Thousand-grain Mass Research Articles

Can Soil Compaction Alter Morphophysiological Responses and Soybean Yield under Application of Selective Herbicides?

Compacted soils may be negatively affecting the selectivity of herbicides applied in preemergence in the soybean crop. Therefore, the present work aimed to investigate possible negative effects on the morphophysiological characters of soybean plants, as well as on the agronomic and yield performances of this crop. For this purpose, two trials were carried out, one in a greenhouse and the other under field conditions. In a greenhouse, the study was carried out in a completely randomized design in a 2 × 8 factorial, with five replications, while in the field, the design used was randomized blocks, with the treatments arranged in split-plot (2 × 8), with six repetitions. The first factor/plot corresponded to the physical condition of the soil: compacted or not compacted, while the second factor/subplot was constituted by the application of preemergence herbicides: clomazone, diclosulam, flumioxazin, S-metolachlor, [imazethapyr + flumioxazin], [pyroxasulfone + flumioxazin], and [sulfentrazone + diuron], plus a control without herbicide. In the greenhouse study, there was a significant interaction between soil compaction and herbicides applied in preemergence for the relative index of chlorophyll b and root dry mass. Furthermore, the isolated herbicide factor did not promote significant changes in any of the morphophysiological variables evaluated. Compaction alone had a negative impact on the variables relative index of chlorophyll a and carbon assimilation rate, with reductions in the values of these variables when the soybean was submitted to growth in compacted soil. For the field experiment, there were no significant interactions between the factors for any of the analyzed variables, nor the effect of herbicides alone. The isolated soil compaction factor negatively impacted the plant stand and the thousand-grain mass of soybean, showing reductions in the values of this parameter when the soybean was grown in compacted soil.

Application of ozone at low-pressure: Control of egg and larval phases of Zabrotes subfasciatus, inactivation of Aspergillus flavus and qualitative changes in bean grains

Ozone applied in a low-pressure system has been studied in packed grains. In the present study, we evaluated the effect of ozone applied at low-pressures for the control of egg and larval phases of Zabrotes subfasciatus and inactivation of Aspergillus flavus in beans and possible changes in product quality. Samples of 5.0 kg of beans packed in woven polypropylene bags were exposed to ozone in the hypobaric chamber of internal volume equal to 70 L. The application of ozone was preceded by the reduction of internal chamber pressure to 50000 Pa. The ozone was then injected until the chamber's internal pressure reached 100000 Pa. An inlet ozone concentration of 61.37 mg L−1 was applied in 1, 4, 7, and 10 injections and a flow rate of 1.0 L min−1. In the control treatment, oxygen was used. The ozonation of beans with 10 injections was efficient in controlling the egg and larval phases of Z. subfasciatus, reducing mass loss and inactivation of A. flavus in the grains. The increase in the number of injections increased the electrical conductivity of the beans. However, ozone did not affect the thousand-grain mass, percentage of whole grains after cooking, total soluble solids in the cooking broth, dimensions of the orthogonal axes of the grains, volume and length-width ratio of the cooked beans. The results suggest that the number of injections in the system at low-pressure is a determining factor for the concentration of ozone inside grain packages. In this system, the application of ozone adopting 10 injections is efficient in the control of Z. subfasciatus and in the inactivation of A. flavus, without affecting the quality of the beans.

Correlations of agronomic characteristics of soybean cultivated with the use of organomineral fertilizers

The use of correlations can identify the traits correlated with soybean grain yield. Therefore, the objective of this study is to use path analysis to examine how agronomic traits influence grain yield in soybeans, taking into account different doses and sources of organominerals used in cultivation. The experimental design used was randomized blocks arranged in a sub-subdivided plot with three replications. In the plots, the treatments consisted of two soybean cultivars (BMX Bônus IPRO and BMX Olimpo IPRO), and in the subplot, the treatments consisted of three phosphate fertilizers [two organomineral fertilizers manufactured and a phosphate fertilizer (simple superphosphate)]. The subplot used doses of 0 (control), 50, and 100 kg ha-1 of P2O5. At full flowering, the relative chlorophyll index was evaluated. At physiological maturity, plant height, first pod insertion height, number of stems, pod number, number of grains per pod, thousand-grain mass, and grain yield were evaluated. The plant height variable presented the greatest positive direct effect on the soybean yield cultivated using organomineral fertilizers.

