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The impact of two drying methods on the quality of high-moisture rice: Poster
Get PDFIn this experiment, freshly harvested rice was dried by natural and mechanical methods. For natural drying, paddy rice was spread on a cement floor under a shelter at a thickness of 4cm, and it was turned twice a day. At a temperature of 19.3°C and a relative humidity of 58.8%, a total of 28 days was needed to reduce the water content from 23.11 to 14.38%. For mechanical drying, the Guwang 5HXG-15B circulating dryer was used, drying temperature was set to 42°C, and it took a total of 5 hours to reduce the water content from 23.1 to 11.8%. The changes in spore count, fatty acid value, germination rate, waist burst rate, whole polished rice rate, and taste value of rice mold after drying were studied. The results showed that compared with mechanical drying, the drying rate of air-dried rice was slower, and the number of mold spores increased from 0.65×105/g to 3.05×105/g, a 3.7 times increase. The number of mold spores in dried rice was not significant. Dried rice fatty acid value of 25.1mg/100g for natural drying was higher than the value of 19.9mg/100g for mechanical drying. High temperature affected rice seed vigor: mechanically dried rice germination rate was 58.0%, far lower than the 87.5% for natural drying. The blasting rate, polished rice rate, and taste value of mechanically dried rice were 5.33%, 57.9%, and 83.7, respectively, which was 2.33%, 58.9%, and 89.3 for naturally-dried rice. The processing quality and taste quality were even worse. Therefore, the drying process of the optimized circulation dryer should be further adjusted to reduce its impact on rice processing quality and taste quality.In this experiment, freshly harvested rice was dried by natural and mechanical methods. For natural drying, paddy rice was spread on a cement floor under a shelter at a thickness of 4cm, and it was turned twice a day. At a temperature of 19.3°C and a relative humidity of 58.8%, a total of 28 days was needed to reduce the water content from 23.11 to 14.38%. For mechanical drying, the Guwang 5HXG-15B circulating dryer was used, drying temperature was set to 42°C, and it took a total of 5 hours to reduce the water content from 23.1 to 11.8%. The changes in spore count, fatty acid value, germination rate, waist burst rate, whole polished rice rate, and taste value of rice mold after drying were studied. The results showed that compared with mechanical drying, the drying rate of air-dried rice was slower, and the number of mold spores increased from 0.65×105/g to 3.05×105/g, a 3.7 times increase. The number of mold spores in dried rice was not significant. Dried rice fatty acid value of 25.1mg/100g for natural drying was higher than the value of 19.9mg/100g for mechanical drying. High temperature affected rice seed vigor: mechanically dried rice germination rate was 58.0%, far lower than the 87.5% for natural drying. The blasting rate, polished rice rate, and taste value of mechanically dried rice were 5.33%, 57.9%, and 83.7, respectively, which was 2.33%, 58.9%, and 89.3 for naturally-dried rice. The processing quality and taste quality were even worse. Therefore, the drying process of the optimized circulation dryer should be further adjusted to reduce its impact on rice processing quality and taste quality
High quality genomic resources for stored product insects: Presentation
No full textThe expansion of genomic resources for stored product insects has largely been hampered by cost, time required for inbreeding, and technical issues that can arise during genome assembly from pooling multiple individuals together for DNA isolation and library preparation. However, newer library methods, such as 10X Chromium libraries, largely overcome these issues in that sufficient DNA can be recovered from a single individual for library prep and allelic variants are assembled as separate phase blocks, eliminating the need for inbreeding. Using 10X Chromium libraries coupled with 150 x 150 bp HiSeqX sequencing to a depth of at least 60X coverage, we are developing high quality draft genome assemblies for eight different stored product insect species, including Dermestidae (Trogoderma variabile, Trogoderma granarium, and Dermestes maculatus), Tenebrionidae (Tribolium confusum), Anobiidae (Lasioderma serricorne and Stegobium paniceum), Bostrichidae (Prostephanus truncatus), and Pyralidae (Plodia interpunctella). Overall, BUSCO (Benchmarking Using Single Copy Orthologs) scores exceeded 95% in all assemblies with few fragmented or duplicated genes, suggesting a high quality assembly of the gene space. Further, scaffold N50s exceeded 1 Mb in many cases and further improvements to these scaffolding metrics will be made using linkage maps and Hi-C libraries. Overall, this approach will yield high quality assemblies for eight different insects and could be used to quickly and efficiently generate draft assemblies of invasive or emerging stored product pests.The expansion of genomic resources for stored product insects has largely been hampered by cost, time required for inbreeding, and technical issues that can arise during genome assembly from pooling multiple individuals together for DNA isolation and library preparation. However, newer library methods, such as 10X Chromium libraries, largely overcome these issues in that sufficient DNA can be recovered from a single individual for library prep and allelic variants are assembled as separate phase blocks, eliminating the need for inbreeding. Using 10X Chromium libraries coupled with 150 x 150 bp HiSeqX sequencing to a depth of at least 60X coverage, we are developing high quality draft genome assemblies for eight different stored product insect species, including Dermestidae (Trogoderma variabile, Trogoderma granarium, and Dermestes maculatus), Tenebrionidae (Tribolium confusum), Anobiidae (Lasioderma serricorne and Stegobium paniceum), Bostrichidae (Prostephanus truncatus), and Pyralidae (Plodia interpunctella). Overall, BUSCO (Benchmarking Using Single Copy Orthologs) scores exceeded 95% in all assemblies with few fragmented or duplicated genes, suggesting a high quality assembly of the gene space. Further, scaffold N50s exceeded 1 Mb in many cases and further improvements to these scaffolding metrics will be made using linkage maps and Hi-C libraries. Overall, this approach will yield high quality assemblies for eight different insects and could be used to quickly and efficiently generate draft assemblies of invasive or emerging stored product pests
Green ecological grain storage technology and quality control in China: Presentation
No full textGreen ecological grain storage technologies (GEGSTs) are the means of controlling stored grain quality, and quality changes of stored grain are the basis of GEGSTs control. This paper introduces that GEGSTs are widely used in China, including monitoring and early warning of stored grain pest and mould, pest control by using food-grade materials, controlled atmosphere for pest control, ventilation for lowering and equalizing temperature, low and quasi-low temperature grain storage, treatment of hot spots, etc. And it introduces that grain processing enterprises’ and market’s request for grain quality, is called “quality control”. It also clarifies that stored grain quality control is the purpose, and emphasizes that GEGSTs control is the process, so GEGSTs control should serve for quality control. Therefore, we propose that the technology application and the quality control of grain storage are equally important, and without the quality control, the technology application could be invalid, especially for sensitive areas in grain bulks. In the process of grain storage, special attention should be paid to quality changes in the sensitive areas, like real-time monitoring. Identify and utilize scientific and reasonable technology accordingly, including related technologies and equipment, to improve "overall" quality control level of stored grain bulks, and to gradually standardize them. By means of GEGSTs, positive ecological storage conditions are effectively utilized, which helps us achieve the purposes of safety, no pollution, high quality and nutrition during grain storage.Green ecological grain storage technologies (GEGSTs) are the means of controlling stored grain quality, and quality changes of stored grain are the basis of GEGSTs control. This paper introduces that GEGSTs are widely used in China, including monitoring and early warning of stored grain pest and mould, pest control by using food-grade materials, controlled atmosphere for pest control, ventilation for lowering and equalizing temperature, low and quasi-low temperature grain storage, treatment of hot spots, etc. And it introduces that grain processing enterprises’ and market’s request for grain quality, is called “quality control”. It also clarifies that stored grain quality control is the purpose, and emphasizes that