Journal of Ornamental Plants
Volume:10 Issue: 3, Summer 2020

An experiment was conducted at the Floriculture Research Field of Horticulture Research Centre (HRC), Bangladesh Agricultural Research Institute, Gazipur, Bangladesh during April, 2015 to February, 2017 to find out the suitable planting materials for specific tuberose genotype for growth, flowering and bulb production of tuberose. Individually both genotypes showed better performances for some specific parameters and large bulb showed best results among different planting materials. The genotype TR-001, single variety produced the longer plant and spike (49.37 and 85.04 cm, respectively) and also the heavier stick (72.14 g). Alternatively, TR-004 which is semi-double variety obtained the longer rachis (32.12 cm) and the maximum florets/spike (44.38). In case of bulb and bulblet production, TR-001 produced the heaviest and the largest bulb (19.9 g and 2.89 cm, respectively) while TR-004 produced the maximum bulblets/plant and also the highest bulblet weight/plant (18.39 and 33.88 g, respectively). Considering the nature and size of tuberose bulb, the large bulb demonstrated the longest rachis (33.34 cm), the maximum florets/spike (45.54), the heaviest flower sticks (76.25 g), the maximum number of bulbs/plant (6.70), the heaviest and the largest bulb (22.55 g and 3.12 cm, respectively) and also the maximum number and weight of bulblets/plant (22.55 and 38.53 g, respectively). There were no significant variations among the various combination of tuberose varieties and planting materials on growth, flowering, bulb and bulblet production of tuberose. Besides, mother/old and medium sized bulb showed also statistically similar performances in respect of rachis length, florets/spike, bulbs/plant, weight and diameter of bulb and bulblets/plant. So, mother/old bulb of any tuberose variety can also be used for the commercial production with the large and medium sized bulbs.

Bougainvillea (Bougainvilleaspectabilis) is used for planting in the landscape because of their beautiful and colorful flowers. The easiest and cheapest technique to propagate this plant is by cuttings; however the cuttings of this plant are not easily rooted and require the special treatments, including the use of auxin. For this purpose, an experiment was performed in Completely Randomized Design with 15 treatments and four replications and the characteristics such as root and shoot length, root and shoot number, root fresh and dry weight, and the rooted cuttings percent were evaluated. The results showed a statistically significant difference among the used treatments. The use of 400 mg/L indolic-3-butyric acid (IBA) for 24 hrs dipping led to improve rooting parameters particularly the rooted cuttings percent. However, the use of 1000 mg/L IBA for 20 s quick dipping also had satisfactory results, which can be introduced as a suitable treatment due to the reduction of application time and labor costs. Adding substances similar to ascorbic acid (AsAc) and hydrogen peroxide (H2O2) also improved some traits such as the root length, root fresh weight and the number of shoots. In general, the use of high concentrations of IBA (2000 mg/L), which are used by quick dipping with the use of pre-treatment with AsAc and H2O2 can lead to improve rooting traits in bougainvillea cuttings. When the cost of the plant growth regulators is important, the use of the low-concentration of IBA (400 mg/L) by long-term dipping (24 hrs) can be effective for Bougainvillea cuttings.

The predatory mite Amblyseius swirskii Athias-Henriot is one of the most common biological-control agent of different mites and insect pests, such as two-spotted spider mite and greenhouse whitefly. To evaluate A. swirskii potential role in controlling three pest species, the present survey investigated the life history of this predatory mitewhen fed on eggs of Tetranychus urticae, Trialeurodes vaporariorum and Carpoglyphus lactis under laboratory conditions (25 ± 1°C, 70 ± 5% RH and 16L: 8D). Results showed that the predator mite is able to feed and complete its development on the above mentioned pest species. The predator displays particularly high capacity for population growth when fed on T. urticae and C. lactis, therefore it be able to provide an effective control of these pests in the gardens and the greenhouses. When T. vaporariorum was fed, significantly, increase in development and pre-oviposition times, and a reduction in oviposition period and fecundity were observed. In addition, the estimated life table parameters of A. swirskii including r, λ and R0 significantly descended when the predator fed on the whitefly. Our results showed that this predatory mite has an effective ability as an effective biological control agent for T. urticae, C. lactis and T. vaporariorum in greenhouse.

