مطالعه دماهای کاردینال جوانه‌زنی عروسک پشت پرده (Physalis divaricata) جمعیت استان کردستان

In order to determine of cardinal temperatures and variation of ground cherry′s germination, an experiment and controlled condition on completely randomized design with 4 replications were conducted in to the weed laboratory at Kurdistan University in 2019. Treatments consist of different temperatures 5, 10, 15, 20, 25, 30, 35, 40 and 42.5 ºc. So, for investigating of germination, cumulative germination and germination speed were measured in the tests. The results showed that 5 and 10 ºc have no effect on ground cherry′s germination but others got seeds varied significantly (p= 0.05) in both parameters. The best temperatures about cumulative germination parameter were 40 and 42.5 ºc and the lowest one was the 20 ºc. Whereas the maximum cumulative germination (a), slope of germination variation (b), and germination time of 50 percent (t0) parameters were decreased at least in all time of seed burial treatments strongly but the differences had no significant among time treatments. Also the maximum of germination achieved by the 15 ºc and the 40 ºc was the proper degree through the limited time because got the seeds gained to Germination 50 percent parameter. As well as the 40 ºc has the minimum of variation on condition invariable germination about cumulative germination parameter. Moreover, the minimum of variation in cumulative germination parameter showed in 30 and 42.5 ºc whereas the 40 ºc got seeds achieved to maximum rate germination, decreased faster than other degrees too. Finally, it could be said that for decreasing damage of this weed in summer crops, planting would be done which temperature was about 20 ºc also whether the seed bank was dynamic ones, burial seed seems so proper way at least 2 weeks.