Journal of Horticultural Science
Year:2008 | Volume:22 | Issue:1|Papers Count:13

The CEL I enzyme, a technical glycoprotein associated with the S1 family of endonucleases, is the first eukaryotic nuclease known for cleaving DNA with high specificity at sites of base–substitution mismatch and DNA distortion. CEL I assay is a highly sensitive method for detecting both polymorphisms and disease-causing mutations in DNA molecules, with a wide range of applications to research and medical genetics. So far, this enzyme has been produced in native form by isolating it from celery tissues according to Yang et al., 2000, but it appears to be a complex and expensive method for obtain this valuable enzyme. In this research, with the aim of improving the efficiency of enzyme isolation, we are seeking the best CEL I producing cultivar of celery or a plant source better than celery to produce the enzyme. The expression of CEL I RNA was compared in some plants belong to the Apiaceae family using semi-quantitative RT-PCR. The expression levels of the cel I gene were investigated in 12 plants including 7 cultivars of celery and five of its relative species from the Apiaceae famuly. The differentiall expression of the cel I gene was observed in both different celery cultivars and the plant species. Although 5 celery cultivars showed the same expression level, 2 cultivars, GSB and Victoria, showed a some lower expression. Differentially expression of cel I gene was more obvious among different Apiaceae family plants where Anethum graveolens and Foeniculum vulgare, showed considerably higher levels of cel I gene expression than celery.

In this study, the effect of different concentrations of sucrose, maltose, glucose and fructose on induction of embryogenic callus and somatic embryos of one carnation cultivar (Nelson) were investigated. Embryogenic calli were produced on MS culture medium containing four concentrations of sucrose (30, 6o, 90 and 120 g/l-1) all supplemented with 2 mg/l 2,4-D and 0.2 mg/l BA. Maximum frequency of embryogenic callus was obtained from the media containing 9% sucrose. Somatic embryos were formed when embryogenic callus were transferred to MS medium without growth regulators containing 15, 30, 60, 90 and 120 g/l-1 sucrose, maltose, glucose and fructose. Normal embryos were not developed in the media containing 15 and 30 g/l-1 sucrose, maltose, glucose and fructose. Somatic embryos were transferred to half-strength hormone-free MS culture medium containing 30 gl-1 sucrose, were germinated into plantlets about %90. Plantlets also continued their growth under greenhouse conditions.

Sun drying is one of the most popular methods for agriculture product preservation. This research was mainly devoted to a nearly new approach for applying solar energy as the main source of energy for a cabinet solar dryer. This active solar dryer can be applied in two different modes namely indirect and mixed for drying fruit. For evaluating this solar dryer, grape was selected for drying in thin layers. In this research the effect of air flow rates and different modes of drying were investigated on moisture reduction trend for grapes. Uniformity of drying processes on trays was also evaluated. Tree levels of air flow rates (0.085, 0.126 and 0.171 m3/s), two modes of drying processes (indirect and mixed), five sampling spots on the lower tray, three samples on the upper tray and two samples on the trays were selected. The solar dryer was tested in Sep. and Oct. in agriculture engineering dept. Shiraz University. ASKARI (KHALILI) cultivar grape with an average initial moisture content of 78% (wb) was chosen. The moisture content of the products was reduced to an average of 15% (wb) within 4-5 day each from 10 to 16 o’clock with an average solar intensity of 870W/m2. Statistical analysis showed that both airflow rate and mode of drying application were significantly affecting the rate of moisture removal from the products. Uniformity of the dried products on the trays was also proved but the average moisture content of the grapes was significantly different.

In this study, effects of different concentrations of sucrose and silver nitrat, silver thiosulfat (STS), benzyladenine (BA) and their interaction on extending the vase life of cut carnation (Dianthus caryophyllus L. cv. Pink castellaro) was investigated. These chemicals had no considerable effects on decreasing of the rate of petal wilting but their interaction with sucrose brought about significant results. The concentration of 750mgl-1 silver nitrate plus 5% sucrose showed significant difference on decreasing of petal wilting after 6 days. The best results were obtained at the concentration of 25mgl-1 silver thiosulfate plus 5% of sucrose. Benzyladenin at the concentration of 25mgl-1 plus 5% of sucrose had a significant effect in comparision with the untreated control.

In order to select new cultivars of stock, excelling at ornamental traits, several lines of stock were crossed and the results were analyzed in next year. Parents were selected based on purity as the homozygous line at morphologic traits and crossing ability between parent lines (not incompatibility). Thus, Y3×RH, Pride3×Bd, F3×Rpd crossing were studied in the second year. The traits studied included: plant height, inflorescence height, number of leaves, number of florets, flowering period on plant, stem diameter, vegetative period, stem height, weight of 1000 seed, seed production and number of pods per plant. the correlation between these traits in 19 genotypes of stock were studied. self-pollination between 7 genotypes was successful only in IH and Y3 genotypes. greatest percentage of double flowers in Pride3×Bd. The highest inflorescence height among hybrids belonged to F3×Rpd. There was a significant difference between hybrids in plant height and the highest and lowest belonged to Y3×RH and Pride3×Bd respectively. The greatest value of heterosis in Y3×RH and F3×Rpd belonged to seed production and in Pride3×Bd belonged to flowering period on plant.  A significant positive correlation was found between plant height and inflorescence height and the number of leaves, number of florets, stem diameter and stem height. The number of leaves per plant was significantly and positively correlated with number of florets, stem diameter, vegetative period and stem height.

