关键词：
葡萄;叶面喷肥;钾肥;钾吸收基因;基因表达
摘 要：
【目的】叶面喷施钾肥可以快速、高效地为葡萄补充钾营养,促进葡萄的高产和优质,已经被广泛应用于葡萄生产中。本实验通过对葡萄叶面喷施不同种类及浓度钾肥,测定葡萄叶片和果实等生理指标变化,以及钾吸收相关基因的表达变化,从生理和基因水平上评价这些钾肥的喷施效果,为葡萄生产中钾肥的施用提供一定指导。【方法】本实验以‘夏黑’葡萄为试材,选择两个葡萄生长关键时期盛花期和果实膨大期分别对葡萄叶片喷施0.2%、0.5%和0.8%三种浓度的K_2SO_4、K_2CO_3、K_2SO_4·2MgSO_4和KCl。然后对葡萄叶片和新梢的生长率,坐果率,叶绿素含量,单粒重,可溶性固形物等生理指标进行统计分析,并利用荧光定量PCR技术分析4个钾吸收相关基因Vv HAK13、Vv KEA2、Vv SIRK和Vv SORK的表达情况。【结果】叶面喷施4种钾肥后,葡萄叶片和新梢的生长率,坐果率,叶绿素含量,单粒重,可溶性固形物等各项生理指标均有不同程度的提升。钾肥种类不同,最适喷施浓度不同,同种钾肥在葡萄盛花期和果实膨大期的最适喷施浓度也有所不同,四种钾肥在果实膨大期的最适喷施浓度普遍高于盛花期。四个钾吸收相关基因在喷施不同种类及浓度钾肥后也表现出不同的表达模式,总体来讲Vv KEA2、Vv SIRK、Vv SORK的表达上调,而Vv HAK13的表达下调。果实膨大期,需喷施较高浓度的钾肥,钾吸收相关基因才表现出较强烈的响应,而在盛花期则只需喷施较低浓度的钾肥。综合生理指标和基因表达两方面结果,得出4种钾肥效果依次为K_2SO_4·2MgSO_4>K_2SO_4>K_2CO_3>KCl。盛花期K_2SO_4和K_2CO_3的最适喷施浓度为0.5%,K_2SO_4·2MgSO_4和KCl的最适喷施浓度为0.2%;果实膨大期K_2SO_4、K_2SO_4·2Mg SO_4和KCl的最适喷施浓度为0.5%,K_2CO_3的最适喷施浓度为0.8%。【结论】葡萄叶面喷施钾肥可以有效促进葡萄叶片和果实的生长发育,四种钾肥的效果依此为:K_2SO_4·2MgSO_4>K_2SO_4>K_2CO_3>KCl。盛花期K_2SO_4和K_2CO_3的最适喷施浓度为0.5%,K_2SO_4·2MgSO_4和KCl的最适喷施浓度为0.2%;果实膨大期K_2SO_4、K_2SO_4·2MgSO_4和KCl的最适喷施浓度为0.5%,K_2CO_3的最适喷施浓度为0.8%。适宜的喷施浓度可以有效提高钾吸收相关基因的表达,是其提高钾吸收利用的机理之一。
译 名：
Effectiveness and concentration of foliar-application of potassium fertilizers on grapevine evaluated by expression of potassium uptake related genes
作 者：
ZHANG Cheng;JIA Hai-feng;WANG Jian;JIU Song-tao;WANG Meng-qi;College of Horticulture,Nanjing Agricultural University;
关键词：
grapevine;;foliar application;;potassium fertilizer;;potassium uptake gene;;gene expression
摘 要：
【Objectives】Foliar application of potassium( K) fertilizer has been widely adopted in grape production as an effective K supplement measurement. In this study,four types of K compounds were sprayed in three different concentrations at full-blooming stage and berry expansion stage of grapes,to study the responses of the physiological traits and the expression variation of K uptake related genes,and to evaluate the effectiveness of these K fertilizers and concentrations for practical grape production. 【Methods 】 Grapevine cv. ‘Summer Black '( hybrid of V.vinifera × V. labrusca) vines were used as experimental material,0. 2%,0. 5% and 0. 8% solutions of K_2SO_4,K_2CO_3,K_2SO_4·2MgSO_4 and KCl were sprayed at the full-bloom stage and berry expansion stage. The growth rate of leaves and shoots,fruit setting rate,leaf chlorophyll content,single berry weight and total soluble solid content were measured,and the expression variation of the four K uptake related genes,Vv HAK13,Vv KEA2,Vv SIRK and Vv SORK were analyzed using real-time quantitative PCR. 【Results】All the foliar applications of K fertilizers are effective to improve the physiological indexes to different extents,and K_2SO_4·2MgSO_4 shows the best result,following are K_2SO_4,K_2CO_3,KCl. The optimum spraying concentrations are 0. 2%- 0. 5% at full blooming stage and 0. 5%- 0. 8% at berry expansion stage. Relatively higher K fertilizer concentration is required at berry expansion stage than at full blooming stage. The four K uptake related genes show different expression responses to the treatments. In general,the expression of Vv KEA2,Vv SIRK and Vv SORK are up-regulated,but that of Vv HAK13down-regulated. In berry expansion stage,the four K uptake related genes show more remarkable responses to spraying concentrations of 0. 5%- 0. 8%,but do the same to spraying concentration of 0. 2%- 0. 5% at fullbloom stage.【Conclusions】Spraying K fertilizer is effective to up-regulate the expression of K- related genes,which are reflected by the increased physiological indexes. Among the four tested fertilizers,K_2SO_4·2MgSO_4 shows the best result,following are K_2SO_4,K_2CO_3 and KCl. Spraying concentration of 0. 2%- 0. 5% is recommended in full-bloom stage and 0. 5%- 0. 8% in the berry expansion stage of grape.
