Milky Grains Research Articles

Leukoencephalomalacia in horses associated with immature corn consumption

ABSTRACT: Horse leukoencephalomalacia (ELEM) is a disease caused by the ingestion of mycotoxins (fumonisins) produced by fungi of the genus Fusarium that infect corn and/or its byproducts. This disease has been described by ingestion of mature corn with humidity above 15% at temperatures below 20°C. The aim of this paper was to report an outbreak of leukoencephalomalacia in horses fed with immature corn. Two horses out of three showed neurological signs approximately seven days after eating immature corn in its reproductive phase (R2, milky grains). Corn was harvested and administered directly to the animals, with no storage. Deaths occurred approximately 24 hours after the onset of clinical signs. Grossly, there were multifocal dark red to brown areas in the white matter of the telencephalon and hyppocampus and thalamus. Histologically, there was edema and hemorrhage in several areas of the telencephalon white matter, which corresponded to dark red to brown areas observed in the macroscopy. There was also foci of malacia with presence of reactive astrocytes with abundant eosinophilic cytoplasm and inflammatory cells. Diffuse capillary wall degeneration and endothelial cell swelling were also observed. Two ppm of fumonisin were detected by immunoaffinity column method (VICAM) in the immature corn sample. The water activity in this cereal, when the grain is still milky, is 0.98 and can predispose it to growth of mycotoxin-producing fungi. In the present case, fumonisin was found in milky grains in the beginning of the reproductive phase (R2), which suggested that even immature corn may be infected by Fusarium spp. and should not be administered to horses.

Gel-free/label-free proteomic analysis of developing rice grains under heat stress

High temperature markedly reduces the yields and quality of rice grains. To identify the mechanisms underlying heat stress-induced responses in rice grains, proteomic technique was used. Developing Khao Dawk Mali 105 rice grains at the milky, dough, and mature stages were treated at 40°C for 3days. Aromatic compounds were decreased in rice grains under heat stress. The protein abundance involved in glycolysis and tricarboxylic acid cycle, including glyceraldehyde 3-phosphate dehydrogenase and citrate synthase, was changed in milky and dough grains after heat treatment; however, none changes in mature grains. The abundance involved in amino acid metabolism was increased in dough grains, but decreased in milky grains. In addition, the abundance involved in starch and sucrose metabolism, such as starch synthase, ADP-glucose pyrophosphorylase, granule-bound starch synthase, and alpha amylase, was decreased in milky grains, but increased in dough grains. A number of redox homeostasis-related proteins, such as ascorbate peroxidase and peroxiredoxin, were increased in developing rice grains treated with heat stress. These results suggest that in response to heat stress, the abundance of numerous proteins involved in redox homeostasis and carbohydrate biosynthetic pathways may play a major role in the development of KDML105 rice grains. Biological significanceYield of Khao Dawk Mali 105 rice, which is an economical aromatic rice, was disrupted by environmental stress. Rice grains developed under heat stress caused loss of aroma compound. To identify the mechanism of heat response in rice grain, gel-free/label-free proteomic technique was used. The abundance of proteins involved in glycolysis and tricarboxylic acid cycle was disrupted by heat stress. High temperature limited starch biosynthesis; however, it enhanced sugar biosynthesis in developing rice grains. Redox homeostasis related proteins were disrupted by heat stress. These results suggest that proteins involved in redox homeostasis and carbohydrate pathway might play a major role in developing grains in Khao Dawk Mali 105 rice under heat stress.

Effects of elevated CO2 associated with maize on multiple generations of the cotton bollworm, Helicoverpa armigera

AbstractUnder elevated environmental carbon dioxide (CO2), leaf chewers tend to compensate for decreased leaf nutritional quality with increased consumption; mortality and development times also increase and cause a reduction in the fitness of leaf chewers. However, the effect of elevated CO2 on multiple successive generations of these and other insects is not well understood. Furthermore, information about the direct effects of increased environmental CO2 on developmental time and consumption of herbivores is lacking. In this paper, we tested the hypothesis that cascade effects of elevated CO2 through plants, rather than the direct effects of elevated CO2, are the main factors decreasing the fitness of cotton bollworm, Helicoverpa armigera Hübner (Lepidoptera: Noctuidae). We used two series of experiments to quantify the growth, development, and consumption of H. armigera fed on an artificial diet or C4 plants (maize) grown under two CO2 levels (ambient vs. double ambient). In the first series of experiments, elevated CO2 had no effect on the population abundance or individual consumption for three successive generations of cotton bollworms fed on an artificial diet. In the second series of experiments, elevated CO2 reduced population abundance of cotton bollworm larvae for two successive generations when they were fed maize milky grains. The specific effects were longer larval duration, lower fecundity, and decreased rm of cotton bollworms. Furthermore, elevated CO2 increased individual consumption when cotton bollworm was fed maize milky grains for two successive generations and decreased the population’s total consumption in the first generation but increased it in the second generation. The results from this study indicate that: (1) The effects of elevated CO2 on three successive generations of cotton bollworm fed on artificial diet were weak, or even non‐existent, and (2) elevated CO2 increased the consumption when cotton bollworm were fed maize. Our study also suggests that the damage inflicted by cotton bollworm on maize (a C4 plant) will be seriously affected by the increases in atmospheric CO2, which is unlike our previous results for spring wheat (a C3 plant).

