Basal Grain Research Articles

Effect of plastic film mulching on the grain filling and hormonal changes of maize under different irrigation conditions.

Plastic film mulching (PM) is widely utilized for maize production in China. However, the effect of PM on the grain yield of crops has not been established, and the biochemical mechanism underlying the increase or decrease in grain yield under PM is not yet understood. Grain filling markedly affects the grain yield. The objective of this study was to investigate the effects of PM on maize grain filling under different irrigation levels and the relationship of such effects with hormonal changes. In the present study, PM was compared with traditional nonmulching management (TN) under 220 mm, 270 mm and 320 mm irrigation amount, and the grain filling characters of the grains located in various parts of the ear and the hormonal changes in the grains were measured. The results indicated that at 220 mm irrigation, PM significantly increased the grain filling rate of the middle and basal grains and decreased the grain filling rate of the upper grains. At 270 mm irrigation, the PM significantly increased the grain filling rate of the all grains. At 320 mm irrigation, the PM only significantly increased the grain filling rate of the upper grains. The IAA, Z+ZR and ABA content in the grains was positively correlated with the grain weight and grain-filling rates; however, the ETH evolution rate of the grains was negatively correlated with the grain weight and grain-filling rates. These results show that the effect of PM on maize grain filling is related to the irrigation amount and that the grain position on the ear and the grain filling of the upper grains was more sensitive to PM and irrigation than were the other grains. In addition, the PM and irrigation regulated the balance of hormones rather than the content of individual hormones to affect the maize grain filling.

Depth-integrated equations for entraining granular flows in narrow channels

AbstractFlowing over erodible beds, channelized granular avalanches can alter their volume by entraining or detraining basal grains. In detail, entrainment results from a gradual adjustment of stress and velocity profiles over depth, bringing bed material past yield (and vice versa for detrainment). To capture this process, we propose new depth-integrated equations that balance kinetic energy in addition to mass and momentum. The equations require a local granular rheology, assumed viscoplastic, but no extra erosion law. Entrainment rates are instead deduced from the depth-integrated layer dynamics. To check the approach, we obtain solutions for non-equilibrium heap flows, and compare them with experiments conducted in a seesaw channel.

Development of Ultrafine Grained Zircaloy-2 by Room Temperature Cross Rolling

Effect of change in strain path by cross rolling up to a true strain of 1.89 has been studied in the present work. The Zircaloy-2 was subjected to solutionising heat treatment at 800 °C in argon environment for 2 h and subsequently quenched in mercury prior to cross rolling at room temperature. The fragmentation of near basal grains due to change in strain path is evident from the EBSD micrographs. The dislocation density in the crossrolled alloy increases with true strain as calculated from the XRD and EBSD data and it is found to be 2.806453 × 1016/m2. $$ \left\{ {10\bar{1}2} \right\} $$ extension twins are observed initially up to 25% reduction, with the further reduction in thickness, near basal grains are oriented toward the normal direction. These basal grains undergone fragmentation due to changes in strain path upon cross-rolling as observed from KAM and EBSD images. TEM results of the cross-rolled sample confirm the formation of ultrafine and nanograins in the alloy due to orientation of incidental dislocation boundaries in the direction of macroscopic plastic flow and post-annealing treatment of the deformed alloy. A tensile strength of 991 MPa with 7.5% ductility is observed in the 85% cross-rolled alloy. The cross-rolled alloy upon annealing at 400 °C for 30 min improves ductility to 11%.

