جستجوی مقالات مرتبط با کلیدواژه « marigold » در نشریات گروه « باغبانی »

Given the economic importance of growing flowers and plants in the world, the use of new technologies and methods in the improvement of ornamental plants in order to market them can play a significant role in marketing of these products and their trade in the international markets. Marigold (Tagetes spp.), is an annual and essential plant that is cultivated as an ornamental plant in many parts of the world (Neher, 1968). But in recent years, marigolds have been used as a commercial source of essential oils, biological compounds, pigments and cosmetics (Anonymous, 1976), control of malaria mosquitoes (Wanzala and Ogoma, 2013), antihypertensive, anti-inflammatory, antidepressant, antimicrobial, antimicrobial (Senatore and Feo, 1999), and control of nematode (Prasad et al., 1992). Anther or microspore culture is known to be an effective method for producing haploid plants (Henry and De Baizer, 1980). Hybrid seed production requires pure line (as a parent), and the double haploid method can reduce the production period of pure lines to 5-6 years. Production of hybrid seeds in this valuable plant is of great importance, and the double haploid method can be important in this regard.
 
In the anther culture of marigold, a culture medium containing 0.2 mg/l of Naphthalene acetic acid and 1 mg /l of 6-Benzylaminopurine was used. In this study, the effect of genotype, bud size and mannitol on androgenesis induction of marigold anthers was evaluated during two separate experiments. A factorial experiment was conducted in a completely randomized design with two factors including genotype at 5 levels (T1, T2, T3, T4, T5) and bud size at three levels (3-5, 5-10 and 10-15 mm) for first experiment. The second experiment was also performed as a factorial in a completely randomized design with 3 replications. In the recent experiment, the first factor included the method of mannitol application and the second factor included the different concentrations of mannitol (0.1, 0.2, 0.3, 0.4 and 0.5 M). The factor of application method was in 2 levels: 1: adding different concentrations of mannitol to the solid culture medium and 2: pre-treating the anthers with the liquid culture medium containing different concentrations of mannitol for 24 hours. The T4 genotype was used in the second experiment.
 
In the first experiment, the effect of different bud sizes and 5 different genotypes on callus formation, mean number of shoot per anther, mean number of shoot per callus and percentage of complete plant regeneration in anther culture of marigold were studied. The results of this experiment showed that buds with the length of 5-10 mm have anthers which their microspores are at the proper growth and development stage for callogenesis and shoot production. The T3 and T4 genotypes, (both of them belonging to French species, Tagetes patula), produced the highest percentage of plant regeneration among the various cultivars. In the second experiment, we explored the impact of mannitol treatment on androgenic traits in marigold anther culture. Specifically, we examined two concentrations: 0.1 M and 0.2 M mannitol, both applied in the form of solid culture medium. Additionally, we investigated two concentrations, 0.0 M and 0.2 M mannitol, when applied as a pre-treatment in a liquid medium containing mannitol. These treatments yielded the highest percentage of callus formation. While the pre-treatment of anthers with a liquid culture medium containing 0.5 M mannitol led to the highest mean number of shoot per anther and the mean number of shoots per callus. Also, the pre-treatment with liquid medium containing 0.2 M mannitol showed the highest percentage of complete plant regeneration.
 
Results showed that in marigold, buds with the size of 5-10 mm contained microspores with mid-uninucleate stage to early bi-nucleate stage showed the highest response to the induction of androgenesis. Also, T3 and T4 genotypes belong to the French species showed the highest response to the regeneration. In another experiment, the pre-treatment of anthers with 0.2 and 0.5 M mannitol by using mannitol in a liquid culture medium for 24 hours, respectively showed the highest percentage of complete plant regeneration and the highest mean number of shoot per callus and anther. Chromosome counting results showed that 3 out of 5 examined plants were dihaploid and had 24 chromosomes in their root tip cells, while examined mother plants were tetraploid and showed 48 chromosomes in their root tip cells.

The aim of this study was to investigate the maturation time of rice husk compost and its effect on some substrate quality characteristics and growth indices of marigold flowers in greenhouse conditions. In this study, the time to produce complete compost was 90 days and sampling was done at 0, 30, 60 and 90 days. The bulk density indices, C/N, EC, pH and elements N, P and K were measured to quantitatively compare the compost properties. The results showed that compared to the available standard values, 90-day rice husk compost (RHC90) has better quality characteristics and is more stable than 60-day rice husk compost (RHC60). To evaluate the maturity of RHC60 and RHC90 with control in marigold planting, an experiment was conducted in a completely randomized design with 3 different substrates and 6 replications. The substrate consistsed of soil, sand and perlite and organic matter in equal proportions and control without organic matter. RHC60 substrate treatment showed the highest results on Marigold characteristics including leaf area, number of leaves, stem length, root volume and plant dry and wet weight,,while RHC9 0 treatment responded better for chlorophyll, mean leaf diameter and flower head diameter.  RHC90 treatment showed better yield in the plant and is therefore recommended as marigold substrate. RHC60 treatment is recommended in landscapes by considering its effects on reducing the production time and increasing yield and economic efficiency and also the appearance of flowers and the need for landscapes.

