گیاهان زینتی
سال:1393 | دوره: | شماره: |تعداد مقالات:7

The present study describes the encapsulation of protocorm of Cymbidium bicolor Lindl. from 60 days-old in seed cultures for shortterm conservation and propagation. Various concentrations and combinations of gelling matrix (sodium alginate) and complexing agents (calcium chloride) were tested to prepare uniform beads. The ideal beads were obtained through a combination of 3% sodium alginate and 100 mM calcium chloride. Encapsulated protocorms exhibited the best re-growth and conversion frequency on MS medium supplemented with BA (4.42 mM). Encapsulated protocorms stored at 25°C were green and retained the viability with potential for conversion (52%) and germination even after 360 days. The encapsulated protocorms stored at 4oC remained viable up to 30 days beyond which the conversion rate decreased drastically. Well-developed plantlets were transplanted into plastic pots containing vermiculite and maintained for 60 days in the culture room for acclimatization. The 90% of the recovered plantlets were hardened off and established successfully in the soil. The present study could be useful for large scale propagation as well as short term storage of this commercial orchid.

To Select an appropriate medium for the growth of plant is one of the problems of most greenhouse owners in production of pot ornamentals. So, current research was conducted to evaluate effect of some available media in mixtured by perlite on the growth of pothos. Study was based on a completely randomized design with 5 treatments, 8 measuring times and 6 replications in a fiberglass greenhouse of Gorgan University of Agricultural Sciences and Natural Resources during 2009-2010. The treatments include ratios of perlite+leaf compost, perlite+rice husk, perlite+cocopeat, perlite+composted forest trees and perlite+mushroom compost. Parameters such as plant height, stem diameter, leaf number, leaf fresh and dry weight and chlorophyll content were measured. Moreover, plants were compared according to their overall shape and appearance. The results of data analysis showed that the effect of medium, measuring time and their interaction were significant in all traits. The marketing value of pothos including plant height, leaf number and chlorophyll content, had a better response in perlite+leaf compost and perlite+mushroom compost media.

A research trial was conducted during 2011-2012 to elucidate the effects of humic acid (HA) and NPK to determine the optimum rate against different growth and floral attributes on tulip cultivar viz. ‘Triumph’. The following five treatments T0: (control), T1: 10 g/m2 NPK (17: 17: 17), T2: HA 0.75 ml (8%) +10 g/m2 NPK (17: 17: 17), T3: HA 1.00 ml (8%) +10 g/m2 NPK (17: 17: 17) and T4: HA 1.25 ml (8%) +10 g/m2 NPK (17: 17: 17) were applied under RCBD replicated thrice. All the vegetative and reproductive attributes were significantly influenced by the addition of humic acid and NPK and obtained results revealed that treatment T4 was the most effective one compared with the other treatments. This treatment gave the inimitable outcomes concerning earliest sprouting and flowering, plant height increment, leaf area expansion, stem diameter, leaf chlorophyll contents, stalk length, vase life, fresh and dry flower biomass. It also increased the nutrient contents comparing with the T3 and T2. In comparison, the plants grown without HA and NPK application (control) followed by a single application of NPK (T1) exhibited poor growth with reduced yield of inferior quality.The data obtained in this study conveyed that HA (1.25 ml of 8% humic acid) along with NPK application (10 g/m2 NPK) helps to improve the uniform crop stand, plant growth and flower quality of tulip.

In order to investigate the morphological reactions of cutting of damask rose to IBA (indole butyric acid) in different times, an experiment was done in a factorial experiment based on RCD and three times with three replications and 10 observations per each replication. In this experiment, the simple effects of IBA, time and their interaction effects were measured against morphological properties of damask rose rooting. Important measured factors were the root length, the percentage of rooting, the percentage of callus and the dry root weight. After immersing the cutting in IBA quickly for 5 seconds, the cutting were placed in the medium in a research greenhouse under mist system. According to the findings of the present research, in the simple effect of IBA, their time and interaction, the maximum increase in the average root length was obtained in 4000 mg/L-1 IBA and in cutting taken in winter. Similarly, the maximum rooting percentage was achieved in cutting treated with 2000 and 4000 mg/L IBA in March. The highest root dry weight was gained in March and in a concentration of 4000 mg/L of IBA.

The postharvest life of cut Eustoma grandiflorum flowers is limited in open flowers. Therefore a factorial experiment based on a completely randomized design with ascorbic acid (AsA) at 4 levels (0, 100, 200, 300 mg L-1) and citric acid (CA) at 3 levels (0, 100, 200 mg L-1) with 3 replications and 3 samples for each replications, was conducted for this purpose. Results indicated that a significant increase with applying ascorbic and citric acid nearly in all traits both individually and in combination, with higher concentrations imposing greater effects (p£0.05 and p£0.01). The highest vase life (17.6 days) and petal water content (68.9%) was observed for the interaction of ascorbic acid (300 mg L-1) and citric acid (100 mg L-1) and ascorbic acid (300 mg L-1) and citric acid (200 mg L-1), respectively, which shows a 94 and 252% increase compared to control (9.1 days and 27.3%). Along with this, relative water content and petal water content raised with AsA and CA increase. Water content also showed a similar manner. Fresh weight decreased in all treatments during experiment, but this reduction was much less in AsA (300 mg L-1) alone and in interactions with CA levels. According to the results of this experiment, ascorbic acid and/or citric acid as cheap, safe and biodegradable compounds are suitable alternatives for chemical treatments in order to prolong vase life of cut flowers of Eustoma. Commercialization of these compounds for optimum formulations needs further experiments.

Low seed yield is a limiting factor for cross breeding and hybrid seed production in cyclamen. This study was performed to investigate pollen germination and its relation to cross-pollination success and fruit set in this plant. In order to achieve a high level of pollen germination, the effect of different concentrations of chemical compounds were examined on in vitro pollen germination of cyclamen in modified Brewbaker and Kwack medium, containing sucrose (10 and 20%), calcium nitrate (0, 200 and 300 mg l-1), and boric acid (0, 100 and 200mg l-1) at two pH levels (5.5 and 6.5). Maximum pollen germination was obtained in media containing higher concentration of calcium and boron regardless of sucrose concentration and pH level. Pollen germination percentage was genotype-dependent. Cross-pollination was performed among four different genotypes characterized by various pollen germination percentages. There was a direct correlation between cross-pollination success and pollen germination percentage. Genotypes with 30% higher pollen germination led to 10% increase in fruit set.