ABSTRACT

There is a wide application of rhizobia inoculants to legume crops in Africa, irrespective of the soil acidity, though the latter limits the effectiveness of inoculants. Two trials were conducted in a controlled environment to determine suitable soil pH and impact of liming on soybean nodulation and nitrogen fixation to inform proper application of the rhizobia-inoculant technology on acid soils. In the first trial; soil, variety and inoculation had significant influence (p < 0.05) on weighed nodule effectiveness (WNE) and N fixation. Strongly acidic soils recorded low WNE and N fixation. In the second trial, WNE and N fixation significantly increased with co-application of lime and inoculation (p < 0.05). The results showed that soybean inoculation is effective in increasing nodulation and N fixation in moderate acidic soils, contrarily to strongly acidic soils. Interestingly, co-application of lime and inoculation has potential of increasing nodulation and N fixation in strongly acidic soils. The WNE is recommended as a robust formula to report nodule effectiveness, compared to the current percentage method.

摘要

不管土壤酸度如何，根瘤菌孕育剂在非洲的豆类作物中都有广泛的应用，尽管后者限制了孕育剂的有效性。在受控环境中进行了两项试验，以确定合适的土壤pH值和石灰对大豆结瘤和固氮的影响，以指导根瘤菌-接种物技术在酸性土壤上的正确应用。在第一次审判中；土壤，品种和接种方式对称重结节有效性（WNE）和固氮都有显着影响（p  <0.05）。强酸性土壤记录的WNE和N固定率低。在第二项试验中，同时施用石灰和接种后，WNE和N的固着力显着增加（p <0.05）。结果表明，在强酸性土壤中，接种大豆可有效增加中度酸性土壤的结瘤和固氮作用。有趣的是，在强酸性土壤中，石灰的同时施用和接种有增加结瘤和固氮的潜力。与当前的百分比方法相比，建议将WNE作为报告结节有效性的可靠公式。