Resumen

CALZADA LOPEZ, Sandra Guadalupe et al. Cardinal temperatures and germination rate in husk tomato cultivars. Rev. Mex. Cienc. Agríc [online]. 2014, vol.5, n.spe8, pp.1451-1458. ISSN 2007-0934.

Knowledge of the cardinal temperatures and germination rate may be useful as a criterion for determining planting dates and locations of a given species. These variables (temperature and rate) have been determined for a number of crops. However, this information is not available for husk tomato cultivars (Physalis philadelphica Lam.), even though this species ranks fourth in importance among the vegetables grown in Mexico. The aim of this study was to determine the cardinal temperatures and germination rates of seeds of Diamante, Chapingo, Tecozautla and Cerro Gordo husk tomato cultivars. The presence of latency in these cultivars was discarded. This study was conducted in the Postgraduate College and the Autonomous University of Chapingo in 2011-2012. In germination chambers, seeds were germinated on filter paper in Petri dishes in darkness and constant temperature of 3, 5, 7, 9, 10, 15, 20, 25, 30, 35, 40 and 45 °C, a completely randomized factorial experimental design with five replications per cultivar was used. The germinated seeds (emerged radicle) were counted and discarded every five days for 25 days. The cardinal temperatures for germination of Diamante, Chapingo, Tecozautla and Cerro Gordo cultivars were: minimum: 7-9, 9, 7, 10 °C; optimum: 25-30, 30, 30, 25-30 °C respectively; maximum: 45 °C for all cultivars. The highest germination rates were: 23.4, 23.6, 21.8 and 18.7 seeds per day, respectively.

Palabras llave : Physalis philadelphica Lam; minimum; optimum and maximum temperature; latency.