Percentage Of Damaged Grains Research Articles

Toxicity and repellency of essential oils against the maize weevil Sitophilus zeamais (Motschulsky, 1855) (Coleoptera: Curculionidae)

Usually, Sitophilus zeamais control is carried out through chemical fumigation, which is relatively effective, albeit highly toxic, potentially causing damage to the agroecosystem. In the search for alternative management methods, research on the use of essential oils has increased, as they contain compounds with insecticidal action. The aim of the present study was to verify the effects of some essential oils on S. zeamais. Glass jars were used as fumigation chambers, with a filter paper on the lid, where 20 µL of each essential oil were pipetted. The oils of Piper nigrum, Melaleuca alternifolia, Lavandula officinalis, and Foeniculum vulgare were used. After 24 hours, mortality assessment was conducted by counting the number of dead insects. The repellency test was executed through an arena system with 5 plastic containers arranged equidistantly in a circle. In the central container, 5 adult female S. zeamais were placed in each repetition, and in the others, 20 g of corn were placed in each, with two treated with a 2% essential oil solution in distilled water and Tween 80® and two treated only with distilled water and Tween 80®. After 72 hours, repellency evaluation was performed by counting the number of insects in each container and the percentage of damaged grains. It was observed that the essential oils showed moderate toxicity against S. zeamais; however, they exhibited repellency at the evaluated dose. It is concluded that the tested essential oils have repellent properties against S. zeamais and can be used as a control method.

Performance Evaluation of an Imported Machine for Corn Threshing

The aim of the study is to evaluate the performance of an imported threshing machine and modified locally under different speeds for the threshing cylinder (1416, 1814) RPM, using two cultivars of corn: the first (KN-30) and the second (S6668), and three feed rates (1, 2, 3) kg. The experiment was conducted using a split plot design according to the randomized complete block design, with three replications. Some indicators were studied, including the required specific energy, Percentage of damaged grains, threshing efficiency, productivity, and electrical energy consumption. The results showed that the rotational speed of 1814 RPM had a significant effect on specific energy, electrical energy consumption, threshing efficiency, and productivity. The third feed rate (3 kg) had a significant effect on specific energy and productivity. while for the second cultivar of corn (S6668), it had a significant effect on specific energy, Percentage of damaged grains, and productivity.

Evaluation the performance of the locally Developed Corn Thresher Machine from Manual to Mechanical System

This study was conducted to develop corn thresher located in the College of Agriculture and Forestry, University of Mosul - Iraq in 2022, and this thresher operated by manual system. 1The factors were studied using two varieties of corn (Rayal, ZP), rotation speed 50, 100 rpm, and clearance between threshing wheel and pressing plate 10, 20 mm on some indicators, namely: productivity (kg.h-1), percentage of damaged grains (%), percentage of non-threshed grains (%).Operating costs (dinars. kg-1), the experiment was implemented according to a Complete Randomized Design (CRD), and with three replications .The main objectives of the study were to develop a manual system of thresher machine and to select the most appropriate operating factors that affect its performance. The results of the study showed that the (Rayal) variety was superior to the (ZP) variety in recording the lowest percentage of damaged grains. The rotation speed 100 rpm achieved the highest productivity values and the lowest values for each of (percentage of non-threshed grains, Operating costs), The clearance 20 mm was superior in achieving the highest values for productivity and the lowest values for the percentage of damaged grains, while the clearance 10 mm achieved the lowest values for the percentage of non-threshed grains.

Assessment of field traits, nutrient composition and digestible amino acids of corns with different endosperm textures for poultry and swine