Impact of Microbial Enzymes on Growth Performance, Micronutrient Digestibility, Tissue Protein Contents and Endogenous Enzyme Activities of Broiler Chickens Fed on Vegetable Protein Diets

A study was conducted to investigate the effects of dietary protein sources and microbial enzyme supplementation on amino acid and mineral digestibility, tissue protein contents and endogenous enzyme activities of broiler chickens. Ross 308 day-old male broiler chicks (n = 160) were assigned randomly to four dietary treatments, each replicated five times, eight chicks per replicate, in a 2 x 2 factorial design. Two basal diets were formulated with soybean (SBM) and canola (CM) meals at a ratio of 75:25, respectively, along with basal grains and fed to the birds as such or supplemented with enzymes from 1 to 35 days. Enzymes had a positive effect on the gross responses (feed intake, body weight and feed conversion ratio) of the broiler chickens at 35 days. However, feed intake was significantly different (p 0.05) body weight and feed conversion ratio (FCR) between 1 and 35 days. Tissue protein contents and endogenous enzyme activities at 21 days (except for maltase) were unaffected by dietary sources and microbial enzyme supplementation. The activity of maltase was higher (p 0.05) on mineral digestibility of broilers over the test period. The digestibility of Cu, Zn and Mg was increased (p<0.05) on CM diet, whereas Ca digestibility was higher on SBM diet at 35 days. It can be concluded that the improved growth of the birds might be a result of increased digestibility of amino acids and increase in feed consumption.

Different annealing behaviours of warm rolled Mg–3Al–1Zn alloy sheets with dynamic recrystallized microstructure and deformation microstructure

The annealing behaviours of Mg–3Al–1Zn magnesium alloy sheets warm rolled at 225°C and 150°C using differential speed rolling, which are mainly characterized by dynamic recrystallized microstructure and deformation microstructure, respectively, were investigated at different annealing stages. Static recrystallization occurs for the sheet rolled at 150°C while only grain growth proceeds for the sheet rolled at 225°C. For the sheet rolled at 225°C, the grain growth of dynamic recrystallized grains eliminates the basal pole inclination in the rolling direction. In contrast, for the sheet rolled at 150°C, the grain growth after static recrystallization retains the basal pole inclination, which is favoured for sheet forming. This difference in texture evolution may be attributed to the dynamic or static recrystallization prior to grain growth, which results in residual dislocation densities for the former and thus leads to the preferential growth of harder oriented basal grains at the centre of (0001) pole figure with lower dislocation densities during annealing.

High speed rolling of Mg–3Al–1Zn alloy: texture and microstructure analysis

High speed rolling (HSR) of 1000 m min−1 was employed to successfully roll AZ31 alloy in one pass with 65% reduction in thickness at 300 and 450°C. The rollability, texture and microstructure after HSR, in comparison with low speed rolling (15 m min−1), improved significantly. It is suggested that the double peak and weaker basal texture obtained after HSR are attributed to the activation of compression and double twins. After annealing, the double peak basal texture is replaced by a single peak one, which may be due to preferential grain growth of basal grains.

Facies clustering in deep-water successions of the Magura zone of the Outer Western Carpathians: implications for interpretation of submarine-fan environments

Statistical analysis of facies clustering in deep-water successions in combination with their facies characteristics has been applied to interpretation of the depositional sub-environment of two selected sedimentary sequences, which expose the Upper Eocene Kýcera Member of the Zlin Formation of the Raca Unit and the Middle Eocene–Lower Oligocene Racibor Formation of the Krynica (Oravska Magura) Unit of the Magura Zone of the Outer Western Carpathians. Clustering patterns of three bed-by-bed variables, namely coarse division thickness, coarse division thickness percentages, and basal grain size were analyzed. Apart from coarse division thickness percentages of the Kýcera Member section, all the datasets passed the Hurst K test and, according to their facies characteristics, revealed the lobe-interlobe motif. Although the employment of this technique confirmed the advantages of its practical utilization in interpretation of submarine fan environments, its widespread application is limited to good exposures where adequate quantity and quality of data is available.

