Abstract An acid Alfisol (Typic Paleustalfs) was amended in triplicates at the rate of 5 g kg−1 soil (12 t/ha) with organic amendment (cow dung (CD), corn cob (CC) and 1:1 CD:CC (CDCC), and 20 kg N ha−1 as urea, respectively, and planted to cowpea in the screenhouse. At flowering stage, plant shoots, roots and nodules were harvested. N2 fixed was estimated by N-difference method using maize planted and treated the same way as the cowpea as non-fixer. Considering average data for two planting periods, the increases (p < 0.05) obtained with the application of both organic manure with and without N over the control ranged from 125–775% for number of nodules, 96–296% for N2 fixed, 36–99% for dry matter yield and 160–460% for seed yield. The parameters were higher (p < 0.05) in the organic –inorganic N than in sole manure treatments. The organic amendments increased the pH, organic carbon (OC) and available P contents of the soil at both plantings, with CDCCN and CDCC recording the highest values. Average tissue N and P at the end of the two plantings were similar among all treatments, but average N and P uptakes were higher (p < 0.05) with than without amendments by 26–100% and 238–340%, respectively. Therefore, 5 g kg−1 cow dung:corn cob (1:1) or 5 g kg−1 cow dung in sole application or combined with 20 kg N ha−1 can promote cowpea growth, N2 fixation and yields with resultant positive effects on soil chemical properties.

中文翻译：

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豇豆 (Vigna unguiculata L. Walp) 的生长、固氮和产量以及酸性 Alfisol 的化学性质对有机添加物和无机 N 的应用的响应

有机添加物增加了两种种植土壤的 pH 值、有机碳 (OC) 和有效磷含量，CDCCN 和CDCC 记录了最高值。两种种植结束时的平均组织 N 和 P 在所有处理中相似，但平均 N 和 P 吸收量比没有修正时高（p < 0.05），分别高出 26-100% 和 238-340%。因此，5 g kg−1 牛粪：玉米芯 (1:1) 或 5 g kg−1 牛粪单独施用或与 20 kg N ha−1 结合可促进豇豆生长、固氮和产量，从而产生积极影响关于土壤化学性质。但平均 N 和 P 吸收量比没有修正的情况下分别高 (p < 0.05) 26-100% 和 238-340%。因此，5 g kg−1 牛粪：玉米芯 (1:1) 或 5 g kg−1 牛粪单独施用或与 20 kg N ha−1 结合可促进豇豆生长、固氮和产量，从而产生积极影响关于土壤化学性质。但平均 N 和 P 吸收量比没有修正的情况下分别高 (p < 0.05) 26-100% 和 238-340%。因此，5 g kg−1 牛粪：玉米芯 (1:1) 或 5 g kg−1 牛粪单独施用或与 20 kg N ha−1 结合可促进豇豆生长、固氮和产量，从而产生积极影响关于土壤化学性质。