مجله علوم باغبانی ایران
سال چهلم شماره 2 (تابستان 1388)

Limited ovule longevity is a major obstacle to fruit set and productivity in most fruit trees including almond. Therefore, a study of Effective Pollination Period (EPP) in fruit trees is of special importance. The present research was carried out to determine EPP in the almond cv. 'Shahrood 12' during 2005 growing season. Flowers of "Shahrood 12" (?) as a mother plant were pollinated with the pollen of "Supernova" (?) and "15-5" (?) cultivars 1, 2, 3, 4, 5, 6 and 7 days after anthesis. Pollinated flowers were sampled for microscopic examinations of the pollen tube growth in the style after 24, 48, 72, 96 and 120 hours past from pollination. The samples were fixed in FAA solution, stained with aniline blue and prepared for being observed for pollen tube growth under florescence microscope equipped with UV light. In addition, fruit number set was recorded on the 75th Days After Full Bloom (DAFB). Results indicated 34 and 37% fruit set when "Shahrood 12" (?) pollinated with "Supernova" (?) cultivar on days 2 and 4 after anthesis respectively. Also, fruit sets of 37 and 42% were observed when "Shahrood 12" (?) was pollinated with "15-5" (?) cultivar on 2 and 4 days after anthesis, respectively. In addition, results as based on the microscopic examinations of the pollen tube growth in the style showed the low fruit set from those flowers pollinated 7 days after anthesis which was due to the less longevity of ovules and stigma. In conclusion, results as based on the field and microscopic examinations showed the better results for fruit set when flowers of "Shahrood 12" (?) pollinated with pollen of "Supernova" (?) and "15-5" (?) cultivars on the 2nd and 4th days after anthesis. Any later pollination of the mother plant is not suggested because of low fruit set leading to reduction of yield. Pollination at 2-4 days after anthesis is suggested to maximize fruit set and to further crop production throught lengthening the overlap duration of the flowering periods of compatible pollinizers with "Shahrood 12" under Karaj environmental conditions.

To evaluate growth characteristics and adaptation of new Asian pear cultivars (Pyrus serotina Rehd.) in Iran, some growth characteristics and physiological factors of nine Asian pear cultivars named ‘KS’6, ‘KS’7, ‘KS’8, ‘KS’9, ‘KS’10, ‘KS’11, ‘KS’12, ‘KS’13, ‘KS’14 and one European, present commercial cultivar ‘Shahmiveh’ of Iran (control) were evaluated under the climatic conditions of Tehran Province. The experiment was carried out employing nine Asian pear cultivars grafted on European pear (Pyrus communis L.) seedling rootstocks. Some growth characteristics and physiological factors of budded plants were assessed during two growing seasons. The results showed that more than 80% of grafting was a success in the first season and survival of budded trees amounted to 100% towards the end of the second growing season. Budded cultivars showed different growth responses in terms of shoot growth, Trunck Cross Sectional Area (TCSA), leaf number and area in the first and second seasons growth. ‘Shahmiveh’ (control), ‘KS’7 and ‘KS’11 cultivars had the highest shoot length, leaf number, TCSA and leaf area in the first season. ‘Shahmiveh’ showed a higher Absolute Growth Rate (AGR) by the end of the first season's growth. Although, the differences between Asian pear cultivars in terms of AGR were not significant but these cultivars showed a higher AGR than ‘Shahmiveh’ cultivar during the second season's growth. The differences on such leaf mineral concentrations as N, P, K, Ca, Mg, Mn and Zn among studied cultivars were significant. The highest N, P, and K was observed in ‘KS’9, ‘KS’12 and ‘KS’6 cultivars respectively, while the lowest concentration was respectively shown in ‘Shahmiveh’, and ‘KS’7. The lowest Ca, Mg and the highest Mn were observed in ‘Shahmiveh’ cultivar. In total, Asian pear cultivars showed a good growth performance on European pear seedling rootstocks under Tehran Province, environmental conditions. They, after being established, demonstrated a good growth characteristics and efficient nutrient absorption.

To study the effects of nitrogen on tomato plant growth and the possibility of reducing nitrogen in drainage water, two nutrient solutions (complete nutrient solution (N+) and nutrient solution with a 30% decrease in N concentration (N-)) along with and three culture media (perlite, a mixture of perlite and NH4- enriched zeolite and finally a mixture of perlite and raw zeolite) were employed for growing greenhouse tomato plant (cv. Breil). The experimental designe was a split plot one with a complete randomized design of 3 replicates. Results indicated that LAR and LER decreased with reducing nitrogen. Zeolitic media improved such growth factors as stem length, leaf number, SER, CGR and increased yield, while use of enriched zeolit decreased nitrogen in wastewater. The least SLW and highest SLA were obtained throught an interaction effect of complete nutrient solution and enriched zeolite bed. Concentration of nitrogen in young leaves decreased with reducing nitrogen in solution but this didnt happen in NH4-enriched zeolite media.

Tolerance of two apple rootstocks (Gami and M26) was evaluated at different concentrations of sodium chloride in vitro conditions. Micro plants grown under MS medium culture were transferred to Knoudson–C culture medium devoid of Na and Cl ions. Concentrations of NaCl in the knoudson-C culture medium were 0, 20, 40, 60, 80 and 100 mM/l. Six weeks after culturing, data were collected. The results indicated that the effects of rootstock, salt concenteration and interaction of rootstock and salinity on evaluated characteristics were significant, but the interaction of rootstock and salinity exerted no significant effect on dry weight of roots. As the NaCl concentration in the culture medium increased, the length of shoots and roots, fresh and dry weight of shoots and roots, number of roots and leaves significantly decreased, but the percentage of yellowing of leaves and sodium uptake, as well as proline and soluble sugar contents increased. According to the results, means of shoot and root length, fresh and dry weight of shoot and root, number of leaves and roots, proline and soluble sugar contents were higher in Gami apple rootstock than in M26, but percentage of dried leaves and sodium uptake were lower in Gami rootstock than in M26. According to the obtained results Gami was more resistant than M26 rootstock to salt stress under in vitro conditions.

