Journal of Horticultural Science
Year:2010 | Volume:24 | Issue: 1|Papers Count:20

Strawberry is one of the most important fruit crops in the world. In this study, effect of different plant densities were studied on yield and fruit quality of strawberry ‘Selva’ in greenhouse and laboratories of university college of agriculture and natural resources during 2002-2003. Uniform stolens of strawberry were planted in holes of plastic column according to Factorial in Completely Randomized Block Design with three replications. In each column, 16 or 24 stolens were planted and space among columns was 75 or 100 cm. according to statistical design. Results showed that number of plants in each column had significant effect on each plant yield. However, different space among columns had significant effect on each plant and each column yield in a way that yield was higher when 16 stolens were planted in each column and distance among columns was 100cm. In each column, stolens in top of plastic column had higher yield compared with those in bottom of plastic column (each plant at the top 50 cm. of plastic top had 50gr more yield which ended up to 300gr more yield for that part of column). In spite of higher yield for above-mentioned treatment, plant density of 24 plants per column and distance of 75cm. among columns produced more fruits per unit (m2) of greenhouse. The above-mentioned treatments had some effects on most qualitative characteristics of fruits such as length and diameter of fruits, vitamin C content, pH, TSS, TA, TSS/TA, which generally were higher for treatment of 16 plant/column and distance of 100cm. among columns. However, these differences did not reach significant level.

Paclobutrazol is one of the most important triazolic compounds which are used as growth retardants in some crops. In this study, the effect of application methods and concentration of Paclobutrazol on plant height of tuberose and possibility of pot production was investigated. In the first experiment, tuberose bulbs were soaked in 0, 25, 50, 75 and 100 mg.l-1 paclobutrazol for 10, 20 and 30 minutes and then planted in pot. The experiment was conducted using a factorial experiment in completely randomized block design with 4 replications. In the second experiment, plants (20 cm hight and fully expanded leaf) were sprayed with 0, 15, 30, 45, 60 and 75 mg.l-1 Paclobutrazol using completely randomized design with 5 replications. In each experiment, the control treatment consisted of untreated bulbs. Results indicated that the tallest plants (54.54 and 60.40 cm in soaking and spray experiment respectively) were control plants. The earliest flowering (107.3 days after planting) also was seen in control plants whereas flowering was delayed to 122.2 days using 100 mg.l-1 paclobutrazol. Shoot length, rachis length and floret number were affected by concentration of paclobutrazol using in preplant bulb soak and spray methods. Our results showed that paclobutrazol could control plant size in relation to pot size.

Many preharvest and postharvest factors and conditions influence the nutritional value and storage life of horticultural commodities. The present study, the response of tomato fruits produced from different growing media, tea waste, tea waste + zeolite (1:1), tea waste + zeolite (3:1), tea waste + zeolite (1:3), zeolite + perlite (1:2) (V/V) in soilless culture to two different storage temperature were investigated. The results showed that keeping quality of fruits such as antioxidant capacity and total phenolic compounds affected by storage temperature. The response to storage temperature was different among the fruits that produced on different growing media. Fruits weight loss was affected by storage temperature and growing media could not change it. The declining antioxidant capacity and phenolic losses were accelerated at higher temperatures (20oC) and longer storage durations. Fruits produced on tea waste have been showed the highest antioxidant capacity and phenolic compounds after two weeks storage.

Effects of three different level of SO2 generating pads with 1gr kg-1 concentration (one on top, half on top and half on bottom of the packaged grapes and without sulfur pad) Combined with two type of polyethylene bags (perforated and imperforated) during cold storage (135 day) on some traits of grape cv Qzl ouzum such as: weight loss (%), bleaching, fungal rot (%), rachis desiccation, berry shriving, pH, TSS, TA, taste and sulfite residue was studied. Result showed that SO2 generating pads treatment significantly decreased weight losses, rachis and berry shriving and decay rate. Whereas bleaching and off flavors of grapes were increased. Imperforated bag treatment significantly decreased weigh losses, bunch and berry shriving. Among all sulfur pads treatments, the highest and the lowest sulfur taste was measured in two sulfur pad treatment with imperforated bags and one sulfur pad with perforated bags, respectively. Results of sulfite residue measurement showed that the highest sulfite residue means were observed in one and two sulfur pad treatment with perforated bags, respectively, whereas in imperforated bags, sulfide residue was less than 10 ppm at both sulfur pad treatments.