An experiment was conducted to evaluate field traits and nutrient composition of four corn types presenting distinct endosperm textures. A total of 213 samples of different corn hybrids from a field experiment conducted in Brazil were separated into 4 groups according to the endosperm texture classification: dent (n = 30), flint (n = 51), semi-dent (n = 60) and semi-flint (n = 72). Crop yield, thousand grains weight and damaged grains were determined. Nutritional composition as well as digestible amino acids (AA) and metabolizable energy values for poultry and swine of the four corn types were predicted by near infrared spectroscopy. Data were submitted to analysis of variance and mean differences of corn types were separated by Tukey’s test at 5% of significance. Principal component analysis was performed for the main nutritional variables and damaged grains. Starch concentration was greater (P < 0.01) in dent than in flint corn. Dent corn presented higher percentage of damaged grains (P < 0.01) than the other types. Flint corn had the lowest crop yield (P < 0.001); however, this corn texture presented the higher crude protein, total Cys, Thr, Arg, Ile, Leu, Val, His, Gly, Ser, Pro, Ala and Glu contents than the remaining three types (P < 0.001). The flint type had also the highest (P < 0.0001) content of most of digestible AA for swine and poultry. Energy values were not different among corn types (P > 0.05). In conclusion, field traits and nutritional composition of corn vary depending on the characteristic of its endosperm, and such differences should be considered by the corn and feed production chains.

Comparison between devices for homogenization and reduction of soybean grain samples

In the grain market the most diverse equipment is used for homogenization and reduction of the working samples. Thus, this paper aims to analyze the performance of devices used for sample homogenization and reduction for soybean classification. A sample composed of 8% of damaged soybeans with yellow and black coat was previously prepared. Samples were homogenized and reduced in bucket, crate, Boerner, 16:1 multichannel splitter and 4:1 multichannel splitter. The design used was completely randomized with five treatments (homogenizers) and one percentage of damaged grains (8%). Evaluations were subjected to analysis of variance and treatment means were compared to one another by Tukey test (p 0.5) and to the mean of the original sample (8%) by Student s t-test. The devices Boerner, 16:1 multichannel splitter and 4:1 multichannel splitter were similar in the homogenization and reduction of the soybean sample. The crate and bucket showed the worst performance in the grain homogenization because they compromise the result of the product’s qualitative analysis.

Essential oil from Duguetia lanceolata St.-Hil. (Annonaceae): Suppression of spoilers of stored-grain

To search for new compounds with promising grain-protective properties, this study evaluated the chemical composition and insecticidal, antifungal and antiaflatoxigenic activities of essential oil (EO) from the hydrodistillation of Duguetia lanceolata (Annonaceae) leaves on fungi and insects that spoil stored commodities. By combining the chromatographic and spectroscopic analyses, 5 compounds were identified in the EO of D. lanceolata leaves, including the major compounds β-bisabolene (56.2%) and 2,4,5-trimethoxystyrene (19.1%). This EO showed promising lethal effects on adult Sitophilus zeamais (LC50 = 457 mg kg−1) and Zabrotes subfasciatus (LC50 = 442 mg kg−1) using a residual contact bioassay. In addition to lethal effects, the EO strongly reduced the number of adult S. zeamais that emerged from the treated samples (EC50 = 480 mg kg−1), the percentage of damaged grains (EC50 = 543 mg kg−1) and the sample weight loss (EC50 = 543 mg kg−1). For Z. subfasciatus, D. lanceolata EO significantly reduced the number of eggs/sample (EC50 = 118 mg kg−1), the number of emerged insects (F1 progeny; EC50 = 119 mg kg−1) and the percentage of damaged grains (EC50 = 148 mg kg−1). However, the EO led to no significant mortality in adults of either species using fumigation. The EO also inhibited radial growth and aflatoxin B1 production in the CCT7638 Aspergillus flavus isolate (Ascomycota) in a concentration-dependent manner. Thus, the EO of D. lanceolata leaves may be a promising source of compounds with potential grain-protective properties.

PP-APR11-050: Histological assessment of beef muscle tenderized by stretch method

