Loss Of Grains Research Articles

Microstructure and normal grain growth in metals and ceramics. Part I. Theory

By extending the theory of Feltham and combining it with the work of Rhines and Craig, a detailed statistical theory of normal grain growth has been constructed. The theory exhibits all four attributes of normal grain growth: uniformity, scaling, stability, and lognormality. A prime new feature of the theory is the division of the grains into topological classes (14 planar, 34 spatial), each with a lognormal distribution of grain sizes. Growth is found to be controlled by the rate of loss of grains from the lowest topological class. Complete solutions are found for the grain growth kinetics of each class, as well as the transfer rates between classes. The latter result is used to explain how the median diameter of those classes in which grains are shrinking still manages to increase in the manner required to keep their number a constant fraction of the total population. A parabolic growth law is found for the median grain size of the whole population as well as the median grain size in each topological class. The growth constant for each class is found to increase approximately as the cube of the planar topological parameter or the square of the spatial topological parameter. The Rhines-Craig structural gradient is shown to be independent of time and hence a basic constant of normal grain growth. Stability is due to a maximum in the grain boundary velocity with increasing grain size. The ratio of the maximum to median grain diameter is found to be e(=2.718). A comparison of the present theory is made with that of Hillert. Possible origins of the lognormality are discussed.

Models and techniques for scheduling farm operations: A comparison

Scheduling of farm operations is formulated as a dynamic programming model (a precise model) and as a linear programming model (a global or relaxed model). The precise model can be solved with the dynamic programming technique at considerable cost, but in this study it is solved with simulation and a heuristic scheduling procedure, aimed at reasonable solutions amongst those feasible. The selection of operations at decision moments is done with an urgency strategy which assigns an urgency to each combination or set of gangs operating simultaneously and searches for the combination with maximum urgency. The urgency is based on the timeliness function of the material processed by a gang. Historical hourly weather data and moisture content data for grain, straw and soil for twelve grain harvest seasons are used to evaluate the urgency strategy. The resulting schedule shows a fair use of workable time. From this subjective criterion it is concluded that the urgency strategy is acceptable. Reordering the workable time within a day results in a significantly lower estimate of variable costs for drying wet grain, overtime of men and timeliness loss of grain, straw in the field and bales. A global or relaxed model with five weekly periods is solved by linear programming. Models with and without nesting of workable time for grain, straw and soil continue the tendency of lower costs found with reordering workable time. These lower costs suggest that the resulting schedule is not executable within the real sequence of workable and unworkable time for materials. Handling tighter constraints for workable time and excluding the time workable only for bale handling results in a cost estimate at the level of the simulation and so perhaps in an executable schedule. On the other hand, the lower cost may suggest that the urgency strategy is a poor heuristic procedure. This is not demonstrated, however, by the use of workable time. The performance of the strategy still has to be tested by finding the optimal strategy.

The frequency of embryogenic pollen grains is not increased by in vitro anther culture in Nicotiana tabacum L.

The numbers of embryogenic (S) grains present in in-situ mature anthers of Nicotiana tabacum L. were compared to the numbers of embryos and plantlets produced in cultured anthers excised at the optimal mitotic stage of development for anther culture. The Feulgen technique of staining embryos caused a considerable loss of grains from cultured anthers but this did not seriously affect the determination of the percentage of embryos present. In no instance did the numbers of embryos produced exceed the maximum number of S grains found, and the distributions of S grain and embryo frequencies in anthers were similar. In rare instances S grains which had undergone the first embryogenic division were observed in situ. The results indicate that all grains capable of embryogenesis are determined during early flower formation and that their number is not increased by in vitro culture.

Fusarium heterosporum . [Descriptions of Fungi and Bacteria

Abstract A description is provided for Fusarium heterosporum [Gibberella gordonii] . Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Various cereals including Hordeum, Zea mays, Triticum and Secale . Other strains isolated from cucurbits, Beta , Dianthus, Musa, Trifolium and Solanum . DISEASE: Head blight of cereals, infected heads often showing complete loss of grain. It is particularly widespread in Africa on the small grains cultivated for food. GEOGRAPHICAL DISTRIBUTION: Widespread throughout Africa south of the Sahara, Australia, Germany, Hungary, New Caledonia, New Guinea, Romania, Sarawak, Sweden, UK, USSR. TRANSMISSION: Soil-borne but whether or not the head blight is a result of systemic infection or aerial infection by spores does not appear to have been investigated. It has been isolated from root rots of spring wheat (53, 2945) and it was found to be seed-borne on Sorghum (50, 2915).

