IRANIAN JOURNAL OF HORTICULTURAL SCIENCE AND TECHNOLOGY
Year:2006 | Volume:6 | Issue:4|Papers Count:9

Experiments were conducted to micropropagate pyrethrum using shoot–tip explants, cultured on Murashige and Skoog (MS), Gamborg (B5) and Schenk and Hildebrandt (SH) media. Axillary buds were excised from greenhouse-grown plants. After one month on MS medium, shoot explants were transferred to MS, B5 and SH media supplemented with different concentrations of benzyl adenine (BA) (0, 0.5, 1, 1.5, 2, 2.5 and 3 mg l-1), and naphthaleneacetic acid (NAA) (0, 1, 2, 4 and 6 mg l-1) After 6 weeks, proliferation rates of shoots were recorded. The highest proliferation rate was observed on MS medium supplemented with 1.5 mg l-1 BA and 2 mg l-1 NAA. The highest means of shoot length were observed on all the media without BA and using BA in culture media resulted in production of short shoots. The highest fresh weight of shoots was observed on MS medium compared to B5 and SH media. The interaction between growth regulator treatments in all the media supplemented with the highest concentration of BA and all NAA concentrations resulted in lowest fresh weight of shoots. All media supplemented with different concentrations of NAA were used for rooting of the shoots. The roots were observed in all the media after 4 weeks. NAA at the concentration of 2 mg l-1 produced the highest root number in all media. Also in all the media, the highest root length was produced in control treatment and increasing the NAA concentrations significantly decreased mean root length. The plantlets were successfully acclimatized in a 3:1 (v/v) vermiculite: peat mixture.

The experiment was conducted to studying the effects of planting dates and within-row spacing on onion ‘Yellow Sweet Spanish’ seed yield and quality at Kabootar Abad Research Station of Isfahan during 2002-2004 growing seasons. The experiment was conducted using a split-plot with a randomized complete block design with four replications. Main plots were three planting dates (23 rd Oct., 20th Feb. and 5th Mar.) and subplots were three intra-row spaces (15, 20 and 30 cm). Results showed that the first planting date had the highest seed yield (640 kg ha-1), number of umbels m-2 and capsules umbel-1 as compared with the second and the third planting dates. Seed yield and umbels m-2 was decreased significantly as plant space increased from 15 to 30 cm. The number of capsules umbel-1 increased in 15 cm plant space as compared to the other planting spaces. Planting dates and intra-row spacing did not have significant effects on the number of seeds capsule-1 and 1000 seeds weight. Among yield components, umbels m-2 and capsules umbel-1 had the most contribution in the seed yield variation. Seed germination percentage and rate, in the first planting date were higher than the other planting dates, but plant spacing had no effects on the seed quality traits.

Date palm (Phoenix dactylifera) is one of the important and strategic agricultural crops. Based on FAO report in 2002, the area under cultivation of date palm is estimated 1100000 ha with total yield of 6135000 tons per year. Date palm is cultivated in all continent of the world but 99 percent of total yield is from Asia and Africa continent. More than 85% of total yield belongs to 5 countries namely Egypt, Iran, Iraq, Saudia Arabia and Pakistan. The amount of fertilizers supplied to the plants will affect the concentration of elements in plant parts. Concentration of each essential element in different plant parts varies in different physiological stages and plant tissues. Previous investigations showed fluctuation of nutrients status in different crops, but there is no report on date palm. Therefore, an experiment was conducted with the aim of determining the fluctuations in essential elements status in different leaves of date palm. Three date palm tree (cv. ‘Sayer’) leaves, according to Nested design were numbered from top leaf watch handle moving direction at reproductive stage. The leaflets from middle of each rachis were sampled and concentrations of essential elements were determined. The fluctuations in essential elements, such as N, P, K, Ca, Mg, Fe, Zn, Cu and Mn status were determined in different leaves of date palm. Results showed that the concentration of N increased from the first row of leave through the 7th row and then decreased through the 10th row. The concentration of P, K and Cu decreased, whilst Ca, Mg, Fe, Zn and Mn increased with increasing leaf age.