In order to investigate effect of humi-forthi biostimulator and L-arginine amino acid on growth, physiological and biochemical characteristics of marigold (Tagetes erecta) under drought stress, a factorial experiment based on a completely randomized design with three replications was carried out. The first factor was humi-forthi at three levels (0, 2.5 and 5 mg/l), the second factor was L-arginine at three levels (0, 1.5 and 3 mM), and the thirs factor was drought stress at three levels (100%, 70%, and 40% FC). Traits including the number of flowers, flower diameter, total chlorophyll content, SOD enzyme activities, andNPK concentrations were measured. The results indicated that drought stress, especially 40% FC, significantly influenced all morpho-physiological traits of marigold. There was observed a reduction flower diameter and number, chlorophyll content, and NPK under drought stress, whereas an increase was recorded for SOD activity and carotenoid. In most traits, 5 mg/l humi-forthi was more effective in respect to 2.5 mg/l and control. In addition, 3 mM L-arginine significantly had greater impact in respect to control and 1.5 mM. The interaction of humi-forthi, L-arginine and drought stress was significant on total chlorophyll, SOD activity, P and K (P≤0.05). The treatment of 5 mg/l humi-forthi + 3 mM L-arginine is the most effective treatment for alleviating the adverse effect of drought stress particularly 40 % FC.

Water deficit is one of the most important environmental factors that affects plant growth and development, and limits plant production. Water deficit negatively changes the balance between the production of reactive oxygen species (ROS) and antioxidant activity, producing oxidative stress. Sodium nitroprusside (SNP) commonly used as nitric oxide (NO) donor in plants. In orther to study the effects of different concentrations of Sodium nitroprusside (SNP), on drought tolerance of Marigold, this experiment has been carried out as factorial based on a completely randomized design in a greenhouse with 9 treatments and 6 replications. Treatments including 0, 100 and 200 µM SNP and three levels of drought stress, control (FC), moderate stress (80% FC) and severe (60% F.C.). The results of morphological, physiological and biochemical parameters showed that spraying Marigold flower with a concentration of 100 µM SNP increased tolerance of Marigold flower to drought stress through the effect on physiological and biochemical parameters and improved antioxidant enzyme activity (increased catalase). The highest stem length (40.01 cm), number of flower per plant (8.83), flower longevity (29 days), leaf relative water content (66.34% ) and total fresh weight (66.09 g), and the lowest ion leakage (28.12%) was found in plants treated with 100 µM SNP. Further, 100 µM SNP significantly increased average number of branches, leaf chlorophyll, dry and fresh weight of flower, stem and root dry and fresh weight compared with those in control. It was found that spraying with a concentration of 100 µM SNP could be effective in increasing tolerance of Marigold flower to drought stress.

Graden or bedding plants are suitable for landscape design purposes. Marigold (Tagetes spp.) is currently a popular landscape bedding and garden plant due to its color range and moderate tolerance to drought. Therefore, increasing flower number, flower diameter, and some other parameter related to bedding plants performance such as flowering period are veryimportant. Thus, a CRD -based factorial experiment was conducted to assess the effects of foliar application of some substances on growth, flowering and some biochemical characteristics of marigold. The seeds were sown in pots at the beginning of season. Foliar spray (4 times) was applied at 6-leaf stage and with 10 day intervials using thiamine, ascorbic acid and gibberellic acid (GA3) solely or in combination at 100 and 0 mg-1 with 5 replications. The results indicated the highest fresh and dry weight of shoot and root, the highest stem height, root length, stem diameter and flower diameter (0.87, 1, 1.5 and 1.62 fold, respectively), the highest photosynthetic pigments and reduced sugars were found in the combined treatment of these mentioned chemical, compared to control. Furthermore, parameters such as the average number of lateral shoots, chlorophyll index and flower number were considerably increased compared to control. A synergistic effect was also found when vitamins and GA3 were used simultaneously.

In recent years, global warming and the scarcity of water have led to the use of other sources of irrigation water, such as low-quality saline and recyceled waste waters. The aim of this study was to evaluate the effects of three irrigation water qualities (regular, waste, and saline well waters with EC of 0.3, 1.0 and 4.8 dS/m, respectively) and the growing media (soil and soil +10% v/v perlite) on characteristics of three marigold cultivars (Tagetes erecta L. ‘Climax’ and ‘Antigua’ and T. patula L. ‘Sophia’), in a pot experiment. All of the vegetative traits, except growth period and plant height had no significant differences in waste and saline water treatments. Irrigation with saline water significantly reduced all of the vegetative traits. Flowering priods in regular, waste, and saline water treatments were 76, 63, and 46 days, respectively. The highest and lowest values for the main flower duration, diameter and weight and the number of flowers per plant were observed in regular and saline water treatments, respectively. Flower yield per plant in waste and regular water treatments were statistically similar, but reduced in saline water by 35 and 39 %, respectively. Addition of perlite to soil, increased growth period and all of the vegetative and reproductive traits. Plant height and canopy shading area were the most different characters among the cultivars. Flowering period and all of the flower related traits of ‘Antigua’ were statistically more than ‘Climax’, but the values were close and except for number of flower per plant, were greatly reduced in ‘Sophia’. Compare to ‘Climax’ and ‘Antigua’ cultivars, ‘Sophia’ showed 61 and 68 % lower flower weight per plant.