The epidemiology of common root rot in Manitou wheat. IV. Appraisal of biomass and grain yield in naturally infected crops

The effects of common root rot (Cochliobolus sativus) on plant biomass and grain yield in naturally infected Triticum aestivum cultivar Manitou were studied at Matador, Saskatchewan, by sampling plants at intervals from seeding to maturity in 1969, 1970, and 1971. Plants were categorized according to the extent of subcrown internode lesions as clean, slight, moderate, or severe. Dry weights and grain yields of plants in each category were determined. Decreasing mean dry weight per plant at all dates and grain yield per plant were consistently associated with increasing disease severity. Significant differences in biomass and grain yield generally existed between clean and slight, slight and severe, and moderate and severe categories. Very close relationships existed between losses in biomass and grain yield both per plant and per unit area. Overall mean biomass losses at maturity in severe, moderate, and slight plants as compared with clean were 58%, 37%, and 25%, respectively; losses in grain yield were 59%, 38%, and 26%, respectively. Biomass losses per square metre increased steadily with time, in all treatments. Grain yield losses per square metre for 1969, 1970, and 1971 summer-fallow checks were 30, 35, and 30%, respectively; the biomass losses at the final sampling dates were analogous.

Effects of Metopolophium dirhodum on Spring Wheat in the Glasshouse

SUMMARYPot‐grown plants of spring wheat, cultivar Maris Dove, Were subjected, commencing at ear emergence, to different, constant levelsof infestation hy Metopolophium dirhodum (Wlk.) in a glasshouse. Infestation with six aphids per stem over 11 days had no significant effect on yield. Infestations with either six or 50 adult aphids or their equivalents, when maintained until ripening, resulted in lower yields of both grain and straw dry matter. Loss of grain was due to reduction in both 1,000 grain weight and the average number of grains per fiertile spikelet. Harvested dry matter content of leaf blades was unaffected by infestation, but the dry matter, content of stems was reduced in infested plants. In breeding aphid‐resistant cereals for Britain, resistance characters restricting aphid multiplication are most likely to reduce yield losses due to aphid attack.

Estimation of grain loss due to sparrows (passer domesticus) in New Zealand

Abstract Grain removed by house sparrows from standing crops of wheat and barley was estimated by sampling 5 ears at 30 points within a crop; errors can be minimised if the samples are taken just before harvest. Loss of grain averaged about 5%, but was as high as 20% in a few crops; a logarithmic transformation gave a 95% confidence interval for the mean loss to wheat crops of from 2.6% to 8.4%. Some birds flew at least a mile from their nests to feed on grain, which was preferred at the “milky” stage.

Assessment of resistant varieties of maize against Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) in laboratory conditions

Grains of five different maize varieties (MMRI Yellow, Pearl White, Malka-2016, YH-1898 and Sadaf) were evaluated for their comparative resistance to Tribolium castaneum under laboratory conditions (30+2°C and 70+5 R.H). Data of percent mortality were taken after 30, 60 and 90 days. Significantly, the maximum mortality of adults was observed in MMRI Yellow (28.57%, 33.67% and 41.61%) in sound seeds and lowest mortality was noted in Sadaf (14.88, 21.33% and 24.99%) during observation period. The seed germination was highest in MMRI Yellow which was 90% while lowest was noted in Sadaf as 50%. The highest protein contents were recorded in Malka-2016 (12.83% and 11.60%) and lowest in YH-1898 (3.90% and 2.50%) in both sound and cracked seeds. However, maximum fiber contents were observed in Malka-2106 (2.76% and 2.16%), while lowest (0.43% and 0.30%) in YH-1898 for both seed types. Consequently, MMRI Yellow variety was proved to be resistance as compared to other varieties with maximum germination. It can be concluded that resistant varieties of maize could be utilized in breeding program to reduce the post-harvest losses of grains.

