Extension of vase life of cut orchids using ozonated water and 1-methylycyclopropene

Orchid industry has a particular situation within ornamental plants in Malaysia. As, 46% of total floriculture industry was occupied by orchid flowers in 2011. Most cut orchid flowers are ethylene sensitive in the spite of having acceptable longevity and postharvest life. When they are packed for export they show ethylene injury symptoms such as bud and floret abscission and short vase life. 1-MCP can control ethylene production and action and probably reduces the ethylene sensitivity. Another possible reason for the short span life may be microbial blockage in xylem conduits. Aqueous ozone can be a good candidate for improving the water conductivity in cut stems by its microbial growth inhibition effect. 1-mythylcyclopropane (1-MCP) and aqueous ozone were used for controlling ethylene sensitivity and inhibition of xylem blockage in two ethylene-sensitive cut orchids, Dendrobium ‘Darren Glory’ and Mokara ‘Calypso Jumbo’. Three experiments were conducted at Department of Crop science, Faculty of Agriculture, Universiti Putra Malaysia (UPM), Serdang, Selangor Darul Ehsan. In experiment one, inflorescences of 12 cut orchid hybrids consisted of six cut Dendrobium hybrids (Dendrobium ‘Darren Glory’, D. ‘Sonia Red’, D. ‘Sonia White’, D. ‘Sonia Bom’, D. ‘Shavin White’ and D. ‘Jacqueline Concert’ x D. ‘Rinappa’) and six Mokara hybrids (Mokara ‘Calypso Jumbo’, M. ‘Chao Praya Classic’, M. ‘Citi Gold’, M. ‘ Boy Blue’, M. ‘Red’ and M. ‘Chak Kuan Blue’) were determined for their ethylene sensitivity levels. Inflorescences were treated with 0 and 10 μL/L ethylene gas for 24 hours in 79 L chambers. The chambers were aerated and stems of flowers were trimmed and placed in PE bags containing vase solution [dіstіllеd water + 250 mg/L 8-hydroxyquіnolіnе cіtrаtе (8-HQC) + 150 mg/L citric аcіd + 4% sucrose, pH=3.5]. Weight loss, vase life, ethylene production and anthocyanin content and expression of ACC synthase and ACC oxidase genes of florets were determined. Results showed that exposure to ethylene caused reduction of vase life tremendously. This was manifested by epinasty, premature wilting and abscission in florets and buds for all hybrids. Weight loss and anthocyanin degradations increased when flowers were exposed to ethylene. After exposure to ethylene, higher expressions of both ACS and ACO genes were found in fully open florets. However, different hybrids showed distinct responses to ethylene sensitivities and degrees of deterioration. Therefore, they can be categorized into two groups, sensitive and less sensitive. Dendrobium ‘Darren Glory’, D. ‘Jaquelyne Concert’ x D. ‘Rinappa’, Mokara ‘Calypso Jumbo’, M. ‘Chаo Prаyа Clаssіc’(MCPC) and M. ‘Red’ exhibited the utmost epinasty, weight loss and anthocyanin content degradation in sepals and petals thus, can be considered as sensitive group while the rest were less sensitive. In the second experiment, the inflorescences of two very sensitive (Dendrobium ‘Darren Glory’ and Mokara ‘Calypso Jumbo’) and two less sensitive (D. ‘Sonia Bom’ and M. ‘Citi Gold’) hybrids that were determined in experiment first, were studied. Inflorescences were divided into two groups and placed in two 79 L chambers. For fumigation of 0 and 300 nL/L 1-MCP, a small vial containing 37.92 mg Ethylbloc was taped to the one chamber’s internal wall. Then, 190 μL/L deionized water was added to the vial. Both chambers were immediately sealed for 4 hours. Then inflorescences of each chamber divided into two subgroups and after labeling the four 39.5 L chambers inflorescences were placed inside them gently. The chambers were hermetically-sealed. Then, two separate 1μL/L ethylene gas, balanced with nitrogen, were injected into the one chamber of each subgroup. After 24 hours the chambers were opened and each inflorescence’s basal stem was trimmed to 12 cm from the first open floret. Then, each inflorescence was placed in the bottle with а cylіndrіcаl polyethylene bag containing 60 ml distilled water and kept in the laboratory at means