Masoud Borhani; Hosein Arzani; Mehdi Basiri; Mohammad Ali Zare Chahouki; Mehdi Farahpour
Volume 21, Issue 3 , December 2014, , Pages 530-540
Abstract
In order to investigate the effects of range management plans on cover, production, litter, and regeneration of plants in Semirum rangelands, 54 sites including 29 with plan and 25 without plan were selected. The implementation of range management plans resulted in the decrease of stocking rate, affecting ...
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In order to investigate the effects of range management plans on cover, production, litter, and regeneration of plants in Semirum rangelands, 54 sites including 29 with plan and 25 without plan were selected. The implementation of range management plans resulted in the decrease of stocking rate, affecting the improvement of vegetation. According to the obtained results, no significant differences were found for the mean total cover, production and number of seedlings between two managements (P<0.05), while in the sites with plan, the cover, production and number of seedlings of class 1 plants, and cover and production of perennial grasses were significantly more than those of the sites without plan. This result was also true in the case of litter. These variations in plant composition were due to the impact of controlling the intensity and timing of grazing on the competition between palatable and perennial species with invasive and annual ones.
Amir hosein Shaarbaf esfahani; Mahdi Basiri; Mohammad reza Karim zadeh; Mojtabah Modares hashemi
Volume 16, Issue 2 , December 2009, , Pages 137-149
Abstract
Fall planting of forage legumes normally is not successful in central Zagross mountain region because of possibility of germination after autumn rainfall and mortality of seedling by early frost during fall season. For planting legumes in the spring there are limitations since seed planted after early ...
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Fall planting of forage legumes normally is not successful in central Zagross mountain region because of possibility of germination after autumn rainfall and mortality of seedling by early frost during fall season. For planting legumes in the spring there are limitations since seed planted after early spring rainfalls cannot be successfully established. During early spring rainfall period high soil moisture does not allow planting operations. Therefore government projects for rehabilitation of abandoned dry farming lands can not use seeds of forage legumes such as Medicago sativa(Me.sa), Onobrychis viciaefolia(On.vi) and Vicia villosa(Vi.vi) with good quality forage and proper yield with high adaptability to soil and environmental conditions of the region. To solve the problem، this research was conducted to evaluate the effect of seed treatments with germination inhibitors and hydrophobic materials as well as seed pelleting in Shahid Fozveh research station in germinators and green house. Caffeine, vanillin and extract of Eucalyptus leaves were used as inhibitors. Poly ethylene glycol 6000(PEG) and Di- manitol(DM) were used as hydrophobic substances. Seed pelleting was achieved by using a coating drum device. Treated seeds were put in germinator with 25ºС constant temperature. Velocity coefficient of germination, percent germination, germination commencement delay and alometric ratio were determined. Data were analyzed as complete random design and Duncan’s test was used to determine significant differences. Results indicated that vanillin caused 18 and 14 days germination delay for Me.sa and Vi.vi respectively. Vanillin and extract of Eucalyptus leaves delayed germination of On.vi unshelled seeds for 21 and 22 days respectively and proved to be best materials for this purpose. Caffeine reduced germination percentage of all seeds. PEG and DM delayed germination only for 3 to 7 days, not long enough to be useful for practical purposes. Pelleted seeds without inhibitors and hydrophobes showed 9 to13 days germination delay. Pelleting along vanillin treatment caused 20 and 16 days delay in germination of Me.sa and Vi.vi respectively. Pelleted unshelled seeds of On.vi treated with vanillin and extract of Eucalyptus leaves had germination delays for 26 and 22 days respectively. With rapid decrease of temperature during fall season in central Zagross region it seems reasonable to consider a delay of more than 15 days to be practically effective to reduce or eliminate mid fall germination of these species and increase success of fall seeding considerably. Further investigations with field planting is recommended.