ABSTRACT

Compaction can affect the emergence and growth of seedlings and, consequently, harm the development of the culture. However, there are no standardized methodologies that allow evaluating the characteristics of seedlings grown in high mechanical impedance. Thus, the objective of this research was to develop an efficient, standardized, and reproducible methodology to assess seedling emergence and growth in response to increased mechanical impedance, using soybean as a model crop. The proposal consists of a PVC (polyvinyl chloride) column on a tray, both filled with sand of standardized granulometry. A perforated metallic disk is placed on the surface of the column, which receives loads to simulate different levels of mechanical impedance (0.15; 0.60 and 0.87 MPa). Seeds of four soybean cultivars were planted inside the holes of the discs and cultivated for 7 days. The high penetration resistance of the roots did not affect the final percentage of emergence of soybean seedlings. However, speed and uniformity of emergence; volume, length, diameter, surface area of roots; and biomass production of roots and shoots respond to treatments and provide the screening of soybean cultivars in different groups of mechanical impedance response. The methodology allows an efficient, standardized and reproducible estimation of the percentage and speed of emergence, as well as the growth characters of seedlings under increasing mechanical impedance.

摘要

压实会影响幼苗的出苗和生长，从而损害培养物的发展。然而，没有标准化的方法可以评估在高机械阻抗下生长的幼苗的特性。因此，本研究的目的是开发一种有效、标准化和可重复的方法来评估幼苗的出苗和生长，以响应增加的机械阻抗，使用大豆作为模式作物。该提案包括一个托盘上的 PVC（聚氯乙烯）柱，两个柱子都充满了标准化粒度的沙子。一个穿孔的金属盘放置在柱子的表面，它接收负载以模拟不同水平的机械阻抗（0.15；0.60 和 0.87 MPa）。将四个大豆品种的种子种植在圆盘的孔内并培养 7 天。根部的高抗穿透性不影响大豆幼苗的最终出苗率。然而，出苗的速度和均匀性；根的体积、长度、直径、表面积；根和芽的生物量产生对处理的响应，并提供对不同组机械阻抗响应的大豆品种的筛选。该方法可以有效、标准化和可重复地估计出苗的百分比和速度，以及在机械阻抗增加的情况下幼苗的生长特征。根的体积、长度、直径、表面积；根和芽的生物量产生对处理的响应，并提供对不同组机械阻抗响应的大豆品种的筛选。该方法可以有效、标准化和可重复地估计出苗的百分比和速度，以及在机械阻抗增加的情况下幼苗的生长特征。根的体积、长度、直径、表面积；根和芽的生物量产生对处理的响应，并提供对不同组机械阻抗响应的大豆品种的筛选。该方法可以有效、标准化和可重复地估计出苗的百分比和速度，以及在机械阻抗增加的情况下幼苗的生长特征。