Sedimentological and geochemical evidence for multistage failure of volcanic island landslides: A case study from Icod landslide on north Tenerife, Canary Islands

[1] Volcanic island landslides can pose a significant geohazard through landslide-generated tsunamis. However, a lack of direct observations means that factors influencing tsunamigenic potential of landslides remain poorly constrained. The study of distal turbidites generated from past landslides can provide useful insights into key aspects of the landslide dynamics and emplacement process, such as total event volume and whether landslides occurred as single or multiple events. The northern flank of Tenerife has undergone multiple landslide events, the most recent being the Icod landslide dated at ∼165 ka. The Icod landslide generated a turbidite with a deposit volume of ∼210 km3, covering 355,000 km2of seafloor off northwest Africa. The Icod turbidite architecture displays a stacked sequence of seven normally graded sand and mud intervals (named subunits SBU1–7). Evidence from subunit bulk geochemistry, volume, basal grain size, volcanic glass composition and sand mineralogy, combined with petrophysical and geophysical data, suggests that the subunit facies represents multistage retrogressive failure of the Icod landslide. The basal subunits (SBU1–3) indicate that the first three stages of the landslide had a submarine component, whereas the upper subunits (SBU4–7) originated above sea level. The presence of thin, non-bioturbated, mud intervals between subunit sands suggests a likely time interval of at least several days between each stage of failure. These results have important implications for tsunamigenesis from such landslides, as multistage retrogressive failures, separated by several days and with both a submarine and subaerial component, will have markedly lower tsunamigenic potential than a single-block failure.

Corn or sorghum wet distillers grains with solubles in combination with steam-flaked corn: In vitro fermentation and hydrogen sulfide production1

The effects of wet distillers grains with solubles (WDG) on in vitro rate of gas production, IVDMD, H(2)S production, and VFA were evaluated. Five substrate treatments that were balanced for ether extract content were arranged in a 2 x 2 + 1 factorial. Factors were concentration (15 or 30%; DM basis) and source of WDG (corn or sorghum WDG; CDG and SDG, respectively) plus a 0% WDG control in substrates with steam-flaked corn as the basal grain. Control substrates had greater (P < 0.01) IVDMD and total gas production per gram of substrate DM than WDG-based substrates, and IVDMD was greater (P = 0.03) for CDG than for SDG substrates. Increasing WDG inclusion from 15 to 30% decreased IVDMD and total gas production (P < 0.05), but H(2)S production (micromol/g of fermentable DM) increased (P = 0.01) as inclusion of WDG increased. There were no differences (P > or = 0.10) among treatments in proportions of major VFA, acetate:propionate ratio, and total VFA concentration. These results suggest that including WDG in the substrate decreased IVDMD and gas production, which was particularly evident as WDG increased from 15 to 30% of substrate DM. In addition, CDG seemed to be more digestible than SDG. Hydrogen sulfide production increased with increasing WDG in the substrate, reflecting greater S concentrations in WDG, but in vitro VFA profiles were not affected by WDG concentration or source.

Dried distillers grains with solubles with reduced corn silage levels in beef finishing diets1,2

Two finishing experiments were conducted to evaluate the use of 25% dried corn distillers grains with solubles (DDG) in beef cattle finishing diets by partially replacing a portion of the grain and soybean meal in the control diets. In Exp.1, crossbred heifers (n = 377; BW 378 +/- 4.1 kg) were fed diets consisting of steam-flaked corn (SFC) with a control diet containing 0% DDG and 15% corn silage (CS), 25% DDG and 15% CS, or 25% DDG and 5% CS. Compared with the control treatment, heifers fed DDG and 15% CS had a greater proportion of USDA yield grade 4 and 5 carcasses (P = 0.04; 5.68 vs. 14.12), and smaller LM area (P = 0.04; 86.09 vs. 82.48 cm(2)). In Exp. 2, crossbred heifers (n = 582; BW = 377 +/- 27.09 kg) were fed diets similar to Exp. 1 except dry-rolled corn (DRC) and SFC were compared as the basal grain sources. Treatments included DRC or SFC: with control diets containing 0% DDG and 15% CS, 25% DDG and 15% CS, or 25% DDG and 5% CS. Feeding SFC decreased DMI (P < 0.01), improved G:F (P < 0.01) and final shrunk BW (P = 0.05) compared with DRC. Average USDA yield grade was greater for cattle fed DRC than for those fed SFC (P = 0.02), but calculated yield grade was not different among treatments (P = 0.71). Feeding DDG and 5% CS, regardless of grain source, led to decreased DMI and greater G:F than feeding DDG and 15% CS (P = 0.02). When comparing the control treatments with the diets containing 25% DDG and 15% CS shrunk final BW, ADG, and G:F were decreased (P < or = 0.05); however, carcass-adjusted measurements were not different (P > 0.52). Results indicate that roughage levels can be reduced in feedlot diets containing 25% DDG with no adverse effects on BW gain, feed efficiency, or carcass quality.

