川半夏生长期氮、磷、钾营养吸收特性研究

Nutrient uptake characteristics of nitrogen,phosphorus and potassium of Pinellia ternate from Sichuan during growth stage

目的：在栽培条件下研究川半夏对氮、磷和钾营养吸收特性，为川半夏高产栽培和合理施肥提供依据。方法：定期采集川半夏s-29和s-33样品，分别测定其各自地上和地下部分氮、磷、钾含量，研究其氮、磷、钾分配和累积规律。结果：川半夏不同生育时期各部分对氮、磷、钾的吸收量不同，其中对钾的吸收量最大，对磷的吸收量最少；在半夏大面积“倒苗”的后，各部分氮、磷和钾含量以及累积总量总体上高于非“倒苗”期。生长期间半夏地上和地下部分磷、钾吸收量间相关系数均达显著水平（P〈0．05），且地下部分磷和氮吸收量问相关系数也达到显著水平（P〈0．05）。半夏生长过程中，每生产100kg千品，大约需要吸收氮5．02～5．64kg，P2O32．44～2．56kg，K2O11．62—13．49kg。结论：川半夏在大田栽培中应当施足底肥，并在6月中旬和8月下旬前后及时追施氮、磷和钾肥，并适当提高钾的比例。追肥方式可采用地下浇施和叶面喷施相结合的方式，川半夏地下部分对磷肥和氮肥的吸收有相互促进的效应。

Objective： To study the absorption characteristics of nitrogen （ N）, phosphorus （ P）, and potassium （K） of Pinellia ternate from Sichuan under the cultivated condition. Method： The samples of P. ternate S-29 and S-33 from Sichuan were regularly collected randomly, the contents of nitrogen, phosphorus and potassium of each part （ aerial and underground parts） were determined, and their distribution and accumulation characters of nitrogen, phosphorus, potassium were also studied. Result： The absorption rate of aerial and underground parts of P. ternate were different in nitrogen, phosphorus, and potassium at different growing stages. Among them, the potassium uptake was the highest, while the phosphorus uptake was the lowest. Totally, the uptakes of nitrogen, phosphorus and potassium of P. ternate from Sichuan during ＂ sprout tumble＂ stage were comparatively higher than that not at ＂ sprout tumble＂ stage. A significant correlation was observed between the phosphorus and potassium uptake of the aerial and underground parts, respec- tively（ P 〈 0.05 ）. And there was also significant positive correlation between the nitrogen and phosphorus uptake at underground parts （ P 〈 0.05）. During the growth stage of P. ternate, for producing 100 kg air-dried P. ternate, 5.02-5.64 kg N, 2.44-2.56 kg P205, 11.62-13.49 kg K20 were needed to be absorbed. Conclusion： P. ternate from Sichuan should be given enough base fertilizer in field cultivation, and then be supplied with phosphorus and potassium by combining foliar spray with field application during the middle ten days of June and last ten days of August. The ratios of potassium should be properly improved. There was promoting effect in the phosphorus and nitrogen assimilations of the underground parts of P. ternate from Sichuan.