سعدالله علیزاده

 To evaluate the effect of different levels of IBA (0, 1000, 1500 and 2000 mg/L) and position of take cuttings (lower, middle and upper) on rooting of greenhouse rose cultivar cherry brandy. In general, the aim of the research is to determine the best level of IBA hormone for the rooting of greenhouse rose cuttings, the possible effect of the possible of the cutting on the rooting rate of the cuttings, to determine the most suitable level of the hormone and the location of the cutting to produce the desired aerial part of the resulting cutting, In addition, to evaluate the best level of the hormone determining the most suitable position for cutting is based on some physiological parameters such as the relative content of leaf water and the efficiency of maximum chlorophyll fluorescence.

To conduct the experiment, the mother plants were purchased from a commercial greenhouse in Bostan-Abad and transferred to the physiology laboratory. To conduct the experiment, rose cuttings with a length of 10 to 12 cm and a diameter of 2 to 3 mm were prepared, and after removing the lower leaves, at least two end leaves were left on the cutting. In this research, a factorial trial based on a randomized complete block design with three replications was used. The traits measured in this experiment were rooting percentage, root fresh weight, number of roots, root length, relative leaf water content and variable to maximum fluorescence ratio.

 The results of the average data comparison showed that the highest rooting percentage of cuttings and root fresh weight were seen in the treatment of 1500 mg/L of IBA and in the cuttings of the lower and upper parts, respectively. The lowest rooting percentage of cuttings and root fresh weight were also observed in the cuttings taken from the upper of the branch without hormone application. The cuttings taken from the lower part of the branches at a concentration of 1500 mg/L of IBA had the highest number of roots, which did not show a significant difference with the middle cuttings of the branch at a concentration of 1500 mg/L and lower cuttings at a concentration of 2000 mg/L. The cuttings in the middle part produced the lowest number of roots in the control treatment. The cuttings taken from the middle and upper of the branch had the longest and shortest root length, respectively. The cuttings taken from the lower part of the branch at a concentration of 1500 mg/L and the middle part at a concentration of 2000 mg/L of hormone had the highest and lowest relative content of leaf water, respectively. The maximum variable chlorophyll fluorescence was observed in the cuttings taken from the lower part of the branch and treated with 1500 mg/L of hormone. The terminal cuttings also had the lowest variable chlorophyll fluorescence to the maximum under the absence of hormone application.

 Finally, due to the fact that the concentration of 1500 mg/L and the lower cuttings had the highest percentage of rooting, root length, root fresh weight, relative leaf water content and maximum variable chlorophyll fluorescence. It should be the best type of cuttings and hormone concentration for the rooting of rose cuttings. At the highest concentration of indole butyric acid (2000 mg/L) in most cases, there was a significant difference in the rooting characteristics of rose cuttings compared to the concentration of 1500 mg/L.
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Effects of different concentrations of IAA (0, 0.3, 0.6 mg/l) and 2ip (0, 0.3, 0.6, 0.9, 1.2 mg/l) and their combinations on callus induction and shoot regeneration of hypocotyl and its thin cell layer (TCL) explants in tomato was studied. Explants were prepared from hypocotyls of seedlings in the aseptic condition. Hypocotyl segments were more efficient than TCL explants for callus induction and it was occurred on the 96.0 percent of hypocotyl explants as compared to 76.5 percent of TCL explants. The mean diameter of formed calli on the hypocotyl explants were significantly more than TCL explants. The calli on hypocotyl explants were more regenerative than calli produced on TCL explants and 60.1 percent of calli produced on hypocotyl explants developed the shoots while the regenerated shoots from the calli of TCL explants were 21.45 percent. Percentage of shoot induction on TCL explants was maximum (47.44 percent) in the medium containing 0.3 mg/l 2ip and 0.6 mg/l of IAA. Explant typehad significant influence on the shoot number per callus. Calli developed on TCL explants regenerated more shoots significantly than hypocotyl explants. The recorded shoot number per callus of TCL and hypocotyl explants were 6.45 and 3.22, respectively. The mean length of developed shoots on the hypocotyl segments was significantly higher than that of TCL explants and maximum length of shoot was obtained on the medium containing only 0.3 mg/l IAA.

An experiment was conducted to investigate the effects of K/Ca ratios of nutrient solution on physiological traits, cut flower vase life and postharvest changes of rose. The main experiment was factorial based on completely randomized design with two cvs. of rose (Magic Red and Capitol), five K/Ca ratios in the nutrient solution (4:4, 6:4, 6:3, 8:3, 10:2) and three replications. Increasing the K/Ca ratio in the solution led to accumulation of K in the leaves but decreased the Ca concentration of the leaves. Furthermore, K/Ca ratio of the leaves was affected by K/Ca ratio of the nutrient solution and highest ratio of K/Ca was recorded for the leaves of plants fed with nutrient solution of 10:2 K/Ca ratio and the lowest K/Ca ratio of leaves was observed for plants which supplied with the nutrient solutions of 4:4 and 6:4 K/Ca ratios. The highest chlorophyll index was recorded for Capitol cv. and K/Ca ratios of nutrient solution had significant different effects on chlorophyll fluorescence. It was noted that rising K/Ca ratio caused lower longevity of cut flowers in both cvs. The highest necrosis of petals was occurred at 10:2 ratio of K/Ca and Magic Red cv. was more sensitive with the highest percentage of necrosis. The appropriate K/Ca ratio was obtained in the 6:4 ratio in terms of nutritional balance, reduced antagonistic effects of K and Ca, postharvest quality and more longevity of cut flowers.