The effectiveness of clove oil, its fractions, and clove oil-based fumigant tablet formulations, against Tribolium castaneum (Herbst)

Indonesia has seen an increase and widespread reports of resistance among stored-product insect pests to phosphine. The use of Syzigium aromaticum (clove oil) as an alternative fumigant may be a useful strategy to control infestation by phosphine-resistant varieties of stored-product insects. The objective of this study was to examine the effectiveness of whole (unfractionated) clove oil as well as its component fractions as a fumigant and repellent against the red flour beetle (Tribolium castaneum (Herbst)), and to develop a simple fumigant formulation for this purpose. The experimental design used to test the effectiveness of clove oil and its fractionation was a completely randomized design (CRD). Meanwhile, testing the effectiveness of tablet formulations was carried out by factorial CRD. Fumigation test results gave LD50 and LD95 values of 0.234 and 1.142 ml/l respectively, for crude clove oil used in a fumigation chamber against T. castaneum. An n-hexane fraction of clove oil tested under the same conditions was more lethal, causing 95% mortality of T. castaneum at the dose of 0.801 ml/l during fumigation. Finally, tablets containing a set proportion of clove oil and naphthalene (1:1) reached LD91 against T. castaneum after 7 days’ fumigation.

Effectiveness of Ethyl Formate as a Fumigant of Blattella germanica and Periplaneta americana (Blattodea: Ectobiidae, Blattidae) in Cross-Border Trade Transportation

Cockroaches cause problems as pests not only locally in residential areas but also internationally, as they can disperse across borders in transport vessels. We investigated the effects of the ethyl formate (EF) fumigant on all developmental stages of Blattella germanica and Periplaneta americana. For B. germanica eggs, the hatching inhibition rate increased directly proportionately with the increasing treatment concentration of EF, but the 100% control was not observed. P. americana eggs did not show any fumigation effect, even after exposure to 60 mg/L of fumigant in a 12 L desiccator. Adults and nymphs of the two species showed various fumigation effects dependent on the concentration in the 12 L desiccator. When EF was applied at the lethal concentration for 99% mortality (LCT99) values of 35 mg/L for 4 h (78.5 mg·h/L) and 60 mg/L for 2 h (70.8 mg·h/L), respectively, adults and nymphs of both species had 100% mortality in a 0.65 m3 fumigation chamber with a 20% loading ratio. However, no significant difference from the control was observed in the egg stage of either species of cockroach. The results of this experiment indicate that EF can be used as a fumigant for cross-border transport vessels if the control period occurs during the cockroach developmental stage and continuous refumigation is performed.

Nitrogen oxides as a factor in the variability of chlorophyll content in leaf tissues of Salix kochiana Trautv. at different stages of vegetation

In this work, the variability of the content of chlorophylls in the tissues of the plant leaves of the introducedspecies Salix kochiana in response to the action of low doses of nitrogen oxides was determined. To set up the experiment,a fumigation chamber was used to simulate environmental pollution with nitrogen oxides, concentration 0.5; 1.0; 1.5 and2.0 units of the maximum one-time MPC. It was found that the relationship between the dose of the operating gas and thechlorophyll content is non-linear. At the beginning of the growing season, under the influence of nitrogen oxides with aconcentration of 0.5 and 1.0 MPC, the chlorophyll content increases sharply (1.3 times), a further increase in the dose ofthe operating gas to 1.5 and 2.0 MPC leads to a decrease in the value of this indicator to background level. At the end ofthe growing season, the effect of nitrogen oxides with a concentration of 0.5 and 1.0 MPC, on the contrary, is accompanied by a sharp decrease in the content of chlorophylls (1.7 times), and an increase in the dose of the active gas leads toan increase in the value of this indicator, but its level remains significantly lower than the background. The interpretationof the obtained data from the point of view of the theory of stress makes it possible to characterize the response of Salixkochiana plants at the beginning of the growing season as a stage of the primary stress reaction, at the end of the growingseason as a stage of resistance, which makes it possible to recommend the studied species for landscaping areas with a similar nature of atmospheric pollution.