To compare the effects of different drying temperatures and different microwave powers and two different natural methods (shaded and sunny area) in chamomile (Matricaria recutita (L.) Rauschert CV. Germania (diploid)) essential oil and chamazolene content, drying time and drying rate, an experiment was carried out at the research field of Ferdowsi University of Mashhad (FUM), Iran during 2007-2008. The experimental design was completely randomized block design including three temperatures: 50, 60 and 70oC, six microwave powers: 100, 180, 300, 450, 600 and 900 w and drying in shaded and sunny area, with three replications. The drying process was continued until the mass of the sample reduced to a moisture content of about 0.10 on a dry basis or 10% on a wet basis. The results indicate that different treatments of drying had a significant effect on the drying time, drying rate and essential oil and chamazolene content. The maximum essential oil content (%0.72) obtained at drying in shaded area and the lowest one was obtained at drying by microwave and high temperatures of oven. Maximum chamazolene content obtained at microwave drying (except 100w power) and natural method (both shaded and sunny areas). Minimum chamazolene content was obtained at drying by oven.

Biofertilizers are one of the main sources to supply nutrient elements for plants in sustainable agriculture. In order to evaluate the effects of biofertilizers and chemical fertilizers on Cumin (Cuminum cyminum) as a medicinal plant a field experiment was conducted in the Research Farm of Faculty of Agriculture, Ferdowsi University of Mashhad in a randomized complete block design with three replications in year 2008. The treatments were nitrogen fixation bacteria (Azotobacter and Azospirillium) and phosphate solublizing bacteria (Pseudomonas flurescence) in pure and combination treatments and chemical fertilizers treatment compared with control treatment. The result indicated that performed treatments could significantly enhance the yield and yield components. Biofertilizers increased the biological yield, seed yield, plant height, number of umbers per plant, number of seed per umber, number of seed per plant and the thousand seed weight. Combination use of Azotobacter and Azospirillium with pseudomonas had better effect on most of the studied characteristics compared with other treatments. In general, biofertilizers could be a good substitution for chemical fertilizers in cumin production.

Tuberose is one of the most important cut flowers in Iran and the world. In this experiment, effect of microelements Fe, Zn, Cu and Mn on inflorescence length, inflorescence bunch length, number and diameter of floret, diameter of inflorescence bunch and vase life of tuberose flowers were studied. This study was based on four separate completely randomized experimental design with four replicate and four concentrations include: 0, 2, 4 and 6 mg/lit for each microelement. The fertilizers were sprayed in three stages. The first stage was at eight leaf stage (after 30 days). The second stage was, one month later from first stage and the third stage was one month after second stage of plant growth. The results showed that the concentrations of 6 mg/lit of Fe SO4 on inflorescence length and floret number, 2 mg/lit on bunch length and 4 mg/lit on floret opening was significant (P³1%). The concentrations of 2 mg/lit of Cu SO4 on length of flower bunch and floret number, 6 mg/lit on floret opening percentage and inflorescence diameter and 4 mg/lit on length of inflorescence was effective. Almost all traits were affected by Mn SO4 with 6 mg/lit concentration and vase life reached to 12.4 days.

Lettuce is one of the best accumulators of heavy metals and nitrate between leafy vegetables. Through this research, it was tried to decreased cadmium absorption with humic acid (HA) and studies the effect of HA on the accumulation and metabolism of nitrate. Plants were grown in the peat/perlite and irrigated with Hoagland solution with addition of cadmium (2 and 4 mg L-1) and HA (100 and 1000 mg L-1). Results showed that Cd in media increased Cd of leaves and decreased protein and fresh weight but it has not any effect on the N, P and nitrate concentration and nitrate reductase activity. With increasing concentration of HA, increasing in fresh weight, N, protein concentration and decreasing in Cd concentration in leaves was observed. Using of HA and Cd together in nutrient solution showed that HA decreased absorption of Cd. So toxic effect of Cd decreased on the physiological changes of lettuce and do not accumulate nitrate in leaves, as well. More investigations should be done for using HA on the polluted soil for planting of lettuce.