GEGSTs control is the process, so GEGSTs control should serve for quality control. Therefore, we propose that the technology application and the quality control of grain storage are equally important, and without the quality control, the technology application could be invalid, especially for sensitive areas in grain bulks. In the process of grain storage, special attention should be paid to quality changes in the sensitive areas, like real-time monitoring. Identify and utilize scientific and reasonable technology accordingly, including related technologies and equipment, to improve "overall" quality control level of stored grain bulks, and to gradually standardize them. By means of GEGSTs, positive ecological storage conditions are effectively utilized, which helps us achieve the purposes of safety, no pollution, high quality and nutrition during grain storage
Host-age preference of Theocolax elegans (Westwood) (Hymenoptera: Pteromalidae), a larval parasitoid of the lesser grain borer, Rhyzopertha dominica (Fabricius) (Coleoptera: Bostrichidae) and the cowpea weevil, Callosobruchus maculatus: Presentation
Get PDFThe pteromalids (Hymenoptera: Pteromalidae) Anisopteromalus calandrae (Howard), Dinarmus basalis (Rondani), Lariophagus distinguendus (Förster), Pteromalus cerealellae (Ashmead) and Theocolax elegans (Westwood) are solitary larval ectoparasitoids used to suppress several species of stored-product insects that infest storage grains. We investigated host-age preference of T. elegans using no-choice laboratory experiments. Lesser grain borer, Rhyzopertha dominica (Fabricius) (Coleoptera: Bostrichidae) larvae (9, 11, 13, 15, 17, 19, 21 and 23 days-old) in wheat grain kernel and cowpea weevil, Callosobruchus maculatus (Fabricius) (Coleoptera: Chrysomelidae) larvae (5–19 days-old) in cowpea beans were exposed to neonate T. elegans mated females to lay their eggs for two days. Our results showed that the highest number of parasitoids emerged from 23 days-old R. dominica larvae. The numbers of parasitoids emerged from 19, 21 and 23 days-old R. dominica larvae were statistically significantly different in experiments (F-test, 0.05). Progeny of T. elegans reared from R. dominica and C. maculatus larvae were either fully-winged (macropterous), short-winged (brachypterous) or wingless (apterous). Female T. elegans were rarely host-feeding on C. maculatus larvae. Theocolax elegans progeny were emerging from 14 days-old C. maculatus larvae only. We discussed insectary mass production of T. elegans for biological control.The pteromalids (Hymenoptera: Pteromalidae) Anisopteromalus calandrae (Howard), Dinarmus basalis (Rondani), Lariophagus distinguendus (Förster), Pteromalus cerealellae (Ashmead) and Theocolax elegans (Westwood) are solitary larval ectoparasitoids used to suppress several species of stored-product insects that infest storage grains. We investigated host-age preference of T. elegans using no-choice laboratory experiments. Lesser grain borer, Rhyzopertha dominica (Fabricius) (Coleoptera: Bostrichidae) larvae (9, 11, 13, 15, 17, 19, 21 and 23 days-old) in wheat grain kernel and cowpea weevil, Callosobruchus maculatus (Fabricius) (Coleoptera: Chrysomelidae) larvae (5–19 days-old) in cowpea beans were exposed to neonate T. elegans mated females to lay their eggs for two days. Our results showed that the highest number of parasitoids emerged from 23 days-old R. dominica larvae. The numbers of parasitoids emerged from 19, 21 and 23 days-old R. dominica larvae were statistically significantly different in experiments (F-test, 0.05). Progeny of T. elegans reared from R. dominica and C. maculatus larvae were either fully-winged (macropterous), short-winged (brachypterous) or wingless (apterous). Female T. elegans were rarely host-feeding on C. maculatus larvae. Theocolax elegans progeny were emerging from 14 days-old C. maculatus larvae only. We discussed insectary mass production of T. elegans for biological control
Radio frequency heat treatment for controlling cigarette beetle in dried tobacco: Poster
