IRANIAN JOURNAL OF HORTICULTURAL SCIENCE AND TECHNOLOGY
Year:2009 | Volume:10 | Issue:2|Papers Count:11

The experiment was carried out to investigate micropropagation of sweetgum through organogenesis. For callus induction, explants (petioles) were cultured on WPM basal medium supplemented with different concentrations of 2,4-D (0.01, 0.1 or 1 mg l-1) and TDZ (0.01, 0.1 or 1 mg l-1). Although there was no significant difference among the media in callogenesis stage, a significant difference was observed in shoot regeneration stage. For callus regeneration, calli were transferred on WPM basal medium supplemented with different concentrations of NAA and BAP. The best concentrations of BAP and NAA for shoot regeneration were 0.5 and 0.01 mg l-1, respectively. The results showed that lower concentrations of the plant growth regulators were more effective for shoot regeneration in organogenesis. It can be concluded that high concentrations of the plant growth regulators significantly reduced shoot regeneration. WPM medium containing 1 mg l-1 NAA was the best for rhizogenesis.

The breeding program of Iranian table grapes has been started since 1996. In this research, four seedless grapevines as male parents, seven seeded grapevines as female parents and 12 superior progenies from their cross were used to study with microsatellite molecular marker due to certification of trueness of control cross and their results. The results of Dice similarity coefficient couldn't determine definite parent for some of progenies. To solve this problem, natural logarithm of likelihood ratios were used to calculate difference between most likely parent and next probable parent. Confidence and significant levels of those differences were evaluated by simulation at 95%. The highest similarity between a seed parent and its progenies was about 0.65 and belonged to 'Alibaba' cultivar and three S54, S55, S40 progenies. Male and female parents for each progenies were determined by maternity, paternity and parent pair analysis. Fractional assignment method was used when parents of offspring had shared genetic background. For the rest of the superior progenies, father and mother were determined and relationships between them were cleared too. In this study, microsatellite as a codominant marker could discriminate parents and progenies with use of assignment approaches. However, it couldn't be used to discriminate between 'Sultana' and 'Red- Sultana' as male parents and their offspring due to its high similarity. Results showed superior progenies had been hybrid. The relationship well distinguished among progenies as full and half sib. Likelihood based assignment reduced errors and determined parent of progenies.

The positive and beneficial effects of mycorrhizal symbiosis on the growth of various plants were previously documented. To realize the symbiotic association between mycorrhiza fungi and commercial native almond genotypes in Chaharmahal va Bakhtiary province, a factorial experiment consisted of a randomized complete design with three factors: almond genotypes ('Mamaei', 'Rabee', 'Talkh', 'Sefid'), soil phosphorus levels (0 and 150 kg P ha-1) and mycorrhizal treatment (almond inoculated with Glomus intraradices, Glomus mosseae and without inoculation) and three replications was conducted under greenhouse conditions for 4 months. Results showed that almond seedlings were able to establish a symbiotic relationship with endomycorrhizal fungi, and the mycorrhizal dependency is relatively striking. However, there were no significant differences among mycorrhizal species in affecting colonization percentage and plant growth. Mycorrhizal inoculation significantly increased plant growth (i.e. leaf area, plant height, stem diameter, root length, and dry and fresh weights), but the increase was not statistically significant in P-fertilized soils. The growth of mycorrhizal almond plants in low P soils had no significant difference with non- mycorrhizal plants in high P soils, suggesting high P availability may lower the effects of mycorrhizal fungi on almond growth.

The olive oil quality depends on different factors such as cultivar, climate conditions and the ripening stage. Amongst them, cultivar is one of the most important effective factors. In this experiment, the olive oil quality of 'Roghani' and 'Mari' cultivars was compared with the olive oil quality of 'Leccino', 'Kalamata' and 'Conservalia' cultivars in Roudbar region of Guilan province. Considering, the quality indices (acidity, peroxide, spectrophotometric indices of K232 and K270), fatty acids, composition, total phenol, chlorophyll pigments and the carotenoid of the oil of the cultivars under study were examined. Analysis of fatty acids by GC showed that the highest and lowest level of unsaturated fatty acid, oleic belong to the oil of 'Kalamata' (83.69%) and 'Mari' (75.99%) cultivars, respectively. Also, the lowest level of saturated fatty acid was palmetic that found in the oil of 'Kalamata' cultivar. The level of linoleic acid in the oil samples of all the cultivars was found to be lower than the range accepted by the International Council of Olive Oil. The level of total phenol as well as chlorophyll pigments and carotenoid showed significant differences among the oil samples of the five cultivars. 'Mari' and 'Leccino' cultivars showed the highest levels of chlorophyll and carotenoid. The highest and lowest levels of total phenol belonged to 'Roghani' and 'Conservalia' respectively. Based on the results of this experiment, it was observed that, in comparison with other cultivars, the olive oil of 'Kalamata' and 'Mari' cultivars had higher quality in Rudbar region. These differences in the olive oil quality of the cultivars under study were due to the differences in genetic factors during the process of fruit growth in each cultivar.