To search for new compounds with promising grain-protective properties, this study evaluated the chemical composition and insecticidal, antifungal and antiaflatoxigenic activities of essential oil (EO) from the hydrodistillation of Duguetia lanceolata (Annonaceae) leaves on fungi and insects that spoil stored commodities. By combining the chromatographic and spectroscopic analyses, 5 compounds were identified in the EO of D. lanceolata leaves, including the major compounds β-bisabolene (56.2%) and 2,4,5-trimethoxystyrene (19.1%). This EO showed promising lethal effects on adult Sitophilus zeamais (LC50 = 457 mg kg−1) and Zabrotes subfasciatus (LC50 = 442 mg kg−1) using a residual contact bioassay. In addition to lethal effects, the EO strongly reduced the number of adult S. zeamais that emerged from the treated samples (EC50 = 480 mg kg−1), the percentage of damaged grains (EC50 = 543 mg kg−1) and the sample weight loss (EC50 = 543 mg kg−1). For Z. subfasciatus, D. lanceolata EO significantly reduced the number of eggs/sample (EC50 = 118 mg kg−1), the number of emerged insects (F1 progeny; EC50 = 119 mg kg−1) and the percentage of damaged grains (EC50 = 148 mg kg−1). However, the EO led to no significant mortality in adults of either species using fumigation. The EO also inhibited radial growth and aflatoxin B1 production in the CCT7638 Aspergillus flavus isolate (Ascomycota) in a concentration-dependent manner. Thus, the EO of D. lanceolata leaves may be a promising source of compounds with potential grain-protective properties.

Toxicity of an Annonin-Based Commercial Bioinsecticide Against Three Primary Pest Species of Stored Products.

The effects of a bioinsecticide formulation based on extract of Annona squamosa L. (Annonaceae) containing 10,000mgL-1 of acetogenin annonin as the main active ingredient were investigated against three primary pest species of stored grains in Brazil [maize weevil Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae), Mexican bean weevil Zabrotes subfasciatus (Boheman) (Coleoptera: Chrysomelidae: Bruchinae), and cowpea weevil Callosobruchus maculatus (Fabricius) (Coleoptera: Chrysomelidae: Bruchinae)] by means of residual contact bioassays. In a concentration-dependent manner, the annonin-based commercial bioinsecticide caused significant adult mortality of C. maculatus (LC50=6890μLkg-1), S. zeamais (LC50=2781μLkg-1), and Z. subfasciatus (LC50=2120μLkg-1) after 120h of residual contact exposure. In addition to acute toxicity, the tested bioinsecticide also promoted a significant reduction of the number of eggs laid by females of C. maculatus (EC50=5949.7μLkg-1) and Z. subfasciatus (EC50=552.7μLkg-1). Moreover, the bioinsecticide significantly reduced the number of emerged insects (F1 generation) of C. maculatus (EC50=2763.0μLkg-1), S. zeamais (EC50=1380.8μLkg-1), and Z. subfasciatus (EC50=561.5μLkg-1). The bioinsecticide also reduced the percentage of damaged grains for the three pest species studied, and its grain-protectant properties are comparable to or superior in efficacy in relation to a diatomaceous earth-based insecticide (Insecto® at 1000mgkg-1) used as a positive control. Thus, this standardized formulation has promising bioactivity against stored insect species and can be a useful component for IPM of stored grains in Brazil and elsewhere.

Resistance of Rice Varieties to the Stored-Product Insect, Sitophilus zeamais (Coleoptera: Curculionidae).

Four common Portuguese rice varieties--Thaibonnet, Gladio, Albatros, and Eurosis--were tested for their relative susceptibility to Sitophilus zeamais Motschulsky, a common pest of stored rice in Portugal and in tropical countries. Physical (moisture content, hardness, length, and width) and chemical (by attenuated total reflection-Fourier transform infrared spectroscopy) properties of rice kernels were measured. Insect bioassays measured median developmental time, Dobie's index of susceptibility, percentage of damaged grains and weight loss, and progeny developed. This was done for paddy, brown rice, and polished rice for each variety. There were small, but significant, differences in insect resistance among the varieties. However, it was different for paddy and polished rice. In paddy, these differences were correlated with hull damage, and Eurosis was the most susceptible variety. In polished rice, resistance was correlated with hardness, and Thaibonnet was the most susceptible variety. In general, paddy rice was more resistant to insect attack, followed by polished rice and then brown rice. Paddy kernels selected with undamaged hull were completely resistant to attack. Implications for IPM and breeding for resistant varieties are discussed.

Pimenta pseudocaryophyllus Derivatives: Extraction Methods and Bioactivity Against Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae).

