Controlled seed deterioration in Tagetes patula L. cultivars

This work followed seed behaviour of Tagetes patula cultivars Spry, Orange, Flame and Yellow tinder controlled deterioration conditions and also established viability equation constants. Seed moisture contents (me) were adjusted at 25 degrees C from initial values (+/- 7.0%), either by rehydration above water or by dehydration over silica gel. Seed sub samples were sealed in laminated aluminium-foil packets and stored in incubators maintained at 40, 50 and 65 degrees C (+/- 0.5 degrees C) until the complete survival curves were obtained. The species presented orthodox behaviour during storage. An inverse relationship between seed me and longevity was detected. Different viability constant sets were estimated to predict seed longevity of the cultivars. The viability constant set calculated for the species T. pautula was: K-E = 12.22, C-W = 3.114; C-H = 0.2769, C-Q = 0.002212.