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Germination rates of frozen grain legume seeds in Cameroon: Poster
No full textA project on collection and conservation of genetic resources was carried out in Cameroon in 2014 in villages around Yaounde, Mbalmayo, and Ebolowa. Samples of all grain legume species cultivated by the farmers were collected from the 15th of March till early May 2015. Farmers in these zones cultivate mostly ground nuts, followed by soybean and cowpea. A total of 39, 13, and 45 samples were collected from Yaounde, Mbalmayo, and Ebolowa, respectively. After collection, samples were sun-dried, treated, labeled, plasticized, and stored in the freezer at -20oC in the Institute of Agricultural Research for Development (IRAD) store room at Nkolbisson, Yaounde. A trial was carried out at IRAD Kumba experimental farms in 2016 to purify and maintain 14 cowpea and 12 groundnut samples from the freezer, under the C2D project. There were highly significant differences (P< 0.05) amongst samples (treatments) for the germination rate. Cowpea samples had a germination rate ranging from 0.33 to 47.67%, while germination rates for groundnuts were between16.67 to 68.33%. Out of the 26 samples, only 5 (19%) had germination rates above 50%. Due to irregular power supply, freezing turned out to be an ineffective storage method for grain legume seeds. Seeds are now being maintained in vivo in small quantities and on seasonal basis which renders the job of plants breeders very difficult and ineffective. Alternatives storage methods and facilities for grains and seeds in developing countries like Cameroon remain an urgent need to boost research and ensure food security.A project on collection and conservation of genetic resources was carried out in Cameroon in 2014 in villages around Yaounde, Mbalmayo, and Ebolowa. Samples of all grain legume species cultivated by the farmers were collected from the 15th of March till early May 2015. Farmers in these zones cultivate mostly ground nuts, followed by soybean and cowpea. A total of 39, 13, and 45 samples were collected from Yaounde, Mbalmayo, and Ebolowa, respectively. After collection, samples were sun-dried, treated, labeled, plasticized, and stored in the freezer at -20oC in the Institute of Agricultural Research for Development (IRAD) store room at Nkolbisson, Yaounde. A trial was carried out at IRAD Kumba experimental farms in 2016 to purify and maintain 14 cowpea and 12 groundnut samples from the freezer, under the C2D project. There were highly significant differences (P< 0.05) amongst samples (treatments) for the germination rate. Cowpea samples had a germination rate ranging from 0.33 to 47.67%, while germination rates for groundnuts were between16.67 to 68.33%. Out of the 26 samples, only 5 (19%) had germination rates above 50%. Due to irregular power supply, freezing turned out to be an ineffective storage method for grain legume seeds. Seeds are now being maintained in vivo in small quantities and on seasonal basis which renders the job of plants breeders very difficult and ineffective. Alternatives storage methods and facilities for grains and seeds in developing countries like Cameroon remain an urgent need to boost research and ensure food security
Innovative stored plant products in Germany and the potential threat by native and invasive pest insects: Presentation
Get PDFClimate change, economic-political developments as well as new trends in diet and in bio-economy considerably influence the assortment of cultivated plants in Germany and thereby, determine the plant products which have to be stored after harvest. In the light of the International Year of Pulses 2016 and also, as a result of the European Soya Declaration, the acreage cultivated with new plants such as pulses, stress tolerant wheat varieties and also oil seed rape expanded worldwide. Due to increasing stocks of novel commodities, the emergence of economically important insects infesting stored products and the possible risk caused by native and invasive pest species have to be generally considered during storage. In this overall context, we studied the capacity of various stored-product pest insects to infest two important pulses. In laboratory tests different varieties of soy and lupine have been offered as whole seeds, grist and flour to selected moth and beetle species common in Germany. Over 14 weeks we examined the developmental time from egg to eclosion as well as the number of adults in the F1 generation compared to control insects reared on their standard feeding substrate. First findings under laboratory conditions (20-25 °C, 65-70 % RH) indicate that these innovative stored products, and in particular its simply processed plant products are highly susceptible to moths (i.a. Ephestia elutella, Plodia interpunctella) and to a much lesser extent also to some beetle species (i.a. Callosobruchus chinensis, Tribolium confusum), but the usally recommended optimal storage conditions (T = 16 °C, RH = 65%) can prevent a loss of volume and quality.Climate change, economic-political developments as well as new trends in diet and in bio-economy considerably influence the assortment of cultivated plants in