Abstract Soil compactions are widely dispersed in the world but tend to be the most prevalent, where heavy machinery is used in agriculture. The increasing use of heavy machinery is the primary cause of soil and subsoil compaction. The impact of subsoil compaction on root growth and yield of wheat (Triticum aestivum L) were evaluated during 2006 and 2007. Sub-soil compactions were created by three normal loads, i.e. 4.40, 6.40 and 8.40 kg and four number of passes of tractor, i.e. 1, 6, 11 and 16. The field was divided into 39 plots including a control plot, i.e. no passes of the tractor. The size of each plot was 400 square meter. A factorial randomized block design was followed in laying out the experiment and care was taken that all the 13 treatments and their replications are included in field experiments. It was observed that for all the compaction treatments in the field experiment on the wheat crop, 51–61% of wheat roots were confined in 0–15 cm, 17–20% in 15–30 cm and the rest 22–28% is below 30 cm soil layer. Sub-soil compaction reduced the wheat crop yields to a maximum of 23%. A statistical model is developed to predict crop yield considering the root length density of the crop. Average root diameters increased with the increase of the sub-soil compaction level. In sub-soil zone, average root diameter decreased with the increase of sub-soil compaction level.

中文翻译：

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底土压实对小麦生根行为和产量的影响

摘要 土壤压实在世界范围内广泛分布，但往往是最普遍的，其中重型机械用于农业。越来越多地使用重型机械是土壤和底土压实的主要原因。在 2006 年和 2007 年期间评估了底土压实对小麦 (Triticum aestivum L) 根系生长和产量的影响。 底土压实是由三个正常负载产生的，即 4.40、6.40 和 8.40 公斤以及四次拖拉机通过，即 1、6、11 和 16。田地分为 39 个地块，包括一个控制地块，即没有拖拉机通过。每个地块的面积为400平方米。在布置实验时遵循因子随机区组设计，并注意将所有 13 个处理及其重复都包括在田间实验中。据观察，在小麦作物田间试验中的所有压实处理中，51-61% 的小麦根系被限制在 0-15 cm，17-20% 被限制在 15-30 cm，其余 22-28% 被限制在30厘米土层以下。底土压实使小麦作物的产量最多减少了 23%。考虑到作物的根长密度，开发了一种统计模型来预测作物产量。平均根直径随着底土压实程度的增加而增加。在底土区，平均根径随着底土压实程度的增加而减小。考虑到作物的根长密度，开发了一种统计模型来预测作物产量。平均根直径随着底土压实程度的增加而增加。在底土区，平均根径随着底土压实程度的增加而减小。考虑到作物的根长密度，开发了一种统计模型来预测作物产量。平均根直径随着底土压实程度的增加而增加。在底土区，平均根径随着底土压实程度的增加而减小。