مجله گل و گیاهان زینتی
سال پنجم شماره 1 (بهار و تابستان 1399)

Developing a highly efficient protocol for plant regeneration is a prerequisite for successful gene transformation in plants. To gain these properties, several experiments were conducted on various explants to optimize the concentration of plant growth regulators in regeneration of Gerbera. In the first experiment, regeneration of Gerbera plant was investigated using different explants including intact leaf, petiole, scratched petiole and Thin Cell Layer (TCL). Moreover, combination of BAP (0, 1, 2 and 3 mg L-1), TDZ (0, 0.1, 0.5, 0.8 and 1 mg L-1) and IAA (0.1 mg L-1) under 16/8 h light/darkness condition or one-month darkness were considered. In the second experiment, the regeneration potential of the first, second and third disc of TCL cut off from the end of the detached petioles were evaluated. Effect of different combination of BAP (0, 1 and 2 mg L-1), TDZ (0 and 0.5 mg L-1) and IAA (0, 0.1 and 0.3 mg L-1) on regeneration was studied. In all experiments, the MS-basal medium was used. The results showed that the best regeneration medium for intact leaf (33.2% regeneration, 66.3 shoots), petiole (86.66% regeneration, 33.33 shoots) and scratched petiole (53.2% regeneration, 33.10 shoots) was MS medium containing 2 mg L-1 BAP under 16/8 h light/darkness condition, and for TCL explants (46% regeneration, 29 shoots), 2 mg L-1 BAP with 0.5 mg L-1 TDZ in the darkness. In the second experiment, the highest rate of regeneration was obtained from the first disc of TCL explants on the MS medium containing 2 mg L-1 BAP, 0.5 mg L-1 TDZ and 0.1 mg L-1 IAA.

Calla lily (Zantedeschia spp.) is one of the monocotyledonous ornamental plants that is famous as pot plant and cut flower in the world. In the present study, in order to investigate indirect regeneration, different explants of calla lily cv. Orania were used in a Completely Randomized Design (CRD). In order to produce callus, explants of tuber buds, meristem, shoot-tip from tissue cultured plantlets and thin cell layer of stem were cultured on MS medium with different concentrations of BAP and NAA as treatment combination. Afterwards, the effect of using amino acid L-glutamine and adenine sulfate on increasing the shoot induction percentage was investigated. The highest percentage of callus formation (73.3%) was obtained from meristem explant on the MS medium containing 1 mg L-1 BAP along with 1.5 mg L-1 NAA. Due to the good quality of calli induced from the meristem explants, this explant was transferred to MS medium containing BAP, adenine sulfate and L-glutamine for regeneration. Highest regeneration percentage (78.3%), highest average number of shoots (13.4) and average shoot length (51.6 mm) were obtained on the media containing 1 mg L-1 BAP with 20 mg L-1 adenine sulfate and 300 mg L-1 L-Glutamine. Considering that calla lily is a recalcitrant plant in tissue culture, adding 500 mg L-1 activated charcoal to the rooting medium containing 0.25 and 0.5 mg L-1 IAA increased both rooting percentage and number of roots per plantlet. Furthermore, using amino acid L-glutamine (300 mg L-1) and adenine sulfate (20 mg L-1) increased the quality and number of plantlets produced from regeneration. Regenerated plantlets with proper length were transferred to the MS medium containing 0.5 mg L-1 IAA with 500 mg L-1 activated charcoal as rooting medium with the highest percentage of root induction (88.3%). Rooted plants were adapted (more than 70%) successfully in the perlite and cocopeat mixture (1:1) under greenhouse condition.

Orchis muscula L. is one of the worthwhile ornamental, medicinal, native and endangered species in Iran. In this research, plant tissue culture method has been used to propagate this valuable plant. For in vitro organogenesis, protocorm explants were surface sterilized and then cultured on different shoot and root induction media based on OrchiMax (OM) medium, supplemented with plant growth regulators with different concentrations alone or in combination. Based on results, the most shoot induction (100%) was obtained from protocorm explants cultured on medium containing 2 mg L-1 BAP and 0.5 mg L-1 NAA and the highest root induction (80%) was belonged to the treatment of IAA at 1 mgL-1.