Germany and thereby, determine the plant products which have to be stored after harvest. In the light of the International Year of Pulses 2016 and also, as a result of the European Soya Declaration, the acreage cultivated with new plants such as pulses, stress tolerant wheat varieties and also oil seed rape expanded worldwide. Due to increasing stocks of novel commodities, the emergence of economically important insects infesting stored products and the possible risk caused by native and invasive pest species have to be generally considered during storage. In this overall context, we studied the capacity of various stored-product pest insects to infest two important pulses. In laboratory tests different varieties of soy and lupine have been offered as whole seeds, grist and flour to selected moth and beetle species common in Germany. Over 14 weeks we examined the developmental time from egg to eclosion as well as the number of adults in the F1 generation compared to control insects reared on their standard feeding substrate. First findings under laboratory conditions (20-25 °C, 65-70 % RH) indicate that these innovative stored products, and in particular its simply processed plant products are highly susceptible to moths (i.a. Ephestia elutella, Plodia interpunctella) and to a much lesser extent also to some beetle species (i.a. Callosobruchus chinensis, Tribolium confusum), but the usally recommended optimal storage conditions (T = 16 °C, RH = 65%) can prevent a loss of volume and quality
The orientation of Tribolium castaneum adults in the presence of aggregation pheromone 4,8-Dimethyldecanal and food oils
Get PDFMonitoring of Tribolium castaneum, the red flour beetle, involves the use of aggregation pheromone 4,8- dimethyldecanal (4,8 DMD) and kairomones such as cereal oils. Despite their present use, certain information which maximizes the efficacy of these compounds is still lacking. These experiments tested the effects of distance from the pheromone and edible oils on the orientation of T. castaneum adults. The movement of adults toward the aggregation pheromone was determined by changing the distance from the pheromone or the air flow. The adults released inside a glass apparatus tested their orientation either toward the food oils or the empty vial. The maximum trap catch was recorded at distances up to 60 cm from the pheromone and with the presence of air flow. The oils having botanical origin successfully attracted adults than those of animal origin. It is concluded that the orientation of T. castaneum adults varies with the distance from pheromone, air flow and the nature of food oil.Monitoring of Tribolium castaneum, the red flour beetle, involves the use of aggregation pheromone 4,8- dimethyldecanal (4,8 DMD) and kairomones such as cereal oils. Despite their present use, certain information which maximizes the efficacy of these compounds is still lacking. These experiments tested the effects of distance from the pheromone and edible oils on the orientation of T. castaneum adults. The movement of adults toward the aggregation pheromone was determined by changing the distance from the pheromone or the air flow. The adults released inside a glass apparatus tested their orientation either toward the food oils or the empty vial. The maximum trap catch was recorded at distances up to 60 cm from the pheromone and with the presence of air flow. The oils having botanical origin successfully attracted adults than those of animal origin. It is concluded that the orientation of T. castaneum adults varies with the distance from pheromone, air flow and the nature of food oil
The responses of Tribolium castaneum to wheat germ oil and fungal produced volatiles: Presentation
Get PDFThe red flour beetle Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) is a significant pest affecting a wide variety of different stored products around the Globe. Despite its economic impact, there is evidence that the lures currently used in traps to monitor for this species are largely ineffective. Based on the evolutionary history of T. castaneum, and the ecological niche it occupies, the volatiles of wheat germ oil and volatiles produced by grain-associated fungi have the potential to act as attractants for this species. We used electroantennography (EAG) to measure the electrophysiological response elicited by sixty-eight volatile compounds found in wheat germ oil and/or grain-associated fungi in two T. castaneum strains; an established lab population (CTC12 strain) and a recently caught wild population. Many volatile compounds from both sources elicited strong antennal depolarisations, and the responses of both strains were highly correlated. We then tested whether the compounds that triggered the strongest antennal depolarisations also elicited behavioural responses by using Y-tube olfactometer bioassays and identified several compounds attractive to both strains. The discovery of novel compounds that elicit strong EAG signals and behavioural responses could prove useful in the design of improved lures for T. castaneum and other stored product pests. Our future research will identify how effective these attractive volatiles might be when used in combination, and