氮素水平对雾培马铃薯氮磷钾吸收、积累和分配规律的影响

Effects of Nitrogen Levels on N, P and K Uptake, Accumulation and Distribution of Potato by Aeroponics

【目的】为优化雾培马铃薯原原种生产技术,为雾培原原种生产氮素营养管理提供科学的理论依据,本文研究了氮素水平对不同生育期养分吸收、积累与分配规律的影响。【方法】试验采用双因素随机区组设计,以品种川芋117和米拉为试验材料,设5个氮素水平(120、240、360、480、600 mg/L),在雾培不同生育期分别测定各器官干重和氮、磷、钾含量,分析其干物质积累、氮磷钾养分吸收积累及分配。【结果】(1)同一氮素水平下,相同生育期米拉的单株干物质积累量均大于川芋117,不同品种和生育期,均在氮素水平为240 mg/L单株干物质积累量达到最高,在定植90 d时,川芋117和米拉分别达到2.86和4.23 g/plant;(2)氮素水平增加有利于2个品种各生育期植株各器官氮磷钾含量的提高,定植90 d,2个品种均在240 mg/L氮素处理植株的氮、磷、钾养分积累量最高,川芋117分别为0.306、0.070、0.544 g/plant,米拉分别为0.489、0.117、0.899 g/plant;(3)不同品种和生育期,中氮处理的叶、茎和根的氮、磷、钾分配比例大于低、高氮处理,而块茎则与之相反,生育前期,氮、磷和钾在叶、茎和根中比例大于块茎,生育后期,营养元素往块茎转移;(4)2个品种均在氮素水平240 mg/L单株结薯数、结薯产量达到最高,川芋117和米拉分别为24.78粒/株,53.78 g/株和29.31粒/株和82.23 g/株。【结论】适量增氮,可以促进植株对氮、磷和钾的吸收积累,有利于原原种产量的提高。在四川盆地弱光生态条件下雾培马铃薯,240 mg/L的氮素水平可以获得较高的原原种产量。

【Objective】The present paper aimed to optimize pre-basic seed production and manipulate N nutrient management by aeroponics, effects of N levels on N, P and K uptake and distribution of potato during different growth stages were studied.【Method】The experiment was laid out in a randomized block design of two factors with two potato cultivars of Chuanyu117 and Mira by aeroponics. N levels were set at 5 levels of 120, 240, 360, 480 and 600 mg/L. In different growth stages, dry matter weight, nitrogen, phosphorus and potassium contents of different parts of plant were measured. Dry matter accumulation, nitrogen, phosphorus and potassium contents, uptake and distribution were analyzed.【Result】(i)In the same N level, the dry matter accumulation of Mira was higher than that of Chuanyu 117 at the same grow period. The highest dry matter accumulations were achieved under the N level 240 mg/L in the same growth stages with two cultivars. The dry matter accumulation of Chuanyu 117 and Mira was 2.86 and 4.23 g/plant in N Level 240 mg/L at 90 days after transplanting(DAT) respectively.(ii)The content of Nitrogen(N), phosphorus(P) and potassium(K) in different organs increased as the nitrogen level increased at different growth stages with the two cultivars. The uptake and accumulation of N, P and K was higher under the N 240 mg/L treatment than that of other N levels at 90 DAT, respectively, Chuanyu117 were 0.306, 0.070 and 0.544 g/plant respectively;Mira were 0.489, 0.117 and 0.899 g/plant.(iii)At the same growth periods, the distribution ratio of N, P and K in leave, stem and root under middle N levels was higher than that of low or high N levels, but the effect on tubers was contrary to the above. The distribution ratio of N, P and K in leave, stem and root was high at the early stage, and then N, P and K was transferred to tubers in the late growth stages.(iv)The tuber number and weight per plant reached a maximum under the N level of 240 mg/L with the two cultivars, respectively,was 24.78 grain/plant, 53.78 g/plant for Chuanyu 117, and 29.31 grain/plant, 82.23 g/plant for Mira.【Conclusion】Increasing nitrogen in an appropriate amount can promote the uptake and accumulation of nitrogen, phosphorus and potassium in plants, which is beneficial to the improvement of pre-basic seed production. Under the condition of low light intensity ecology in Sichuan basin, we can obtain higher yield of potato pre-basic seeds under nitrogen level of 240 mg/L by aeroponics.