Plant-based insecticides can play an important role in integrated insect pest management (IPM), especially in protecting stored grains. The aim of this study was to evaluate the bioactivity of derivatives (powder, ethanolic extract, and essential oil (EO)) from the leaves of Pimenta pseudocaryophyllus (Myrtaceae), a Brazilian native species, against Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae), the main insect pest of stored corn. The powder and essential oil prepared from leaves showed a repellent effect. Moreover, the EO exhibited promising insecticidal activity through residual contact (LC50 = 1522 mg kg(-1)) and significantly decreased the F 1 progeny and the percentage of damaged grains. However, the essential oil obtained from P. pseudocaryophyllus leaves did not result in significant mortality of S. zeamais adults after 72 h of exposure by fumigation in concentrations up to 400 μL L(-1) of air. Based on GC-MS analysis, 20 compounds were identified in the essential oil of P. pseudocaryophyllus leaves, being chavibetol (38.14%), methyl eugenol (11.35%), and terpinolene (9.17%) as the major constituents. Essential oil from P. pseudocaryophyllus leaves is an interesting source of compounds with grain-protectant properties and should be analyzed in future studies aiming to develop new bioinsecticides to use in the IPM of stored grains.

Comparison of seven methods for stored cereal losses to insects for their application in rural conditions

There are several methods for assessing harvest losses during storage with varying degrees of accuracy, reliability and practical application, however, field conditions may limit their use among subsistence farmers and traders in developing nations. We compared seven standard grain loss methods during natural and controlled infestation by Sitophilus oryzae L. in wheat and barley to select the best procedures for use in farm storage. Methods tested were: 1) visual inspection of infested lots, 2) uncorrected weight loss, 3) modified standard volume/weight ratio, 4) grain count and weight, 5) percentage of damaged grains converted to weight loss, 6) one thousand grain mass, and 7) one thousand grain mass including dust. Previously disinfested cereal lots (wheat, barley, 500 g fresh w) were exposed to 20 newly emerged adult S. oryzae for 90 d at 28 °C and 70% r.h. Naturally- infested wheat lots were also monitored under the same conditions. Before and after this period, fresh and dry weight, number, moisture content of uninfested and damaged grains, weight of 1 L of seeds and dust produced by insect activity, fresh and dry weight of 1000 kernels, and number of adult weevils was determined and applied to appropriate equations of methods (1)–(7). Grain mass loss estimations varied by wide margins (9.3 ± 1.3% to 25.8 ± 2.3% in barley, 2.2 ± 0.7% to 12.5 ± 2.5% in wheat) depending on method employed, suggesting the need for careful selection of the most appropriate procedure under field conditions and farmer/trader interests. While accurate procedures such as method 7 provided dependable results, methods 3 and 5 appear most practical for wheat and barley.

Neem oil antifeedant and insecticidal effects on Oebalus poecilus (Hemiptera: Pentatomidae) males and females

The antifeedant and insecticidal effects of two commercial neem (Azadirachta indica) oil formulations (Dalneem and Nim-I-Go) to Oebalus poecilus were evaluated on irrigated rice. To evaluate the antifeedant effect, both formulations were tested at 1% and 2% (v/v) concentration levels. The insecticidal effect was evaluated at 0.5%, 1%, 2%, and 4% (v/v) concentrations of Dalneem, by ingestion. Both experiments were conducted with four replications by treatment, containing one panicle and adult insects segregated by gender (two insects per plot for the antifeedant effect and five for the insecticidal effect). Both products were efficient, reducing the damage caused by insects. Insects fed less on the panicles treated with neem oil, causing lower number of feeding sheaths per panicle and lower percentage of damaged grains than the control. Spikelets weight was higher in panicles treated with neem oils. Females caused significantly higher damage than males in controls, for numbers of feeding sheaths and for the feeding deterrence index. Only at the 4% (v/v) concentration level, Dalneem caused adult mortality higher than in the control. Results showed that neem oil formulations, at &gt; 1% (v/v) concentration, can be used to reduce the quantitative and qualitative damages caused by O. poecilus in lowland rice.

