Spray Interval Research Articles

Compatibility of Metarhizium anisopliae and Beauveria bassiana with insecticides and fungicides used in macadamia production in Australia.

Integrating fungal biocontrol agents into crop protection programs dominated by synthetic pesticides is an important first step towards developing an integrated pest management (IPM) program; however, their successful integration relies on an understanding of how their performance may be impacted by the remaining agrochemicals deployed for managing other pests and diseases. In this study we tested 10 formulated pesticides used in macadamia production at different concentrations to determine their effects on the germination, mycelial growth and sporulation of Metarhizium anisopliae and Beauveria bassiana in vitro. Further tests with laboratory-grade actives of the noncompatible pesticides were conducted to determine whether any antagonistic effects were caused by the active constituent or by formulation additives. At their registered concentrations, formulated trichlorfon, acephate and indoxacarb were compatible with M. anisopliae, whereas B. bassiana showed compatibility with formulated trichlorfon, acephate, indoxacarb, sulfoxaflor and spinetoram. Bioassays using laboratory-grade active constituents indicated that the adverse impact of formulated beta-cyfluthrin on both fungal species and that of formulated methidathion on B. bassiana is probably due to components of the emulsifiable concentrate formulations rather than their active constituents. Diazinon was the only insecticidal active that showed high toxicity to both fungal species. The two fungicides, carbendazim and pyraclostrobin, were toxic to both fungal species at all tested concentrations. Our results identify which pesticides used on macadamias in Australia are compatible and incompatible with entomopathogenic fungi. Future studies on pesticide degradation rates will help define the spray intervals required to eliminate these adverse effects.

Efficacy of Conventional Fungicides for Downy Mildew in Field-Grown Sweet Basil in the United States.

Application of fungicides has been the main management practice for Peronospora belbahrii, which is the most important pathogen of sweet basil in the United States. Six replicated experiments were conducted between 2010 and 2016 with field-grown basil of a susceptible cultivar exposed to naturally occurring wind-dispersed sporangiospores of P. belbahrii to evaluate conventional fungicides registered for basil downy mildew in the United States and in development for this use. This project revealed the importance for successful management of using a preventive fungicide application schedule, maintaining a 7-day application interval, and using application equipment designed to provide thorough spray coverage to plants (drop nozzles). Fungicide efficacy was assessed based on incidence of symptomatic leaves rather than disease severity, which is stringent but realistic because there is zero tolerance for disease on fresh-market herbs. Most fungicides were tested as the formulated product marketed in the United States. Oxathiapiprolin was tested as experimental formulations. Its trade name is Orondis. Overall best control was achieved in 2016. Excellent control (99% based on AUDPC values) was obtained with four fungicide programs with oxathiapiprolin, Revus, and ProPhyt, indicating this combination of chemistry was more important than specific timing for each fungicide. Ranman applied in alternation with Revus plus K-Phite was not quite as effective (89% control); this treatment was ineffective in 2015 when the 7-day spray interval was not maintained. Best treatment in 2015 was Quadris applied in alternation with Revus plus oxathiapiprolin for two of three Revus applications. Two different alternations of these fungicides also were effective. But Quadris alternated with Revus was ineffective. When tested singly, the most effective fungicides in 2013 (listed in order based on AUDPC values) were Zampro, Revus, oxathiapiprolin, and Ranman. ProPhyt was effective in 2013 but not in 2012, when another phosphorous acid fungicide, K-Phite, also was ineffective. Only oxathiapiprolin and Zampro were effective in the 2012 experiment; Revus and Ranman were ineffective. Presidio was ineffective both years. Based on the results from this study, Orondis is the most effective fungicide among those evaluated for managing basil downy mildew, and Zampro is second. Neither were labeled for this use on field-grown basil as of June 2020. Ranman applied in alternation with Revus plus K-Phite, a commonly recommended program of labeled fungicides, provided very good control.

