红壤荒地上7种豆科绿肥养分富集能力综合评价

Comprehensive Assessment of Nutrient Enrichment Capacity of 7 Leguminous Green Manures on Red Soil Wasteland

以红壤荒地上春季播种的7种豆科绿肥(竹豆、毛叶苕子、猪屎豆、印度豇豆、乌豇豆、柽麻和田菁)为研究对象,以自然生长的杂草为对照,根据各品种地上部生物量和大量(C、N、P、K)、中量(Ca、Mg、S)及微量(Fe、Mn、Cu、Zn)元素含量计算养分积累量,运用主成分分析对不同品种绿肥养分富集能力进行综合评分,以期筛选出适宜红壤荒地的优良夏绿肥品种。结果表明,印度豇豆、柽麻和乌豇豆的地上部鲜重和干重最高,分别是对照的2.13~4.37倍和1.65~2.32倍,而毛叶苕子地上部生物量最低,鲜重和干重仅为对照的16.5%和27.2%。印度豇豆各种养分元素含量均处于较高水平,其中量和微量元素的积累量在供试绿肥品种中最高。不同品种绿肥养分富集能力综合得分排序为:印度豇豆(1.59)>柽麻(0.90)>乌豇豆(0.60)>杂草对照(-0.14)>竹豆(-0.41)>田菁(-0.63)>猪屎豆(-0.77)>毛叶苕子(-0.94),表明印度豇豆最适宜在红壤荒地上作为夏绿肥推广种植,柽麻和乌豇豆也具有一定的种植潜力。

In this study, seven leguminous green manure crops(Crotalaria junceal, Vicia villosa Roth, Crotalaria pallida, Vigna uniguiculata, Vigna cylindrica Skeels, Sesbania cannabina, and Phaseolus calcaltus), sown in the red soil wasteland in spring, were taken as the research objects, and natural growing weeds were taken as the control. Nutrient accumulations were calculated based on the aboveground biomass, macroelements(C, N, P and K), medium elements(Ca, Mg and S) and trace elements(Fe, Mn, Cu and Zn). Principal component analysis was used to comprehensively score the nutrient accumulation capacity of different green manures with a view to selecting optimum summer green manure crops for wasteland of red soil. The results showed that fresh and dry weight(aboveground) of Vigna uniguiculata, Sesbania cannabina and Vigna cylindrica Skeels were highest, which were 2.13~4.37 and 1.65~2.32 times of those of the control, respectively. Vicia villosa Roth was lowest in aboveground biomass, fresh and dry weight of which were only 16.5% and 27.2% of those of the control, respectively. Vigna uniguiculata had high nutrient elements, and the accumulations of medium and trace elements were highest among all green manure varieties. The comprehensive scores of nutrient accumulation capacity of different varieties of green manure were ranked as follows: Vigna uniguiculata(1.59)>Sesbania cannabina(0.90)>Vigna cylindrica Skeels(0.60)>native weeds of control(-0.14)>Crotalaria junceal(-0.41)>Phaseolus calcaltus(-0.63)>Crotalaria pallida(-0.77)>Vicia villosa Roth(-0.94). Therefore, Vigna uniguiculata is most suitable to be cultivated as summer green manure in wasteland of red soil according to this study, and Sesbania cannabina as well as Vigna cylindrica Skeels are of certain planting potential.