جستجوی مقالات مرتبط با کلیدواژه « درجه روز رشد » در نشریات گروه « زیست شناسی »

Allium jesdianum is an endemic species of Iran that unfortunately, in recent years due to uncontrolled harvesting, had put it on to the endangered list. This research was carried out based on nested design with three replications from eight habitats including; Gamasiab, Kakareza, Peresk, Zalaghi, Venaei, Meleh, Serenge and Kamandan in the Lorestan province for two years. The results showed that Venaei habitat had the highest fresh (10.65 g) and dry weight (4.1 g). Soil texture of this habitat was Sandy clay loam and higher organic matter and potassium content than other habitats. The highest plant height (41.16 cm) was recorded in kakareza in the first year. The Soil of this habitat rich in phosphorus. Phenological growth stages (vegetative growth, flowering and seedling) of Allium jesdianum in Mela habitat, located in south of the Lorestan province was earlier than other habitats. The results showed that the time calendar and the time duration of the phenological stages were different in habitats. The growth degree days (GDD) was for the seeding stage was more than the other phonological stages and the highest GDD for this stage recorded in Kamandan, Azna (129.2 ºC) in the second year. The results of this research can be useful in proper management, breeding and domestication of this rare and endangered species.

Salvadora oleoides is a shrub or small tree, ever green or semi deciduous is extended in arid and warm regions of India, Pakistan and south east of Iran. In order to survey some phenological Phenomens with climate and physiographic properties, this study was carried out in the south-east of Iran from 2008 to 2011. In first step, distribution of species was recognized in Baluchestan province, and then 6 habitats were chosen. These habitats were visited in 2-3 week intervals annually. Three trees were marked in each site and were monitored during four seasons and its phenological stages were recorded. Climatic data were gathered and phenological stages were analyzed. The results of phenological and Meteorological data indicated that the growth patterns of Salvadora oleoides may alter with annual temperature and precipitation, distribution of rain and height of sea levels. Salvadora phonological stages are long term and vary 138-148 days in different regions. Buds begin to sprout in February to March and flowers appear in March. Round and green fruits appear on young branches in April. Fruit ripening start in June and fruits are starting to drop in July. In mountain regions, beginning of phenology is done 1 to 2 weeks after another sites. In eastern habitats (near to Pakistan) phonological stages occur in spring and fall. But raw fruits and flowers starting to drop when temperature decreases in autumn. In all conditions, amount of Growth Degree Days (G.D.D) required for ripening fruit is the same and equal to 1500ú C.