مجله علوم و فنون باغبانی ایران
سال پانزدهم شماره 2 (تابستان 1393)

In general, Cedrus spp.are difficult to root. Propagation of gymnosperms such as cedrus by cutting is difficult, because gymnosperms have poor root production efficiency. The present study was therefore carried out to investigate the effects of indole-butyric acid (IBA) and Zinc Sulphate (ZnSO4) on adventitious roots formation in semi-hardwood cuttings of Cedrus deodara Roxb. The collected cuttings were the first treated with different IBA concentrations (0, 3000, 6000 or 9000 mg l-1) and after two days, they were sprayed with ZnSO4 (0 and 5000 mg l-1). Treatments were performed three times at weekly intervals during experiment period. The lay out was as factorial completely randomized experiment design, with three replicates and 12 cuttings per replication. The callusing and rooting percentage, number of roots, length of roots, fresh and dry weight of roots and number of leaf orders on cuttings were recorded after 6 months. Rooting percentage significantly improved by zinc sulphate spraying compared to control. Treatment of cutting by IBA and zinc sulphate had significant effect on rooting efficiency. Higher number of roots, rooting percentage, fresh and dry weight of roots was obtained at 6000 mg l-1 IBA+ 5000 mg l-1 ZnSO4, compared to other treatments. The highest concentration of IBA (9000 mg l-1) had the lowest effect on rooting percentage (33.33%), while 55.6% rooting was recorded in cuttings treated with 3000 mg l-1 IBA.

Effects of salicylic acid and sodium nitroprusside (as nitric oxide donor) on physiological characteristics of tomato fruits during storage (temperature 12±1 ºC) were investigated. Tomato fruits were treated with salicylic acid (0, 0.1, 0.2 and 0.4 mmol l-1) and sodium nitroprusside (0, 20, 50 and 100 μmol l-1). Total soluble solids, titrable acid, vitamin C, total phenolics, total flavonoid and total antioxidant activity were evaluated over storage period. The results showed both salicylic acid and sodium nitroprusside increased total soluble solids, titrable acid, vitamin C, total phenolics and total antioxidant activity significantly over storage period. Salicylic acid and sodium nitroprusside had greatest effect on total soluble solids, total flavonoids, total phenolics, vitamin C and total soluble solids, total flavonoids and vitamin C, respectively. It was also concluded that postharvest treatment of fruit with the salicylic acid and nitric oxide is an appropriate method to improve quality traits of tomato fruits cv. ‘Falkato’ in storage.

Cumin (Cuminum cyminum L.) is known as most important cultivable medicinal plant in Iran. This research was aimed to study the effects of sowing date on yield and essential oil content of cumin ecotypes. The experiment was conducted as split plot arrangement in a compeletly randomized block design with three replications on growing season of 2011 2012 in Agricultural Research Station of Kerman University. Different sowing dates were 26th December, 10th January, 25th January, 9th February and 24th February, and different cumin ecotypes consisted of Semnan, Fars, Yazd, Golestan, Khorasan-Razavi, Khorasan-Shomali, Khorasan-Jonoubi, Esfahan and Kerman were used as main and sub plots, respectively. Different agronomic traits, yield and essential oil content were measured. Effects of different sowing dates were significant on all traits except for the number of seed per plant. Ecotypes showed significant variations for all studied traits. The interaction of sowing dates and different ecotypes was significant for all the traits except for 1000-seed weight. Change in rank interaction was observed for some of the traits, which represent different response of ecotypes to different sowing dates. Calculated GDD for each ecotype also demonstrated the different thermal requirements of them. Therefore due to the large variability in cumin germplasm, it is necessary to find the sowing date, for each ecotype, according to the environmental factors and the cultivation aim. The results revealed that based on cultivation aim, for getting the highest seed yield, sowing of Kerman ecotypes in February and for getting the highest essential oil percent, early sowing dates of Kerman and Semnane ecotypes, can be recommended for Kerman.

An experiment was conducted to test whether paclobutrazol application methods, time of application and concentrations would protect cucumber transplants against transplanting shock and water stress. A randomized complete block design experiment with four application methods (seed soaking, soil drench, spraying and root dipping) at three rates of paclobutrazol (0, 25 and 50 mg l-1) in factorial combinations was used. Half of potted plants grown under greenhouse conditions were subjected to drought by withholding irrigation and then were reirrigated. Results showed that except for root dipping treatment, other application treatments reduced height of plants. Non-paclobutrazol treatment significantly decreased leaf relative water content of deficit irrigated plants but in other treatments there were no significant differences between deficit irrigated and normal irrigated plants. It seems that paclobutrazol was most effective in improving resistance of plantlets to wilting after transplanting when applied at 25 mg l-1 using soil drench method and pretransplant paclobutrazol application to soil (drenching) at 50 mg l-1 can be useful on ameliorating water stress.

