施钾和补水对旱作马铃薯光合特性及产量的影响

The effect of potassium application and water supplement period on photosynthetic characteristics and tuber yield of potato in semi-arid area

采用裂区试验设计,以施钾水平为主处理,补水时期为副处理,研究了补充供水和钾素处理对马铃薯光合特性及产量的影响.结果表明:施钾能明显增加马铃薯叶片气孔导度、蒸腾速率及光合速率(P<0.05),但施钾提高叶片气孔导度、蒸腾速率、光合速率的程度还依赖于马铃薯受到土壤水分胁迫的程度.在施钾量150 kg/hm2、苗期补水的条件下,产量达到36 324.97 kg/hm2,比不施钾、不补水处理产量提高了32.24%.

In order to reveal the effect of potassium application and water supplement period on the photosynthetic characteristics of potato leaves and its tuber yield in semi-arid area, a field experiment based on split plot design Sciences （the regio was carried out in the Tangjiapu Experiment Station of Gansu Academy of Agricultural nal mean annual precipitation is about 430 mm）, Dingxi City, Gansu Province. The potassium application （at four levels,0 kg/hmz as CK, 75 kg/hm^2, 150 kg/hm2 and 225 kg/hm^2 of potassium fertilizer, respectively） was set up as the main treatment factor, and the water supplement period was chosen as the accessory treatment factor （divided into three patterns of no water supplement as CK, 90 m^3/ hm^2 of water supplement in seedling stage and flowering sta＇ge, respectively）. The results showed that the stomatal conductance, transpiration rate and photosynthetic rate of potato leaves were increased at significant levels（P〈0.05）b tassium application on the condition of potass stage, the tuber yield y applying potassium fertilizer in proper amount. However, the effect degree of pothree physiological indexes also depended on the strength of soil water stress. On ium application rate controlled to 150 kg/hm^2 with water supplement in the seedling of potato reached 36 324.97 kg/hm^2 and increased by 32.24 G compared with CK.