Finishing Properties of Poly Urethane Coating on Bleached and Ammonia Fumigated Mango Wood Surface

Aims: The impact of bleaching chemicals on the gloss and film thicknesses of poly urethane (PU) coated surface of mango wood (Mangifera indica) with ammonia fumigation and an exposure towards sunlight was investigated Study Design: Thirty six wood samples of size 10.6 cm (length) C 7.62 cm (width) were prepared from 2.5 cm thick kiln dried mango wood (Mangifera indica). Specimens were divided into six groups, each group having 6 samples for the study. Place and Duration of Study: The experiment was carried out in year 2016 at the Laboratory of Forest Product Division, Forest Research Institute, Dehradun, Uttarakhand, India. Methodology: All the samples were sanded with 80 grit size sand paper and coated with poly urethane. Two chemicals were used for bleaching purpose like an aqueous solution of oxalic acid (H2C2O4) was prepared with 30% concentration (by mixing 42.9 g of the solute in 100 ml of hot water) and a commercially available Hydrogen peroxide (H2O2) was used as such (30%). For the purpose of bleaching, these chemicals were applied on to the sanded surfaces using brush at room temperature. The bleached sample surfaces were allowed to dry before proceeding to the next step. The PU (Poly Urethane) coated samples were treated with ammonia fumigation before and after bleached with the two chemicals. Ammonia fumigation was carried out in a fumigation chamber for 24 hours for all the samples (except T1). Results: On exposure to natural sunlight for 60 hours, all the samples showed reduction in film thickness in PU coating but in a wide range of 2.8 % to 11.4%. The highest loss of coating thickness was shown by samples which were neither fumigated nor bleached. Among the fumigated samples, those bleached with oxalic acid resulted in high film thickness loss. Samples bleached with hydrogen peroxide after ammonia fumigation resulted in least film thickness reduction. Both ammonia fumigation and bleaching in general brought down the original gloss of poly urethane coating. The gloss value reduced as expected on exposure to sunlight. Bleaching by hydrogen peroxide prior to ammonia fumigation resulted in highest loss in gloss Conclusion: The un-fumigated and unbleached surface resulted in minimum gloss reduction due to long exposure to sunlight.

RANCANG BANGUN ALAT PENGASAPAN IKAN DENGAN SIRKULASI ASAP TERSEBAR MERATA

The processing of smoked fish that is carried out by the XIII Koto Kampar community is still relatively simple, the weaknesses caused by traditional fish smoked include the appearance of being less attractive (partially charred) difficult temperature control and polluting the air. In this research, a fish smoking system was designed using and oven model with a separate combustion chamber, the smoke is flowed through a pipe equipped with a filter and piping design to circulate the smoke evenly to the smoke cabinet. Retrieval of test data in the form of; Efficiency of smoking time by measuring temperature on each shelf and air humidity (RH) in the fumigation chamber, taking proximate content test data to determine moisture, ash, protein and fat content. Temperature testing for 480 minutes while maintaining the temperature between 30-40 ◦C. Humidity at 55% during the curing process and moisture content from 65-48%.

Fumigation Activity against Phosphine-Resistant Tribolium castaneum (Coleoptera: Tenebrionidae) Using Carbonyl Sulfide

Phosphine resistance is occurring among stored-grain pests worldwide. This study investigated the fumigation activity of phosphine (PH3) and carbonyl sulfide (COS) against domestic strain (d-strain) Tribolium castaneum, resistance strain (r-strain) T. castaneum and Oryzaephilus surinamensis. All developmental stages of the pests were exposed to two fumigants (PH3 and COS), and the fumigation activity according to the dose and exposure time was evaluated in a 12-L desiccator and 0.5 m3 fumigation chamber. The rice sorption rate and quality following exposure to thetwofumigants were evaluated. The mortality was 2.9% in r-strain T. castaneum, 49.5% in d-strain T. castaneum and 99.2% in O. surinamensis when 2 mg/L PH3 was used in a 12-L desiccator for 4 h. However, all pest developmental stages showed 100% mortality after 24 h of exposure in the 0.5 m3 fumigation chamber, except for the r-strain T. castaneum. A mortalityof 100% was observed in all of the r-strain T. castaneum developmental stages at an exposure time of 192 h. For COS applied at 40.23 mg/L and 50 g/m3 in the 12-L desiccator and the 0.5 m3 fumigation chamber, respectively, 100% mortality was observed across all developmental stages regardless of species and strain. The sorption of COS was 10% higher than that of PH3, but there was no significant difference in rice quality compared to that in the control. Therefore, this study suggests that COS can be used for controlling T. castaneum resistant to PH3.