A novel formulation technology for baculoviruses protects biopesticide from degradation by ultraviolet radiation

Biopesticides are biological pest control agents that are viewed as safer alternatives to the synthetic chemicals that dominate the global insecticide market. A major constraint on the wider adoption of biopesticides is their susceptibility to the ultraviolet (UV: 290–400 nm) radiation in sunlight, which limits their persistence and efficacy. Here, we describe a novel formulation technology for biopesticides in which the active ingredient (baculovirus) is micro-encapsulated in an ENTOSTAT wax combined with a UV absorbant (titanium dioxide, TiO2). Importantly, this capsule protects the sensitive viral DNA from degrading in sunlight, but dissolves in the alkaline insect gut to release the virus, which then infects and kills the pest. We show, using simulated sunlight, in both laboratory bioassays and trials on cabbage and tomato plants, that this can extend the efficacy of the biopesticide well beyond the few hours of existing virus formulations, potentially increasing the spray interval and/or reducing the need for high application rates. The new formulation has a shelf-life at 30 °C of at least 6 months, which is comparable to standard commercial biopesticides and has no phytotoxic effect on the host plants. Taken together, these findings suggest that the new formulation technology could reduce the costs and increase the efficacy of baculovirus biopesticides, with the potential to make them commercially competitive alternatives to synthetic chemicals.

Cost Benefit Analyses in Managing Late Blight Through Trichoderma asperellum Seed Treatment and Ridomil® Application on Potato

Fungicides overuse in management of late blight has led to increased cost of production and biodiversity issues. To better understand costs and benefits associated with seed treatment to reduce fungicide application, apical cutting and tuber seed crop were pre-treated by either peridermal injection or dipping using T. asperellum suspension at 33%, 66% and 100% concentration and then sprayed separately with Ridomil® (Metalaxyl 4% + Mancozeb 64%) at 21, 14 and 7 (Manufacturer’s Recommended Regime) days interval. Results showed that apical cuttings had 7.5% higher disease severity and 0.2% lower yield than crop from seed tuber. Untreated and 33% T. asperellum were not significant different (p = 0.05) in disease and yield scores. T. asperellum concentration at 66% and 100% reduced disease severity by 26% and 27% resulting to 30% and 29% yield increment respectively. Spray interval of 14 days did not differ significantly from 7 day spray interval in terms of disease score and yield but the regime MRR% was double 7 day spray interval. Maximum yield loss was observed in unprotected plots followed by treatments sprayed at 21 days interval. Combination of 66% and 100% T. asperellum concentration with 14 days interval resulted to higher yield and marginal rate of return compared to any other combination. Seed dipping was four times profitable than injection. The findings suggest that seed treatment at 66% and 100% T. asperellum concentration by dipping in combination with Ridomil® application at 14 days interval significantly reduced late blight epidemics and improved on yield and consequently increased net farm income.

Changes in microbial community and methanogenesis during high-solid anaerobic digestion of ensiled corn stover

Abstract The stability of corn stover high-solid anaerobic digestion is affected by the low efficiency of solid-liquid mass transfer while the total volatile fatty acids accumulation often occurs during the process leading to acidification of the system and influencing the functional anaerobic microbial community of the system. Therefore, the problems of slow start and unstable process often occurred. In this study, the effects of different leachate spraying working conditions on total volatile fatty acids and microbial community structure were studied. Three batch tests of three 45 L leach bed reactors (LBRs) were conducted with continuously domesticated leachate and operated at different process (total solids of 15–30%, spray time of 2–6 min and spray interval of 3–8 h) to determine the relative influence of biotic and abiotic factors on microbial community structure and methanogenesis. Consequently, that within a certain range of parameter setting, biotic effects please an important role than abiotic effects, revealing microbiological mediation of methanogenesis. Higher methane yield of 188.2 mL/g VS was obtained under the conditions of 30%TS, spray time of 4 min in the first two weeks and 2 min in the third week, and spray interval of 6 h. The sludge reacting for two months was used as inoculum. After two months’ cultivation, the seeding sludge became stability and increased activity, and the microbial colony richness and diversity tend to be stable regardless of the operational parameters. This study enriches the understandings of biotic and abiotic factors of microbial community structure and methanogenesis in high-solid anaerobic digestion.

Enhancement of Solar Cell Efficiency by Using TiO2 Nanostructure Doped Fe2O3 Dye and Effect Concentration of Solvent on Optical Properties

