Estimates indicate that 30% of land surface globally is affected by soil acidity, influencing agricultural production. Application of lime increases soil pH and improves crop growth. We tested the hypothesis that liming will reduce rigid ryegrass (Lolium rigidum Gaudin) growth by improving the competitive ability of the crop. Experiments at Merredin and Wongan Hills in Western Australia indicated that application of lime in previous years reduced L. rigidum density, biomass, and seed production in wheat (Triticum aestivum L.) crops in 2018. At Merredin, L. rigidum seed production in 2018 was reduced from 9,390 to 2,820 seeds m−2, and wheat tiller number and yield was increased, following lime application of 0 to 6,000 kg ha−1 in 2016. At Wongan Hills, lime application of 4,000 kg ha−1 in 1994 reduced seed production in the 2018 wheat crop from 4,708 to 1,610 seeds m−2, and application of 3,000 kg ha−1 of lime in 2014 reduced seed production from 3,959 to 921 seeds m−2 in 2018. Again, lime increased wheat tiller number, but not yield. A screen house experiment (in controlled conditions) indicated that lime application increased the initial growth of both L. rigidum and wheat seedlings. This supports the conclusion that reduced L. rigidum growth and seed production in the field resulted from increased competitive ability of the crop, rather than any direct and detrimental impact of lime on L. rigidum growth. Incorporation of lime reduced initial emergence of L. rigidum in controlled conditions, with L. rigidum seeds at a uniform depth, and in the field experiments in situations of high weed density, with seeds buried by the incorporation process. Nationally, the revenue loss from residual L. rigidum in crop is A$93 million per year. The current research confirms that application of lime will increase the competitive ability of crops growing in regions with acidic soils.

中文翻译：

---

改善土壤酸度——减少小麦中硬质黑麦草 (Lolium rectangle) 的生长

估计表明，全球 30% 的土地表面受到土壤酸度的影响，从而影响农业生产。施用石灰可提高土壤 pH 值并促进作物生长。我们检验了石灰会减少硬质黑麦草的假设（黑麦草Gaudin) 通过提高作物的竞争能力来增长。在西澳大利亚 Merredin 和 Wongan Hills 的实验表明，前几年石灰的施用量减少了刚体乳杆菌小麦的密度、生物量和种子产量（小麦L.) 2018 年的作物。在 Merredin，刚体乳杆菌2018 年种子产量从 9,390 粒减少到 2,820 粒米-2，在施用 0 至 6,000 kg ha 石灰后，小麦分蘖数和产量增加-12016 年。在 Wongan Hills，石灰施用量为 4,000 公斤/公顷-11994 年将 2018 年小麦作物的种子产量从 4,708 减少到 1,610 米-2, 施肥 3,000 kg ha-12014 年的石灰量将种子产量从 3,959 减少到 921 米-22018 年。同样，石灰增加了小麦分蘖数，但不增加产量。筛房实验（在受控条件下）表明石灰应用增加了两者的初始生长刚体乳杆菌和小麦苗。这支持了减少的结论刚体乳杆菌田间的生长和种子生产是由于作物竞争能力的提高，而不是石灰对作物的任何直接和有害影响刚体乳杆菌生长。石灰的加入减少了初始出苗刚体乳杆菌在受控条件下，与刚体乳杆菌种子深度均匀，在杂草密度高的情况下进行田间试验，种子通过掺入过程掩埋。在全国范围内，剩余收入损失刚体乳杆菌每年的作物产量为 9300 万澳元。目前的研究证实，石灰的应用将提高在酸性土壤地区生长的作物的竞争能力。