This study was conducted to evaluate the responses of two greenhouse tomato cultivars to nutrient solution's electrical conductivity (EC). Two cluster type greenhouse tomato cultivars (Razan and Ergon) were grown in perlite in a glasshouse hydroponic system. The grown plants were daily fed with either constant EC nutrient solutions (ECs 2, 3 ds m-1) or nutrient solutions of alternatively changing ECs of 1.5, 2, and 3 ds m-1. The basis for EC change in the alternatively changing ECs treatment was the rate of evaportanspiration rate during the day. The results indicated that variable EC treatment could improve total soluble solids (TSS) in tomato fruit while the other quality factors (firmness, pH, titratable acidity and ascorbic acid) were not affected by nutrient solutions. The yield in variable EC treatment being equal to that in commonly used solution (EC=3 ds m-1) improved the economic profitability of mineral usage in hydroponics greenhouse tomatoe production systems. There were differences obsereved between the two cultivars in yield and quality characteristics. Ergon yielded higher, while Razan carried a higher TSS content.

To study yield and its components by the method of Multivariate Analysis, 25 genotypes of melon were sown on the basis of square lattice design of 2 replications in Zahak Agricultural Research Station. Analysis of variance showed that there were significant differences among genotypes in some such characters as: fruit weight, width, and seed weight and yield. Simple correlation coefficients showed positive and significant relationships between yield, and fruit weight, flesh diameter, seed weight, cavity diameter, fruit length and width. Factor analysis showed 3 factors describing near 77% of diversity among characters. Cluster analysis by method of least squares divided the genotypes into two groups. Analysis of variance for characters (in cluster analysis) showed a 1% difference of significance, indicating the accuracy of the cluster analysis.

A set of 29 persimmon genotypes were characterized using morphological characters and RAPD markers. Some fruit traits of: fresh weight, fruit length and diameter, firmness, fruit juice pH, TA, TSS, flavor index, fruit skin and flesh color, seededness, leaf length and width were evaluated. Analysis of variance for the investigated characters showed that genotypes were significantly different. Results of simple correlation analysis indicated the existence of significant positive and negative correlations among some characters. Factor analysis was employed for a determination of the number of main factors. The effective factors were categorized in four groups that totally expressed 76.75% of total variance. In RAPD analysis, totally 100 primers were used, among which 13 showed good amplification and polymorphism. These primers produced 65 bands, among which 64 were polymorphic. Cluster analysis was performed using Jaccard’s similarity coefficient matrix and UPGMA method. At similarity distance of 60% on the dendrogram, the genotypes were divided into 4 sub-clusters. Wild genotypes separated from kaki genotypes and produced two groups of lotus and virginiana species. Kaki genotypes also divided into two groups of common type and Japanease types. Cophenetic coefficient between similarity matrix and the dendrogram (r=0.97) showed the goodness of fit for the dendrogram and the similarity data

1-MCP, as an ethylene action inhibitor, significantly delayed the wilting of cut carnation.This study was carried out to determine the optimum concentration and duration of 1-MCP application on vaselife of cut carnation c.v 'Tempo'. Six levels of 1-MCP concentrations (0,20,40, 60, 80 and 100 nl.1-1) as well as three application times (3, 6 and 9 hours) were studied in a factorial compeletly random design of 3 replications to see the effect on vaselife, ethylene production, dry weight as well as flower opening index. Three hundred and twenty four cut carnations were kept in a postharvest room of: 20?2?C temperature, 60-70% relative humidity, 15-20? mol S-1 m-2 light intensity, and 12 hours of photoperiodism. Results indicated that the differences among treatments were significant only for concentration treatment on raselife longevity. As regards vaselife, ethylene production and flower opening index (P?1%), and dry weight (P?5%) were significant. The treatment of 60 nl.1-1 of 1-MCP with 15.49 days of vaselife, 0.34 nl.1-1h-1gr-1 of ethylene production and 19.75% dryweight, was the better treatment as compared with control plants.

Three separate experiments were conducted to investigate micropropagation of four pear cultivars. In the first trial, the effect of four cultural media (MS, MS/2, MSN/2 and MQL) were compared on such traits as shoot length, shoot number and color of leaf. From among the media, MS/2 and MSN/2 resulted in the most shoot proliferation and the longest shoots respectively. MS medium produced green developed leaves as compared to MSN/2, and MQL medium resulted in severe chlorosis accompanied by decrease in shoot growth. For a more precise evaluation of media (the second trial), 10 namely including the previous ones plus their modified versions were tested while the leaf size being measured too. Based upon the results of the first and second trials, MS/2 was the best medium among all. A third trial was conducted to determine the effect of BA concentration and auxin types on shoot proliferation of the evaluated cultivars in MS/2 medium. ‘Shahmiveh’ and ‘Dargazi’ produced the highest shoot numbers in 2 mg/l of BA concentration while, ‘Williams’ and ‘Natanzi’ produced the same in 3 mg/l of BA concentration. Equal concentrations of IBA and NAA (0.1 mg/l) in combination with BA showed that IBA led to the production of longer shoots than NAA.