Solar energy has the greatest potential of all the sources of renewable energy, as only a small amount of this form of energy could be used, especially when other sources (coal, oil or gas) in the country have depleted. A solar cell is a solid electrical device that converts solar energy directly to electricity. Hybrid solar cells based on inorganic and organic compounds are a promising renewable energy source.
 Aims: The aim of this study was to prepare a nanostructured thin film of titanium oxide: doped iron oxide for enhancement of solar cell efficiency. In addition to studying the effect doped on optical properties of titanium oxide nanostructure thin film.
 Study Design: The spray pyrolysis deposition method used for preparation the nanostructure material.
 Place and Duration of Study: This study was conducted in the department of physics and department of materials sciences, Al-neelain university, between January 2016 and January 2019.
 Methodology: Thin films of Titanium Oxide (TiO2) doped Iron Oxide (Fe2O3) have been prepared by chemical spray pyrolysis deposition technique. A laboratory designed glass atomizer was used for spraying the aqueous solution. Which has an output nozzle about 1mm then the film was deposited on preheated cleaned glass substrates at the temperature of 400ºC. we used different concentration to study optical parameters. A 1.5 g TiO2 powder of anatase structure doped with 1.5 g of Fe2O3 was mixed with 2 ml of ethanol and stirred using a magnetic stirrer for 30 minutes to form TiO2 paste to obtain the starting solution for deposition and spray time was 10 s and spray interval 2 min was kept constant. The carrier gas (filtered compressed air) was maintained at a pressure of 105 Nm-2, and distance between nozzle and substrate was about 30 cm ± 1 cm. The thickness of the sample was measured using the weighting method and was found to be around 400 nm. Optical transmittance and absorbance were records in the wavelength range of (200-1100) nm using UV-Visible spectrophotometer (Shimadzu Company Japan).
 Results: The results obtained showed that the optical band gap decreased from 5.58 eV before doping to (3.9, 3.81, 3.81 and 3.81 eV) after doped for TiO2:Fe2O3 thin films, this result refers to the broadening of secondary levels that product by TiO2: doping to the Fe2O2 thin films. Also, the results showed the variation of refractive index with wavelength for different concentration after doped of TiO2:Fe2O3 films from this figure, it is clear that n decrease with low concentration and increase with high concentration after doped that mean the density is decreased of this films. In addition the extinction coefficient of TiO2:Fe2O3 thin films recorded before doped and with different concentration (1.1, 1.2, 1.5 and 1.6 mol/L) and in the range of (300 – 1200) nm and after doped it observed from that the extinction coefficient, decrease sharply with the increase of wavelength for all prepared films and all the sample after doped is interference between them accept the sample before annealing is far from the other sample.
 Conclusion: Based on the results obtained doping of titanium oxide increases the efficiency of TiO2 thin film in DSSC. It also proves that the fabrication of TiO2 thin films by spray pyrolysis deposition method is successful.

Effect of Annealing Temperature in Improvement the Optical Properties of TiO2 Doped Fe2O3 to Use in Thin Film

Solar energy is already has being widely successfully used in residential and industrial setting for thermal and electrical application such as space technology, communication, etc. I.
 Aims: The aim of this study the effect of the annealing temperature in improvement optical properties of titanium oxide nanostructure doped iron oxide for use in thin film.
 Study Design: The spray pyrolysis deposition method used for preparation the nanostructure material.
 Place and Duration of Study: This study was conducted in department of physics and department of materials sciences, Al-Neelain University, between January 2016 and January 2019. 
 Methodology: Thin films of Titanium Oxide (TiO2) doped Iron Oxide (Fe2O3) have been prepared by chemical spray pyrolysis deposition technique. A laboratory designed glass atomizer was used for spraying the aqueous solution. Which has an output nozzle about 1 mm. then film were deposited on preheated cleaned glass substrates at temperature of 400°C. we used different concentration to study optical parameters. A 1.5 g TiO2 powder of anatase structure doped with 1.5 g of Fe2O3 was mixed with 2 ml of ethanol and stirred using a magnetic stirrer for 30 minutes to form TiO2 paste to obtain the starting solution for deposition and spray time was 10 s and spray interval 2 min was kept constant. The carrier gas (filtered compressed air) was maintained at a pressure of 105 Nm-2, and distance between nozzle and substrate was about 30 cm ± 1 cm. Thickness of sample was measured using the weighting method and was found to be around 400nm. Optical transmittance and absorbance were record in wavelength range of (200-1100) nm using UV-Visible spectrophotometer (Shimadzu Company Japan).
 Results: The results obtained showed that the optical band gap decreased from 5.6eV before annealing to (3.9, 3.26, 3.24 and 3.27 eV) after annealing temperature at(450° – 500°) for TiO2:Fe2O3 thin films, this result refer to the broadening of secondary levels that product by TiO2: doping to the Fe2O2thin films. Also the results showed the variation of refractive index with wavelength for different concentration after annealing temperature at (450° – 500°) of TiO2: Fe2O3 films from this figure, it is clear that n decrease with low concentration and increase with high concentration after annealing temperature that mean the density is decreased of this films. In addition the extinction coefficient of TiO2:Fe2O3 thin films recorded before annealing and with different concentration (1.1, 1.2, 1,5 and 1,6) and in the range of (300 – 1200) nm and at annealing temperature from (450° – 500°). It observed from that the extinction coefficient, decrease sharply with the increase of wavelength for all prepared films and all the sample after annealing is interference between them accept the sample before annealing is far from the other sample.
 Conclusion: The TiO2 thin film shows better result after annealing; By exposing temperature during annealing process degree at (450o- 500o) is found to be the best temperature for annealing TiO2 thin film. The study concluded that an annealing temperature Contributes to the improvement of optical properties related to increasing the efficiency of the solar cell, especially the refractive index, energy gap, extinction coefficient.