The current methods of turfgrass evaluations are often based on human-based assessment methods. However, eliminating subjective errors from such evaluations is often impossible. This research compared the accuracy of human-based and digital image processing-based methods for quality assessment of turfgrasses. Four turfgrass plots were evaluated using the two mentioned methods. In the human-based method, 20 evaluators (10 women and 10 men) and in the image-based method, a digital camera with an artificial and controlled light source were used. This experiment for the first time evaluated the two qualitative characteristics of turfgrass texture and weed growth tolerance using a specific image processing-based technique and the common human-based evaluation method. Further, total coverage, color, and living coverage of the turfgrasses were compared with the two methods. The results of the human-based assessment method showed a wider range and higher standard deviations than that in the image processing method, which seems to be due to the differences between the human's evaluators and errors caused by the human mind. The results also emphasized the accuracy and ease of application of the image-processing-based method. This outcome can have applications for developing a mechanized system for turfgrass quality evaluation across the world.

Paclobutrazol (PBZ) is one of the most important triazole compounds. This compound increases plant tolerance to environmental stresses. A study aimed to investigate the effects of PBZ on morphological and biochemical traits of euonymus (Euonymus japonicas) exposed to NaCl stress. Plants were treated with three levels of PBZ (0, 500 and 1000 mg L-1) and four levels of NaCl (0, 50, 100, 150 mM). Morphological characteristics, electrolyte leakage (EL), chlorophyll content and antioxidant enzyme activity were changed by treatment with PBZ and NaCl stress. As compared to control plants, at 1000 and 500 mg L-1 PBZ, a decrease in height of 22.8% and 10.44% was observed, respectively. The highest number of lateral shoots was recorded in 1000 mg L-1 PBZ (non-salt-treated). The interaction of salinity and PBZ on shoot fresh weight was significant. At 150 mM NaCl + 1000 mg L-1 PBZ, shoot fresh weight increased by 30% compared to 150 mM NaCl. PBZ treated plants had highersuperoxide dismutase (SOD) activity than non- PBZ-treated plants. 1000 mg L-1 paclobutrazol was the best treatment for increasing the activity of this enzyme. PBZ mitigated the salinity stress and reduced EL of euonymus. Compared with 150 mM NaCl alone, the EL decreased by 24.4% in 1000 mg L-1 PBZ + 150 mM NaCl. According to the results of this study, it can be concluded that PBZ can be effective in tolerating euonymus to 150 mM NaCl.

In order to study the effects of biological and chemical fertilizers on quantitative and qualitative yields of coneflower, an experiment was carried out in agricultural farm research on Parsabad in Ardebil. The experiment was as factorial based on a randomized complete block design with four replications. Experimental factors included N fertilizer (N0 = 0, N1 = 75 and N2 = 150 kg ha-1) and Azotobacter (inoculation with A. chroococcum bacteria SW22 strain = B1and non–inoculation = B0).The morphological traits such as plant height, number of lateral shoots, shoot fresh and dry weight, root fresh and dry weight, number of flowers per plant and phenol, nitrogen (N) and phosphorus (P) concentration were measured. The results showed significant effects of the treatments on the growth parameters. Inoculum with Azotobacter + 75 kg N ha-1 improved important parameters such as shoot dry weight (40.42%), root dry weight (60.02%), and number of flower plant-1 (65.68%). Additionally, phenol, N and P concentration in plants treated with the Azotobacter + 75 kg N ha-1 were 25.11%, 34.6% and 39.8% higher than the control plants. The results indicate that using biological fertilizers is a good choice to reduce the use of chemical fertilizers as an important tool to contribute to a sustainable agriculture.