Correlations and path analysis of second-crop corn hybrids for maximum grain yield performance

The aim was to estimate the correlation coefficients and their direct and indirect effects through path analysis between agronomic traits that modulate the grain yield of second-crop corn hybrids. The hybrids SYN7G17 TL, 30F53VYHR, B2433PWU and AG 8700 PRO3 were employed. The following agronomic traits were evaluated: leaf nitrogen content, ear height, ear length, ear diameter, number of rows of grains per ear, number of grains per row, mass of a thousand grains, grain yield and grain protein content. Estimates of phenotypic correlation of all combinations of traits were calculated, and then the development of phenotypic correlations in direct and indirect effects was evaluated through path analysis, where grain yield was considered the main variable and the others were considered explanatory variables. Grain yield correlated strongly and positively with thousand-grain mass (0.83) and ear diameter (0.72). In the path analysis to tested conditions, no significant indirect effect was observed. However, the mass of a thousand grains and the ear diameter had a significant direct effect on the grain yield of corn, indicating that the selection of these characteristics can help to improve the grain yield in lines of corn

Enhancement of Seed Germination, Growth, Yield, and Nutritional Composition Using Low-Frequency Glow Discharge (LFGD) Plasma in Wheat (Triticum Aestivum)

Several factors affect germination and seedling growth for the successful establishment of crops. This study investigates the effect of medium pressure (~10 torr) low-frequency glow discharge (LFGD) (Ar+Air) plasma-treated seeds for different periods (1, 3, 6, 8, and 10 min) of wheat. The scanning electron microscopy (SEM) image of the seed surface showed notable changes due to plasma treatment. The germination results showed a significant increase of 4.35%, and the agronomical parameters exhibited a meaningful upgrade result in treated plants compared to control. The catalase (CAT) and superoxide dismutase (SOD) activities significantly improved in shoot and root of plants along with their expression candidate genes (TaCAT and TaSOD) in roots relative to control. Besides, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity substantially increased in shoots of plants. A dissimilarity effect was observed in ascorbate peroxidase (APX) and the candidate gene for Ta APX. Further, hydrogen peroxide (H2O2), soluble protein, and sugar content showed significant changes in the leaves and roots but not in nitric oxide (NO) due to plasma treatment. In addition, thousand grain mass (TGM) and nutritional compositions including iron grain, iron shoot, manganese grain, fat, fiber, and ash were significantly increased in contrast to controls. Also, zinc concentration showed no changes in plants, while the moisture content showed significant decreases. Thus, these findings unveil the potentialities of LFGD plasma to improve the germination and growth of wheat plants.

Understanding the contribution of soybean crop residues inoculated with Bradyrhizobium spp. and not harvested on nitrogen supply in off-season corn cultivars.

Excessive rainfall in the soybean preharvest period can make mechanized crop harvesting technically and economically unfeasible, causing 100% losses in soybean grain yield. An alternative to reduce the economic losses of farmers would be using unharvested soybean crop residues as a source of nitrogen (N) for the subsequent corn crop. However, a question that still needs to be understood is whether the amount of N released from unharvested soybean residues (straw and grains) is sufficient to meet all the nutritional demand for this nutrient in the off-season corn. Therefore, this study investigated the impact of unharvested soybean crop residue persistence on the yield response of off-season corn crop (Zea mays L.) to the application of N fertilizer rates when grown in tropical Cerrado soils of medium and high fertility. Four simple corn hybrids (SYN7G17 TL, 30F53VYHR, B2433PWU, and AG 8700 PRO3) were grown in soils of medium fertility and medium acidity level (UFMS 1) and high fertility and low acidity level (UFMS 2) and fertilized with five of N fertilizer rates (0, 40, 80, 120, and 160 kg ha–1 of N) applied at 30 days after emergence (DAE). Canonical correlation analysis (CCA) was used to investigate the interrelationships between the groups of independent (agricultural production areas, corn cultivars, and N application rates) and dependent (corn agronomic traits) variables. Crop residues remaining on the soil surface from soybeans not harvested and inoculated with Bradyrhizobium spp. can supply most of the nitrogen requirement of off-season corn grown in succession, especially in tropical soils of medium fertility. However, in high-fertility tropical soils, the maximum grain yield potential of off-season corn cultivars can be obtained with the application of mineral N fertilizer in supplement the amount of nitrogen released from unharvested soybean residues. Therefore, the N requirement depends on the corn cultivar and the agricultural production area. However, our results show that when off-season corn is grown on unharvested soybean residues, nitrogen fertilization in topdressing can be dispensed. The agricultural area with high fertility soil (UFMS 2) enhances the grain yield of the off-season corn crop. The corn cultivar AG 8700 PRO3 has a higher thousand-grain mass and high grain yield potential under Brazilian Cerrado conditions.