Get PDFTobacco (Nicotiana tabacum L.) is one of many agricultural commodities produced in Thailand. There are Virginia (flue-cured tobacco) and Burley (air-cured tobacco) typesand Cigarette beetle, Lasioderma sericorne F. is the most important insect pest that attacks dried tobacco. The efficacy of radio frequency (RF) heat treatment at 27.12 MHz was examined to control cigarette beetle on dried tobacco. Various growth stages of cigarette beetle were prepared within samples of dried tobacco and were exposed to RF at 55, 60, and 65 °C for 1, 2 and 3 minutes. The results showed that pupal and adult stages of cigarette beetle were the most tolerant stages to RF heat treatments. The RF treatment at 65 °C for 3 minutes is able to cause complete mortality of egg, larval, pupal and adult stages of cigarette beetle4.Tobacco (Nicotiana tabacum L.) is one of many agricultural commodities produced in Thailand. There are Virginia (flue-cured tobacco) and Burley (air-cured tobacco) typesand Cigarette beetle, Lasioderma sericorne F. is the most important insect pest that attacks dried tobacco. The efficacy of radio frequency (RF) heat treatment at 27.12 MHz was examined to control cigarette beetle on dried tobacco. Various growth stages of cigarette beetle were prepared within samples of dried tobacco and were exposed to RF at 55, 60, and 65 °C for 1, 2 and 3 minutes. The results showed that pupal and adult stages of cigarette beetle were the most tolerant stages to RF heat treatments. The RF treatment at 65 °C for 3 minutes is able to cause complete mortality of egg, larval, pupal and adult stages of cigarette beetle4
A preliminary study of growth and development of Cheyletus malaccensis (Oudemans) under different humidity conditions: Poster
Get PDFCheyletus malaccensis (Oudemans) is a species of predatory mite, which is widely distributed in grain storage, and is a potential natural enemy of stored-product pests. Based on the typical temperatures and humidities that occur in granaries, the growth and development of C. malaccensis was studied at 24°C with different relative humidities (RH 65±2%, 75±2%, 85±2% and 95±2%). During this study, C. malaccensis was fed on Acarus siro (Linnaeus), a very important stored grain pest to investigate its potential to control this pest and production of this natural enemy in the laboratory. The results showed that C. malaccensis has five developmental stages, egg, larva, protonymph, deutonymph and adult. The deutonymph stage is absent in males. For females, the developmental time from egg to adult was shortest at 85±2 % RH and averaged 16.3 days; developmental time was longest at 65±2 % RH and averaged 18.6 days. The male mites in the 95±2% RH trials had the shortest developmental time which averaged 12.6 days; it was longest at 65±2% RH where it averaged 14.7 days. At 95±2% RH, the male adult lived 83.5 d and its longevity from egg to adult was 95.8 d. Humidity had a significant effect on how long the adults lived and the duration of all developmental stages. At 85±2 % RH, the maximum average number of eggs per female, oviposition period and daily fecundity were 493.0, 46.2 d, and 10.3, respectively. This study provides basic biological parameters for C. malaccensis, a potential biological control agent for mite pests infesting stored grain.Cheyletus malaccensis (Oudemans) is a species of predatory mite, which is widely distributed in grain storage, and is a potential natural enemy of stored-product pests. Based on the typical temperatures and humidities that occur in granaries, the growth and development of C. malaccensis was studied at 24°C with different relative humidities (RH 65±2%, 75±2%, 85±2% and 95±2%). During this study, C. malaccensis was fed on Acarus siro (Linnaeus), a very important stored grain pest to investigate its potential to control this pest and production of this natural enemy in the laboratory. The results showed that C. malaccensis has five developmental stages, egg, larva, protonymph, deutonymph and adult. The deutonymph stage is absent in males. For females, the developmental time from egg to adult was shortest at 85±2 % RH and averaged 16.3 days; developmental time was longest at 65±2 % RH and averaged 18.6 days. The male mites in the 95±2% RH trials had the shortest developmental time which averaged 12.6 days; it was longest at 65±2% RH where it averaged 14.7 days. At 95±2% RH, the male adult lived 83.5 d and its longevity from egg to adult was 95.8 d. Humidity had a significant effect on how long the adults lived and the duration of all developmental stages. At 85±2 % RH, the maximum average number of eggs per female, oviposition period and daily fecundity were 493.0, 46.2 d, and 10.3, respectively. This study provides basic biological parameters for C. malaccensis, a potential biological control agent for mite pests infesting stored grain
Postharvest treatment research at USDA-ARS: stored product fumigation: Presentation