Parametric study of a diesel engine fueled with directly injected methanol and pilot diesel

A three-dimensional simulation model is established to investigate a diesel engine fueled with directly injected methanol and pilot diesel. Four parameters (methanol nozzle diameter, methanol injection pressure, and two diesel/methanol spray interval angles: α in the XZ plane and β in the XY plane) are selected to study their effects on combustion characteristics, engine performance, and emissions. The results indicate that methanol nozzle diameter and injection pressure have a great effect on the engine. When the methanol injection duration is kept constant, a larger nozzle diameter paired with a lower injection pressure lead to a lower Pmax, peak HRR, and NOx emissions, but higher soot, THC, and CO emissions. Furthermore, as nozzle diameter increases and injection pressure decreases, fuel economy first improves and then deteriorates. A nozzle diameter of 0.36 mm paired with an injection pressure of 27.4 MPa yield optimal results for both fuel economy and allowable combustion noise. When the direction of methanol spray injected towards the flame is tuned (when α is 2° and β is 15°), better fuel economy and lower pollutant emissions are achieved.

Susceptibility of Cotton Boll Weevil (Coleoptera: Curculionidae) to Spinosyns.

The control of boll weevil, Anthonomus grandis grandis Boh., relies primarily on synthetic insecticides. Although insecticides are registered to spray cotton fields against boll weevils, only a few offer satisfactory control and most have broad-spectrum action. Alternatively, spinosyns have been recommended against lepidopteran pest species in cotton and are considered comparatively of reduced risk to nontargets. The susceptibility of nine populations of boll weevil to spinosad and spinetoram was determined through dried residue on squares and cotton leaves. Furthermore, control efficacy of spinosad and spinetoram compared with the standard organophosphate malathion was determined for caged adults at two different positions within the plant canopy or treated cotton leaves after different spray intervals. Boll weevil susceptibility varied across the nine populations and tested spinosyns. The lethal concentrations (LC50s and LC90s) varied from 8.62 to 32.25 and 49.86 to 281.70 mg a.i./l for spinosad and from 2.17 to 15.36 and 8.58 to 69.36 mg a.i./l for spinetoram. The location of boll weevil within the plant canopy affected the insecticide efficacy with higher mortality when caged on upper parts rather than on lower parts of cotton plants (>85% vs <45% of control) across all three insecticides. In addition, dried residues of spinosyns resulted in adult mortality >80% until the end of the evaluation period (8 d), while the standard malathion caused only 10% at this last evaluation time. Thus, we can conclude that both spinosyns promoted prolonged adult mortality using recommended field rates compared with the standard malathion.

Evaluation of the TOM-CAST Forecasting Model in Asparagus for Management of Stemphylium Leaf Spot in Ontario, Canada

In the last 5 years, asparagus acreage in Canada has increased by over 25%. Stemphylium leaf spot, caused by Stemphylium vesicarium, has emerged as the predominant foliar pathogen of asparagus. Typically, contact fungicides are applied every 14 days; however, regardless of the number of applications, growers are not achieving adequate control of the disease. The TOM-CAST forecasting model is used widely in Michigan asparagus fields, but it has never been assessed for suitability in Ontario or in the popular cultivar, Guelph Millennium. Six field trials were conducted in 2012 and 2013 to evaluate the TOM-CAST forecasting model in two asparagus cultivars. The fungicides chlorothalonil or azoxystrobin/difenoconazole were applied according to the forecasting model or on a 14-day interval. The effectiveness of the forecasting model differed between sites and cultivars. Even though TOM-CAST is used in all cultivars in Michigan, TOM-CAST was not effective on Guelph Millennium. In the cultivar Jersey Giant, however, TOM-CAST with a 20 disease severity value spray interval improved control of Stemphylium leaf spot without increasing the number of sprays, compared with a 14-day treatment. The results in Guelph Millennium differed between sites. At one site, TOM-CAST maintained similar levels of Stemphylium leaf spot, but increased the number of applications, compared with a 14-day application interval. Of more concern, none of the fungicide treatments differed greatly from the untreated control at the other site. Our results show that forecasting models need to be validated locally in asparagus cultivars relevant to production today.