temperature, relative humidity and light intensity of 25 oC, 78% and 6.57 μmol/m2/s, respectively. The results showed that weight loss in all four hybrids after 1-MCP fumigation even with exogenous ethylene treatment remarkably declined except MCG which did not show any variation to the responses of all treatments. Vase life responses of highly sensitive and less sensitive hybrids to the 1-MCP were positive but almost different. Maximum vase life extension was observed in highly sensitive hybrid (MCJ) about 59% with 300 nL/L 1-MCP treatment and minimum extension was occurred in less sensitive hybrid (MCG) around 39%. So it can be suggested that the effectiveness of 1-MCP on the control of ethylene sensitivity in highly sensitive hybrids was more. In the third experiment, effects of 1-MCP and aqueous ozone on postharvest quality of two very sensitive cut flowers; Dendrobium ‘Darren Glory’ and Mokara ‘Calypso Jumbo’ were studied. The inflorescences were treated with 0 and 300 nL/L 1-MCP. After four hours, the chambers were aerated and the stems were trimmed to 12 cm from the basal end of the first open floret. Each inflorescence was put into a bottle containing 250 mL of distilled water (control treatment) and 5.2 mg/L aqueous ozone.Ethylene production, microbial growth, bud opening, 1-aminocyclopropan oxidase activity (ACO) and vase life were measured. Results showed 1-MeCP can control the ethylene production within 5 day after harvest in both studied cut orchids very well and also ethylene production and ACO activity in D. ‘Darren Glory’ was higher than M. ‘Calypso Jumbo’. Aqueous ozone (5.2 mg/L) declined microbial (bacteria, fungi and yeast) growth when it used as the vase solution and every 24 hours replenished and consequently it was effective on decreasing xylem blockage and the micro-graphs from the xylem showed it clearly. In the forth experiment effects of 4 concentrations of 1-MCP and optimum concentration of aqueous ozone on postharvest quality of sensitive cut flower; Mokara ‘Calypso Jumbo’ were studied. The inflorescences were fumigated with 0, 100, 200, 300 and 400 nL/L 1-MCP. After four hours fumigation, the stems were trimmed to 12 cm from the basal end of the first open floret. First 30 inflorescences with and without 1- MCP fumigation were cut with scalpel into two parts: one had only buds and another one had only open florets. Stem ends were placed in distilled water and ozonized water and then used for ACC content and ACC oxidase activity measurements. Remaining fifty intact inflorescences were placed into the bottles each one, containing 250 mL of distilled water or 3.9 mg/L aqueous ozone based on the combination treatments. Ozonized water was renewed at every 24 hours, but for the rest treatments, vase water was not changed until end of vase life. The results showed that fumigation of the cut Mokara ‘Calypso Jumbo’ flowers with 100 nL/L 1-MCP, followed by using 3.9 mg/L aqueous ozone as the vase water could be recommended as the best postharvest treatments to maintain quality and extend vase life of MCJ orchid hybrids. In addition, these treatments for MCJ were very effective in extending vase live, increasing water uptake and percentage bud opening and also controlling the bacterial growth in vascular system Therefore, optimum postharvest treatments for the cut orchid flowers depended on hybrids. Pretreatment of the cut orchid flowers with 100-300 nL/L 1-MCP, followed by using 3.9 mg/L aqueous ozone as the vase solution could be recommended as the optimum postharvest treatments to maintain quality and extend vase life of both the DDG and MCJ orchid hybrids. In addition, 1-MCP pretreatment for MCJ was very effective in extending vase lives and increasing percentage bud opening. Additionally, aqueous ozone can effectively decreased number of bacteria in vase water and vascular vessels. Another important finding of this experiment was the cause of short vase life in the two cut orchid hybrids. The main reason for the short vase life was due to ethylene sensitivity of the cut flowers and not due to xylem blockage