EFEITO INSETICIDA E DETERRENTE DO ÓLEO DE NIM EM MACHOS E FÊMEAS DE Oebalus poecilus (HEMIPTERA: PENTATOMIDAE)

The antifeedant and insecticidal effects of two commercial neem (Azadirachta indica) oil formulations (Dalneem and Nim-I-Go) to Oebalus poecilus were evaluated on irrigated rice. To evaluate the antifeedant effect, both formulations were tested at 1% and 2% (v/v) concentration levels. The insecticidal effect was evaluated at 0.5%, 1%, 2%, and 4% (v/v) concentrations of Dalneem, by ingestion. Both experiments were conducted with four replications by treatment, containing one panicle and adult insects segregated by gender (two insects per plot for the antifeedant effect and five for the insecticidal effect). Both products were efficient, reducing the damage caused by insects. Insects fed less on the panicles treated with neem oil, causing lower number of feeding sheaths per panicle and lower percentage of damaged grains than the control. Spikelets weight was higher in panicles treated with neem oils. Females caused significantly higher damage than males in controls, for numbers of feeding sheaths and for the feeding deterrence index. Only at the 4% (v/v) concentration level, Dalneem caused adult mortality higher than in the control. Results showed that neem oil formulations, at &gt;= 1% (v/v) concentration, can be used to reduce the quantitative and qualitative damages caused by O. poecilus in lowland rice. KEY-WORDS: Small rice stink bug; Azadirachta indica; qualitative damages; Oryza sativa; botanical extract.

Quantificação da área foliar e efeito da desfolha em componentes de produção de milho

A redução da área foliar em plantas de milho altera a atividade fisiológica e consequentemente o rendimento de grãos. Os objetivos deste trabalho foram quantificar a área foliar em milho e avaliar as consequências de diferentes níveis de desfolha nos componentes de produção. O experimento foi realizado em Uberlândia, Minas Gerais (MG), durante o ano agrícola de 2007/2008. O delineamento experimental foi em blocos casualizados, com cinco repetições. Os tratamentos foram testemunha sem desfolha, remoção de duas folhas apicais, remoção de quatro folhas apicais, remoção de todas as folhas acima da espiga, remoção de quatro folhas intermediárias, remoção de todas as folhas abaixo da espiga e remoção de todas as folhas da planta. O genótipo utilizado foi o híbrido NB7376. A quantificação da área foliar foi realizada a partir da submissão de imagens de folhas de milho para leitura no programa QUANT 1.0. O resultado da área média foliar do híbrido foi de 5.687,72cm² por planta, e o Índice de Área Foliar é de 4,4. Quando foram retiradas todas as folhas acima da espiga, foi observada a perda de 20% na produtividade e de 8% no peso de 1.000 grãos; no entanto, não foram alterados a porcentagem de grãos ardidos, o número de grãos, o número de fileiras por espiga, o estande e a porcentagem de plantas acamadas. A porcentagem de grãos ardidos e de plantas acamadas só foi afetada em desfolhas totais. Toda a área foliar em milho tem a sua participação na produção de fotoassimilados; no entanto, a extensão foliar fisiologicamente ativa acima da espiga é caracterizada como a mais eficiente na produtividade de grãos.

Effect of selenium, molybdenum and zinc on seedling growth and frequency of grain weevil (Sitophilus granarius) in triticale grains

The effects of different doses (0, 90, 270, 810 kg/ha) of selenium, molybdenum and zinc microelements on their translocation and accumulation in grains, seedling growth and grain infestation were examined under field conditions on a calcareous chernozem soil. Thirteen years after the application of selenium, molybdenum and zinc, significant translocation and accumulation of these elements in the grain were established, indicating a long-term effect of these microelements on triticale plants. The highest degree of accumulation in grains and seedling shoots was found for selenium, then molybdenum, while the detected amounts of zinc were significantly lower. The degree of accumulation of all three microelements in the grain and seedling shoot increased as doses increased. Translocation index from shoot to grain at the grain-filling phase was the highest when zinc was used, then selenium, and the lowest when molybdenum was applied. The highest translocation index from the grain during germination into seedling shoots was obtained with zinc, then molybdenum and selenium. Translocation indexes of the investigated elements significantly decreased as the doses of elements increased. Dry weight of seedling shoots decreased as molybdenum and zinc in grain increased. High selenium concentration moderately stimulated seedling development, pointing out a high tolerance of triticale to higher concentration of this microelement at initial development stages. Infestatation with grain weevil was provoked by high concentrations of these microelements in the grain. High concentrations of zinc and selenium, in particular, significantly decreased the percentage of damaged grains, while molybdenum moderately increased their numbers. The effect of zinc and molybdenum may be attributed to their chemical effect, while selenium effect may also be referred to a negative effect of the volatile selenium compound. The effect of selenium, molybdenum and zinc contamination of grains on the seedling growth and frequency of grain weevil was different, and the emphasis was on selenium.