Integrated management of faba bean chocolate spot caused by Botrytis fabae in Gondar, Ethiopia

Integrated management of faba bean chocolate spot (Botrytis fabae Sard.) was studied using moderately tolerant variety, “Hachalu” and the local cultivar at Chilga district during 2016 main cropping season. The objective was to evaluate effect of host resistance, intercropping and fungicide applications on epidemics of faba bean chocolate spot, yield and yield components of faba bean, and sole and intercrop systems productivity. The experiment was randomised complete block design in a factorial combination of two faba bean cultivars, two cropping systems (Hachalu- and local-barley intercropping in 2:1 ratio) and four levels of fungicide (Chlorothalonil) spray and integration in three replications of faba bean and barley, respectively. Cultivars and spray intervals significantly (p < .01) affected the seed yield while cultivars alone had significant variation (p < .01) on 100-seed weight as a main effect. Therefore, 21-days fungicide spray intervals integrated with Hachalu sole and Hachalu-barley intercropping may be considered for chocolate spot management.

Terpene based biopesticides as potential alternatives to synthetic insecticides for control of aphid pests on protected ornamentals

Biopesticides based on plant extracts offer a promising alternative to the use of conventional synthetic pesticides. However, biopesticide products must provide acceptable levels of control. To date, few studies have investigated the efficacy of biopesticide products under conditions that reflect commercial practice. Here we report results from three experiments, one completed under glasshouse conditions in 2014 and two completed under polytunnel conditions, in 2015 and 2016, respectively. These experiments tested the efficacy of three terpene based biopesticides used to control two aphid species, peach-potato aphid (Myzus persicae) and melon and cotton aphid (Aphis gossypii), on ornamental crops. The three biopesticide products tested were orange oil (60 g active ingredient per litre, formulated as a soluble liquid), the essential oil from Chenopodium ambrosioides variety nr. ambrosioides (16.75% active ingredient, formulated as an oil dispersion) and neem oil (1% active ingredient, formulated as emulsifiable concentrate). The biopesticides tested were applied as foliar sprays using a water volume of 600 l/Ha and all experiments were done at Harper Adams University, Shropshire, UK.The biopesticide products tested gave statistically similar levels of control of M. persicae populations on pansy plants as the conventional synthetic insecticide flonicamid (500 g/kg active ingredient, formulated as a wettable granule) and spirotetramat (150 g/l active ingredient, formulated as an oil dispersion). All products reduced numbers of aphids by at least 85% during the experimental period. Orange oil also gave a similar speed of kill to flonicamid and was faster acting than spirotetramat, two conventional synthetic insecticides that are widely used to control aphid pests of ornamental crops. Against A. gossypii on Hebe, orange oil gave similar levels of control (90% reduction in aphid numbers) as flonicamid (98% reduction in aphid numbers), when applied with a spray interval of three days (as per label recommendation). The essential oil from Chenopodium ambrosioides variety nr. ambrosioides was not as effective as flonicamid but did significantly reduced (80% reduction in aphid numbers) numbers of A. gossypii on Hebe compared to a water control when applied with a spray interval of five days. Neem oil was not effective against A. gossypii. Importantly, there was little evidence of any phytotoxicity caused by any of the biopesticide products tested. The potential to use these products as part of an Insecticide Resistance Management (IRM) programme are discussed.

Controlling phytophthora blight of cucumber (Cucumis sativus) in a derived savannah, using different spray intervals of a registered fungicide

Controlling phytophthora blight of cucumber (Cucumis sativus) in a derived savannah, using different spray intervals of a registered fungicide

Temperature Influences on Diapause Induction and Survival in the Boll Weevil (Coleoptera: Curculionidae)