Physiological and Morphological Responses of the ‘Dargazi’ Pear (Pyrus communis) to in vitro Salinity

Salinity is one of the most important factors limiting growth and production of plants worldwide. Improving tolerance to salinity in plants is the most effective way to increase performance. Influence of salinity on growth, physiological and biochemical responses of Pyrus communis ‘Dargazi’ explants was investigated in in vitro conditions. Explants were cultured on Murashige and Skoog (MS) medium containing 1 mg L-1 BAP (6-banzyl amino purine) and 0.1 mg L-1 NAA (Naphthaline acetic acid) supplemented with different sodium chloride (NaCl) concentrations 0 (control), 40, 80, 120 and 160 mM. With increased salinity, the fresh weight, dry weight, the number of leaves, shoot length, chlorophyll index, multiplication index, leaf relative water content and total protein decreased. In contrast, proline, soluble sugar and activity of catalase increased

Postharvest responses of cut Dendrobium orchids to exogenous ethylene

The time to senescence of flowers in Dendrobium hybrids is different and one of the major reasons for this variation in vase life can be related to differences in the level of ethylene sensitivity. This study was conducted to determine the sensitivity of six cutDendrobium hybrids to exogenous ethylene. The cut orchid inflorescences were treated with or without 10 µL/L ethylene gas for 24 h, and then placed in bottles containing a standard vase solution. Water loss, vase life, anthocyanin contents and ethylene production were determined after the treatments. The results indicated that different hybrids showed distinct variances in ethylene sensitivities and degrees of deterioration. Dendrobium ‘Darren Glory’ and D. ‘Jaquelyne Concert’ × D. ‘Rinappa’ exhibited the utmost hyponasty, weight loss and degradation of anthocyanin content in sepals and petals. Thus, these two hybrids were categorized as the very sensitive group. On the other hand, D. ‘Sonia Red’, D. ‘Shavin White’, D. ‘Sonia White’ and D.‘Sonia Bom’ showed lower sensitivity and hence were categorized in the less sensitive group. The results of this experiment and similar experiments to determine the resistant and susceptible cultivars to ethylene injury can be helpful in improving the postharvest life of cut orchid flowers

Postharvest responses of six cut Mokara spp. hybrids to exogenous ethylene

Ethylene-sensitive cut flowers despite having good shape and colour, display short vase life and usually after shipment, their ethylene injury would be very high, which is a negative point for exportation. The objectives of the study were first, evaluation of level of ethylene sensitivity and second, categorizing of six cut Mokara hybrids based on ethylene sensitivity: Mokara ‘Chak Kuan Blue’, M. ‘Chao Praya Classic’, M. ‘Calypso Jumbo’, M. ‘Boy Blue’, M. ‘Red’ and M. ‘Chitty Gold’. The inflorescences were treated with 10 µL/L ethylene gas for 24 hours before placing them in bottles containing standard solution [distilled water + 250 mg/L 8- hydroxyquinoline citrate (8-HQC) + 150 mg/L citric acid + 4% sucrose, pH=3.5]. Water loss, vase life, anthocyanin contents and ethylene production were determined after treatments. Expressions of 1-aminocyclopropane-1-carboxylic acid synthase (ACS) and oxidase genes (ACO), before and after exposure to ethylene in the lips of third florets were also determined using semi-quantitative RT-PCR method. Ethylene caused tremendous reduction of vase life with an average of 59%, indicating ethylene sensitivity in studied Mokara cut hybrids. This was displayed by florets and buds wilted and dropped in all tested hybrids. Weight loss and anthocyanin degradation increased when the flowers were exposed to ethylene 11.5 and 16%, respectively. Both genes were expressed in fully open florets, but after exposure to ethylene, the levels of expressions were higher in all hybrids. However, different hybrids showed distinct variances in ethylene sensitivities and degrees of deterioration. M. ‘Calypso Jumbo’ and M. ‘Red’ exhibited the utmost anthocyanin degradation in sepals and petals and declined in the length of vase life. Thus, these two hybrids were categorized as the very sensitive group. M. ‘Chak Kuan Blue’, M. ‘Chao Praya Classic’, M. ‘Boy Blue’ and M. ‘Chitty Gold’ categorized as less sensitive group

