钾肥种类及用量对低温胁迫下苜蓿根颈糖类物质含量及抗寒性的影响  

Effects of potash fertilizer types and rates on alfalfa root crown saccharides content and cold resistance under low temperature stress

作　　者：孙明雪 张玉霞[1] 夏全超 王显国[2] 张庆昕[1] 刘庭玉[1] 张永亮[1] SUN Mingxue;ZHANG Yuxia;XIA Quanchao;WANG Xianguo;ZHANG Qingxin;LIU Tingyu;ZHANG Yongliang(College of Agriculture,Inner Mongolia Minzu University,Inner Mongolia Autonomous Region Feedstuff Engineering Technology Research Center,Tongliao,Inner Mongolia 028041,China;College of Grassland Science and Technology,China Agricultural University,Beijing 028000,China)

机构地区：[1]内蒙古民族大学农学院,内蒙古自治区饲用作物工程技术研究中心,内蒙古通辽028041 [2]中国农业大学草业科学与技术学院,北京028000

出　　处：《干旱地区农业研究》2022年第5期62-70,共9页Agricultural Research in the Arid Areas

基　　金：内蒙古自治区自然科学研究基金(2020MS03081);国家自然科学基金(31960352);内蒙古自治区科技计划项目(2021GG0109)。

摘　　要：为探讨钾肥种类及用量对苜蓿越冬器官抗寒性的影响及根颈糖类保护物质代谢的生理机制,本研究对‘北极熊’紫花苜蓿(M.sativa‘Gibraltar’)施用KCl、K_(2)SO_(4)和KH_(2)PO_(4)3种钾肥,设置100、200、300 kg·hm^(-2)K_(2)O(分别用K、K和K表示)3个施用量,以不施钾肥为对照(CK),于封冻前期挖取苜蓿越冬器官模拟低温冷冻胁迫处理(4℃、-10℃、-20℃和-30℃),测定根颈活力、可溶性糖、蔗糖、果糖和淀粉含量。结果表明,随着低温冷冻胁迫温度的降低,KCl、K_(2)SO_(4)和KH_(2)PO_(4)处理的苜蓿根颈活力和淀粉含量表现为持续降低的变化趋势,在-30℃下达到最小值,且与4℃处理呈显著差异(P<0.05),分别较4℃处理降低了86.25%~91.59%和45.47%~66.07%;可溶性糖、蔗糖和果糖含量则表现为先升高后降低的变化趋势,且均在-20℃下达到最大值,分别达到431.00~513.93 mg·g、235.23~329.05 mg·g和185.75~243.79μg·g^(-1)。随着钾肥施用量的增加,KCl、K_(2)SO_(4)和KH_(2)PO_(4)处理的苜蓿根颈活力、可溶性糖、蔗糖、果糖和淀粉含量均表现为先升高后降低的趋势;且在不同低温胁迫处理下以K_(2)SO_(4)处理效果最明显,并且在施用量为200 kg·hm^(-2)K_(2)O时,苜蓿根颈活力、可溶性糖、蔗糖、果糖和淀粉含量均与CK差异显著(P<0.05),分别较CK增长了56.03%~197.26%、16.38%~48.77%、24.13%~46.22%、30.53%~59.95%和35.73%~67.87%。因此,科尔沁沙地建植苜蓿宜施用K_(2)SO_(4)种类钾肥,建议施用量为200 kg·hm^(-2)K_(2)O,更有利于提高苜蓿越冬器官的抗寒性。This study applied 3 types of KCl,K_(2)SO_(4)and KH_(2)PO_(4)potash fertilizers to alfalfa(M.sativa‘Gibraltar’)to explore the effects of potash fertilizer types and dosages on cold resistance of alfalfa overwintering organs and the physiological mechanism of carbohydrate protection.Three application rates including 100 kg·hm^(-2)K_(2)O,200 kg·hm^(-2)K_(2)O and 300 kg·hm^(-2)K_(2)O(indicated by K,Kand K,respectively),and the control(CK)group without potash fertilizer were used.The overwintering organs of alfalfa were excavated in the pre-freezing period to simulate low temperature freezing stress(4℃,-10℃,-20℃and-30℃),and the root crown vitality,soluble sugar,sucrose,fructose and starch content were measured.With the decrease of low temperature and freezing stress,the root crown vitality and starch content of alfalfa treated with KCl,K_(2)SO_(4)and KH_(2)PO_(4)showed a continuous decreasing trend,with minimum value reaching at-30℃.The root crown activity and starch content of alfalfa treated at 4℃were significantly different,which were 86.25%~91.59%and 45.47%~66.07%lower than those treated at 4℃,respectively.The content of soluble sugar,sucrose and fructose showed a trend of first increasing and then decreasing,and all reached the maximum at-20℃,and they were 431.00~513.93 mg·g,235.23~329.05 mg·gand 185.75~243.79μg·g^(-1),respectively.With the increase of the amount of potash fertilizer,the root crown vitality,soluble sugar,sucrose,fructose,and starch content of alfalfa treated with 3 potash fertilizers of KCl,K_(2)SO_(4),and KH_(2)PO_(4)showed a trend of first increasing and then decreasing,and under different low temperature stress treatments,the effect of K_(2)SO_(4)treatment on alfalfa root crown vitality,soluble sugar,sucrose,fructose,and starch content was the most obvious.When the application rate was 200 kg·hm^(-2)K_(2)O,the alfalfa root crown vitality,soluble sugar,sucrose,fructose,and starch content were significantly different from CK(P<0.05),and compared with CK,it increased

关 键 词：苜蓿 根颈 钾肥种类 糖类物质 抗寒性 

分 类 号：S551.7[农业科学—作物学] S365[生物学—植物学] Q945.78