Desempenho fisiológico de sementes e plântulas de pimenta e de tomateiro sob diferentes temperaturas

Abstract

The objective of this study was to evaluate the physiological performance of seeds and pepper and tomato seedlings under the influence of different temperatures. They were conducted separately in two experiments in the Didactic Laboratory of Seed Analysis - FAEM - UFPel. In the first experiment pepper seeds were used Cayenne Long Slim®, and in the second experiment Gaúcho® tomato seeds were employed. In both experiments, the treatments consisted of constant temperatures, as follows: 18; 20; 22; 24 and 26ºC. To determine the physiological performance of the seeds and seedlings were employed germination assessments, first count, germination speed index, accelerated aging, cold test, shoot length and primary root mass of dry matter air and root, seedling emergence at 14 and 21 days after sowing and emergence speed index. The results show that the pepper seed germination is not affected markedly by the temperature from 18 to 24ºC, as well as tomato seeds at a temperature of 18 to 26ºC, which showed no significant difference in germination. The first count, germination speed index and the accelerated aging values were increased linearly with increasing temperature in pepper and tomato. However, the cold test and emergency, both at 14 and at 21 days after sowing, were influenced positively to the approximate temperature of 22°C, for both crops. Thus, the expression of seed vigor of both species is adversely affected by reducing the growth temperature, with remarkable results obtained at temperatures of 18 to 20ºC.