DIGITALNA ARHIVA ŠUMARSKOG LISTA

prilagođeno pretraživanje po punom tekstu

ŠUMARSKI LIST 5-6/2017 str. 41 <-- 41 --> PDF |

weeks pre-chilling at 4 °C, as well as the 4 weeks warm incubation at 12 °C subsequently 9 weeks cold stratification at 4 °C (4wW+9w). Germination tests were done in 11 cm diameter Petri dishes on two layer of filter paper moistened with distilled water with 150 seeds (3×50) at 12 °C. The seeds were checked every 4 days and the germinated seeds were recorded and removed. Germination tests were continued for 92 days. The seeds were removed from Petri dishes after their radicles were elongated for 3 mm. To investigate the effects of GA _{3} on the dormancy and the germination, seeds from two different provenances (Adana and Mersin) were tested. Two types of seed were used, non–pre-chilled and 8 weeks pre-chilled. Both types of seed were subjected to different GA_{3} hormone doses (100 ppm and 500 ppm) for 24 hours.Germination percentage (GP) and mean germination time (MGT) were calculated according to following formulas (Bewley et al., 2013):GP(%)=(∑n _{i}/N)×100where GP is the germination percentage, n _{i} is the number of germinated seeds at week i, and N is the total number of incubated seeds per tests; andMGT=∑(t _{i}.n_{i})/∑n_{i}where MGT is the mean germination time, t _{i}_{ }is the number of weeks from the beginning of the test, and n_{i} is the number of germinated seeds recorded on week t_{i}.Morphological characteristics of cones and seeds, germination percentage as well as mean germination time were analyzed using ANOVA. The percent values (GP) were transformed using arc sin square root before variance analyses. RESULTS REZULTATI The average cone length, cone diameter and cone weight were 22.49 mm, 20.86 mm and 4.659 g respectively. There were no significant differences between provenances in terms of cone length and cone diameter. Adana provenance had the heaviest cone in average. Average woody part length, diameter and weight were 17.62 mm, 14.76 mm and 2.34 g in order. The average pulp weight was 2.22 g. The average number of seeds were 2.2 and the average seeds weight 0.097 g. Average woody part, pulp part and seed weight percentage in a cone were 50.69%, 47.18% and 2.12% respectively. Average 1000-seed weight for three provenances was 44.66 g at about 5.4%MC. The average seed length, width, thickness and weight were 10.07 mm, 3.30 mm, 2.77 mm and 0.045 g respectively. There were no significant differences between the provenances in terms of seed width and thickness. Kahramanmaraş provenance had the heaviest seed in average (Table 2). Pre-chilling applications of 4 w and 8 w were inadequate for breaking the dormancy. By contrast, 12 w and 16 w pre-chilling applications increased the germination percentages, but these treatments didn’t eliminate the dormancy completely. 4 week warm stratification subsequently with 9 w pre-chilling resulted in the highest germination percentage. After the 0-w, 4-w, 8-w, 12-w, 16-w, and 4w warm stratification +9 w pre-chilling average germination percentages were 6%, 15.3%, 14.2%, 26.9%,27.8%, 65.3% respectively (Table3). Mean germination time of seeds after different applications at germination temperature at 12 °C is presented in Table 4. Gibberellic acid was applied to 8-w pre-chilled and non-pre-chilled seeds which were collected from Adana and Mersin provenance. The hormone didn’t increase germination percentage innon pre-chilled seeds. On the contrary, this - |