No full textThe overall goal of this USDA-ARS research is to ensure the protection and quality of stored product foodstuffs. The results of this research directly enhance production, distribution, and safety of foodstuffs, promote and retain access of United States-grown crops to domestic and foreign markets, and protect the United States and trading partners from the agricultural, ecological and economic threat posed by quarantine and invasive pests. In general, USDA-ARS research related to the fumigation of stored products focuses on the development of techniques to rapidly disinfest raw products of field pests, control pests in processed products amenable to reinfestation and microbial infection, and reduce reliance on fumigation as a stand-alone measure for postharvest disinfestations and disinfections. Specific research objectives include: comparative evaluation of alternative fumigants to methyl bromide in postharvest applications, development of novel technologies to reduce and eliminate atmospheric emissions from chambers used in postharvest fumigation, and design production strategies that allow for a more strategic postharvest use of methyl bromide and alternative fumigants. Recent research findings will be presented and discussed, including: exposure requirements of phosphine on key stored product pests (as related to resistance management), the establishment of efficacy and experimental criterion for quarantine applications, and the development of models to quantitatively understand the underpinnings of fumigations and related phytosanitary treatments.The overall goal of this USDA-ARS research is to ensure the protection and quality of stored product foodstuffs. The results of this research directly enhance production, distribution, and safety of foodstuffs, promote and retain access of United States-grown crops to domestic and foreign markets, and protect the United States and trading partners from the agricultural, ecological and economic threat posed by quarantine and invasive pests. In general, USDA-ARS research related to the fumigation of stored products focuses on the development of techniques to rapidly disinfest raw products of field pests, control pests in processed products amenable to reinfestation and microbial infection, and reduce reliance on fumigation as a stand-alone measure for postharvest disinfestations and disinfections. Specific research objectives include: comparative evaluation of alternative fumigants to methyl bromide in postharvest applications, development of novel technologies to reduce and eliminate atmospheric emissions from chambers used in postharvest fumigation, and design production strategies that allow for a more strategic postharvest use of methyl bromide and alternative fumigants. Recent research findings will be presented and discussed, including: exposure requirements of phosphine on key stored product pests (as related to resistance management), the establishment of efficacy and experimental criterion for quarantine applications, and the development of models to quantitatively understand the underpinnings of fumigations and related phytosanitary treatments
Three and half decades of research on controlled atmosphere storage of grains under nitrogen and recent utilization of the technology in Nigeria: Presentation
Get PDFA major breakthrough of Nigerian Stored Products Research Institute (NSPRI) is in the development of Inert Atmosphere Metal Silo (IAMS) in bulk grain storage for suitability of the climate, adoption and utilization in Nigeria. This technology uses nitrogen gas to achieve a controlled atmosphere (N2-CA) or environment for the control of stored products pests infestation and damage. Achieved 100% mortality of all life adults and immature stages of stored products insect pests; inhibited mould growth, maintained biochemical composition of stored grain and germinability (85% -91%) recorded at 12 months of storage. The system has been used to effectively store white maize, groundnut, Ife brown cowpea, wheat, paddy rice and yellow sorghum for periods of 12 – 48 months. The only system that has ability to store cowpea which cannot be stored in conventional silos. Research activities commenced from laboratory trials to pilot scale and later to medium and commercial levels. Shading the IAMS top against direct sun effect with palm fronds or hood for insulation prevented moisture migration and condensation, and maintained temperature below 30 oC in stored grain. A return per unit on investment of 0.44 was