Identification of three gene families coordinating the conversion between fructose-6-phosphate and fructose-1,6-bisphosphate in wheat

Saccharides are a direct energy source for most organisms and the primary components in grains of common wheat (Triticum aestivum L., 2n = 6x = 42, AABBDD). However, genes involved in the metabolism of primary saccharides such as glucose and fructose have not been fully characterized in wheat, which limits our understanding of how these genes influence wheat growth. In this study, genes coding ATP-dependent phosphofructokinase (PFK), fructose-1,6-bisphosphatase (FBP), and pyrophosphate-dependent fructose-6-phosphate 1-phosphotransferase (PFP), which participate in the conversion between fructose 6-phosphate (F-6-P) and fructose 1,6-bisphosphate (F-1,6-P2), were identified at the genome-wide level. A total of 24, 13, and 12 genes were found encoding TaPFK, TaFBP, and TaPFP, respectively. All predicted peptides of these genes exhibited conserved substrate-binding domain, suggesting they are active enzymes in vivo. Transcriptome data ranked the gene levels as follows: TacyFBP-1 > TacpFBP-1 > TaPFPα-2 ≈ TaPFPβ >> TaPFK-1 ≈ TaPFK-5 >> all remaining genes at different developmental stages of wheat. In the three tapfp-a, b, and d knockout lines, there was a decrease in the plant height, anther length, and thousand-grain mass, while the percentage of abnormal pollen increased compared to that of wild type cv. Huapei3 (HP3). During germination, tapfpβ-a exhibited a lower germination rate, shorter coleoptile and primary root length, and higher fructose content than HP3, tapfpβ-b, and tapfpβ-d lines. Expressions were ranked as follows: TaPFK-5 ≈ TaPFPα-2 >> TaPFPα-1 ≈ TaPFPβ > TacyFBP-1 ≈ TaPFK-7, 9 in HP3. All these genes were downregulated during the 24 - 96 h germinating process in three mutant lines. Collectively, main TaPFK, TaFBP, and TaPFP members cooperated during wheat growth, while TaPFPβ knockout decreased wheat vitality. Results from this study can aid more systematic studies of the physiological and molecular functions of TaPFK, TaFBP, and TaPFP.

Yield components and nutritional quality of soybean grain as a function of foliar fertilizers application time

Foliar fertilization aims to provide rapid-absorption nutrients to the plant, supplement soil fertilization, and fulfill the uptake peaks’ demand. This study’s objective was to verify the effect of foliar fertilizers application in stages R2 (full bloom) and R5 (beginning seed) on soybean grain quality, yield components, and grain yield. The experiment was conducted in three sites through Parana state (Brazil) in a 9 × 2 factorial design, with three replications per treatment. Total chlorophyll index, plant height, yield components (number of pods per plant, number of grains per pod, number of grains per plant and thousand-grain mass), protein and oil concentration in the grain, and final yield were evaluated. Plant height, total chlorophyll index, and grain quality were not affected by this study’s foliar fertilizers. Thousand-grain mass responded to the foliar products and the application times. However, no final grain yield effect was observed, possibly because those nutrients’ soil level was adequate.