No effects of elevated CO 2 on the population relationship between cotton bollworm, Helicoverpa armigera Hübner (Lepidoptera: Noctuidae), and its parasitoid, Microplitis mediator Haliday (Hymenoptera: Braconidae)

Estimating the population consumption of an insect population under elevated CO 2 is an important step in understanding the effects of elevated CO 2 on herbivore–crop interactions. Two successive generations of cotton bollworm, Helicoverpa armigera Hübner, were reared on milky grains of spring wheat ( Triticum aestivum L.) grown in open-top chambers under increased carbon dioxide (CO 2) concentration. H. armigera development, wheat consumption, and parasitism by Microplitis mediator Haliday were examined, as were the effects of elevated CO 2 on the wheat itself. We experimentally tested the hypotheses that, by quantifying the population consumption of H. armigera, elevated CO 2 enhanced the pest-control ability of M. mediator again H. armigera. Decreases in protein, total amino acid, and nitrogen (N) content were noted in spring wheat when grown in an elevated-CO 2 environment, as were increases in total non-structure carbohydrates (TNCs) and in the ratio of TNC to N. In the first generation of H. armigera reared under elevated CO 2, no significant changes were observed in population generation time ( T) or in the intrinsic rate of increase ( r m) between CO 2 treatments. However, in the second treatment generation, longer generation time resulted in a lower r m value. Elevated-CO 2 levels caused no significant changes in the H. armigera population's total wheat consumption. The rates of parasitism, cocooning, and emergence by M. mediator were also unaffected, as were its average weight and adult lifespan. As no significant changes in wheat consumption by H. armigera or in the parasitic rate of M. mediator were revealed, the results indicate that the population relationship between H. armigera and M. mediator is unlikely to vary due to future elevated atmospheric CO 2 concentrations.

Response of multiple generations of cotton bollworm Helicoverpa armigera Hübner, feeding on spring wheat, to elevated CO2

Abstract: The growth, development and consumption of three successive generations of cotton bollworm, Helicoverpa armigera (Hübner), reared on milky grains of spring wheat grown under elevated CO2 (double‐ambient vs. ambient) in open‐top chambers (OTCs) were examined. Decreases in protein, total amino acid, water and nitrogen content, and increases in total non‐structure carbohydrates (TNCs) and ratio of TNC : nitrogen were found in wheat milky grains grown under elevated CO2 conditions. Changes in quality of wheat grains affected the growth, development and food utilization of H. armigera. Significantly longer larval lifespan for the third generation and lower pupal weight for all generations were observed in cotton bollworm fed on milky grains of spring wheat grown under elevated CO2 conditions. Bollworm fecundity was significantly decreased for the second and third generations under elevated CO2 levels. The consumption, frass per larva and relative consumption rate significantly increased in elevated CO2 compared with ambient CO2 conditions. However, the potential population consumption was significant reduced by elevated CO2 in the second and third generations. The results of this study indicate that elevated CO2 levels adversely affect grain quality, resulting in consistently increased consumption per larva for a longer period to produce less fecund bollworm through generations, suggesting that net damage of cotton bollworm on wheat will be less under elevated atmospheric CO2 levels because increased consumption is offset by slower development and reduced fecundity.

Effects of elevated CO2 on the foraging behavior of cotton bollworm, Helicoverpa armigera

Effects of elevated CO2 on the foraging behavior of cotton bollworm Helicoverpa armigera Hubner reared on milky grains of spring wheat grown in ambient, 550 αL/L and 750 αL/L CO2 concentration atmospheres in open-top chambers (OTC) were studied. The results indicated that: (i) elevated CO2 significantly affected both the type and amount of food eaten by H. armigera reared on milky grains of ambient CO2-grown wheat were significant higher than those for bollworm larvae reared on wheat grains grown in 550 and 750 αL/L CO2 atmospheres; (ii) when bollworm larvae were reared on mixed milky grains from different CO2-grown wheat (food-choice condition), larval duration increased significantly - pupal weight, adult longevity, and fecundity decreased significantly, comparing with those reared on milky grains of ambient CO2-grown wheat, 550 αL/L CO2-grown wheat and 750 αL/L CO2-grown wheat respectively; (iii) significant decreases in the contents of fructose and gross protein (GP) and significant increases in the contents of glucose, amylose, total saccharides (TSC), TSC: GP ratio, free amino acids and soluble protein in the wheat grains with CO2 rising; (iv) and selected-foraging amount/food-choice index of cotton bollworm H. armigera were significantly positive correlated with the contents of fructose and GP of wheat grains, but they had significantly negative relationships with the contents of glucose, amylose, TSC and TSC: GP ratio of wheat grains.

