Muerte celular inducida por condiciones ambientales adversas en Calibrachoa parviflora (Petunia)

Abstract

It has been previously reported that extreme environmental conditions such as high temperatures, ultraviolet light and the\ngreenhouse effect, alter the rate of growth in plants. In this study we investigated the acute effect of two extreme\nenvironmental conditions: nutrient deprivation and soil acidification with sulfuric acid, a compound commonly deposited in\nthe soil, as a result of acid rain, on the rate of death and cell proliferation in petunias (Calibrachoa parviflora). For this\npurpose, a group of petunias was subjected to three different conditions: group A or control, kept in optimum conditions\nand nutrient supply, group B in the absence of nutrients and natural light and group C, exposed to water acidified with\nsulfuric acid. In continuous observations for up to 72 hours, samples from petals, leaves and stems of each plant were\nanalyzed and after nuclei extraction; these were treated with propidium iodide, a DNA intercalator compound, and\nanalyzed by flow cytometry and fluorescence microscopy. The results show that both extreme conditions generate an\nimbalance in the process of death/survival of petunias, but unlike plants from group B, plants in group C, did not increase\ntheir rate of cell proliferation. These results suggest that plants growing in acid soils lose their ability to compensate the\nstress signal generated as a result of acute exposure to toxic concentrations of sulfuric acid.