The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), has been the most important pest of cotton (Gossypium spp.) wherever it occurs. Although eradication programs in the United States have reduced the range of this pest, the weevil remains an intractable problem in subtropical Texas, Mexico, and much of South America. A key to managing the weevil in the subtropics and tropics might lie in better understanding its diapause and overwintering survival in regions characterized by relatively high late-season temperatures. We examined the temporal patterns of acquisition of diapause characters at 18.3, 23.9, and 29.4°C, and the effects of temperature during the diapause-induction period on subsequent host-free survival at 23.9°C. Occurrence of the diapause characters generally increased with weevil age at all temperatures but appeared more rapidly at higher temperatures. Acquisition of the diapause characters tended to occur slightly earlier in female weevils compared with the male weevils. Despite the slower development of diapause characters at lower temperatures, when adult weevils were fed under low temperatures, subsequent host-free survival was enhanced. These results are consistent with reports of increased weevil survival with delayed entry into overwintering. Our findings also suggest that the potential host-free survival facilitated by diapause occurring in subtropical or tropical production regions may be reduced compared with dormancy developing in southern temperate regions. This reduced survival potential emphasizes the importance of a maximized host-free season and suggests that the late-season diapause spray intervals should be short enough to ensure that the number of dormant weevils developing in late-season cotton is minimized.

Effects of Powdery Mildew ( Leveillula Taurica and Erysiphe Polygoni ) on Yield and Yield Components of Fenugreek in the Mid-Altitudes of Bale, South Eastern Ethiopia

Fenugreek (Trigonella foenum-graecum L.) is one of the most important seed spice crops in Ethiopia in general and in the mid-altitudes of Bale in particular. Powdery mildew caused by Leveillula taurica and Erysiphe polygoni is a common disease of fenugreek in the mid-altitudes of Bale. To determine the effects of this disease on yield and yield components of the crop, a field experiment was conducted using an improved variety, Hunda’ol, at Goro research site of Sinana Agricultural Research Center, south eastern Ethiopia. Four different spray intervals of a systemic fungicide, Lunar sensation (Fluopyram 250 g/L+ Trifloxystrobin 250 g/L), were used to create different levels of powdery mildew severity. The plots were arranged in Randomized Complete Block Design (RCBD) with three replications. There was severe powdery mildew development on plants in the unsprayed plots. The disease had significant effect on two of the yield parameters, number of seeds per pod and thousand seed weight. It inflicted the total yield loss up to 40%. Hence, application of control measure to minimize this loss is necessary. Resistant varieties are cultural tools that could be used for the management diseases of several crops. However, so far there is no powdery mildew resistant fenugreek variety released in this country. Fungicides can be used to effective control of this disease. The present study revealed that powdery mildew of fenugreek can be controlled by applying lunar sensation twice between 21-days starting from the onset of the disease.

IMPACT OF GARLIC EXTRACT IN COMPARISON WITH CHLOROPYRIFOSE INSECTICIDE AGAINST CERTAIN PESTS AND ASSOCIATED PREDATORS IN COTTON FIELDS AT SHARKIA GOVERNORATE, EGYPT

Field experiments were conducted in cotton fields, Gossypium barbadense L. variety Giza 86 at Zagazig District, Sharkia Governorate, Egypt during 2014 season. Four programs were applied with three respective sprays for each using commercial formulation of garlic extract Nat-108 and varied as spray start times and interval periods towards the development of more environmentally sound technologies for management of cotton aphids (Aphis gossyppii), cotton thrips (Thrips tabaci), sweet potato whitefly (Bemesia tabaci), spider mites (Tetranychus spp.), leafhoppers (Empoasca spp.), green stink bug (Nezara viridula), pink bollworm (Pectinophora gossypiella) and cotton leafworm (Spodoptera littoralis). In addition to the side effects on several predators species found in cotton fields associated with cotton pests, such as, coccinellids, chrysopids, staphylinids, anthocorid, dipterous and true spiders were studied. Results, educed that the commercial formulation of garlic extract at the rate of 1 litter/100 litter water showed relatively high efficiency against aphids, leafhoppers and thrips, with maximum reduction percentages of 81.33, 82.51 and 84.12%, respectively; moderate efficiency against pink bollworm, whitefly, spider mites, green stink bug with maximum reduction percentages of 61.50, 78.89, 67.56 and 54.46%, respectively and low efficacy against predators except at the end season where the relatively highest reduction percentage was 62.91%, while it was less effective against the cotton leaf worm ranged 23.30-25.80% reduction in comparison with 70.56-90.00% reduction in cotton leafworm population for Dursban (chloropyrifose). So, the garlic extract cannot considered as a botanical pesticide against S. littoralis under cotton field conditions at Sharkia Governorate but needs more studies to evaluate its efficacy on different levels of S. littoralis infestation and stags. In regard to the programs results for garlic extract efficacy, it cleared that the first program tended to be the highest sustainable control of aphids, whitefly, thrips and spider mites on cotton plants, where the sprays started just after cotton plants emergence, whereas the numbers of pests were very low while the third program where the sprays started after 20 days of cotton plants emergence was tended to be the highest sustainable control of leafhoppers. In case of N. viridula, it could be decided that the organophosphorous pesticide, Dursban can be used as effective insecticide especially at the end season period. Finally, garlic extract was tended to be safe to predators especially throughout its effective activity period during the period from seedling to the end of growing season of cotton plants that confirmed by the results of the third program which ranged 2.57-21.46% reduction percentages in predators population. So, garlic extract could be recommended to be used effectively against cotton aphids, leafhoppers, cotton thrips and pink bollworm in IPM program of cotton pests in cotton fields. The organophosphorous compound, Dursban can be considered as good control pesticide against tested pests recorded reduction percentages ranged 56.99-96.99% but caused serious damage to associated predators on cotton plants at the end of season period recorded reduction percentages reached to 99.76% that disturbed the natural balance in cotton cultivation area environment.