Starch Granule Size Distribution in Grains at Different Positions on the Spike of Wheat (Triticum aestivum L.)

AbstractThe present study was carried out to characterize the effects of soil water status, cultivar and grain position on starch granule size distribution. The starch granule size distribution and protein and starch content were determined from three wheat cultivars with reference to the position of the grain on the spike. The results showed that the contents of A‐, B‐ and C‐type starch granules were affected by soil water, genotype and soil water×genotype interaction. Grain position was significant for A‐ and C‐type starch granules. Genotype×grain position and soil water×genotype×grain position interactions only affected C‐type starch granules. Both basal and distal grains on middle spikelets contained three types of starch granules: smaller C‐type granules with diameters &lt;2.0 μm, medium B‐type granules with diameters 2.0–9.8 μm and large A‐type granules with diameters &gt;9.8 μm at maturity. Both percent volume and percent surface area distribution of starch granules in basal grains showed the typical three populations, and those in distal grains exhibited a two‐peak curve. The volume and surface area percentage of C‐type granules and protein content in basal grains were higher than that in distal grains, but those of A, B‐type granules in basal grains were lower than that in distal grains. Compared with irrigation, the percent volume and surface area of B, C‐type starch granules and protein content in basal and distal grains were significantly increased, and those of A‐type were evidently decreased in rainfed condition.

Paleoenvironmental and basin analysis of the late Neoproterozoic (Ediacaran) upper Conception and St. John's groups, west Conception Bay, Newfoundland

The Conception and St. John's groups consist of deep-marine, fine-grained siliciclastic–volcaniclastic rocks with abundant impressions of Ediacaran body fossils. Based on previous tectonic reconstructions, these strata are interpreted to have accumulated during the transition from a fore arc (phase 1, ca. 630–560 Ma) to a strike-slip pull-apart basin (phase 2, ca. 560–540 Ma). The Drook and Mistaken Point formations accumulated during phase 1 and are characterized by tabular, thick- to medium-bedded turbidites (east-southeast paleoflow directions), contourites (southwest paleoflow directions), and volcanic ash beds. The high proportion of each bed consisting of TE (Bouma turbidite division) mudstone, and the lack of correlation between bed thickness and basal grain size, suggest ponding of the turbidity currents. The differences in paleoflow directions and texture between Conception Bay and equivalent units at Mistaken Point imply that the two areas may have been geographically isolated from each other; phase 1 deposition in the study area is inferred to have taken place in the basin-plain portion of a transversely supplied, partially confined sub-basin. This "west Conception sub-basin" is bounded to the east by outcrops of the older Harbour Main Group that we speculate may have been a topographic high separating the sub-basin from the main fore-arc basin located to the present-day east. The Trepassey and Fermeuse formations represent phase 2 and are characterized by tabular thin-bedded turbidites, slump deposits, and volumetrically minor amounts of volcanic ash that accumulated on a southwesterly prograding slope. The regional consistency of lithologies and paleoflow directions throughout the Avalon Peninsula suggest that basin differentiation was minimal at this time.