Immature corn as a source of niacin for rats

The variability in the concentration and biological availability of niacin in was investigated. Plots of both sweet and field were harvested at different stages. In rat growth assays for available niacin, grains harvested at the immature, stage and then dried gave values of 88 and 74 micrograms/g, respectively. These values were in contrast to the low growth assay values of 18 and 16 micrograms/g for grain harvested at maturity, and even higher than the value of approximately 56 micrograms/g obtained for each immature in both the Association of Official Analytical Chemists procedure of chemical analysis and a standard microbiological procedure. However, when the milky grains were precooked at neutral pH, the values from these procedures were higher and agreed with the biological assay results. It is suggested that, during the initial alkaline digestion used for these two procedures, a proportion of the niacin in NAD, the major form of niacin in milky corn, degrades. However, when the materials are first cooked at neutral pH, nicotinamide is released without loss, and the pyridine ring is then stable. The traditional American Indian practice of roasting and drying green corn apparently provided a valuable source of niacin.

Immature Corn as a Source of Niacin for Rats

The variability in the concentration and biological availability of niacin in corn was investigated. Plots of both sweet and field corn were harvested at different stages. In rat growth assays for available niacin, grains harvested at the immature, "milky" stage and then dried gave values of 88 and 74 micrograms/g, respectively. These values were in contrast to the low growth assay values of 18 and 16 micrograms/g for grain harvested at maturity, and even higher than the value of approximately 56 micrograms/g obtained for each immature corn in both the Association of Official Analytical Chemists procedure of chemical analysis and a standard microbiological procedure. However, when the milky grains were precooked at neutral pH, the values from these procedures were higher and agreed with the biological assay results. It is suggested that, during the initial alkaline digestion used for these two procedures, a proportion of the niacin in NAD, the major form of niacin in milky corn, degrades. However, when the materials are first cooked at neutral pH, nicotinamide is released without loss, and the pyridine ring is then stable. The traditional American Indian practice of roasting and drying "green corn" apparently provided a valuable source of niacin.

Conversion of sucrose to starch in the developing Pennisetum typhoides grain

Developing grains of pearl millet (Pennisetum typhoides Burm. S & H cv. PIB 155) were sampled and analyzed for starch and its free‐sugar precursors. The activities of invertase, sucrose‐ADP (UDP) glucosyl transferase and of α‐amylase and β‐amylase in relation to the rate of starch accumulation in the developing grain were assayed. By culturing detached ears, the incorporation of 14C from free sugar precursors to starch was studied. The starch content gradually increased until grain maturity. The rate of starch accumulation was maximum around 12 days after anthesis. Around this period, the activities of sucrose‐ADP(UDP) glucosyl transferase and α‐amylase, β‐amylase were also at a peak. Invertase activity was high during the early period of grain development but gradually declined as the grains matured. In the most actively metabolising milky grains, incorporation of 14C from [14C]‐sugars to starch was maximum in the mid mid‐milky grains. Addition of 20 mM K+ to the culture solution did not affect the incorporation of 14C from supplied sucrose to the free sugar pool and to the starch of the grain, but Mg2+ supply at 20 mM concentration lowered 14C incorporation from exogenous sucrose to grain free sugars, although the utilization of the latter for starch synthesis was enhanced.

Statistical Analysis of the Ripening Process in Paddy Rice : III. Discrimination of the stage of yield forecast from fresh weight of ear

To determine the method for discriminating the stage of yield forecast, the author examined what character of rice may be utilized as an index of the discrimination. The obtained results are as follows. 1) Close relation between the rate of moisture content of ear and grain weight on the ripening stage was found, irrespective of places, years and varieties. Therefore, the ripening process of ear can be discriminated by the former. 2) Furthermore, close relation was found between the rate of moisture content of ear and percentage of milky grains. Therefore, the former can be discriminated by the latter. It was found high correlation between grain yield and fresh weight of ear at the stage when percentage of milky grains bigins to decrease. Frome these results, the stage when percentage of milky grains became 10±3%, seems to be a suitable stag for forecasting yield.