In this study different proportions of NH4+ and NO3- in the growth medium on plant growth were investigated in hydroponic greenhouse experiments. The objectives of these studies were to investigate if ammonium (NH4+) stress in cucumber, a species sensitive to NH4+ toxicity, can be alleviated by matching the nitrogen supply rate to the plant nitrogen demand. Ammonium was applied at a relative addition rate of R=0.15 day-1 or R=0.25 day-1. For comparison, plants were also grown with NO3- as N source, as well as at constant concentrations of 1 and 4 mM NH4+. The fresh weight of plants grown with NH4+ as sole N source at R=0.15 day-1 was similar to that of NO3--fed plants, while at the high NH4+ supply rate of 0.25 day-1 a small growth reduction occurred. When available as a constant concentration, NH4+ decreased plant growth at 4 mM. Root: shoot ratio was lower in NH4+-fed plants compared to NO3--fed plants, and the NH4+-fed plants had more branched roots. Calcium concentration decreased in the roots, stems and leaves of NH4+-fed plants compared to NO3--fed plants. There were no differences in leaf chlorophyll fluorescence at the various N treatments. It is concluded that even a putative NH4+ sensitive species such as cucumber can tolerate NH4+ if the supply rate matches the N demand of the plants.

Persian walnut is one of the most important nut crops in Iran. Now the majority of orchards are seedling with a great diversity. For establishing uniform orchards and increasing the quantity and quality of yield, patch budding as the most suitable propagation methods, have still technical and practical problems in the country. In spite of high percent of primary success in patch budding but the final success is very low. In this study, the effects of Indole-3-butryic acid (IBA) and gibberellic acid (GA3) were evaluated on four cultivars and one genotype of walnut to increase bud growth and graft success. The results showed that there were significant differences among the different levels of both the hormone on increasing total success of budding, bud growth and decreasing dried and dormant buds. Mean comparisons showed that IBA 50 ppm with %56 in comparison with control with %26 had the highest effect on bud growth. Meanwhile the other hormone treatments increased the bud growth at least %20 comparing with control. Among the cultivars, the highest and lowest bud growth belonged to ‘Chandler’ (%58) and ‘Z63’ (26). The interaction between hormone treatments and cultivars on bud growth showed that ‘Chandler’ had the highest response to GA3 100ppm and IBA 50 ppm, ‘Pedro’ to IBA50, while for ‘Z63’ IBA 100 had the best effect. This study showed that suitable hormone treatment could overcome a part of problems relating to low level of graft success in walnut.

The harvesting time and storage conditions of olive fruit are effective factors on the quality and quantity of oil. The harvesting time of olive is different in each area and it depends on climatic conditions. This investigation was carried out to assess the impact of harvesting time on olive oil quality and quantity frome two olive varieties cultivated in Gorgan region. For this reason fruits of selected cultivars, Mishen and kroniki, were harvested with fifteen-day intervals from 6 September till middle December. Then quality and quantity of oil was determined. The results showed that dry matter, oil content (in dry), free fatty acids increased during ripening, whereas peroxide value decreased during ripening. Therefore, the best harvesting time for these cultivars is beginning of December.

In order to increase of quality and storage life of strawberry fruits (cv. ‘Selva’), UV-C irradiation at tow doses (5 and 15 min) and immersion in Methyl jasmonat solution with three concentrations (0, 1, 3 mMol/ lit ), were applied. A factorial experiment (Dummy Plot) was carried out with Randomized Completely Design at 8 replications. Fruits after harvesting, treated and stored in a cold storage in +2±2oC with 95% relative humidity for 14 days. Immediately after treatments and end of storage, quality traits including, total soluble solid (TSS), titrable acidity (TA), vitamin C, total phenols, decay percentage were measured. The results showed that fruits which took UV-C irradiation (5 min) and MJ solution (1 mMol/ lit), increased total phenol and decreased of decay percentage after 14 days of storage more than others. UV-C irradiation with Methyl jasmonat solution didn’t have any significant effects on TA, TSS and Vitamin C.