Efeito de inseticidas sistêmicos aplicados no solo na produção do feijoeiro

Este trabalho objetivou o estudo dos componentes de produção na cultura do feijoeiro (Phaseolus vulgaris L.), quando se utilizaram os inseticidas sistêmicos Aldicarb 150 G (6 kg/ha) e Fosthiazate 100 G (10, 20, 30 e 40 kg/ha), além da testemunha. A pesquisa foi desenvolvida na Universidade Federal de Viçosa, Viçosa (MG), em abril-julho de 1994. O delineamento experimental foi em blocos casualizados com quatro repetições, sendo a unidade experimental constituída de 500 plantas. Avaliaram-se altura das plantas, número de nós, mortalidade de plantas, número de flores, vagens, óvulos e grãos danificados (identificando-se os causadores dos danos). Foi estimada a produtividade média de cada tratamento, as perdas ocorridas e suas causas. A partir desses dados, confeccionou-se tabela de vida para a cultura. Não se verificou efeito dos inseticidas Aldicarb e Fosthiazate quanto à altura e ao número de nós das plantas de feijoeiro. O componente de produção que mais sofreu perdas foi a vagem devido ao ataque de Etiella zinckenella (Treitschke) (Lepidoptera: Pyralidae)] seguido da mortalidade de plantas na fase vegetativa e grãos (pelo ataque do fungo Colletotrichum lindemuthianum). A flutuação de perdas totais foi mais influenciada pela mortalidade de plantas seguida pelo abortamento de flores. Ocorreu menor mortalidade de plantas na fase vegetativa com o aumento na dosagem de Fosthiazate.

Quality losses in wheat caused by the orange wheat blossom midge Sitodiplosis mosellana

SummaryIn three sets of data pooled over spring wheat varieties and lines a number of grain quality measurements were related to the levels of infestation by Sitodiplosis mosellana larvae. The Hagberg falling number value was negatively correlated with the proportion of damaged grains. The 1000‐grain weight, protein content and gluten content were not affected. Differences between cultivars in infestation and damage level were found to depend on the development phenology (timing of ear emergence) and on the percentage of damaged grains remaining in the yield after harvest. The falling number values were reduced most when the attainable values remained low in cultivars prone to sprouting damage, and in seasons with unfavourable weather conditions for quality maintenance.The proportion of damaged grains in relation to the number of larvae was well described by a logit‐transformed regression. Sampling for infestation level and preventive measures against quality loss are discussed.

Observations on prolonged grain storage with forced aeration in Israel

Observations were carried out for 22 months on 1142 tonnes of wheat stored in a metal bin equipped with an aeration system and a fan withdrawing air at a rate of 5150 ft 3/min. The observations comprised temperature measurements of the grain bulk, records of the ambient temperature and humidity and of the hours of fan operation, and examination of grain condition as indicated by moisture content, germination, insect infestation, and the percentage of damaged grains. The observations showed that during the first year beginning in May 1966, 1212 hr of aeration lowered the temperature of different layers of the grain bulk from averages of 26·8–32·2°C to 10·2–13·8°C. During the summer of the second year the grain temperature rose to averages of 18·1–19·2°C. During the second winter of storage, 523 aeration hr cooled the grain bulk to averages of 10·5–14·3°C. The grain remained in excellent condition throughout the almost 2 years storage period.