Crop Yield and Physicochemical Properties of Wheat Grains as Affected by Tillage Systems

In this study, we aimed to determine the effects of tillage systems (TS) on wheat grain yield, yield components, and physicochemical properties under rain-fed conditions over 2 years (2018–2019) in the Kuhdasht region in southwestern Iran. The tillage treatments were a combination of conventional tillage (CT), reduced tillage (RT), and no tillage (NT) systems based on randomized complete blocks with three replications. Wheat grain yields and yield components, physical properties (geometrical dimensions, sphericity, thousand-grain mass (TGM), water absorption (WA), volume (V), and density), chemical composition (protein content (PC), water content (WC), fiber content (FC), ash content (AC)), surface color parameters (L*, a*, and b*), and correlations among measured parameters were assessed. The results showed that wheat grain yield and yield components were significantly affected by TS (p < 0.01). The wheat grain yield was higher under CT (2.72 t ha−1), with a significant difference between RT (1.76 t ha−1) and NT (1.20 t ha−1). The highest TGM (49.19 g) was achieved under CT, followed by RT (43.41 g), with the lowest (39.17 g) in the NT system. TS had significant effects on certain physical properties of wheat grains (p < 0.01). Wheat grain, size, shape, and mass values were higher under CT than RT and NT systems in all experimental years. CT resulted in the highest WA, while the lowest resulted from NT. TS had no significant influence on the density of the grains. TS had significant effects on PC, AC, and WC values of grains at the 1% probability level and on FC at the 5% level. Higher PC values were obtained under the CT system (13.07%, against 11.90% and 10.67% for RT and NT, respectively) in all growing seasons. Additionally, the AC was significantly lower in the sample grains under RT (2.38%) and NT (2.43%) than in those from CT (2.56). The FC was higher under NT (15.73%) than RT (13.73) and CT (13.71%). The grain WC was significantly higher under NT (7.57%) than RT (6.79%) and CT (7.0%). The TS significantly affected the surface color parameters of grains, while the L* (lightness) and b* (yellowness) values of grains under CT were higher than in RT and NT.

Morphological characteristics and soybean yields after using different limestone sources

In this study, the growth and productive characteristics of the soybean were investigated in no-till system after using limestone in a tropical soil of the Brazilian Cerrado. The study was conducted in a Typic Hapludox. The sources of limestone came from Piauí miners (C1, C2 and C3) and from a mining company in Ceará (C4) plus a control treatment (without limestone), with four replicates, during the 2013/2014 and 2014/2015 growing seasons, in a randomized block design. The limestone was applied in October 2012, using a gravity distribution. The limestone rate applied was 2.73 Mg ha-1 to raise the soil base saturation to 60%. The final plant stand, relative chlorophyll index, leaf area index, shoot dry matter, photosynthetically active radiation, the efficiency of photosynthetically active radiation, number of stems, pod number per plant, thousand-grain mass and grain yield of the soybean were evaluated. There were significant differences between the sources of limestone, with emphasis on the sources C1 and C4 due to the greater increases in plant growth and soybean grain yield (79% and 90%, respectively, in the 2014/2015 harvest). Soybean yield is correlated to the vegetative and reproductive development of the plant when cultivated in a tropical soil of the Cerrado corrected with limestone.

Seleção multivariada entre e dentro de populações mutantes de feijão

A indução de mutação é estratégia amplamente utilizada nos programas de melhoramento de plantas, e proporciona a criação de variabilidade genética para muitos caracteres de importância agronômica. O objetivo do presente trabalho foi selecionar entre e dentro de populações mutantes de feijão (Phaseolus vulgaris L.) promissoras agronomicamente, nos anos agrícolas 2009/10 e 2010/11, em Lages, SC. Foram avaliadas 40 populações mutantes derivadas de radiação gama de 60Co, nas doses de 100 e 200 Grays. Os genótipos submetidos à mutação induzida foram Pérola, Iapar_81, IPR Uirapuru e IPR Chopim. O delineamento utilizado foi em blocos ao acaso, com três repetições. Foi efetuada análise de variância multivariada e análise discriminante canônica para a exploração das hipóteses. Contrastes multivariados entre as populações mutantes e suas populações originais foram efetuados para testar as hipóteses. A análise de variância multivariada revelou efeito significativo das populações mutantes aninhado aos anos agrícolas. Foi detectada, também, variabilidade dentro das populações mutantes. Estes resultados evidenciam a eficiência do agente mutagênico na criação de variabilidade genética. As populações mutantes selecionadas foram PMP_100 e PMC_200 por apresentarem desempenho promissor em relação aos caracteres diâmetro do caule, massa de mil grãos e rendimentos de grãos. Dentro das populações mutantes selecionadas foi detectada variabilidade genética que pode contribuir para seleção efetiva. As populações PMP_100 e PMC_200 devem ser conduzidas e ainda selecionadas, planta a planta, para obtenção de genótipos promissores.