There is a species of barberry that cultivated in arid and semi arid area of Iran (south Khorasan province) which is widely used as a food additive for rice cooking. Fruits of this species have no seed while wild types at the same area produce seeded fruits. In this experiment, mechanism of seedlessness was evaluated by in 'in vitro pollen viability test, in situ, pollen tube growth study in pistil, histological study of ovule development and field pollination experiment. Histological study was done in seeded wild type barberry (Berberis crataegina DC) as well. In vitro test of pollen germination in seedless barberry showed that pollen had viability of about 54%. Seedless barberry produced 20% seeded fruit when pollinated with pollen of wild types barberry. There was dramatically decrease of fruit set in emasculated unpollinated flowers of seedless barberry. Plenty of pollen grains (about 370) were observed on stigma of each flower at 12 hr after flower opening. Most of them germinated and penetrated intracellular area of stigma surface but no pollen tube reached to ovary. About 41% of studied ovaries in seedless barberry did not have any embryo sac or had very small incomplete embryo sac. In seedless barberry, in some case unfused polar nuclei were clearly recognized at 14 days after anthesis. However, In wild type, double fertilization was accompanied by disappearance of polar nuclei. In seeded barberry, the cellular endosperm became clear at seven days after anthesis. At 21 days after full bloom, all ovules of seedless barberry degenerated while at the same time in wild seeded type, one or two ovules of each flower were normal and were developing toward complete seeds. In general, it can be concluded that self incompatibility have main role in seedlessness in barberry but high frequency of abnormal ovules and single fertilization can be considered as another reason of seedlessness. Fruit of seedless barberry is probably set via simulative parthenocarpy.

For evaluation of salinity stress effect on some ecophysiological traits including leaf scorch severity, chlorophyll index, amount of free proline, relative water and leaves ionic contents of selected genotypes of East Azerbaijan almond population (Prunus amygdalus B.) and accessibility of promising tolerant genotypes among them the experiment completely randomized design with three replicates and five salinity treatments including: (0, 25, 50, 75 and 100 mmol l-1 NaCl) was carried out. Salinity treatments were applied to two- year- old seedlings planted in regional typical soil. Results showed chlorophyll index and relative water content were decreased by the increase in the amount of salt significantly and linearly but free proline was increased under this condition (P£1%). Leaf analysis results also showed Na+ and Cl- contents were increased significantly with salinity (P£1%) whereas Mg2+ and Ca2+ contents had a deceasing trend but non significant. K+ content of the leaves was influenced by different salinity levels irregularly, but Na/K. and Na/Ca ratios were increased when the salinity level was increased. This research determined that leaf scorch threshold in experimented genotypes was in relation with an accumulation of Na+ between 9 to 11 mg g-1 dry weight.

Salicylic acid is the group of phenolic compounds which are found naturally in plants. These compounds also produce by soil microorganisms and plants. Salicylic acid will affect on growth and development and protect the plants against of environmental stress. In order to study of salicylic acid on Colza, plants were treated with four concentrations of salicylic acid (0, 0.5, 1 and 1.5 mM). Soluble sugars, reducing sugar in root and shoot, malondealdehyde, other aldehydes, ascorbic acid, dihydroascorbic acid, total ascorbate, protein and ethylene emanated by detached leaves were measured. Results showed that reducing sugar in root, ascorbic acid, dihydroascorbic acid and total ascorbate significantly increased in plants which were treated with lower than 1 mM salicylic acid. Salicylic acid increased malondealdehyde and other aldehydes but did not change the soluble and reducing sugars content in shoot. Ethylene emanation by those detached leaves which were significantly decreased treated with 0.5 and 1 mM salicylic acid but treatment with 1.5 mM salicylic acid increased that. It is now clear that SA in some plants provide protection against a number of environmental stresses but SA known as an allelopathic compound, which can cause stress in sensitive plants, e.g. colza cultivar 'Option'.