Journal of Ornamental Plants
Volume:7 Issue: 4, Autumn 2017

The effect of potash biofertilizer and chemical fertilizer was studied on quantitative and qualitative traits of periwinkle in a factorial experiment based on a Randomized Complete Design with three replications, 48 experimental units, and two factors: (1) different methods of potash bio-fertilizer application at four levels of control (B0), seed inoculation (B1), root inoculation (B2) and seed inoculation × root inoculation (B3), and (2) different rates of potassium on fertigation at four levels of 0 (K0), 100 (K1), 200 (K2) and 300 mg L-1 (K3). It was found that the longest shelf life of 35.58 days was related to the treatment of root inoculation × 100 mg L-1 K. The highest number of auxiliary branches (3.66), number of leaves (42.88), plant fresh weight (17.69 g), number of flowers (4.46), and chlorophyll a (10.61 mg g-1 F.W.) were obtained from the treatment of seed inoculation × 300 mg L-1 K. The treatment of root inoculation × 200 mg L-1 K was the best treatment for plant potassium content (28.9 mg kg-1). The highest petal anthocyanin content amounted 178.04 mg 100 g-1 D.W. was observed in the treatment of ‘seed inoculation × root inoculation’ × 0 mg l-1 K. The best treatment of enhancing of qualitative and quantiative traits of periwinkle was seed inoculation × 300 mg L-1 K.

In vitro microbial contaminations are the most serious problems in plant tissue culture. Initial attempts for micropropagation of Dionysia tapetodes, a beautiful alpine cushion plant from north-east Iran, led to 100% explants contamination. Hence, the present study was conducted to develop an efficient surface sterilization protocol for in vitro culture of field collected D. tapetodes using combinations of different disinfection agents including sodium hypochlorite (NaOCl), ethanol and mercuric chloride (HgCl2) in different concentrations and exposure times. The most effective sterilization treatment with 91.6% healthy explants was the application of 0.1% mercuric chloride for 4 min. However, mercuric chloride in higher concentration (0.2%) was toxic to explants tissues and resulted in 41.66% necrosis. Moreover, the results indicated that in spite of being a general disinfectant in tissue culture studies, NaOCl was not as effective as mercuric chloride in elimination of microbial contaminations and led to 75% total infection when used in concentration of 3% for 15 min. The current experiment represented a potential method for disinfection of D. tapetodes and provided aseptic and clean explants for future in vitro culture studies.

Nitrogen is a crucial nutrient affecting plant growth and development and its addition to the soil (as chemical or organic form) influences plant growth characteristics. One experiment was conducted as a factorial based on RCBD with two Chrysanthemum cultivars (‘Fred’ and ‘Angel’( and two N-fertilizer sources [Urea (750 and 1500 g/ha and Nitroxin 7.5 and 15 L/ha] used as fertigation method beside control treatment with three replications. The results revealed that the greatest petals carotenoids content was belonged to 15 liter/ha Nitroxin and the least data for total phenolics was recorded in the control treatment with ‘Angel’. Urea at 1500 g/ ha increased the total phenolics content. The high chlorophyll a content was obtained with Nitroxin (15 L/ ha) with ‘Fred’ and Urea (1500 g /ha) with ‘Angel’. The least chlorophyll b content was recorded with 1500 g / ha Urea at ‘Angel’. Roots dry weight (15 L/ha Nitroxn), stem dry weight (15 L Nitroxin and 1500 g /ha Urea) were positively affected in ‘Fred’. Fertilizers application positively affected root fresh weight in both cultivars. The highest content of anthocyanin (19.3 µmol g-1 FWt) was recorded in ‘Angel’ cultivar. Anthocyanin content was also influenced by 1500 g / ha Urea (19.2 µmol g-1 FWt) and 15 L/ha Nitroxin (18.4 µmol g-1 FWt). The highest amount of shoot number (12.6) was recorded in ‘Fred’ cultivar. With any increase in the fertilizer levels, flowers fresh weight and shoot numbers were significantly increased.

Salinity is one of the greatest environmental challenges facing plant growth and development in the 21st century. Salicylic acid (SA) is a phenolic compound and signal molecule involved in the regulation of plants responses to biotic and abiotic stresses. This greenhouse experiment was conducted to determine effects of SA application on Kentucky bluegrass (Poa pratensis L.) responses to salinity stress. The three salinity levels (0, 40 and 80 mM NaCl) were applied in nutrient solutions, and foliar SA treatments (0, 1 and 2 mM) were applied at 2-weeks intervals. The study was carried out as a factorial experiment based on completely randomized experimental design with four replications. Salinity reduced root and shoot dry weight, visual turf quality, leaf chlorophyll and potassium content, whereas electrolyte leakage, proline and sodium content were increased with salt concentration in nutrient solution. Salicylic acid application ameliorates adverse effects of salinity in all factors and this effect was more pronounced in 80 mM NaCl. In terms of root dry weight, leaf sodium and proline content as well as electrolyte leakage, SA application at 2 mM had better results than 1 mM. These results suggest that further studies are required to find proper SA application rate in different salinity levels.

The present study explored the efficacy of Bacillus spp. and protease production for biocontrol of the root-knot nematode Meloidogyne javanica in African violet media. Among 100 bacterial isolates from various soils, the highest nematode mortality was observed for treatments with isolate GM-18, which was identified as Bacillus subtilis based on cultural and morphological characteristics and 16S rDNA sequencing analyses. The Bacillus spp. showed nematicidal activity 74.01 to 28.33. Strain GM18 showed the most inhibitor zone in medium containing casein (13 mm) and nematicidal activity in our tests targeting Meloidogyne javanica. The effect of different variables such as time (1-24 h), pH (7- 8.5), and temperature (25- 37 °C) on the protease production was checked. The maximum enzyme production was noted when B. subtilis GM18 was grown on mineral medium and incubated at 31°C for 12 h with initial pH = 8. Three protease inhibitors that had the greatest influence on EDTA were studied. Protease produced by B. subtilis GM18belonged to different groups.

A serious problem in cultivation of ornamental plants is a lack scientific and applied program in fertilization, so that the plant nutrition focused on growth medium. A randomized completely design with 8 different fertilization methods with the use of ammonium sulphate, potassium sulphate, di ammonium phosphate, ferrilene and kristalon was conducted in three replications in a greenhouse of Chaboksar, Guilan, Iran. The height of bush, number of lateral branches, floor distance, number of floor, fresh weight of root and shoot, total fresh and dry weight of root and shoot were measured. The results showed that the growth of plant increased in a treatment including foliar spray of ferrilene and kristalon fertilizers in 1:1000 ratio for three times. In treatment of ammonium sulphate, potassium sulphate and di ammonium phosphate as base fertilizers amounted 2, 1 and 0.5 g per pot, respectively, the growth traits of plant was same to ferrilene and kristalon treatment. In conclusion, the highest plant growth obtained of a treatment including foliar spray of ferrilen and kristalon in 1:1000 ratio for three times.