In this study, total phenolics content and antioxidant activity of peel and pulp and main phenolic compounds of fruit including chlorogenic acid, catechin, phloridzin, quercetin 3-galactoside, cyanidin 3-galactoside (Anthocyanin) and total flavonoids of peel of native cultivars ‘Ghandak’, ‘Heidarzade’ and imported cultivars ‘Golden Spur’, ‘Red Spur’ and ‘Red Delicious’ were quantified. Results showed that the selected cultivars have a significant variation regarding all factors except for cyaniding 3-galactoside. ‘Red Spur’, a red cultivar, had the highest catechin and phloridzin content. ‘Heidarzade’, a red cultivar, indicated the highest quercetin 3-galactoside and cyaniding 3-galactoside and total flavonoids. There was a positive relation between total phenol content and antioxidant activity. The peel of studied cultivars had higher content of total phenol and antioxidant activity compared with pulp. Among the experimental cultivars, the peel of ‘Red Spur’ and the pulp of ‘Heidarzade’ had the highest total phenol content and antioxidant activity.

Apricot fruit because of its high respiration rate and rapid ripening process has short storage period and should be offer to marketing immediately after harvest. This study was carried out to determine the optimum harvest time of apricot fruits to prolong their storage period and decrease its wastes. Split-split plot based on complete randomized block design were used for four traditional apricot cultivars include of “Germez shahroud”, “Gorban maragheh”, “Orduobad” and “Nasiri” (as main factor) in three harvesting stages (as sub-factor) based on fruit skin color. The first harvest was conducted when skin color had a predominantly green background with yellow tinges, the second and third harvest coincided with yellow background with green tinges and yellow-orange background color of fruits. Then fruits were packed in boxes with polyethylene covers and stored at 0-2oc and 85% RH. For 0, 7, 14, 21 and 28 days (as sub-sub-factor). After each storage period, fruits were tested for their quality attributes such as shriveling, gel breakdown and decay percentage. Other fruit properties included fruit weight, firmness, TSS, pH and EC were measured and data were analyzed. The cluster analysis results related to quality traits of fruits revealed four distinct classes. Results showed that optimum harvest time of all cultivars is when the fruit skin color has a predominantly yellow background with green tinges and prolong storage period. At these conditions, the fruits of “Germez shahroud”, “Gorban maragheh”, “Orduobad” and “Nasiri” could be cold-stored with suitable quality until 21, 28, 21 and 28 days, respectively.

Effect of different concentrations of salicylic acid on postharvest life of kiwifruit (Actinidia deliciosa) cultivar Hayward at 0±0.5oC and 90-95% RH was studied. Fruits were treated with salicylic acid (0, 1 and 2 mmol/L-1) and stored at 0±0.5oC for 16 weeks. Fruit quality attributes assessment including firmness, total acidity, soluble solid content, ascorbic acid, antioxidant activity, catalase enzyme activity and total protein content was conducted after 8 and 16 weeks of cold storage. Salicylic acid treatment significantly retained fruit firmness and 2 mmol/L-1 was the most effective treatment in retaining fruit firmness. salicylic acid treatment also had a significant effect on total acidity after 16 weeks and ascorbic acid after 8 weeks, but had no significant effect on soluble solid content. Salicylic acid significantly affected on antioxidant activity. Effect of salicylic acid had a significant increase in catalase enzyme activity and total protein content after 16 weeks of cold storage.

Essential oils (EOs) of Achillea eriophora, extracted by hydrodistillation and their constituents were analyzed by gas chromatograph (GC) and GC/mass spectrometry using retention indices and fragmentation patterns. The antibacterial effects of the EO was assessed on several food-borne pathogens, namely Staphylococcus aureus, Bacillus cereus, Escherichia coli O157:H7, Salmonella enteritidis, and Listeria monocytogenes using microdilution technique by ELISA reader device. Results showed that the essential oil content of the plant was more than other Achillea species. GC analysis of the EO confirm the presence of 36 constituents that the main condstituents were camphor (28.65%), 1, 8 cineol (26.95%), camphene (5.98%), b-Pinene (4.8%) a-pinene (4.2%) and borneol (4%). MIC of the EO agains gram positive baccteria ranged 0.15-0.75 mg/ml and against gram negative bacteria was 1.5-3 mg/ml. The most sensitive pathogene was S. aureus and the most tolerant one was S. enteritidis.