جستجوی مقالات مرتبط با کلیدواژه « یزد » در نشریات گروه « بیوتکنولوژی و ژنتیک گیاهی »

This study aimed to estimate the genetic parameters of Haloxylon ammodendron located in the seed orchard of Yazd province, Iran, using REML method and repeatability model. For this purpose, among the stands of black saxaul in Yazd province, several rootstocks with suitable appearance, desirable quality, the relative balance between crown and trunk, resistance to pests and diseases selected and their seeds were sown in nursery, and the seedling were planted in the field based on a completely randomized design with unequal replications, 6 to 20 seedlings. The genotypes of each rootstock were planted on rows at 6-m intervals. Data collected and genetic parameters estimated for seedling traits as tree height, canopy expansion, trunk diameter, number of sub-branches, and freshness. Data were analyzed of variance using REML method, two different repeatability, and non-repeatability models. The results based on both models showed that the highest heritability was related to tree height. But these estimates between two methods were different so that, the genetic correlations and heritability values in the repeatability model were significantly lower than that for non-repeatability model. Repeatability was estimated based on the intragroup correlation between two independent variables on individuals and expressed as the ratio of differences between individuals to the existing phenotypic differences. Based on the results, the repeatability of the most traits was high. This result enables breeders to make good decisions about keeping rootstocks in the seed orchard during the growth stage in the early years. Finally, it was concluded that the repeatability model, could estimate moderate heritability for all of traits, which is more in line with the reality and quantitative nature of the studied traits and they could be mare affected by the environment factors.

Vegetation cover is one of the most importantfactors for ecosystem sustainability. Thus, recognizing factors that result in establishment and distribution of vegetation is crucial. This study was carried out to determine the relationship between plant associations and some soil properties in Bahadoran Kalmand protected region. Soil features of plant associations including texture, EC, PH, SAR, Cations, Anions, and OCs were measured and data was analyzed using Principal Component Analysis. The results indicated that, in addition to climatic factors, the plant associations distribution pattern was mainly affected by soil characteristics including EC, PH, texture, and SAR. Generally speaking, depending on habitat conditions,ecological needs, and tolerance, each plant association shows different resistance toward environmental factors and soil properties.

This study was carried out in an attempt to determine and introduce the best accessions of the cultivated Thymus Lancifolius with respect to the quantity and quality of the essence. After cultivating 10 different accessions of Thymus Lancifolius species at the Medicinal Plant Research Center of the province in Gordfaramarz Shahediyeh Yazd, from the second year, the aerial parts of the plant were collected at 50% flowering stage and, after being dried in shadow through hydro-distilled strategy, the essence was extracted. Once the essential oil yield was determined based on the dry weight of the plant, the essence was decomposed and identified by means of GC and GC/MS. The results of cluster analysis of the main 10 oil components indicated that there were four groups in which geranial (T1, T5), linalool (T3, T9), thymol (T2, T7), carvacrol and thymol (T8), trpineol and thymol (T6), limonene and thymol (T10), and geraniol and thymol (T4) were dominant components of essential oil in accessions. Considering the oil yield, the production rate, and the composition of the essential oil, the accessions of TL9 originated from Markazi province with 40% of essence and production rate of 36.35 kg/hectare and 81.4% linalool; the accession of TL4 with 2.55% essence, the production rate of 34.82 kg/hectare, and 20.5% thymol; and the accession of TL2 with 1.42% essential oil, the production rate of 28.4 kg/hectare, and 68.4% thymol were selected as the best accessions of Thymus lancifolius.

To investigate possible effects of seed source and genotypes on germination rate and several other morphological traits on seedlings of Acer monspessulanum subsp cinerasens, seeds were collected on 20 genotypes of two populations (2400 and 2700 meters above sea level) of the species of Chenarnaz forest, located in South part of Yazd province, Iran. Seeds were planted in a research greenhouse at Yazd University based on a completely randomized design with three replications. Analysis of variance showed that effect of altitudes of seed sources on collar diameter, root length and fresh weight of seedling root were statistically significant, so that, collar diameter and root length of seedling from the studied plant population at 2700 meters above sea level, were better than that of the second plant population. Although according to the studied characteristics of the population at altitude of 2700 meters the studied population was identified as a suitable plant population for seed collecting, seedling production, reforestation and subsequently recovery of degraded areas, but much less percentage of the stands at the altitude of 2400 meters could also be considered in order to maintain genetic diversity. Thus, on both plant populations, the best trees were identified in terms of the studied traits value. It is recommended that special attention be paid on the mentioned trees for seed collecting.

The Satureja genus belongs to the family of lamiaceae and consists of over 235 different species all over the world. Fourteen species grow naturally in Iran of which nine species are endemic. Different species of Satureja are used in food, health, cosmetic, and medical industry. This research was carried out for identifying and introducing the most suitable Saturejasahandica accessions in medicinal plants research station in Gerdefaramarz city of Shahediah, Yazd province, with the coordinates of longitude and latitude of 55 31 49N and 27 15 54E and a height of 1209 meters above the sea level. The seeds of eight accession of saturejasahandica were planted in jiffy pot in the green house of the research center. Once the seedlings made enough growth, they were taken to the farm and planted. The experiment was conducted in a randomized complete blocks design with three replications. The degree of plant establishment, canopy diameter, plant height, yield, essential oil yield per hectare, and percentage of essential oil were measured and recorded. On the basis of the results of the analysis of variance, dry weight of shoot, rate of plant establishment, plant height (p