Changes in the Element Composition of Flours during Maturation of the Winter Wheat Kernel

An underappreciatel field of plant analysis is the change in the nutrient concentration of flours from winter wheat (Triticum aestivum L.) during maturation. The knowledge of these processes is important because breeding solely for higher yield has caused a decrease in the nutrient concentrations important for human nutrition. The difference in nutrient concentration of flours from grains of different spike positions is also an interesting field of plant analysis. The objective of this study was to study these processes to better understand the effect of these factors on flour quality. The concentration and amount of macro (nitrogen, phosphorus, potassium, calcium, magnesium) and micronutrients (copper, manganese, iron, zinc) were determined in the flours of grains of two genotypes from basal, central, and apical grain positions, from the 14th day to the 42th day after anthesis. Genotype and sampling time both affected the concentration of nutrients. The grain position on the head also influenced the N, Ca, K, Mn, P, and S concentrations. The amount of assimilated nutrients in flours increased until the middle of maturity, and then remained around specific values in the case of some elements. We describe the changes in concentrations of these nutrients based on changes in the assimilated mass.

Changes of Quality of Winter Wheat During Maturing

We analysed the flour of two winter wheat varieties to determine the effect of maturity state and grain position in the ear on the element composition of flour. Samples were taken from the 14th to the 42th day of anthesis. Ear samples were cut into three (basal, central and apical) parts, the trashed grains were milled, and the element compositions of the flours were determined.We found that the grain position within the ear has an effect on flour element content. Flours of apical grains had lower nitrogen, phosphorus and sulphur contents than flours of central and basal grains. The nutrients can be divided into two parts, based on the formation of element content during maturation. Nitrogen, sulphur and copper contents changed continuously during maturity, while the P, K, Ca, Mg, Mn, Sr and Zn contents decreased until a specific value and became nearly constant in the second half of maturity. We found that – although the nitrogen concentration of flours changed continuously – the amount of nitrogen in the flours reached a constant value for the second half of maturity.

Microstructure and mechanism of damage tolerance for Ti3SiC2 bulk ceramics

Titanium silicon carbide (Ti3SiC2) is a damage tolerance material that is expected to be used in a number of high temperature applications. In this work, the microstructure and damage tolerance mechanism of Ti3SiC2 was investigated. The result demonstrated that the Ti3SiC2 ceramics prepared by the in-situ hot pressing/solid-liquid reaction process had a dual microstructure, i.e., large laminated grains were distributed within small equiaxial grains. This microstructure is analogous to that of platelets reinforced ceramic matrix composites. The bending test using single-edge-notched-beam specimens revealed that Ti3SiC2 was a damage tolerance material. The damage tolerance mechanisms for Ti3SiC2 are basal plane slip, grain buckling, crack deflection, crack branching, pull-out and delamination of the laminated grains.

Dwarfing genes and cell dimensions in different organs of wheat

A field experiment was conducted under non-limiting water and nutritional conditions with three near-isogenic lines of spring wheat (dwarf, DD; semi-dwarf, SD and standard height, SH) to study the impact of the GA-insensitive alleles Rhtl and Rht2, at the cellular level, on the growth of different vegetative organs and of the pericarp of grains. Cell length and width of blades of different leaves (3, 7 and flag leaf), the flagleaf sheath and the penultimate internode as well as the pericarp of basal grains from central spikelets of the spike were evaluated. With the exception of the flag leaf, dwarfing genes produced a significant reduction in cell length in all the different vegetative organs analysed. There was no effect on the number of cells nor their width. Therefore, in vegetative organs, the effects of these alleles appeared to be exclusively due to a reduction in cell length. It would appear that dwarfing genes act on cell elongation without affecting cell division. The Rht alleles did not modify cell length nor width in the pericarp. Grain weight was different between the lines and these differences were associated with grain volume at the beginning of linear grain growth. Thus, they reduced the size of individual grains by reducing the total number of cells in the pericarp. It appears that Rht alleles reduced the final sizes of vegetative organs (such as internodes and leaves) and of tissues (pericarp) associated with reproductive structures (grains), but the modes of action in these different organs were different.