‘Washington Navel’ is one of the most important citrus cultivar. It is one of the earliest ripening, with high quality charcters and excellent market acceptance. This study was to examine the effects of 24- epibrasinosteroid on some characteristics of ‘Washington Navel’. In this regards, an experimental in a randomized complete block with three replications used to investigate the effects of various levels of brassinosteroid (0, 0.01, 0.1 or 1 μM) in three stages (after fruit set, after fruit set + a month before harvest and one month before harvest) After fruit harvest, 12 fruits from each treatment were stored at 4°C for 5 weeks. Then some characteristics were evaluated. The results showed that the application of brassinosteroid significantly improved the some characters such as: fruit firmness, skin thickness, organic acid, ascorbic acid, pH, soluble solids, skin ion leakage, phenol, percentage of weight loss and volume loss during storage. Also brassinosteroid increased antioxidant compounds such as ascorbic acid and phenols during storage, and increased tolerance to stress.

This experiment was conducted to determine the best rootstock for ‘Washington Navel’ orange. Nine selected strains of ‘Washington Navel’ were budded on three rootstocks including; Sour orange (Citrus aurantium), Citrange [(Poncirus trifoliata (L.) Raf × C. sinensis (L.) Osbeck)] and Trifoliate orange (Poncirus trifoliata (L.) Raf) in Astara Research Station. This experiment was carried out as a factorial in a randomized complete block design with 27 treatments and seven replications for five years. Results showed that cumulative yield per tree, yield efficiency and TSS were significantly higher on the Trifoliate orange rootstock. The largest cumulative yield per tree, and yield efficiency were observed on the B, F, I and E strains and the lowest were observed on D strain. The higher yield per tree was on the B, F, I and E strains when trees were budded onto the Trifoliate orange rootstock. The lowest alternate bearing index observed on E strain on Citrange and Poncirus rootstocks. The lowest yield and the greatest alternate bearing index were recorded C strain that budded onto the Citrange rootstock. Height, width, and canopy volume of trees were not affected by treatments. The greatest trunk to scion ratio was on C strain onto the Trifoliate orange and the lowest ratio was on G strain on Sour orange. Cluster analysis based on total measured treats was grouped strains in two main clusters and B, F, I and E strains were in one group. The combination of B, F, I and E strains on Trifoliate orange rootstock is advisable in this area.

Medicinal chavil plant (Ferulago angulata (Schlecht) Boiss) is an important plant belonging to the Apiaceae family, which has abundant economical usage. In order to micropropagate and to optimize in vitro chavil plant growth and development conditions two separate experiments were conducted. In the first the effect of different growth regulators combinations of BAP and IBA, NAA and Kin and control (medium 1/4 MS) on embryo culture was investigated. To optimize micropropagation conditions, in the second experiment two explants including crown and terminal bud, different concentrations of BAP and NAA were treated. For rooting plantlets, IBA and NAA and control (MS medium) treatment, were used. Shooting experiment was arranged as factorial using completely randomized design with three replications. The results of the first experiment showed that adding different growth regulators had negative effect on plant growth and development. The results of second experiment showed that crown explants has better response to shooting than terminal bud and the best combination of growth regulators on shooting was 2 mg l-1 BAP with 0.15 mg l 1 NAA in the case of all measured traits. Only 0.5 mg l-1 IBA generated roots among rooting growth regulators. In general, results of this investigation showed successful response of chavil plant to in vitro culture and micropropagation.

Fruits softening and weight loss during cool storage are the major limiting factors of postharvest life in ‘Hayward’ kiwifruit. In this study, effect of summer pruning at two times, 2 days or 15 days after petal fall, alone or in combination with %1 calcium chloride spray on fruit storage quality of ‘Hayward’ kiwifruit was investigated. Calcium was applied at 90 days after petal fall with 15 days intervals at four times. The harvested fruits were stored at cool storage at 1ºC and 90% relative humidity for 3 months. The results showed that fruits harvested from the pruned vines and treatment with calcium had significantly higher dry matter and calcium contents, but lower magnesium and K/Ca, N/Ca, K+Mg/Ca and N+K/Ca ratio as compared to control. These fruits showed higher flesh firmness, vitamin C content and titratable acidity, but lower weight loss and respiration rate. Furthermore, there was a positive correlation between fruit calcium content and dry matter at harvest time with fruit firmness and vitamin C at the end of storage. However, negative correlations were observed between fruit calcium with weight loss and magnesium content. Overall, summer pruning and calcium application could maintain postharvest quality of ‘Hayward’ kiwifruit by improving mineral elements balance and increasing fruit dry matter.

Melon (cv. ‘Semsuri’) is widely cultivated in Iran and therefore increasing the fruit yield and quality is necessary. Some growth regulators including 6-Benzylaminopurin (BAP) may affect plant growth and development. In two field trials, impact of BAP was studied on growth and fruit yield of melon. In first experiment, growth parameters of plants were recorded after 10 days of foliar treatment (6-7 leaf stage) with 0, 10, 20 and 40 mg l-1 BAP. In second experiment, plants were foliar sprayed with BAP at two growth stages (6-7 leaf and after fruit set stages). In both experiments, 40 mg l-1 BAP was most effective when compared to control, one spray increased relative water content, chlorophyll index, plant fresh weight, rind firmness and fruit yield by 16, 24, 26, 5 and 22%, respectively. High correlation coefficients were observed between fruit yield and other growth parameters recorded, so it may be concluded that fruit yield can be improved by promotion of growth parameters.