Effects of Fungicides and Spray Application Interval on Controlling Marssonina Blotch of Apple in the Loess Plateau Region of China.

Marssonina blotch, caused by the fungus Marssonina coronariae, is a serious foliar disease on apple in East Asia as well as in other moist temperate regions in Asia, Europe, and South America. Several fungicides were investigated for their toxicity to mycelial growth and conidial germination of the pathogen in vitro. Tebuconazole, kresoxim-methyl, hexaconazole, propiconazole, and a mixture of tebuconazole and benziothiazolinone sharply inhibited mycelial growth but had less effect on conidial germination. Field tests were conducted in a commercial orchard in Baishui County, Shaanxi Province, China, during 2012, 2013, 2014, and 2015 in order to develop recommendations for apple growers. Three applications of tebuconazole, hexaconazole, propiconazole, or a mixture of tebuconazole and benziothiazolinone at 20-day intervals from early July to late August resulted in defoliation incidence of <5%. When sprays of Bordeaux mixture + tebuconazole, Bordeaux mixture + propiconazole, and Bordeaux mixture + tebuconazole and benziothiazolinone were alternated, the spray interval was extended to 25 days and defoliation incidence remained <5%. Based on historical records and our results, scouting for symptoms should begin in mid-June. We recommend commencing the spray period in early July in years with normal rainfall patterns, and spraying in mid- to late June in years with much rainfall. The findings of this study create a foundation for implementation of an efficient spray program against Marssonina leaf blotch in apple orchards in the Loess Plateau Region of China.

Evaluation of Fungicides and Fungicidal Spray Schedule for the Management of Angular Leaf Spot of Common Bean

Angular Leaf Spot (ALS), caused by Phaeoisariopsisgriseola (Sacc.), is one of the major diseases of common bean in the Southern Ethiopia.The objective of the experiment was to select fungicides and spray intervals to recommend low cost management options for the control of ALS disease. The experiment was carried out under natural epidemic at Awassa Agricultural Research Center in Southern Ethiopia during 2013 -2014. The study consisted of five different fungicides (Ridomil Gold, Penncozeb, Curzate, Tilt 250 EC and Bumper 25 EC) in combination with two spray intervals ( 7 and 14 days) using two common bean varieties (HawassaDume and Red Wolaita) having dissimilar levels of reaction to ALS. The treatments were laid using Randomized Complete Block Design (RCBD) in factorial arrangement. All fungicides tested were found to be effective in controlling the ALS disease as compared to unsprayed treatment. Ridomil Gold was the most effective fungicide in reducing the disease severity and yield loss,followed by Curzate and Penncozeb, where asPropiconazole fungicides (Tilt 250 and Bumper) showed high AUDPC value as compared to the other fungicides. Ridomil Gold reduced the AUDPC value by 75% and 40% on susceptible and moderately resistant varieties, respectively. Grain yield loss was estimated to be 35 to 40 % and 74 to 85 % in moderately resistant and susceptible variety, respectively. There was not significance difference (p