Dwarfing genes and cell dimensions in different organs of wheat

A field experiment was conducted under non-limiting water and nutritional conditions with three nearisogenic lines of spring wheat (dwarf, DD; semi-dwarf, SD and standard height, SH) to study the impact of the GA-insensitive alleles Rht1 and Rht2, at the cellular level, on the growth of different vegetative organs and of the pericarp of grains. Cell length and width of blades of different leaves (3, 7 and flag leaf), the flagleaf sheath and the penultimate internode as well as the pericarp of basal grains from central spikelets of the spike were evaluated. With the exception of the flag leaf, dwarfing genes produced a significant reduction in cell length in all the different vegetative organs analysed. There was no effect on the number of cells nor their width. Therefore, in vegetative organs, the effects of these alleles appeared to be exclusively due to a reduction in cell length. It would appear that dwarfing genes act on cell elongation without affecting cell division. The Rht alleles did not modify cell length nor width in the pericarp. Grain weight was different between the lines and these differences were associated with grain volume at the beginning of linear grain growth. Thus, they reduced the size of individual grains by reducing the total number of cells in the pericarp. It appears that Rht1 alleles reduced the final sizes of vegetative organs (such as internodes and leaves) and of tissues (pericarp) associated with reproductive structures (grains), but the modes of action in these different organs were different.

Effect of culture media on antheridial configuration in &lt;i&gt;Phytophthora boehmeriae&lt;/i&gt;

The position of the antheridium on the oogonium of Phytophthora boehmeriae was greatly affected by culture media. Agar medium containing lecithin and basal salts and corn grain agar favored the production of paragynous antheridia, while corn meal agar, lima bean agar, vegetable juice agar, and tomato agar were conducive to formation of amphigynous antheridia. The effect of culture media on antheridial configuration was found to be due to nutrient concentration. A high concentration of nutrients in the media was favored the formation of amphigynous antheridia, and a low concentration of nutrients favored paragynous antheridia.Key words: antheridial configuration, oogonium, nutrients, Phytophthora boehmeriae.

Availability and Utilization of Assimilates in Relation to Grain Growth Within the Ear of Wheat

AbstractThe development of grains of different positions in the apical, middle and basal spikelets of wheat var. Kaly‐ansona showed that beyond first two basal grains, the more distal a grain in a spikelet the lower its weight. The distal grains received less assimilates than the proximal grains as revealed from sugar concentration in the grains. The eflficiency of distal grains of kalyansona to synthesize reserves was, however, not inferior than the proximal grains in a spikelet. The depression in grain weight lowards extreme spikelet was lower compared to the depression in weight of individual grams towards a distal position in a spikelet. The study seems to suggest that in order to ensure better grain uniformity while maintaining a higher grain number per ear, the spikelet number per ear should be increased instead of increasing the grain number per spikelet.

Varietal Differences in Grain Filling at the Distal end of Sweet Corn Ear

The bases of varietal differences in the frequency of unfilled grains at the distal end of sweet corn cultivars in relation to : (i) the dry matter production, (ii) partitioning of dry, matter within the ear, and (iii) changes in the florets with emerged silk were investigated.1.Cultivars with delayed silk emergence had the largest total plant dry weight at silking time, the fastest dry matter accumulation rate during grain filling, heaviest ear weight at the harvesting, and the maximaum number of filled grains. A low negative correlation was obtained between the percentage of unfilled grains and dry matter accumulation during grain filling period.2.A positive correlation exists between percentage of the decrease of a single grain weight (SGW) at the distal positions and percentage of the occurrence of unfilled grains on the ear. Ears on cultivars which have significantly lighter SGW at the ear distal end compared to the basal grains had large proportions of unfilled grains.3.A negative correlation exists the percentage of the florets with silk emerging 5 days after the first silk appearance and percentage of the decrease of a SGW at the distal end of the corn ear. The difference in SGW within an ear was small in the cultivars in which silk emerged relatively early, proceeding from the basal to the distal florets.Therefore, the varietal difference in the frequency of unfilled grains are caused, not only by the dry matter accumulation during grain filling, but also by the partitioning of assimilates to the distal grains. Cultivars in which, silk emerged relatively early had : (i) uniform partitioning of dry matter within ear, (ii) greater translocation of assimilate to the distal grains, and (iii) fewer unfilled distal grains.