Vibrio Parahemolyticus in the Wastewater of Kermanshah City

آب و فاضلاب                                                                                                                                                                                                               شماره 51- سال 1383     Municipal wastewater is one of the most important pollution sources for water supply resources. Soil, vegetable, and food material are exposed as well. Identification and enumeration of pathogenic agents particularly pathogenic Vibrios are beneficial for control and prevention planning of the infectious diseases. This research carried out to identify the distribution of the recognized pathogenic Vibrios emphasizing on identification of Vibrio cholerain the wastewater of city of Kermanshah in 2001. Population of city of Kermanshah was estimated over 713000 and produced wastewater was approximately 150 l/cap/d. The method of study was cross-sectional descriptive. Sampling procedure was adopted from standard Methods for the Examination of water and wastewater, and the method for Vibrios identification was according to finegold 1990. There were 8 discharge outlet domestic wastewaters, which had been chosen as sampling sites. Samples were collected weekly in randomized manner in day time. Although 288 samples should be collected statistically, 339 samples were collected and analyzed. The results indicated that site 7 with 5 positives, sites 4 and 8 with 3 positives, site 5 with 2 postitives and sites 2, 3 and 6 with one positive suspected to vibrio pathogens. However, not any Vibrio detected in site 1. The most positive samples were seen in spring, late summer and early autumn. The positive results were detected in May, June, September, and October. Among samples which have been detected as a positive could be likely Vibrio Parahemolyticus accourding to the differentiation tests. Vibro chloral was not found. It looks like the presence off vibrio parahemolyticus was due to wastewater discharged from sea food markets areas. So it has been suggested that this relationship could be considered through analytical study using PCR for detection of Vibrios

The effect of apprenticeship on the knowledge and function of students of environmental health engineering

Introduction: Creating optimized opportunities for experiential learning and practical training is an important factor that improves the quality of education. This study aims to identify and analyze the mechanism of improving apprenticeship course for the students of Environmental Health Engineering at School of public Health in Kermanshah. Methods: This study is based on comparing the quality of education in apprenticeship courses by before – after study. The participants were the students who passed the apprenticeship course in the first semester of 2014 -2015 (32 students). The SPSS v.16 and the statistical T-test were used for statistical analysis. Results: The average scores for men before apprenticeship was 2.02±0.41 and after the apprenticeship was 2.82 ±0.44, and the average scores for women before and after the apprenticeship were respectively 1.9±0.34 and 2.84±0.37, respectively. The level of training during the apprenticeship course influence on increasing knowledge in the students of environmental health engineering. Conclusion: Analyzing the effective factors on improving the apprenticeship course influenced by the following factors: implementation method of effective roles of the educating units, playing an effective role in apprenticeship course, supplementary training activities during the serving time and playing an effective role be apprentices. Keywords: Theoretical knowledge; Apprenticeship; Environmental Health Engineering &nbsp

Removal of turbidity and organic matter from car wash wastewater by electrocoagulation process

Car wash effluent is one of the important threats that can contaminate water resources for drinking, agriculture and industrial uses in Iran. The purpose of this study was assessment and analysis of the efficiency of the electrocoagulation process in the removal of turbidity and organic matter from car wash effluent. Data were taken through laboratory scale and sampling from different car wash sewages of Ahvaz, Iran. In this experimental study, we used a bipolar method to convert alternative electricity to direct current. The important factors of our study were pH, electrical potential, voltage and reaction times. Results show that the percentage of turbidity removal in the electrocoagulation (EC) with an aluminum electrode (E) with an optimum pH = 7 were 75 and 99.59 in 10 and 30 voltages, respectively. According to results, the percentage of chemical oxygen demand (COD) removal in the electrocoagulation with an iron electrode with an optimum pH = 3 were 67 and 94 in 10 and 30 voltages. Consequently, electrocoagulation is a comparatively suitable process for turbidity and organic matter removal from car wash wastewater