Solanum americanum Mill. is a weed that occurs with a number of crops, and it is known for its high seed production and its staggered germination. The objective of this work was to evaluate the germination behavior of S. americanum seeds under the influence of chemical and environmental factors. In the laboratory, we tested the effect on germination of (i) constant and alternating temperatures, (ii) seed washing, (iii) exposure time and concentration of chemical treatments and (iv) seeding depth and soil covered with plant residue on seedling emergence. The variables analyzed were germination percentage, germination rate index, seedling emergence and length of the seedlings. The results indicated that alternating temperatures are the main way to promote germination of S. americanum; however, chemical treatments can help to increase the germination percentage and rate index. There was no increase in germination with seed washing, with the exception of KNO₃ application. A GA₃ concentration of 0.84 g L⁻¹ and an exposure time of 21.22 h in 0.2% of KNO₃ promoted the highest germination of S. americanum. Germination occurs when seeds remain on the soil surface and are not covered by crop residue.

中文翻译：

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美洲茄种子萌发的化学和环境因素

茄属美国磨坊。是一种与多种作物一起出现的杂草，以其高种子产量和交错发芽而闻名。这项工作的目的是评估在化学和环境因素影响下美洲虎种子的发芽行为。在实验室中，我们测试了 (i) 恒定和交替温度、(ii) 种子清洗、(iii) 化学处理的暴露时间和浓度以及 (iv) 播种深度和被植物残留物覆盖的土壤对幼苗出苗的影响. 分析的变量是发芽率、发芽率指数、出苗率和幼苗长度。结果表明，交替温度是促进美洲虎耳草萌发的主要途径；然而，化学处理有助于提高发芽率和发芽率指数。除了施用 KNO 3 外，种子洗涤没有增加发芽率。GA₃ 浓度为 0.84 g L⁻¹，在 0.2% 的 KNO₃ 中暴露时间为 21.22 小时，促进了美洲虎耳菜的最高发芽。当种子留在土壤表面并且没有被作物残留物覆盖时就会发芽。