when used under conditions that more closely replicate a stored product environment.The red flour beetle Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) is a significant pest affecting a wide variety of different stored products around the Globe. Despite its economic impact, there is evidence that the lures currently used in traps to monitor for this species are largely ineffective. Based on the evolutionary history of T. castaneum, and the ecological niche it occupies, the volatiles of wheat germ oil and volatiles produced by grain-associated fungi have the potential to act as attractants for this species. We used electroantennography (EAG) to measure the electrophysiological response elicited by sixty-eight volatile compounds found in wheat germ oil and/or grain-associated fungi in two T. castaneum strains; an established lab population (CTC12 strain) and a recently caught wild population. Many volatile compounds from both sources elicited strong antennal depolarisations, and the responses of both strains were highly correlated. We then tested whether the compounds that triggered the strongest antennal depolarisations also elicited behavioural responses by using Y-tube olfactometer bioassays and identified several compounds attractive to both strains. The discovery of novel compounds that elicit strong EAG signals and behavioural responses could prove useful in the design of improved lures for T. castaneum and other stored product pests. Our future research will identify how effective these attractive volatiles might be when used in combination, and when used under conditions that more closely replicate a stored product environment
Behaviour of the Angoumois grain moth (Sitotroga cerealella Oliv.) in different grain substrates and assessment of losses: Poster
No full textThe Angoumois grain moth, Sitotroga cerealella, is a primary stored grain pest, which development occurs within a single grain. The respond of the pest to various offered grain substrates was studied in no choice laboratory experiment (temperature 27±1ºC; relative humidity 60-80%), by rearing moth populations on entire grains (corn, wheat, barley, sorghum, millet, tall fescue and Kentucky bluegrass) and mechanically damaged grains (corn in fractions with/without embryo, polished rice). The pest behaviour was determined by observation of the entrance and exit hole position on different grains. The food consumption was estimated after adult emergence, by measuring of mass losses of infested grains. Mass losses were correlated with quantitative and qualitative grain parameters. The development was successfully accomplished in all grain substrates, except in Kentucky bluegrass. Strategies of larval penetration and exit hole position depended on morphological properties of grains. As a rule, the development of an individual was completed in a single grain, but in polished rice the transfer from one to another grain was observed. The highest loss of infested grain was recorded in corn grains (55.48 mg), the lowest in tall fescue grains (2.40 mg). Positive correlations were detected between the mass losses and protein, lipid and sugar content, negative in relation to cellulose and ash content.The Angoumois grain moth, Sitotroga cerealella, is a primary stored grain pest, which development occurs within a single grain. The respond of the pest to various offered grain substrates was studied in no choice laboratory experiment (temperature 27±1ºC; relative humidity 60-80%), by rearing moth populations on entire grains (corn, wheat, barley, sorghum, millet, tall fescue and Kentucky bluegrass) and mechanically damaged grains (corn in fractions with/without embryo, polished rice). The pest behaviour was determined by observation of the entrance and exit hole position on different grains. The food consumption was estimated after adult emergence, by measuring of mass losses of infested grains. Mass losses were correlated with quantitative and qualitative grain parameters. The development was successfully accomplished in all grain substrates, except in Kentucky bluegrass. Strategies of larval penetration and exit hole position depended on morphological properties of grains. As a rule, the development of an individual was completed in a single grain, but in polished rice the transfer from one to another grain was observed. The highest loss of infested grain was recorded in corn grains (55.48 mg), the lowest in tall fescue grains (2.40 mg). Positive correlations were detected between the mass losses and protein, lipid and sugar content, negative in relation to cellulose and ash content
Progeny production by Stegobium paniceum in different spices: Poster
