جستجوی مقالات مرتبط با کلیدواژه « germination percent » در نشریات گروه « منابع طبیعی »

The genus Grammosciadium of the Apiaceae family has nine species, of which three species pterocarpum, G. platycarpum and G. scarbridu grow in Iran, which grow in most temperate or cold temperate regions and in mountain pastures. G. platycarpum species is a perennial plant with a height of 40 to 100 cm, which is known as mountain parsley or mountain dill and is distributed in Iran, Turkey, Iraq and Armenia. It is used as an infusion to reduce fat and blood sugar and as Vegetables are consumed raw and cooked in some regions of Iran. It has a pleasant taste and smell and is used as a vegetable and food additive in different regions in spring. Since wild and medicinal plants usually have weak and uneven germination, therefore, the use of methods to improve germination can have a positive effect on improving the production of these plants. Therefore, the purpose of this research is to investigate the effect of stratification and gibberellic acid pretreatments on seed germination characteristics and to determine the best method of seed treatment to improve the germination of mountain G. platycarpum seeds.

To investigate the impact of stratification and gibberellic acid pretreatments on the germination and growth indices of platycarpum, an experiment was conducted in the Ecophysiology Laboratory of Medicinal Plants, Medicinal Plants and Drugs Research Institute of Shahid Beheshti University of Tehran during 2023. The seeds used in this experiment were collected in August 1402 from its habitats in the northwest of the country from the city of Mahabad (longitude: 45°40', latitude: 36°41', altitude: 1426) located in West Azarbaijan province. In order to improve the germination indices of mountain dill seeds, an experiment in a factorial format based on a completely randomized design with two factors of wet chilling at 4 times (0, 2, 4 and 8 weeks) and gibberellic acid at four concentrations (0, 300, 500 and 700 ppm) was implemented with three iterations in 2023. Before conducting the experiment, in order to disinfect the seeds collected from nature, they were disinfected with a 1% sodium hypochlorite solution and then with a 70% ethanol solution for 5 minutes in each step, and then they were disinfected with distilled water in several steps and then They were washed with distilled water in several stages. In order to apply gibberellic acid treatment, concentrations of 300, 500 and 700 ppm were prepared and the seeds were soaked in it for 48 hours. In each petri dish, 40 seeds were placed on a filter paper and placed in the refrigerator at 4°C for wet chilling treatment, and according to the treatments, after 0, 2, 4 and 8 weeks and adding 10 ml of water to the germinator at 25°C, 60% relative humidity and 12 hours of light and 12 hours of darkness were transferred. Germinated seeds were counted daily 24 hours after the start of the experiment. The seeds whose roots were visible (that is, about 2 mm long) were counted as germinated seeds and the results were recorded. Germination percentage, germination rate, mean germination time, seedling vigor, fresh and dry weight of seedlings were measured.

The results showed that with increasing the duration of stratification and increasing the concentration of gibberellic acid, the germination percentage, germination rate germination, rate index, seedling vigor, fresh and dry weight of the seedling improved and had a significant difference compared to the control. The highest germination percentage (94.66 percent), germination rate (90.66 seeds per day), germination index (5.2), seedling vigor (2325), fresh weight (1.51 g) and dry weight (0.41g) seedlings were observed in the combined treatment of 700 ppm gibberellic acid and stratification for 8 weeks. Also, the lowest mean germination time (1.6 days) was obtained in the treatment of 700 ppm gibberellic acid and 8 weeks of stratification, and the longest (6.93 days) was in the control.

Familiarity with the seeds of medicinal plants and knowledge of their germination characteristics can be a big step in domestication, development of their cultivation methods and prevention of their extinction in natural habitats. In general, the results of this research showed that the combined use of 700 ppm gibberellic acid with 8 weeks of stratification was the best treatment in breaking dormancy and seed germination of platycarpum. Based on the results of G. platycarpum dormancy breaking treatments and the use of gibberellic acid was able to replace part of the cold requirement, it can be concluded that G. platycarpum has different degrees of physiological dormancy.

