摘要
通过盆栽试验研究了不同供钾水平下水稻各叶位的含钾量变化。结果表明,水稻含钾量随生育期的推进逐渐下降,下降幅度达69%～75%。水稻含钾量与生育期和土壤供钾水平有关:分蘖期不同叶位的鞘、叶含钾量由上至下大幅下降,鞘与叶的含量钾比值均大于1,且比值随叶片含钾量的增加而上升。拔节期钾素水平由低至高,叶位间鞘、叶含钾量由上至下降低的趋势减弱;鞘与叶含钾量比值为0.26～1.49,且随叶片含钾量的增加而增加。齐穗期,低钾水平下,叶位间鞘、叶含钾量由上至下降低,高钾水平则相反;鞘叶含钾量比值为0.36～1.33。成熟期,秸秆的含钾量范围为2.8～22.9 g/kg,随钾素水平增加而增加;籽粒的含钾量约为5.0 g/kg。综合不同时期含钾量变化规律可以看出,水稻分蘖期上部叶是钾素优先积累的部位,而叶鞘更是钾奢侈吸收储存的部位;齐穗期以后,钾奢侈吸收主要是积累到了中下部叶和叶鞘中。由于水稻植株钾含量因不同生育期、不同部位而变化很大,根据植株钾含量来进行营养诊断需要考虑取样时期、取样部位,而鞘、叶钾含量比值可能有较好的指示作用。
Pot culture experiment was carried out to investigate the effect of soil K level on K contents in various parts of rice plants. The results showed that K content of rice plant reduced gradually during whole growth period. As compared with tillering stage, K content of rice plant decreased by about 69%-75% at maturity stage. Both growing stage and soil K level were the key factors affecting K content office plant. At tillefing stage, K content of leaf and sheath reduced significantly from top leaf to lower leaves. The ratios of the sheath K content to the corresponding leaf K content were all higher than 1, and the ratios increased accordingly as leaf K content increased. At jointing stage, the similar trend of K content among leaves was also observed as compared with that of tillefing stage, but the decrement of K content from top leaf to lower leaves became smaller, and K content ratios of sheath to leaf also reduced, which ranged from 0.26 to 1.49. At full heading stage, K content of upper leave and sheaths was higher than that of lower leave or sheaths when K supply in soil was lower, but K content of lower leave was higher that that of upper leaves when soil K supply was higher. At maturity stage, K content office stalk ranged from 2.8 to 22.9 g/kg as the soil K supply increased, while K content office seeds remained about 5.0 g/kg. The above results indicated that rice K was preferentially accumulated in upper leaves at tillering stage, and the sheath is the reserve for luxury K uptake, while the lower leave and sheaths were the reserve for luxury K uptake after full heading stage. As rice K content varied greatly among different growing stages and different organs, it＇s important to choose the right stage and right organ for rice K status diagnoses. The ratios of sheath K content to corresponding leaf K content is possible a good index for rice K status diagnoses.
出处
《土壤》
CAS
CSCD
北大核心
2013年第3期489-494,共6页
Soils
基金
农业部行业专项项目(201203013)
国际植物营养研究所中国项目(Nanjing-12)
国家自然科学基金项目(40971176)资助
关键词
水稻
钾素水平
含钾量
鞘叶比
Rice, Soil K level, K content, Ratio of sheath to leaf
作者简介
陈智慧（1987-），女，重庆潼南人，硕士研究生，主要研究方向为植物钾营养。E-mail：zhchen@issas．ac．cn
通讯作者（jmzhou@issas.ac．cn）
