نشریه بوم شناسی گیاهان زراعی
سال یازدهم شماره 3 (پیاپی 41، پاییز 1394)

This study was conducted in a split plot based on a completely randomized block design with three replications in Research Farm of Islamic Azad University to investigate the reaction of white bean cultivars under drought stress condition. Drought stress condition consisted of two irrigation intervals including 5 and 10 days as the main plots and five cultivars of white beans including Marmar, Yas, Sadaf, Daneshkadeh and 11805 were placed in subplots. Limited irrigation condition caused significant reduction in most of the studied traits and the yield of all studied cultivars decreased significantly. Among the studied cultivars, Sadaf, Daneshkadeh, and 11805 had the highest yield and were identified as the cultivars susceptible to stress. There was a positive and significant correlation between the indices of stress susceptibility, geometric mean productivity and stress tolerance index under optimum and limited irrigation and their yield. Therefore, cultivars with high geometric mean productivity and stress tolerance index and low stress susceptibility index were identified as cultivars tolerant to limited irrigation.

To exchange the genetic materials and germplasm and their evaluation in international level, International Rice Research Institute is releasing hybrid rice promising a few cultivar and lines every year in some countries. This experiment was sent at Rice Research Institute of Iran and laid out in augmented design in two locations (Rasht and Amol). During growth stages some traits such as plant height, tiller number, days to 50% flowering, 100 grain weight, panicle weight, yield and vigor of seedlings were recorded based on standard evaluation system of rice. In Amol, two hybrids (IR80126H and IR80126H) and four restorer lines comprising IR63864-147-1-3-24R, IR69724-126-3-3-2-3R, IR71604-4-1-4-2-3-2-3-2R, IR72102-3-135-1-1-2R were selected because of their suitable phenotypes, high panicle weight and yield and the restorer lines were added to restorer nursery. In Guilan, hybrids such as IR80117H, IR80127H and IR76708H in cause of yield and early maturity were selected and three restorer lines such as IR60199-B-B-2-1R, IR71604-4-1-4-2-3-2-3-2R and IR72102-3-135-1-1-2R were added to parental nursery. Also all of raw data were recorded in the field book and were sent to International Rice Research Institute.

In order to investigate the effect of different amounts of potassium and manganese on qualitative and quantitative yield and other traits of sugar beet in the northern of Khuzestan, a split block experiment was conducted based on complete randomly block with 12 treatments in three replication in fall cropping season October 2013-2014 in farmland of Haft Tapeh area of Susa city. A resistant mono germ genotype with high yielding named Spartak was used in this study. Examined factors included employing potassium fertilizer treatment in four levels of 0, 1, 2 and 3 kg/ha and manganese fertilizer in 0, 1, 2 kg/ha rates. Spraying with potassium fertilizer had a significant effect on root and white sugar yield. The highest root and sugar yield in treatment were achieved with 3 kg/ha of potassium fertilizer with 80.6 ton/ha root yield and 13.63 ton/ha white sugar yield. Using manganese fertilizer hadn’t significant effect on root yield and other studied traits. Also, using different rates of potassium and manganese fertilizers did not have much influence on qualitative characteristics of sugar beet such as nitrogen, sodium and potassium amounts in root, sugar extraction coefficient, molasses percentage, raw sugar and white sugar percentage. On the whole, using potassium and manganese during the vegetative growth stage of sugar beet is recommendable.

The seed of some medicinal plants has different kinds of dormancy which is due to ecological compatibility with a variety of environmental conditions. Therefore, identification of the effective ecophysiological factors affecting dormancy and creation of optimal conditions is essential for seed germination of medicinal plants for their cultivation and production. An experiment based on a completely randomized design with five treatments and four replications was conducted to evaluate the effect of different treatments on Alyssum homalocarpum seed germination. The treatments consisted of soaking seeds in potassium nitrate 0.2 and 0.1% for 48 hours, tap water for 24 hours, carbonyl diamide solution (urea) for 48 hours and distilled water (as control). The highest germination percentage (88%) and speed (0.92 seeds per day) of germination resulted from tap water treatment was available for 24 hours. Soaking seeds in water causes the reduction of mucilage formation around A. homalocarpum seed and significant increase of the germination percentage and speed. On the whole, seed dormancy in A. homalocarpum species is of physiological type which is due to the presence of inhibitor factors on the skin or in the embryo sac. Therefore, the most appropriate and effective treatment for breaking physiological seed dormancy in A. homalocarpum species was soaking the seeds in tap water for 24 hours.

