不同基因型马铃薯钾素吸收与利用效率的差异

Variation in Potassium Uptake and Utilization Efficiency of Different Potato Varieties

马铃薯是典型的喜钾作物,钾肥施用量对于马铃薯产量具有较大影响,钾高效品种的利用不仅可减少钾肥的用量,还可提高肥料的利用效率从而减少农田生态环境的污染。为此,研究采用二因素裂区试验设计,设低钾水平(75 kg/hm^(2))和高钾水平(300 kg/hm^(2)),选用20份西南地区代表性马铃薯品种(系)为材料,对其开展了钾素吸收和利用效率研究,并对其进行了聚类分析。结果表明,参试品种(系)在两个钾素水平下钾素吸收和利用效率的相关参数存在显著差异;钾素吸收效率在低钾水平下与植株含钾量呈极显著正相关,在高钾水平下与块茎含钾量呈显著正相关;钾素利用效率在低钾水平下与植株含钾量呈极显著负相关(r_(K75)=-0.523^(**));基于钾素营养效率可将20个马铃薯品种分为4类,其中双高效型代表性品种(系)有‘黔芋6号’和‘378711.7’,双低效型有‘08CA0710’和‘09307-830’,高钾高效型有‘米拉’‘中薯19’,低钾高效型有‘华渝5号’‘郑薯5号’。两钾素水平下的单株块茎产量的变异系数较大,可以作为评价钾素利用效率的首选指标。

Potato is one of the potassium loving crops and the potassium is essential to the development of potato yield.Highly efficient utilization of potassium for potato not only decreases the consumption of potassium fertilizer,but also lift the fertilizer use efficiency and protect the agricultural eco-system.The split plot design was employed in the experiment with two potassium nutrition levels(75 and 300 kg/ha)and 20 potato varieties(lines)to study their potassium uptake and utilization efficiency and classify them.The indicators related to potassium uptake and utilization efficiency of potato varieties were significantly different at two potassium levels.Potassium uptake efficiency was highly significantly positively correlated with plant potassium content at low potassium level,and significantly positively correlated with tuber potassium content at high potassium level.The potassium utilization efficiency was highly significantly negatively correlated with plant potassium content at low potassium level(r_(K75)=-0.523^(**)).Based on the potassium nutrient efficiency of potato,20 varieties(lines)were classified into four types.'Qianyu 6'and'378711.7'were the representative double-efficient varieties,'08CA0710'and'09307-830'were the double-inefficient varieties,'Mira'and'Zhongshu 19'belonged to the high-potassium-efficient type,and'Huayu 5'and'Zhengshu 5'belonged to the low-potassium-efficient type.The coefficient of variation of tuber yield per plant under two potassium levels was large,which could be used as the preferred index to evaluate the potassium utilization efficiency.