recorded when utilized for storage of wheat for a period of 48 months. IAMS has economic advantages over conventional silos which require frequency of pesticides application, turning of grains to prevent caking, food poisoning and high cost of labour. The recent utilization of this technology is due to increased awareness and demands for availability of grains for food safety, quality and nutrition. IAMS is being taken up by some entrepreneurs, marketers and Landmark University, Omu-Aru, Kwara state for grain storage in Nigeria. This technology is available for use at smallholder, medium, commercial and strategic grain reserve levels. Three and half decades of application of IAMS technology in grain storage in Nigeria is discussed.A major breakthrough of Nigerian Stored Products Research Institute (NSPRI) is in the development of Inert Atmosphere Metal Silo (IAMS) in bulk grain storage for suitability of the climate, adoption and utilization in Nigeria. This technology uses nitrogen gas to achieve a controlled atmosphere (N2-CA) or environment for the control of stored products pests infestation and damage. Achieved 100% mortality of all life adults and immature stages of stored products insect pests; inhibited mould growth, maintained biochemical composition of stored grain and germinability (85% -91%) recorded at 12 months of storage. The system has been used to effectively store white maize, groundnut, Ife brown cowpea, wheat, paddy rice and yellow sorghum for periods of 12 – 48 months. The only system that has ability to store cowpea which cannot be stored in conventional silos. Research activities commenced from laboratory trials to pilot scale and later to medium and commercial levels. Shading the IAMS top against direct sun effect with palm fronds or hood for insulation prevented moisture migration and condensation, and maintained temperature below 30 oC in stored grain. A return per unit on investment of 0.44 was recorded when utilized for storage of wheat for a period of 48 months. IAMS has economic advantages over conventional silos which require frequency of pesticides application, turning of grains to prevent caking, food poisoning and high cost of labour. The recent utilization of this technology is due to increased awareness and demands for availability of grains for food safety, quality and nutrition. IAMS is being taken up by some entrepreneurs, marketers and Landmark University, Omu-Aru, Kwara state for grain storage in Nigeria. This technology is available for use at smallholder, medium, commercial and strategic grain reserve levels. Three and half decades of application of IAMS technology in grain storage in Nigeria is discussed
Update on ProFume® gas fumigant (sulfuryl fluoride) use for post-harvest pest control: Presentation
Get PDFEstablishing the value of modern seed storage methods for wheat in diverse production ecologies in Nepal: Poster
Get PDFIn the developing-country context of Nepal, farmers often incur in seed losses of 15-30% due to improper storage. To evaluate the efficacy and costs of modern storage alternatives, experimental trials were set up among ten farmers each in two contrasting ecologies, i.e. Palpa (hills) and Rupandehi (terai plains) districts of Nepal in 2013. Several wheat seed storage options were contrasted including farmer practices (FP) such as reused fertilizer bags, polythene bags, household metal containers, and mud bins. Modern storage methods that were evaluated included plastic bags (with and without pesticide), metal bins, and hermetic ‘SuperGrainbag’ (SGB). Seed quality and losses were assessed after six months of storage (May-October) with parameters such as grain moisture content, insect damage, seed germination, and seedling vigor. The overall quality of seed with FPs was lower in the hills than in the terai plains. Among the treatments, SGBs were more effective in maintaining acceptable seed moisture levels, controlling insect damage (<1%), preserving germination (>90% lab, >65% field), and promoting seedling vigor. Metal bins and plastic bags without pesticide had higher insect damage (7- 15%) compared to FP and plastic bags with pesticide (2-5%). In terms of storage costs, SGBs were comparable with the farmers’ storage methods (5-6 per 100 kg seed storage). Our findings demonstrate that SGBs are better at maintaining seed quality and more economical than not only FP but also the other modern storage methods evaluated in this study across different production ecological regions in Nepal