Plant spatial arrangement affects grain production from branches and stem of soybean cultivars

ABSTRACT Phenotypic plasticity is the ability of plants to undergo changes in morphology and yield components to adapt themselves to distinct environmental conditions. The knowledge on the changes in yield components of branches and stems at varied plant spatial arrangements needs to be updated due to recent changes in soybean production system. Thus, this study aimed to evaluate the yield components of branches and stems, as well as to assess the share of these plant parts in the total grain yield of soybean cultivars with indeterminate growth type, under different spatial arrangements. The experiment was conducted during the growing seasons of 2013/2014 and 2014/2015, under a randomized complete-block design and in a4 × 3 × 2 factorial scheme with three replications. Treatments consisted of four row spacing patterns (narrow rows, twin rows, traditional row spacing, and crossed rows), three seeding rates (150, 300, and 450 thousand viable seeds∙ha–1), and two cultivars (BMX Potencia RR and BRS 359 RR). Narrow rows reduce pods and grains production in branches in relation to the traditional row spacing. The number of grains per pod of stem and of branches is not altered by the changes in plant arrangement. The increase in seeding rate reduces the number of pods per plant of branches in greater magnitude than that of stems. The rise in seeding rate results in larger thousand-grain mass both of branches and of stems, but varies with the growing season.

Efeitos no solo e nas culturas após vinte anos de cultivo convencional e semeadura direta

The aim of this research was to evaluate soil properties and performance of crops after 20 years of cultivation in two management systems in a Humic Cambisol in the south of Brazil. No-tillage (NT) and conventional tillage (CT) were evaluated during the cultivation of maize (Zea mays), bean (Phaseolus vulgaris) and soybean (Glycine max), in two years. Soil samples were collected in three layers at the end of the second year, while the determinations of agronomic traits were carried at the end of each year. NT decreased soil bulk density and increased total porosity, aggregate stability and clay flocculation degree, however it decreased macroporosity at the soil surface. In NT higher accumulations of phosphorus occurred up to 0.05 m, calcium and mag­nesium up to 0.1 m and potassium and organic carbon up to 0.2 m depth compared to CT, and it had a gradient of soil acidification from the surface. Differences in the performance of crops occurred in the second year, being verified in CT a reduction of grain yield of soybean and corn and lower thousand-grain mass of beans compared to NT. Bean and soybean produced low amount of above-ground biomass, independent of soil management, while maize produced high amount and higher biomass in NT than CT.

Physical properties of safflower grains. Part I: Geometric and gravimetric characteristics

ABSTRACT Safflower is an oil crop and its oil can be used for food and industrial purposes. However, there is little information about the physical properties of these grains, which is important for the planning and execution of post-harvest stages. Thus, this study was carried out with the aim of evaluating the effect of drying on the main physical properties of safflower grains. Safflower grains were harvested with an initial moisture content of approximately 0.445 decimal d.b. (dry basis) and subjected to drying in an oven with forced air circulation at 40 °C, until the grains reached a final moisture content of 0.073 ± 0.008 decimal d.b. During the drying, bulk density and true density, porosity, thousand-grain mass, circularity, sphericity, projected and surface area, and surface-volume ratio were measured. Based on these results, it is concluded that all gravimetric and geometrical characteristics of safflower grains were reduced due to the reduction of moisture content, except for the surface-volume ratio.

