Showing 3 results for Temperature
R Ghafari, Fariba Meighani, F Ghasemkhani, H Salimi,
Volume 15, Issue 1 (4-2015)
Abstract
Abstract
Mesquite is one of the invasive, problematic and noxious weeds and special warm and dry areas. This plant in recent years due to high resistance to drought stress level in the vast agricultural lands and orchards spread. Management so it is very important. The following studies were conducted in plant protection of weed research Department Research Institute of during the years 2010: 1- Effect of constant temperature on germination that including 5, 10, 15, 18, 20, 25, 30, 35 and 40° C independent dark and independent light conditions 2- Effect of temperature fluctuations on seed germination: 0/10, 10/20 and 20/30° C 3- Effect of planting depth seed on seed germhnation. All experiments were conducted with 4 replications. mesquite seeds showed no dormancy when detachment from mother plant. Seed germination was strongly influenced by temperature. Light did not play a crucial role on seed germination of this weed. Therefore mesquite seeds were not photoblastic and temperature fluctuations did not increase seed germination of mesquite. The above characteristics are very important in making mesquite an invasive weed. Having precise information of these traits enables us to a better management and control of this troublesome weed.
Keyword: Prosopis farcta, seed germination, seed dormancy, constant and fluctuating temperature, planting depth.
F Masoodi, F Naderi,
Volume 16, Issue 42 (5-2015)
Abstract
Aliabad Damagh region in southern Hamadan, is located NW of Sanandaj Sirjan Zone. In this region, different metamorphic rocks with a variety of fabric elements are exposed. In this research, metamorphic rocks were investigated based on the microfabric and temperature. In the area deformation occurred along the temperature variations path. Three generations of foliation and four deformation phases are present in the region. Porphyroblasts growth in foliation and microfabric evidence reveal that deformation began during regional metamorphism, while mica and chlorite crystallized as post tectonic minerals compare to S3 during retrograde metamorphism. The highest grade of this metamorphism is green schist to amphibolite facies.
Deformation elements in granite mylonite and metamorphic rocks in Aliabad Damagh region imply occurrence of regional metamorphism followed by a dynamic metamorphism which cause a widespread ductile shear zone. Deformation elements in carbonate mylonites, confirm the presence of a right lateral shear zone. Based on calcite twinning in mylonitize marbles the temperature of dynamic metamorphism is higher than 200 ˚C. Based on the effect of temperature on lithology, fabric and strain rate, the shear zone in Aliabad Damagh region is ductile to brittle.
Volume 18, Issue 49 (11-2006)
Abstract
222 prespawning adult Acipenser persicus including 178 female and 44 male were sampled for studying the effect of temperature on the artificial breeding in the southeast of the Caspian sea during march 2000 – May 2001. The samples breeded in the shahid Marjany, sturgeon breeding and propagation center in Gorgan. In this study, the effect of temperature on fertilization percentage, the time of female sex ripering, positive feedback of broodstock to injection of pituitary studied. To study the effect of temperature on fertilization percentage, the time of female sex ripering, temperature groups divided into three groups and also to study the effect of temperature on the positive feedback of broodstock to injection on pituitary the temperature groups were divided into four groups. The highest fertilization percentage observed in 16.1-18°c. Increasing the temperature declined the time of female ripering of sexual maturity and positive feedback to pituitary injection
