云南红壤上蓖麻干物质积累和N、P、K吸收规律研究

Study on dry matter accumulation and N、P、K absorption of castor in red soil of Yunnan

选用蓖麻品种TCO-202为试验材料,测定苗期、现蕾期、开花期、灌浆期、成熟期根、茎、叶、花序各器官的干物质积累和氮(N)、磷(P)、钾(K)吸肥量。结果表明,干物质积累速率从出苗到灌浆呈上升趋势,到灌浆期达最大值,灌浆期以后上升速度开始减慢。各个时期干物质积累量大小依次为:开花至灌浆期>苗期至现蕾期>灌浆期至成熟期>现蕾期至开花期>苗期;蓖麻氮、磷、钾的吸收量在整个生育期遵从“慢—快—慢—快—慢”的规律,吸收速率呈现双驼峰型,2个吸肥速率高峰出现在现蕾期和灌浆期;在云南红壤上蓖麻每生产100kg籽粒需氮(N)7.71kg,磷(P)1.26kg,钾(K)4.42kg,吸肥比例为1∶0.16∶0.57。

Dry matter accumulation in root, stem, foliage, inflorescence and the absorption of N, P, K in seedling, budding, blooming, filling and maturity stages were measured separately using castor （Ricinus communis L. ） variety TCO -202. Results indicated that the accumulation of dry matter kept ascending after emerging until filling stage, then slowed down. The order of accumulation rate in each stage was ： blooming to filling stage 〉 seedling to budding stage 〉 filling to maturity stage 〉 budding to blooming stage 〉 seedling stage. The absorption amount of nitrogen （N） , phosphorus （P） and potassium （K） of castor in the whole growth duration complied with the law of ＂slow - fast - slow - fast - slow＂, and the function curve of absorption speed showed a type of hump with two pinnacles in budding and filling stage. Results also showed that producing every 100g castor grain in red soil in Yunan needed 7.7 lkg nitrogen （ N ） , 1.26kg phosphorus （P） and 4.42kg potassium （K） , respectively, with a fertilizer absorption proportion of 1： 0.16： 0.57.