Low seed germination and seedling emergence is one of the main problems in saline areas. Selecting of salt-tolerance grasses is essential as a strategy for salt-soils remediation and using landscapes where irrigated by saline water. Seed priming technique has been known as a cause to improve germination and seedling emergence under different environment stresses. The objective of this study was to evaluate the effectiveness of seed priming in improving seed germination and seedling vigor of three species of perennial grasses including Agropyron elongatum, Bromus tomentellus and Hordeum bulbosum, in response to 7 levels of NaCl (0, 50, 100, 150, 200, 250 and 300 mM) under laboratory conditions. The best osmopriming treatments were determined based on a preliminary experiment included (A.elongatum; CaCl2, -1.5 MPa, for -2 d, B.tomentellus; CaCl2, -1.5 MPa, for 5 d and H.bulbosum; NaCl, -1 MPa for 5 d). This experiment was carried out as factorial experiment based on a randomized completely design, with four replications. The results showed that seed germination, germination rate and seedling vigor were significantly (P <0.01) decreased by increasing salinity for unprimed seed (control) compared with primed seeds. However, at severe salinity level (300 mM) seed priming enhanced germination percentage, germination rate, root length, shoot length, root dry weight and shoot dry weight 62.9, 39.0, 17.4, 10.4, 39.2, and 9.0 percent respectively. The response of grasses to salinity varied both A.elongatum and H.bulbosum were salttolreant than B.tomentellus. The results suggest that seed priming significantly increased salt tolerance of the grasses at germination and emergence stage by increasing germination rate, seedling growth and probably salt toxic decline. Also osmopriming technique could be effective for improvement of germination ability and seedling vigor of grasses at initial growth stages in saline areas.

In this research the effect of different concentrations of ammonium (0.0, 0.1, 0.3 meq/l) and molybdenum (0.0, 0.1, 0.15 mg/l) in nutrient solution on nitrate accumulation in greenhouse cucumber fruits was studied. Two cultivars Ruba-s and Sultan were planted and studied during two cultural seasons fall and spring and in every cultural time we have two harvests for sampling .The experimental design was factorial-split-plot with complete randomized design in two times. Results of statistical analysis showed that nitrate accumulation in plants fed by 0.3-meq/l ammonium was lower than those fed by 0.1 meq/l ammonium, but the lowest level of nitrate was observed in plants by solution had no ammonium. Among different levels of molybdenum the highest nitrate accumulation observed in plants that fed on by solution had 0.15-mg/l molybdenum. The two cultivars showed no significant differences in this character. Two cultural times and harvests were significantly different. The first harvest and spring culture had lower level of nitrate accumulation than other treatments.

Salinity is recently the major abiotic stress for plants because beside of crop rate, it causes restriction of water and useable land for agriculture. Many investigations showed that silicon decreased several stresses including salinity in plants. Therefore, an experiment was conducted using completely randomized design with 3 replications to determine the effect of silicon on lettuce growth as affected by highly salinity. Treatments were four concentrations of silicon (Si) levels (0, 0.5, 1.0, 2.0 mM L-1 as sodium silicate) added in modified Hogland solution Nutrient Film Technique (NFT) system. Electrical conductivity was increased by NaCl addition in all treatment. The results indicated that highest leaf surface as well as fresh and, dry weights of leaf and whole plant where obtained with 0.5 mM. L-1. Control had the highest whole plant dry matter and fresh and dry weight of roots. Increasing Si up to 1.0 and 2.0 mM L-1 reduced yield components. The results reported here indicated that application of silicon is recommend under in salinity stress.

In order to study the effects of calcium on tomato plants( Lycopersicon esculentom.v.mobile) germination grown under salt stress, an experiment was arranged as a factorial experiment, based on completely random design with three replications. The salt levels included NaCl solutions with electrical conductivity, 0, 6 ,8, 10and 12 dsm-1 . Calcium used as CaCl2 and CaSo4( 5 mM).The seeds were sowed in Petri dishes with 9 cm diameter. The germinated seeds were counted at fourth, sixth and eightth days after sowing, seed germination percentage and germination rate were calculated. Eight days old seedlings were harvested and their hypocotyle and radicle lengths were measured. Weights of hpocotyle and radicle were also evaluated. The results showed that seedlings growth were significantly inhibited (p£0.01) by all salinity levels, particularly in 10 and 12 dsm-1 NaCl. All of the above mentioned parameters showed progressive and significant decline with salinity increasing especially at 4th and 6th days after sowing. Cacl2 and CaSo4 in 5mM concentrations were significantly ameliorated these characters (p£0.01). The results of these experiments showed that cacium (CaCl2 and CaSo4 5 mM) had significantly effects on amelioration injury of tomato grown under salinity.