Effects of sowing date and water deficit were studied at different reproductive growth stages on some qualitative and quantitative characteristics of sunflower cv. Azargol in Sistan, Iran. The experiment was carried out using a split plot experiment based on a completely randomized block design with three replications at the Research Station of Zahak in 2010. There were three levels of sowing times (2010/03/15, 2010/03/24, 2010/04/04) as main-plots, and irrigation levels (normal irrigation, water withhold at budding stage, 50% in flowering and grain filling stages) as sub-plots. The interaction between planting date and water withhold on all traits were not significant. The effect of water withholding different growth stages on grain yield, oil content, grain number, grain weight, were statistically significant at the 1% probability level. No significant difference was observed among treatments in water withhold and oil yield. The effect of planting date on head diameter, grain number and grain weight was significant at 5% level so that the lowest value measurement of head diameter, grain number and grain weight was the third planting date. Withholding irrigation had a negative impact on grain yield and oil percentage. According to the result of the research, 15 and 24 March would be recommended as proper planting date in this region.

In order to evaluation of effect of physical treatments on growth and effective ingredients of ribwort plantain (Plantago lanceolata) laboratory, green house and field experiments were performed in Islamic Azad University, Tabriz Branch, Iran during 2014 in three replications. Treatments were ultrasonic wave, laser, magnetic field, gamma and beta irradiations for 5, 10 and 15 minutes on wetted seeds included control. Seeds under magnetic field for 5 and 10 min. germinated after 11 days, while seeds under ultrasonication and laser treatments germinated after 13.2 days. Treatments studied lead to significant decrease in time to taken to 50% of emergence of seedling and mean emergence time compared to the control. Final emergence percentage in seeds under magnetic field and ultrasonic wave were 73.7%, but only 58.7% from seeds treated under gamma and beta irradiations. With increasing of exposure time of magnetic field seedling vigor index reduced significant. Seed yield in those seeds under magnetic field increased 8.5 g m-2 compared to mean of control, ultrasonic wave and laser. Seed turgidity index ranged from 0.77 mL in gamma and beta irradiations up to 1.47 mL in magnetic field treatments. Regression analysis revealed that the role of final emergence percentage and seedling vigor index in seed yield explanation were 1.8 and 1.7 times greater than time to taken to 50% of emergence of seedling, respectively. In ribwort plantain with treatment of seeds under magnetic field farmers could improve seedling vigor and increase yield and effective ingredients.

The Xanthomonas genus is one of the most important groups of plant pathogenic bacteria that cause post-harvest spoilage. Substantial crop losses may result from the rapid spread of the bacteria under favorable conditions, lack of seed germination, seedling death and vascular obstruction of plant. The aim of this study was to investigate the combined effects of different concentrations of Cuminum cyminum essential oil (EO; including 0, 0.2, 0.4 and 0.8%), three levels of acidity (5, 6 and 7), two inoculums’ level (103 and 105 CFU/ml) and two incubation temperatures (26 and 28˚C) on the growth of X. campestris in the nutrient broth medium in a completely randomized design with three replications. Growth was monitored by visible turbidity during a 30-day period. The minimum inhibitory concentration and minimum bactericidal concentration of EO against X. campestris was 1 and 2% respectively. According to the results, P-cuminaldehyde was the main component, with a content of 30.5%. The statistical analysis of data showed that the maximum time to detection of bacteria (19 days) in the concentrations of 0.8% EO, pH of 5, the inoculum level of 103 CFU/ml and incubation temperature of 26˚C and the minimum time to detection (16 hours) in the inoculums level of 105 CFU/ml, pH of 7, 28 ˚C and no EO was observed. In addition to the concentration of Cuminum cyminum EO as an antimicrobial agent, acidity of medium is also considered the factors influencing the growth of X. campestris. By decreasing the pH, the time-to-detection of bacteria was increased. In conclusion, using a combination of different factors can inhibit the growth of bacteria, significantly.

Mallow (Malva silvestris L.) is a valuable medicinal plant which its flower and leaf are mentioned in many pharmacopoeias as drugs with therapeutic properties. The study was conducted based on a completely randomized design with three replications to evaluate the effect vermicompost different rates on morphological characteristics and yield components of mallow in pot conditions in 2014. Treatments were five rates of vermicompost (0, 5, 10, 15 and 20 g/kg). In most of traits such as crown diameter, petiole fresh and dry weight, the root spread width, leaf number, canopy diameter, petiole length, plant dry weight, root fresh and dry weight, leaf width and length vermicompost 15 g/kg showed the greatest increment. However, application of vermicompost in 20 g/kg had better effect on leaf fresh weight. In plant fresh weight, vermicompost 15 and 20 g/kg had better effect. Vermicompost positive effect might be due to the structural characteristics and the presence of nutrients which could improve soil physicochemical properties and a positive effect on mallow growth. Using of sole bio-fertilizers or in combination with chemical fertilizers could have positive effect in medicinal plants cultivation.