Soil compaction becomes a frequent problem due to the increased traffic of large agricultural machines and implements necessary for crop management. Soil compaction, characterized by increased soil bulk density, prevents root growth, and consequently, the absorption of water and nutrients. Castor may be an alternative crop for cultivation in soils with a compaction problem because it has a vigorous root system that could break the compacted soil layers, consequently improving the soil quality for the next growing season. This study aimed to evaluate the growth of dwarf castor hybrids under different soil bulk density levels. A randomized block design with four replications in a 4 × 5 factorial scheme was used. Four castor genotypes were evaluated (two hybrids and two cultivars) under five soil bulk densities: 1.09; 1.30; 1.51; 1.72 and 1.93 Mg m⁻³. The plants were grown in pots assembled from three overlapping 200 mm diameter polyvinyl chloride (PVC) rings until 56 days after emergence. There was no interaction among the soil bulk density and castor genotypes for all variables. The genotypes had the same behavior under high soil bulk density conditions, and similar values were observed of shoot and root dry matter partitioning in the three soil layers between dwarf castor hybrids and castor cultivars. The genotypes accumulated from 68–71% of dry mass in the shoot, and the remaining (29–32 %) was accumulated in the roots. The highest root and shoot dry matter accumulations were estimated with soil bulk density around 1.60 Mg m⁻³. The results suggest that castor can be grown in areas with soil compaction problems.

由于大型农业机械和农作物管理所必需的工具的增加，土壤压实成为常见的问题。以土壤堆积密度增加为特征的土壤压实可以防止根系生长，从而防止水分和养分吸收。蓖麻可能是具有压实性问题的土壤中耕种的替代作物，因为它具有旺盛的根系，可以破坏压实的土壤层，从而改善下一个生长季节的土壤质量。这项研究旨在评估矮脚轮杂种在不同土壤容重水平下的生长。使用以4×5析因方案进行四次重复的随机区组设计。在五个土壤容重下，评估了四种蓖麻基因型（两个杂种和两个品种）：1.09； 10。1.30; 1.51；1.72和1.93 Mg m⁻³。将植物放在由三个重叠的直径200毫米的聚氯乙烯（PVC）环组装而成的盆中生长，直到出苗后56天。对于所有变量，土壤容重和蓖麻基因型之间没有相互作用。这些基因型在高土壤容重条件下具有相同的行为，并且在矮脚蓖麻杂种和蓖麻品种之间的三个土壤层中观察到的芽和根干物质分配具有相似的值。基因型在芽中占干重的68-71％，其余（29-32％）则在根部。估计最高的根和茎干物质积累，土壤容重约为1.60 Mg m ^-3。结果表明，蓖麻可以在土壤紧实的地区生长。