒葡萄转色期叶面喷施2.5‰浓度的尿素能显著增加叶片光合利用效率,增强酿酒葡萄叶片生理抗性,提高浆果品质及酵母可同化氮,改善酿酒葡萄浆果品质,进而为贺兰山东麓葡萄酒产区酿造优质葡萄酒提供优质葡萄原料。

【Objective】The present paper aimed to investigate the effects of foliar spraying of different concentrations of urea on light energy utilization,physiological resistance,berry quality and yeast assimilable nitrogen in wine grapes during the color change of wine grapes in the wine production area of the eastern Helan Mountains.【Method】A combination of field trials and indoor analysis was conducted with the wine grape variety‘Cabernet Sauvignon’as the test material in a randomized block design.Urea was sprayed three times at 0‰,1‰,1.5‰,2‰,2.5‰,3‰and 3.5‰during the color change of grapes,and the related indexes of physiology,quality and yeast assimilable nitrogen of wine grapes were measured,and the results were analyzed by ANOVA and significance test.【Result】During the color change of wine grapes,foliar nitrogen supplementation at appropriate levels significantly improved the berry quality of wine grapes.With the increase of urea concentration,the photosynthetic efficiency,physiology and berry quality of wine grape leaves showed a trend of increasing and then decreasing.The best results for net photosynthetic rate,carotenoids,superoxide dismutase and tannin content of grape leaves were obtained at 2.0‰concentration spray.They were significantly increased by 36.10%,38.46%,14.65%and 19.51%,respectively,compared with the control treatment.Spraying 2.5‰concentration significantly increased stomatal conductance water utilization,chlorophyll,catalase,spike length,grain size,100 grain weight,soluble solids,sugar to acid ratio,anthocyanin,total phenols and yeast assimilable nitrogen by 54.53%,26.32%,13.66%,264.61%,20.99%,44.47%,42.55%,4.50%,3.18%,108.13%,33.71%and 54.85%,respectively,higher than the control treatment.Spraying 3.5‰concentration significantly increased leaf area,proline and malondialdehyde by 30.80%,156.21%and 48.04%,respectively,compared with the control treatment.【Conclusion】A comprehensive analysis showed that foliar spraying of urea at a concentration of 2.5‰during the color change of wine grapes significantly increased the photosynthetic utilization efficiency of leaves,enhanced the physiological resistance of wine grapes leaves,improved berry quality and yeast assimilable nitrogen,and improved the quality of wine grapes berries.In turn,it provided high quality grape raw materials for making high quality wine in the eastern Helan Mountains wine region.