No full textSpices have long been an important component in the preparation of food, and some have medicinal properties as well. Stegobium paniceum, the drugstore beetle, has been detected in spices but no detailed information is available on its infestation in certain locally-available spices. Objective of this study was to find out the degree of infestation by S. paniceum in ten different spices. Twenty adults of S. paniceum were introduced into a vial containing a particular spice, maintained for two weeks and shifted out. These were maintained under ambient environmental conditions and the progeny adults emerged in each medium was counted at two week intervals for three months. The progeny produced varied with the food medium; the highest progeny was recorded in coriander whereas the lowest progeny was recorded in cinnamon, clove, dill seeds, cardamom, chilli, pepper corn and turmeric powder. This study reveals that S. paniceum infests a wide array of spices at different levels. This information is important for taking necessary steps to protect the spices from the infestation of S. paniceum.Spices have long been an important component in the preparation of food, and some have medicinal properties as well. Stegobium paniceum, the drugstore beetle, has been detected in spices but no detailed information is available on its infestation in certain locally-available spices. Objective of this study was to find out the degree of infestation by S. paniceum in ten different spices. Twenty adults of S. paniceum were introduced into a vial containing a particular spice, maintained for two weeks and shifted out. These were maintained under ambient environmental conditions and the progeny adults emerged in each medium was counted at two week intervals for three months. The progeny produced varied with the food medium; the highest progeny was recorded in coriander whereas the lowest progeny was recorded in cinnamon, clove, dill seeds, cardamom, chilli, pepper corn and turmeric powder. This study reveals that S. paniceum infests a wide array of spices at different levels. This information is important for taking necessary steps to protect the spices from the infestation of S. paniceum
Investigation on the species and distribution of stored grain insects in northwest China: Poster
No full textTo understand the diversity of stored grain insects in northwest China, we have fulfilled insect collection in 56 grain storage enterprises, 60 grain, oil and feed processing plants and 65 farmers situated in 26 cities of five provinces (Shaanxi, Gansu, Qinghai, Ningxia and Xinjiang) in northwest China from 2016 to 2017. After systematical identification, totally 83 species of stored grain insects have been found in this investigation, belonging to five orders, namely Class Insecta Order Zygentoma, Order Coleoptera, Order Lepidoptera and Order Hymenoptera, as well as Class Arachnida Order Chelonethida, in which Order Coleoptera owns 74 species in 22 families, Order Lepidoptera owns six species in four families, Order Zygentoma and Order Hymenoptera own one species in one family respectively, and Class Arachnida Order Chelonethida has one species in one family. After the statistics of four insect investigations in northwest China during 1955-2017, this paper has analyzed the results of four insect investigations and the representative stored grain insects in northwest China.To understand the diversity of stored grain insects in northwest China, we have fulfilled insect collection in 56 grain storage enterprises, 60 grain, oil and feed processing plants and 65 farmers situated in 26 cities of five provinces (Shaanxi, Gansu, Qinghai, Ningxia and Xinjiang) in northwest China from 2016 to 2017. After systematical identification, totally 83 species of stored grain insects have been found in this investigation, belonging to five orders, namely Class Insecta Order Zygentoma, Order Coleoptera, Order Lepidoptera and Order Hymenoptera, as well as Class Arachnida Order Chelonethida, in which Order Coleoptera owns 74 species in 22 families, Order Lepidoptera owns six species in four families, Order Zygentoma and Order Hymenoptera own one species in one family respectively, and Class Arachnida Order Chelonethida has one species in one family. After the statistics of four insect investigations in northwest China during 1955-2017, this paper has analyzed the results of four insect investigations and the representative stored grain insects in northwest China
Assessing drivers of maize storage losses in south west Benin using a Fractional Response Model: Poster
Get PDFAn assessment of drivers of maize storage losses was undertaken in south west Benin applying the Fractional Response Model on information collected from 400 smallholder maize farmers. Overall, respondents lose on average 10.3% of their harvest during the storage period. The average marginal effect obtained from the fractional response model of storage losses revealed that storage technologies, farmers’ post-harvest attitudes, insects damage, the weather conditions and infrastructures played a significant role in the level of storage losses surveyed farmers have experienced. Farmers using bags and plastic containers have respectively reduced their storage losses by 6.7 and 7.8% compared to farmers using cribs. Considering the use of storage protectant, the results indicated that using ash, neem leaves, pepper or lemon lead to an increase of 4.1% of losses relative to storing without any protectant. Drying after harvesting decreased by 1.9% the share of the quantity stored lost during storage. The percentage of maize lost increased by 5.1% for respondents who have reported insects as predators of their stored maize. Rain at harvest time