摘要
以"苏州青"和"矮脚黄"2个小白菜品种为试材,采用室内模拟砂培培养法,研究了供钾水平(0.0、2.5、5.0、7.5、10.0mmol·L^(-1))对其根、叶柄和叶片同化物及钾素分配的影响,以期为采用钾高效利用技术提高小白菜产投比的钾营养诊断相关研究奠定基础。结果表明:供钾水平对小白菜生物量的影响随其生育期的延长而增大。其中,"苏州青"的同化物分配对供钾水平的响应较"矮脚黄"相对敏感,其可食部分生物量(地上部生物量、产量)最大时的供钾水平相对低于"矮脚黄",而植株不同部位钾含量最高时的供钾水平却相对高于"矮脚黄"。小白菜植株不同部位钾含量的高低顺序依次为叶柄、叶片和根系,且不同部位钾含量最高时所需要的外源供钾水平及钾在小白菜植株不同部位的分配百分比均表现为叶片>叶柄>根系,说明小白菜植株不同部位对供钾水平的敏感性存在明显差异。适宜的供钾水平可能通过协调同化物在植株不同部位的分配,并维持分配比例的稳定性,达到促进小白菜生长的效果。与正常供钾水平比,供试的2个品种小白菜对过量钾的响应也存在一定的差异:分别通过明显降低"苏州青"的根系钾含量及矮脚黄的根系同化物的分配,而减少了钾在其各自根系中的分配。缺钾通过降低同化物,特别是钾在小白菜叶柄中的分配而明显增加了其向叶片和根系的分配,进而提高了小白菜的根冠比。随着供钾水平的升高,只有叶柄的同化物和钾分配的百分比均有所升高,且以钾分配百分比的升高幅度远大于同化物。综上所述,叶柄钾含量和叶柄钾分配百分比对小白菜钾营养状况存在较好的指示作用。
Two Brassica chinensis cultivars（‘Suzhouqing＇and‘Aijiaohuang＇）were used as materials,effect of potassium（K）rates（0.0,2.5,5.0,7.5,10.0mmol·L^-1）on assimilate and K distribution was studied in different parts of two Brassica chinensis cultivars by using sand culture method.The objective of the study were to reveal the relationship between symptom and diagnose of potassium nutrition,and to improve benefit-cost ratios with potassium efficient utilization technology.The results showed that biomass response of Brassica chinensis cultivars to K rate increased with the growing period.Assimilate distribution of Brassica chinensis cultivars ‘Suzhouqing＇was more sensitive to K rates than that of Brassica chinensis cultivars‘Aijiaohuang＇,since K rate for the maximum yield of‘Aijiaohuang＇was higher than that of‘Suzhouqing＇.However,K rate for the maximum K content in different parts of‘Suzhouqing＇was higher than that of‘Aijiaohuang＇.K content of the two Brassica chinensis cultivars followed the ascending order,petio〉lesleaves〉roots.Moreover,both of K rate for the maximum K content in different parts of the two Brassica chinensis cultivars and the K distribution percentage followed the ascending order,leaves〉petioles〉roots,which suggested that sensitivity to K rate was significantly different among the different parts of the Brassica chinensis cultivars.Optimum K rate could enhance growth of the two Brassica chinensis cultivars by harmonizing assimilates distribution in different parts of the plants and maintaining the stability of the assimilates distribution ratio.Excessive K reduced K distribute to the roots,however,the reduction in‘Suzhouqing＇was mainly due to the reduction in root K content,and in‘Aijiaohuang＇was mainly due to the reduction in roots assimilate distribute,respectively,as compared with the normal K rate（5.0mmol· L^（-1））.K deficiency reduced assimilate and K distribute percentage in petiole and significantly increased the percentages in lea
出处
《北方园艺》
CAS
北大核心
2017年第16期121-127,共7页
Northern Horticulture
基金
国家公益行业资助项目(201203013)
安徽省省级质量工程资助项目(2012jyxm416)
安徽科技学院第十批大学生创新课题资助项目(13XSZ80)
关键词
钾
小白菜
同化物
营养诊断
potassium
Brassica chinensis
assimilate
nutrition diagnosis