Efficacy of Insecticide Incorporated Bags against Major Insect Pests of Stored Paddy in Sri Lanka

A study was conducted to evaluate the efficacy of an insecticide (deltamethrin) incorporated bags (Zerofly®) against the insect attacks during paddy storage under Sri Lankan conditions. The study was conducted at Institute of Post Harvest Technology (IPHT), Anuradhapura andat the warehouse of Paddy Marketing Board (PMB), Anuradhapura. Paddy sample in Zerofly® sacks were stacked at both locations and for controls, untreated polysack bags were used. Paddy samples that were collected before storage and at monthly intervals during the storage period were analysed for moisture content, weight loss due to insect damages, Thousand Grain Mass (TGM), germination percentage, Total Milling Yield (TMY) and Head Rice Yield (HRY). Data was analyzed using Analysis of Variance (ANOVA) by Statistical Analysis System (SAS). The moisture content of paddy grains fluctuated between 13.3 – 14.3% during storage period but any significant difference was not observed among bag types. The level of insect damages in control was increased with storage time while the initial level of insect damage of treated bags remained unchanged. The mass loss due to insect damagesof grains was significantly higher (p=0.05) in untreated bags than treated bags. The insect damage was reduced by 3.5-4.a% using Zerofly® bags during paddy storage. In addition, dead insect bodies were found onouter surface of the insecticide incorporated bags but no live or dead insects were found on untreated bag surface during storage. Mainly rice weevil (Sitophils oryza) and lesser grain borer (Rhysoperthadominica) were found in paddy samples of untreated bags and number of insects increased with time. The germination percentage of grains in untreated bags was significantly higher than to thecontrol. It was reduced from 93% to 60-64% and 93% to 82-83% in control and treated bags respectively. During the six months of storage, TGM did not show any significant difference (p=0.05) among different treatments. TMY and HRY resulted significantly (p=0.05) lower values of paddy stored in untreated bags than Zerofly® bags. Use of insecticide incorporated bags can reduce the loss of TMY and HRY of paddy during storage. The study revealed that insecticide treated bags are an appropriate packaging material to protect stored paddy from insect infestations under Sri Lankan conditions.

Foliar application of calcium and boron improves the spike fertily and yield of wheat

Foliar applications of calcium (Ca) and boron (B) could improve the fertilization of flowers and enhance the wheat yield. The effects of foliar spray of Ca and B on plant growth, grain yield and yield components of wheat were investigated in this study. Treatments consisted of 0, 1.8, 3.6, and 7.2 L ha –1 application of chelated fertilizer containing 125 g L –1 of Ca and 6 g L –1 of B ( Omega Cabor II ® ), divided into two spray, the first one at tillering and the second at early bloom. The results revealed that foliar spray of Ca and B did not affect the stem diameter, peduncle length, spike length, hectoliter weight and thousand-grain mass of wheat. Maximum plant height and flag leaf insertion height was recorded with 4.0 L ha –1 application of foliar fertilizer (4% increase over control). The 7.2 L ha –1 application of foliar fertilizer increased significantly the number of spikelets per spike (9%), number of grains per spike (24%), grain mass per spike (28%), spike mass (14%), number of spikes m –2 (32%) and grain yield (30%) compared to the control. Foliar application of Ca and B improves growth, fertilization of flowers and the number of fertile tillers of wheat plants resulting in higher grain yield.

Low contribution of photosynthesis and water-use efficiency to improvement of grain yield in Chinese wheat

The contribution of photosynthesis to yield improvement is important to know in order to determine future breeding strategies. The objectives of this study were to determine the contribution of photosynthesis and water-use efficiency (WUE) to grain yield improvement of facultative wheat (Triticum aestivum L.) cultivars on the Loess Plateau of China released between 1937 and 2004. The grain yield has increased nearly sevenfold during this period. Surprisingly, these increases were not correlated with the rate of photosynthesis per unit of leaf area when the cultivars were planted and managed in the same environment. The increases were also not correlated with transpiration rate, stomatal conductance, or WUE, except at the jointing stage. The total increase in photosynthesis may be due to enlargement of photosynthetic area and photosynthesis duration. The grain yield was positively correlated with the number of grains per unit of area (r = 0.855, P<0.05), harvest index (HI) (r = 0.885, P<0.01), and thousand-grain mass (r = 0.879, P<0.01). The increase in grain yield was limited by the grain number and the grain size (sink-limited) and the yield improvement was attributed to a rise in HI over the last 70 years in a highland agricultural system in China.