In the recent years, Lilium cut flower production has become very important among ornamental plant growers in Iran. Proper fertilization is a major factors affecting Lilium flower quality. In this study, the effect of different concentrations of potassium silicate, nanosilicon and calcium chloride were investigated on the quantitative and qualitative characteristics of Asiatic lily ‘Brunello’. This experiment was conducted randomized complete block design with 9 treatments and 3 replications. Treatments included drench of potassium silicate in three concentrations (25, 50 and 75 mg l-1), spray of potassium silicate in concentration of 25 mg l-1, spray of calcium chloride in two concentrations (25 and 50 mg l-1) and spray of nano-silicon in two concentrations (12.5 and 25 mg l-1) and control. Quantitative and qualitative characteristics and flower postharvest longevity were measured. Results showed significant differences between treatments. Calcium chloride compared to potassium silicate and nano-silicon, significantly increased fresh weight of flower stem at harvest time and drench of potassium silicate at 25 mg l-1 resulted in maximum number of florets 5.27). Maximum flower vase - life was related to spray of potassium silicate at 25 mg l-1. Spray of potassium silicate significantly increased flower vase - life than drench, for one extra day. The results showed that in general, the effect of potassium silicate was more effective than calcium chloride and nano-silicon on improving the measured characteristics particularly floret number and vase - life.

Due to complex identification of young date palm cultivars (Phoenix dactylifera L.) using morphological traits, advanced molecular tools have provided a new prospect for DNA fingerprinting. In this study, specific molecular keys were identified for 10 Iranian date palm cultivars using 16 SSR markers. The results showed that 7 SSR markers produced polymorphic for studied Iranian date palm cultivars. SSR markers MPA 4 in ‘Estameran’, MPA 6 and 10 IN ‘Piarom’, MPA 10 and 12 in ‘Shahani’ and ‘Piarom’ produced specificmolecular keys. Furthermore, combination marker MPA 6-12 in ‘Kabkab’, ‘Mazafati’ and ‘Shahani’, MPA 5-10 in ‘Berhi’ and ‘Shahani’, MPA 10-12-6 in ‘Gantar’ and MPA 16-6-12- 4-7-10 in ‘Deiri’ produced specific keys. The results showed that there was a different genetic background within ‘Deiri’, ‘Rabi’ and ‘Piarom’ mother’s trees. The specific molecular keys were verified on 50 date palm mother’s trees and the results were confirmed at two independent laboratories. The reported specific molecular keys can be used for identification of 10 Iranian date palm cultivars. In this study, we determined genetic diversity of dcommercial date palm cultivars, by using microsatellite markers. From the used 12 simple sequence repeat (SSR) markers, we detected a total of 19 alleles with an average of 3.57 alleles per locus and an average polymorphism information content of 0.39. In addition to diversity parameters, Bayesian assignment tests and phylogenetic network analysis were used to determine population structure. Thus, the present results indicated that the assessment of genetic diversity and population structure of the date palm germplasm would benefit to make use of these germplasm as well as applying them in association mapping.

Salinity is one of the most common environmental stresses which adversely affect crop growth and productivity. Salicylic acid and methyle jasmonate increase tolerance of plants to biotic and abiotic stresses. Therefore, the aim of this study was to examine the effects of exogenous salicylic acid and methyle jasmonate on vegetative growth of strawberry (Fragaria ananassa cv. ‘Camarosa’) under salinity stress conditions. In this regard, a factorial experiment, in a completely randomized design (CRD) with three replications was used to investigate the effects of three salinity levels (0, 30 and 60 mM NaCl) and various levels of salicylic acid (0, 0.1, 0.5 or 0.75 mM) and methyle jasmonate (0, 0.25, 0.5 or 0.75 mM). The results indicated that by increasing the levels of salinity stress, vegetative characters (petiole diameter, petiole length, leaf numbers, fresh and dry weight of shoot and roots), significantly decreased but application of exogenous salicylic acid and methyle jasmonate significantly improved the most vegetative characters above. Salt stress decreased the relative chlorophyll content. Salicylic acid (0.1 mM) and methyle jasmonate (0.75 mM) improved the relative chlorophyll content. Also by increasing the levels of salinity stress, Na/K ratio in roots and shoots were increased, salicylic acid and methyle jasmonate decreased this ratio in the shoots with no effect in the roots. Peroxidase activity was increased in salt stress conditions and 0.5 mM salicylic acid and 0.25 mM methyl jasmonate increased the activity of this enzyme. In brief, the salicylic acid and methyle jasmonate treatment reduced the damaging effects of salinity.