Effectiveness of Nitrogen Dioxide Fumigation for Microbial Control on Stored Almonds

ABSTRACT Quality of stored almonds is compromised by insect infestations and microbial contamination. Nitric oxide (NO) is a potent fumigant for postharvest pest control on fresh and stored products. NO fumigation must be conducted under ultralow oxygen conditions, and it always produces nitrogen dioxide (NO2), depending on the O2 level in the fumigation chamber. NO and NO2 have proven antimicrobial effects but have not been tested for efficacy against microbes in almonds. We evaluated, in this study, fumigation of unpasteurized almonds with NO2 at different levels for inhibition of bacteria and fungi. Almonds were fumigated with 0.1, 0.3, or 1.0% NO under ambient O2 to generate 0.1, 0.3, or 1.0% NO2 conditions; the fumigation treatments lasted 1 or 3 days at 25°C. GreenLight rapid enumeration tests on diluted wash-off almond samples from NO2 fumigation treatments showed either greatly reduced microbial loads or complete control of microorganisms, depending on NO2 concentration and treatment duration. NO2 fumigation was more effective against fungi than against bacteria. These results suggest that postharvest NO fumigation with proper levels of NO and NO2 can be used for insect and microorganism control on stored almonds. HIGHLIGHTS

Comparison of the Efficacy and Phytotoxicity of Phosphine and Ethyl Formate for Controlling Pseudococcus longispinus (Hemiptera: Pseudococcidae) and Pseudococcus orchidicola on Imported Foliage Nursery Plants

The fumigation activity of phosphine (PH3) and ethyl formate (EF) and their phytotoxicity to 13 imported foliage nursery plant species were evaluated. The lethal concentration and time (LCT99) values of the PH3 indicated that the susceptibility of the nymphs (3.95 and <0.45 mg·h/liter, respectively) was higher than that of the adults (5.29 and 3.66 mg·h/liter, respectively) of two mealybugs [Pseudococcus longispinus (Targioni-Tozzetti) and P. orchidicola Takahashi]. The highest concentration reduction rate of PH3 and EF on the 13 foliage nursery plants in the 12-liter desiccator was 41.5% for Heteropanax fragrans and 71.7% for Schefflera arboricola, respectively, which indicates that PH3 has a lower sorption rate than EF. The phytotoxicities of PH3-treated foliage nursery plants did not significantly differ from those of the nontreated plants, but EF caused phytotoxicity in 11 foliage nursery plants a week after treatment. When the exposure time of PH3 increased to 24 h, the adults and nymphs of both mealybug species showed 100% mortality in the 0.5 m3 fumigation chamber. In the 10 m3 fumigation container used in the field, there was 100% mortality of both mealybugs after treatment with 2 g/m3 PH3 for 24 h at 16°C. These results indicate that EF is not a suitable mealybug fumigant due to its high sorption and phytotoxicity to foliage nursery plants, despite fumigation activity against the two species. However, PH3 seems to be suitable for mealybug fumigation in foliage nursery plants and can be used as a substitute for methyl bromide.

Design to Build A Shallots Drying House with Fumigation in District Tanah Miring

The purpose of this study was to make a simple shallots drying house design with fumigation so that dried shallots were obtained in accordance with the Standar Nasional Indonesia (SNI). The method used in this study is the temperature measurement in the smoke house. The benchmark in testing the smoking house is the temperature used in the room at the smoke house with the construction of a small scale permanent building. The temperature that shallots have to accept is 35-40oC. Temperature data obtained from measurements at 3 observation points in the smoke house for heat transfer analysis. The test results on the design of the smoke house with a shelf design located 2 meters from the ground floor showed that convection heat transfer in the fumigation chamber was stable so as to produce dry shallots with a weight loss of 30%.

Synergistic Effect of Phosphine and Carbon Dioxide on the Mortality of Tribolium castaneum (Coleoptera: Tenebrionidae) in Paddy

Phosphine (PH3) is widely used as a fumigant for the control of stored product pests. Indiscriminate use of PH3 leads to the development of resistant strains. Thus, an experiment was conducted in a laboratory scale fumigation chamber to determine the synergistic effect of carbon dioxide (CO2) and PH3 on the mortality of Tribolium castaneum during fumigation of paddy. PH3 gas generation varies depending upon grain moisture content and dosage of PH3 used for fumigation treatment. Thus, the maximum PH3 concentration with respect to saturation time was achieved when paddy were treated with 98% CO2 + 3 ppmPH3 at 17% moisture content, leading to a quick mortality of different life stages of T. castaneum with minimum LT50 and LT99 value. Among the different stages of T. castaneum, pupal stage was more resistant to all the treatments compared to larva and adult stages. PH3 residues in all the treatments were below the recommended level and it can be considered as safe for consumption.