Gerbera is amongst the ten major cut–flowers in the word. At present, the plantlets of this commercial plant are imported to Iran from the Netherlands. For micropropagating the gerbera, thidiazuron (TDZ) as a growth regulator was used at 0.01, 0.1, 0.5 and 1 mg l-1 for shoot production from young capitulum explants. The capitulum of ‘Mammut’ and ‘Jaimy’ at less than 10 mm diameter were cultured on MS media supplemented with different concentrations of TDZ. The cultures were kept in darkness at 21±2 ºC temperature for one month. Then the cultures were incubated in 2500 lux and 16 h illumination at 25±2 ºC. The highest number of shoots was obtained from 0.5 and 0.1 mg l-1 TDZ with average of 4.5 shoots per explants. The highest number of shoot was obtained from ‘Jaimy’ with mean 3.7 shoots per explants. The longest shoots were obtained on medium supplemented with 1 mg l-1 TDZ in average 2.6 cm and the lowest were produced on medium with 0.01 mg l-1 TDZ with an average of 0.85 cm) of shoot proliferation was evaluated on MS media with different  concentrations of kinetin: 1, 2, 4 and 6 mg l-1. The highest number of shoots was produced on medium containing 6 mg l-1 kinetin with an average of 4.6 shoots. Cut shoots were rooted on MS medium without any growth regulator. The experiments were conducted as a completely randomized factorial design with three replications.

The use of hyacinth flowers has attracted attention due to the variability of their colors and scent. Hyacinth is a bulbous flower, which usually propagates through bulbs and bulblets. Due to high cost of hyacinth bulb importation, and the limitation of bulb production in field and greenhouse cultures an investigation was carried out to propagate hyacinth bulb through tissue culture through direct organogenesis using scale, leaf primordia and immature floret as explants. A factorial experiment in a completely randomized design with 3 replications was carried out. Explants were cultured in four direct organogenesis media including: 1-    Basal MS medium supplemented with 1 mg l-1 BAP and 0.1 mg l-1 NAA 2-    Basal MS medium supplemented with 3 mg l-1 BAP and 0.3 mg l-1 NAA 3-    Basal MS medium supplemented with 1 mg l-1 BAP and 0.1 mg l-1 IBA 4-    Basal MS medium supplemented with 3 mg l-1 BAP and 0.3 mg l-1 IBA  The best leaf primordial with a mean number of 5.9 bulbs obtained on basal MS medium supplemented with 1 mg l-1 BAP and 0.1 mg l-1 IBA after 6 weeks. After 12 weeks, scale explants cultured on basal .ation,and the level MSmedium supplemented with 3 mg l-1 BAP and 0.3 mg l-1 IBA showed an increase in bulb formation, 1.5 times of bulbs produced after6 weeks. Three basal MS media supplemented with 0, 0.5 and 1 mg l-1 NAA were used for rooting the bulbs from which 0.5 mg l-1 NAA showed a 90 % rooting.

Recommendation of a perfect rootstock with superior traits for different commercial cultivars of Citrus is impassible. Selecting the rootstock should be based on production goals and the planting region. The experiment was conducted to evaluate three rootstocks on ‘Thompson Navel’ tree growth, yield, fruit size, TSS, TA, vitamin C and TSS/TA. The experiment was carried out as a randomized complete block design with four replications in Astara Research Station. The evaluated rootstocks were: poncirus [Poncirus trifoliata (L.) Raf], citromelo [(Poncirus trifoliata (L.) Raf) × C. paradisi)] and Troyer citrange [Poncirus trifoliata (L.) Raf × C. sinensis (L.) Osbeck.]. Rootstocks affected fruit size, TSS, TA, vitamin C and TSS/TA, but the differences were not large enough to affect the market values of the fruits. Results indicated that poncirus and citromelo rootstocks produced higher yield than citrange and poncirus rootstock had the highest yield efficiency. Fruits on poncirus and citrange rootstocks had more TSS and TSS/TA. Evaluation of quantity and quality characteristics indicated that poncirus and citromelo rootstocks were the best.