Germination of seeds of Avena fatua L. under different storage conditions

Storage conditions have a strong influence on the germination of seeds of &lt;em&gt;Avena fatua&lt;/em&gt; L, especially at variable conditions, the germination decreased. Seeds stored at a constant low temperature maintained the germination capability for 5 years. Under greenhouse conditions, seeds matured and germinated more rapidly comparing to field conditions, but individuals from these seeds were weaker and produced fewer seeds. The higher temperature in the greenhouse accelerated the development and maturing of plants. Field emergence varied depending on seed storage conditions, sample, further reproduction, and weather conditions. It was observed that individual specimens of &lt;em&gt;A. fatua&lt;/em&gt; were able to form ripe seeds with high thousand grain mass (TGM), regardless of the occurrence of fungal diseases. The knowledge of the biology of &lt;em&gt;A. fatua&lt;/em&gt; is very important due to its status as a restricted weed in certified seed of crop plants.

End-use quality characteristics of hermetically stored paddy

Four paddy varieties (Bg 352, Bg 300, Bg 358 and Bg 360) were stored in hermetic IRRI bags and common woven polyethylene bags (polybags) at room temperature either uninfested or infested with rice weevils (Sitophilus oryzae (L.)). After 9 months of storage, samples were tested for insect mortality, gas contents, moisture content (m.c.), thousand grain mass (TGM), porosity, hardness, whiteness, total milled rice yield (TMR), head rice yield (HRY), gelatinization temperature, amylose (AC), crude protein (CP), crude fat, free fatty acid (FFA), thiamine and niacin contents and sensory characteristics. These properties after storage were compared with their initial condition. The oxygen content dropped from 21% to 7% and 13.8% for infested and uninfested IRRI bag samples, respectively. The results showed that m.c., of the IRRI bag samples increased significantly (P < 0.05) by 5% when compared to the initial sample but it increased by 15% in polybag stored samples. After 9 months, dry matter loss (DM) was 65% higher in polybag than IRRI bag samples. Highest DM loss was observed in Bg 300 and the lowest DM loss was observed in Bg 358 and Bg 360. Paddy samples stored in IRRI bags showed reduced whiteness compared to polybag stored samples. Storage in IRRI bags significantly increased (P < 0.05) TMR, HRY, AC and sensory values compared to polybag samples. However, paddy samples stored in polybags significantly increased (P < 0.05) their CP and FFA contents while decreasing sensory values, thiamine and niacin contents. The FFA value of polybag samples was 2.5 times higher than IRRI bag samples. Hermetic storage of dry paddy improved overall paddy quality but different end-use quality parameters were observed in the two paddy grain types of short round (Bg 352 and Bg 300) or intermediate bold (Bg 358 and Bg 360).

Effect of Moisture Content on Some Physical and Mechanical Properties of Sira Bean Grains

Some physical and mechanical properties of sira bean grains were determined as a function of moisture content in the range of 11.36% to 24.53% dry basis (d.b.) to provide information for the design of harvesting, handling, processing, and storage equipment and facilities. The average length, width, and thickness were 6.90 mm, 11.65 mm, and 5.39 mm, respectively, at 11.36% d.b. moisture content. The arithmetic and geometric mean diameters increased 7.01% and 7.67%, respectively, while the sphericity increased 3.07% in the moisture range from 11.36% to 24.53% d.b. Studies on rewetted sira bean grains showed that the thousand-grain mass increased 26.04%, the projected area 26.51%, the true density 10.54%, the porosity from 29.60% to 44.50%, and the terminal velocity 20.96%, while the bulk density decreased from 700.5 to 610.5 kg m-3 with an increase in the moisture content range of 11.36% to 24.53% d.b. The static coefficient of friction of sira bean grains increased linearly for six structural materials, namely, rubber (21.05%), aluminum (19.02%), stainless steel (18.03%), galvanized iron (27.59%), glass (22.38%), and MDF (medium-density fiberboard) (25.08%) as the moisture content increased from 11.36% to 24.53% d.b. The shelling resistance of sira beans decreased as the moisture content increased to 34.07%.