Knowledge, Attitudes, and Practices of Tomato Producers and Vendors in Uganda

Background: Uganda’s horticultural sub-sector is growing at a fast rate and tomato is one of the major horticultural crops with wide spread production in peri-urban and rural areas. However tomato is susceptible to different pests and diseases and this has resulted into use of synthetic pesticides as the main control strategy. There is wide spread pesticide misuse behavior amongst tomato farmers owing to different social, economical and regulatory factors. This misuse includes among others inadequate personal protection and failure to follow the recommended pre-harvest no spray interval. This puts the health of millions of tomato farmers and consumers at risk. In Uganda, information on such misuse, consumer safety, and residues in food is limited. Objectives: This article presents findings from a survey of knowledge, attitudes and practices of tomato farmers and vendors. The article also draws conclusions from the findings and recommends areas that could help to improve or avert the foregoing. Methodology: This study was carried out in Nangabo Sub-County, Kyadondo County, Wakiso District in the Central Region of Uganda. Quantitative and qualitative data was gathered using an interviewer administered structured questionnaire and Focus Group Discussion guides, respectively from 50 tomato farmers and 6 tomato vendors in June 2013. Quantitative data analysis was done using the Epi Info statistical package software, while the qualitative data were audio recorded, transcribed and analysed on the basis of the themes/objectives of the study, namely, pesticide use and handling knowledge, attitudes and practices by farmers and vendors. Results: 41.4 years was the average age of farmer respondents. 26% were females. 56% had completed secondary education. 92% spray with synthetic pesticides as their main control tactic against pests and diseases. 44% reported spraying three times in a week during the wet season. 24.5% were not aware of any health risks of spraying tomatoes close to harvest time. 45.8% reported spraying their tomatoes less than a week to harvest time while 29.2% of the respondents sprayed their tomatoes at/after harvest; with reason for this spraying being to extend the shelf-life ( according to 70% of respondents), to attract customers (50%) and to control pests and diseases (46%). Class II pesticide, especially organophosphates were the most used. Conclusion: Recommended pesticide usage is not followed. Inadequate personal protection and use of pesticides for wrong purposes are prevalent misuse behavior. Market demand, lack of knowledge, financial constraints and community beliefs influence pesticide use behavior. Shelf life and tomato appearance are the key drivers of nonobservance of the pre-harvest no spray period. Education influences farmers’ safe use but doesn’t guarantee producer concern towards the consumer. Money takes precedence compared to health, amongst these tomato farmers.

Knowledge, Attitudes, and Practices of Tomato Producers and Vendors in Uganda

Background: Uganda’s horticultural sub-sector is growing at a fast rate and tomato is one of the major horticultural crops with wide spread production in peri-urban and rural areas. However tomato is susceptible to different pests and diseases and this has resulted into use of synthetic pesticides as the main control strategy. There is wide spread pesticide misuse behavior amongst tomato farmers owing to different social, economical and regulatory factors. This misuse includes among others inadequate personal protection and failure to follow the recommended pre-harvest no spray interval. This puts the health of millions of tomato farmers and consumers at risk. In Uganda, information on such misuse, consumer safety, and residues in food is limited. Objectives: This article presents findings from a survey of knowledge, attitudes and practices of tomato farmers and vendors. The article also draws conclusions from the findings and recommends areas that could help to improve or avert the foregoing. Methodology: This study was carried out in Nangabo Sub-County, Kyadondo County, Wakiso District in the Central Region of Uganda. Quantitative and qualitative data was gathered using an interviewer administered structured questionnaire and Focus Group Discussion guides, respectively from 50 tomato farmers and 6 tomato vendors in June 2013. Quantitative data analysis was done using the Epi Info statistical package software, while the qualitative data were audio recorded, transcribed and analysed on the basis of the themes/objectives of the study, namely, pesticide use and handling knowledge, attitudes and practices by farmers and vendors. Results: 41.4 years was the average age of farmer respondents. 26% were females. 56% had completed secondary education. 92% spray with synthetic pesticides as their main control tactic against pests and diseases. 44% reported spraying three times in a week during the wet season. 24.5% were not aware of any health risks of spraying tomatoes close to harvest time. 45.8% reported spraying their tomatoes less than a week to harvest time while 29.2% of the respondents sprayed their tomatoes at/after harvest; with reason for this spraying being to extend the shelf-life ( according to 70% of respondents), to attract customers (50%) and to control pests and diseases (46%). Class II pesticide, especially organophosphates were the most used. Conclusion: Recommended pesticide usage is not followed. Inadequate personal protection and use of pesticides for wrong purposes are prevalent misuse behavior. Market demand, lack of knowledge, financial constraints and community beliefs influence pesticide use behavior. Shelf life and tomato appearance are the key drivers of nonobservance of the pre-harvest no spray period. Education influences farmers’ safe use but doesn’t guarantee producer concern towards the consumer. Money takes precedence compared to health, amongst these tomato farmers.