Descriptors :
Department of horticulture,College of agriculture,Isfahan University of Technology,Isfahan,Iran
Abstract :
Experiments were carried out to determine the effects of various constant (6,10,15,20,25,30 and 35 C)and alternating temperatures (15/5,20/10and 30/20 C)on germination in two cvs of taree (Allium ampeloprasum L. spp. iranicum W.)namely,Shadegani and Isfahani. Linear relationships were demonstrated between reciprocal of time taken to 50,germination (G**50) and temperatures. There was a good linear relationship (p<0.001,r**2 =0.99)between temperture and rate of germination for each case. Three cardinal temperatures for germination established by extrapolation of regression lines relating of 50,germination to temperature.These three cardinal temperatures:base (T***b), optimum (T***0)and maximum (T***m)were 0.82, 19.4 and 40.43 C respectively in cv Shadegani. In cv Isfahani, cardinal temperatures were then calculated and they were 0.5, 19.52 and 40.52 C. The thermal times required for 50,germination were 62.5 and 61.5 C in cvs Shadegani and Isfahani, respectively. Thermal time for final germination were 200.1 Cd in cvs Shadegani and Isfahani, respectively. Thermal time for final germination were 200.1 Cd in cv Shadegani and 188.1 Cd in cv Isfahani. No siginificant differences were found in thermal time required for germination between two cultivars (P>0.05). Differences in the rate and thermal times for (G**50)were not statistically significant under both constant or alternating temperatures (P>0.05).