increased the percentage of losses by 2.1%. A one-degree increase in temperature increased the percentage of maize loss by 4.4% and farmers who live at less than 26.5 km to the market have reduced by 0.17% of maize losses. Effective policies for a sustainable reduction of storage losses among maize farmers in the area should consider the need to discourage the use of cribs, ash, leaves, pepper and lemon as storage technologies. Farmers should avoid harvesting during times of rain, and should properly dry their produce after harvesting. Sustainable hermetic equipment should be promoted and farmers’ access to markets facilitated.An assessment of drivers of maize storage losses was undertaken in south west Benin applying the Fractional Response Model on information collected from 400 smallholder maize farmers. Overall, respondents lose on average 10.3% of their harvest during the storage period. The average marginal effect obtained from the fractional response model of storage losses revealed that storage technologies, farmers’ post-harvest attitudes, insects damage, the weather conditions and infrastructures played a significant role in the level of storage losses surveyed farmers have experienced. Farmers using bags and plastic containers have respectively reduced their storage losses by 6.7 and 7.8% compared to farmers using cribs. Considering the use of storage protectant, the results indicated that using ash, neem leaves, pepper or lemon lead to an increase of 4.1% of losses relative to storing without any protectant. Drying after harvesting decreased by 1.9% the share of the quantity stored lost during storage. The percentage of maize lost increased by 5.1% for respondents who have reported insects as predators of their stored maize. Rain at harvest time increased the percentage of losses by 2.1%. A one-degree increase in temperature increased the percentage of maize loss by 4.4% and farmers who live at less than 26.5 km to the market have reduced by 0.17% of maize losses. Effective policies for a sustainable reduction of storage losses among maize farmers in the area should consider the need to discourage the use of cribs, ash, leaves, pepper and lemon as storage technologies. Farmers should avoid harvesting during times of rain, and should properly dry their produce after harvesting. Sustainable hermetic equipment should be promoted and farmers’ access to markets facilitated
Static and dynamic stress analysis of flat bottom-bamboo reinforced concrete silo for rough rice storage: Presentation
No full textConcrete silos are one of the most robust and reliable structures for grain storage in tropical countries. This study analysed the structural behavior of a low cost, flat bottom bamboo-reinforced concrete (BRC) silo for rough rice storage. This research included the design and development of a BRC silo in accordance with the guidelines mentioned by the Indian Standard (IS) codes. The Finite Element Method was employed to develop the stress profile in the silo walls under “grain at rest” and “grain filling” conditions. The results obtained were further compared with experimental results, classic silo theories (Janssen’s theory) and standards of different countries in the world. The numerical technique gave stress magnitudes very close to those of the experimental results. The classic theories as well as the standards of different countries predicted an over estimation of the magnitude of stresses in the BRC silo. This would result in extra cost of construction of BRC silos. The study also suggested that the vertical stresses were most predominant under static and filling conditions. Maximum stresses were developed at the silo bottom. This study is expected to aid the development of economical silos with minimum wall thickness and material requirement which are ideal for on-site construction and use by smallholder farmers.Concrete silos are one of the most robust and reliable structures for grain storage in tropical countries. This study analysed the structural behavior of a low cost, flat bottom bamboo-reinforced concrete (BRC) silo for rough rice storage. This research included the design and development of a BRC silo in accordance with the guidelines mentioned by the Indian Standard (IS) codes. The Finite Element Method was employed to develop the stress profile in the silo walls under “grain at rest” and “grain filling” conditions. The results obtained were further compared with experimental results, classic silo theories (Janssen’s theory) and standards of different countries in the world. The numerical technique gave stress magnitudes very close to those of the experimental results. The classic theories as well as the standards of different countries predicted an over estimation of the magnitude of stresses in the BRC silo. This would result in extra cost of construction of BRC silos. The study also suggested that the vertical stresses were most predominant under static and filling conditions. Maximum stresses were developed at the silo bottom. This study is expected to aid the development of economical silos with minimum wall thickness and material requirement which are ideal for on-site construction and use by smallholder farmers