Rosa iberica Stev. is one of the 14 wild rose species native to Iran. This plant has fragrant flowers and leaves. Therefore, one of the most important objectives of this study was to investigate the of crossability of R. iberica with R. damascena and commercial cultivars of Dolce Vita, Avalanch and Red One, as well as embryonic germination and some morphological characteristics of their offspring. This study was conducted to investigate the possibility of crossbreeding of R. iberica with R. damascena and 3 commercial cultivars of Rose Avalanch, Red One and Dolce Vita in a completely randomized block design for hybridization and a completely randomized design for embryo rescue in 5 repeat performed. The results of this study showed that the highest percentage of hip formation and the highest average number of seeds per hip from the intersection of R. iberica with R. damascena was 34% and 13.40%, respectively. Also, R. iberica as a pollinating parent was different from R. damascena seed parent and produced few hip and seeds. The results of crosses showed that the highest height, average number of leaves and green leaf percentage and chlorophyll content were belonged to id5 genotype. The only cross between R. iberica as the pollinating parent and the Red One cultivar as the parent was not successful, and the hips dried up and fell off the plant a few days after the crossing. In the crossings of R. iberica with Avalanch cultivar and also R. iberica with Dolce Vita cultivar, the average number of seeds per hip was 10.20% and 6.80%, respectively, and in the crossings between R. iberica as the pollinating parent with Avalanch cultivar as mother parent and also R. iberica as pollinator parent with Dolce Vita cultivar as mother parent, a large number of seedlings produced in the early stages of growth on MS culture medium were died, and in crossing of R. iberica with Avalanch and Dolce Vita resulted in the highest number of offspring. It can be attributed to gametophytic incompatibility, meiotic abnormalities and accumulation of recessive genes or differences in the ploidy levels of the resulting offspring. Findings of this study showed that R. iberica with production of the highest number of hips and high average seed production is very suitable for selection as a parent and also the resulting genotype is superior to the parent in most parameters studied, which can be used in upcoming breeding program for the traits of flowers, the aroma of flowers and leaves.

Calendula officinalis L. belongs to Asteraceae and is an ornamental and medicinal plant. Since diagnosis of medicinal plants growth under different irrigation conditions and drought stress can be a guide for growing plants in dry and low water conditions, the aim of this study was investigating of the effects of drought stress on morphological characteristics and quercetin amount, in different stages of plant growth of C. officinalis L. This research was conducted in Gorgan in a completely randomized factorial design, each treatment with 3 replications. The experimental treatments included three levels of stress (no stress, mild stress and severe stress) in pots under greenhouse conditions, at vegetative, pre-flowering, flowering, and fruiting stages. After determining the soil field capacity in the pots, the water content was calculated for control pots, and then its content was set at 2/3 for mild and 1/3 for drought stress. The pots were irrigated with the specified amount. After the treatments, plants were pulled from soil and their morphological traits including plant height, root length, stem length, leaf length, number of flowers, and flower diameter were measured. Moreover, their predominant flavonoid production (quercetin) was measured by liquid chromatography. Statistical analysis was performed SPSS software and means were compared using Duncan's multiple range test at 5% level. The results showed decreased plant height, leaf number and area and flower number and diameter, and increased root length by decreasing of soil moisture content at all stages of growth. The amount of quercetin increased in mild stress condition and decreased in severe stress condition at flowering and fruiting stages. The highest level of quercetin (59.11 mg g-1 dry weight) was belonged to mild drought stress at fruiting stage and the lowest level (41.05 mg g-1 dry weight) was belonged to severe drought stress at flowering stage. It can be concluded that plants produce more secondary metabolites in response to stress, and in severe stress, they produce fewer secondary metabolites due to lower plant growth rate.

Floriculture has become one of the vital profitable businesses in Indian agriculture. The important flowers which are internationally traded include lilium, tagetes, rose, tulip, chrysanthemum, carnation, tuberose, crossandra, etc. Estimation of yield at the time of harvesting of flowers is an important aspect in these floriculture businesses which help strategize their marketing. The present study thus focuses on Lilium and Tagetes (marigold), which are well-known cut and loose flowers, respectively. Cut flowers are harvested when buds start showing color while loose flowers are harvested depending upon the varieties when it attains full size. Conventionally, yield estimations are done manually by counting buds and flowers, which is often erroneous and time-consuming. This paper attempts to develop an automated system for counting Lilium buds and Tagetes flowers at the time of its harvesting using digital image processing techniques. The process implicates image acquisition, pre-processing, thresholding, watershed and finally buds/flower counting for yield estimation. The validation of the results has been done by comparing the results obtained through the manual method as well as by automated counting. The entire process was repeated four times with four different photos to judge the robustness of the techniques. The obtained result was 95.61% accurate for Lilium and 96.66% in the case of Tagetes, airing the possibilities of using the approach. The systematic workflow with pros and cons has been discussed in this paper.