جستجوی مقالات مرتبط با کلیدواژه « tetraploidy » در نشریات گروه « زراعت »

Eggplant (Solanum melongena L.) is an economically important crop with a wide range of fruit shapes and colors. Breeding programs in eggplant focus mainly on fruit quality. Production of commercial triploid cultivars and emission of seeds in fruits may increase acceptability by consumer and increase fruit quality. Induced tetraploidy and cross between di and tetraploid parental line is a conventional method used in different fruits and vegetables like watermelon. The current study aim to find how may induced tetraploidy affect pollen grain quality, its fertility, seed and transplant vigor in different eggplant cultivars. Aiming to investigate autotetraploidy in four qultivars of Solanum melongena L., Keshtzar, Yalda, Chahboland and Passargad on fertility, number of days till fruit-set, germination rate and percentage and successful transplanting percentage, a survey was done in a completely randomized design. Tetraploid plants were derived from seed maceration/shoot tip treatment (0.5, 1 and 2 percent of colchicine). To ensure ploidy level, chromosome counting of root tips and flow-cytometry was done during the experiment. To quantify germination percentage and rate, 15 seeds of each cultivar in each ploidy level were placed in petri-dishes in three replications. The seeds of each ploidy form were sown in seedling trays and after seedling period, plugs were transplanted in field for evaluation of characteristics in different ploidy levels. Growth and development rate of plant in seedling stage observed since seeds were cultivated. As soon as hypocotyl appeared on the surface, they were counted. Then seedling emergence and rate were calculated. To test viability of pollen grains, they were stained using acetocarmen. In order to find best parental lines, 18 plants from each cultivar and in each ploidy level were cultivated in the greenhouse condition in three replications. Then all plants were crossed competley (direct and reciprocal). Di and tetraploid plants were tested to find out which one would be better as which parent. Number of days till fruit-set, characteristics of seed and seedling and growth rate in seedling stage were significantly (P≤5%) influenced by changes on levels of poloidy. Pollen grain staining with acetocarmine for evaluation of fertility percentage in pollen grains showed that with an increase in ploidy level, fertility may significantly increase (P≤5%). In an effort to triploid plant production, none of the crosses between di and tetraploid plant could bear fruit. With the overall results, despite slower growth, can be tetraploid plant, due to improved germination and seedling emergence, survival and reproductive capabilities, higher transplanting success in this category of plants, induced increase in the number of chromosomal bundles can be considered as a good way to create genetic variation and prepare parental lines with desirable traits for use in the breeding programs.

Henbane lattice (Hyoscyamus reticulatus L.)¡ is one of the most important medicinal herbs of the solanaceae family which due to having Tropane alkaloids¡ frequently used in medicinal industry. Medicinal plant Regeneration¡ proliferation and In vitro ploidy induction are one of the interesting issues in biotechnology and plant tissue culture. This study was arranged as a completely randomized factorial design with Two Factors¡ BAP in three levels (0¡ 4.4¡ 8.8 µM) and IAA in three levels (0¡ 1.1¡ 2.2 µM) with three replications. Then¡ In vitro polyploidy induction in regenerated plants was surveyed by 5 different concentrations of colchicine at (0.00¡ 0.05¡ 0.1and 0.2 %) at various exposure times (24¡ 48 and 72 h). in order to determining plant ploidy level¡ microscopic¡ flow cytometry and chromosome counting were performed. The results showed that after six months; the best results (13.13 plantlet in each explants) were obtained in 8.8 µM BAP combined with 2.2 µM IAA. Flow cytometry study results showed that highest polyploid plants (72%) were obtained in 0.1% colchicine with 48 h exposure times. Polyploidy induction was associated with significant changes in plant characteristics. The chromosome number of diploid plants was 2n = 2x = 34 and in tetraploid plants was 2n= 4x =68. Therefore¡ can say that colchicine effectively induce polyploidy in the plant.

Chromosome manipulation of the plant species for development of genetic variation in morpho-physiological characteristics is a powerful tool in plant breeding. This experiment was conducted at Mohaghegh Ardabili university, Iran, in 2013 to induce tetraploidy in sorghum seed, seedlings and terminal buds of sorghum were treated with colchicine (0.025, 0.05, 0.1 and 0.2%) for 8, 24 and 48 hours. Determination of tetraploid plants was done through the morphological, stomatal and karyological studies. The 0.025% of colchicine for 48 hours and 0.1% of colchicine for 24 hours were the effective treatments for production of tetraploid plants in all treatment. Comparison of diploid and tetraploid plants showed that tetraploid plants had less stomata number but with greater size. Thickness of leaves, plant height, leaf length and width, stem diameter, number of leaves and panicle length and diameter were also higher in these plants. In addition, tetraploid plants had fewer or equal node number with diploid plants, but longer internodes. The chlorophyll, carbohydrates, total soluble protein content of leaf and antioxidant enzymes activity were significantly greater in tetraploid plants. The protein expression patterns studied by SDS-PAGE represented an increase in density of the protein bands in tetraploid plants as compared with diploids. In conclusion, polyploidy induction can be effectively employed in improvement of some morpho-physiological traits in sorghum.