This research was done during 2015-2016 as split-plot experiment as RCD with 3 replication in laboratory of Agriculture and Natural Resources Research Center, Zanjan. Sowing date of mother plant as main-plot in 3 levels contained: D1: 7 Oct 2011, 2012 D2: 22 Oct 2011, 2012 D3: 6 Nov 2011, 2012 and 10 cultivars of mother plant included: Opera, Karaj3, KR4, GAo96 × Zarfam (1)(2), Okapi × GAo96 (2)(5), Orient × Modena (2)(4), Orient × Modena (5)(4), Okapi × GAo96 (2)(2), Okapi × GAo96 (5)(2) and GAo96 × Zarfam (5)(1) as sub-plots were considered that conducted in a two year experiments as split-plot as base of RCBD. The studied traits included: germination percent, time required for germination, germination rate, root length, shoot length, seedling dry weight. The result of variance analysis showed that sowing date and cultivar simple effect were significant on mentioned traits. Sowing date and cultivar interaction also was significant effect on mention characteristics. The mean comparison of sowing date and cultivar interaction on germination percent demonstrated that Opera, Okapi x GA096 (5)(2) and GA096 x Zarfam (5)(1) each with mean of 100% had the most germination percent in all sowing date. Generally, results revealed that delaying in sowing date resulted to decreased germination percent. Result showed that cultivars and lines that had the highest germination percent also had the longest root and shoot length.

To investigate the role of mucilage in germination of medicinal plants in drought stress conditions, germination test conducted on 4 replications of 25 seeds of 13 species of medicinal plants with mucilage from the families of Lamiaceae, Brassicaceae, Fabaceae, Linaceae and Plantaginaceae in 9 cm diameter petridishes with filter paper premoistined with distilled water in the Seed Laboratory, Faculty of Agriculture, Ferdowsi University of Mashhad in 2012. Different levels of waterpotential (0, -0.1, -0.2, -0.3, -0.4 MPa) using PEG applied and germination percent and mean germination time (MGT) of the species were determined.Results showed osmotic potential levels had a significant effect on the germination percent and mean germination time (MGT) of the species (P≤0.01). P. psylliumM. officinalis and L. usitatissimum were tolerant while, S.officinalis,A.homalocarpum and P.major were sensitive species and other species showed moderate tolerance. It seems amount of the mucilage of species was effective on tolerance of the species. The positive effect of the mucilage on the reduction of stress in the majority of the species may have an ecological benefit in the harsh conditions for the germination of the species with mucilage.

This experiment was conducted to study the effect of different packages on oil rapeseed varieties produced in Qom province. The studied cultivars were RGS, Talaieh and Okapi and packaging cover types were three andndash;layer paper bag ,4-layer paper bag , propylene bag,propylene+paper and flaxen bag which was studied using factorial experiment on the basis of randomized complete block design in 3 replications. The seed containing bags were stored in the ware house of agricultural and natural resources center of Qom province for 1 year and standard sampling of each treatment and replication was done at the end of the storage period then seeds germination was tested. Also electrical conductivity test ,average time for germination cold test and accelerated aging test have been conducted for estimating seed vigor. The results showed no significant difference between cultivars and cultivars reaction to the exerted treatments was the same, but seeds storage in the various bags had a significant effect on seed vigor as seeds in four layer and three layer paper bags had the most vigor and seeds in propylene bags and paper propylene bag had the least vigour.Also the results showed that various seed storing covers have significant effect on the average time of seeds germination ,electrical conductivity and vigor after cold test and accelerated aging test and in all cases three and four layer paper bags showed the best resulting. However propylene and paper propylene bags had more deteriorating effect on seed quality. Since in the warehouse the temperature had increased up to 45anddeg;c and air relative humidity up to 85% in some months of the year, and with considering that high temperature may accelerate the incidence of some hydraulic reactions and either seed deterioration, so the temperature has more effect on propylene and propylene paper bags.