Studies on the Lodging of Rice Plant (6)

The 14C-tracer experiments presented here were designed mainly to obtain information about the harmfull effect of lodging upon the carbon dioxide assimilation and upon the translocation of assimilated products in rice plants at the reproductive stage of growth. The effectiveness of the “raising-up taretment”, as a remedial counter-measure against such a physiological damage brought about by lodging, was also discussed.The rice plants were found to be seriously affected in their carbon dioxide assimilation when they were lodged at their milky stage of ripening. Even a mere shading, if associated with lodging, showed an additional reduction in the carbon dioxide assimilation. The upward transloction of assimilated products from the leaves to the grains was to a large extent inhibited, while the down-ward translocation of them was blocked at the broken point of tissue or organ. The assimilated products were observed to accumulate in smaller amount in the grains, but remained in larger amount in the leafy organs, as compared with those of normal plants. Lodging was therefore shown to be a physiological damage to the rice plants, resulting in the loss of grain yield.As for the remedial measure, the raising-up treatment was, howerver, found to be considerably effective in preventing the above-mentioned physiological disturbances, if applied immediately after lodging.

The effect of fertilizers and season on the yield and composition of wheat in southern New South Wales

Twenty two fertilizer experiments with wheat were carried out over a wide range of soil and environmental seasonal conditions in southern N.S. W. The effects of phosphorus and nitrogen fertilizers on the yield and composition of wheat are described. Seasonal environmental effects were examined by comparing the relative response to fertilizers of vegetative growth in the early spring with the final response of the harvested grain. Grain yield response to fertilizers is commonly restricted by seasonal conditions. Overcorrection of the phosphorus or nitrogen deficiencies may cause excessive early vegetative growth which exhausts soil moisture reserves before grain development has been completed. Loss of grain yields through this phenomenon is described locally as haying off. The chief danger in this respect seems to be from excessive nitrogen levels in the soil following a clover pasture. Assessments of economically desirable fertilizer applications on the basis of field experiments can only be based on statistical averages of seasonal conditions in each locality. The trials indicate, however, that the common application rate of superphosphate to wheat is inadequate in this region and should be at least doubled.

Kinetics of pulse-labeling of ribonucleic acid in HeLa cells

HeLa cells have been submitted to short tritiated nucleoside pulses, and their radioactivity has been followed in the nucleus minus nucleolus (N), in the nucleolus (n) and in the cytoplasm (C) after various incubation times in unlabeled media. The independent uptake of these nucleosides into the nucleus minus nucleolus and the nucleolus has been confirmed — and part of this radioactivity is transferred from both these cell parts into the cytoplasm. However, the cytoplasmic gain is greater than the nuclear loss of grains. Cytoplasmic ribosomal RNA is probably formed from precursors synthesized in the nucleus and nucleolus, but it is not known whether this RNA undergoes any rearrangement during its transfer to the cytoplasm. Messenger RNA constitutes probably also an important fraction of the RNA label transferred from the nucleus to the cytoplasm.

Kinetics of pulse-labeling of ribonucleic acid in HeLa cells

Abstract HeLa cells have been submitted to short tritiated nucleoside pulses, and their radioactivity has been followed in the nucleus minus nucleolus (N), in the nucleolus (n) and in the cytoplasm (C) after various incubation times in unlabeled media. The independent uptake of these nucleosides into the nucleus minus nucleolus and the nucleolus has been confirmed — and part of this radioactivity is transferred from both these cell parts into the cytoplasm. However, the cytoplasmic gain is greater than the nuclear loss of grains. Cytoplasmic ribosomal RNA is probably formed from precursors synthesized in the nucleus and nucleolus, but it is not known whether this RNA undergoes any rearrangement during its transfer to the cytoplasm. Messenger RNA constitutes probably also an important fraction of the RNA label transferred from the nucleus to the cytoplasm.

Loss of silver grains from radioautographs stained by gallocyanin-chrome alum.

Radioactive tissue sections covered with the film from Kodak Fine-Grain Autoradiographic Stripping Plate AR. 10 were stained with Ehrlich's hematoxylin or gallocyanin-chrome alum after exposure and photographic processing. Staining with gallocyanin-chrome alum at pH 1.7 and 2.4 dissolved the silver grains completely or almost completely in 1 to. Grains were quite visible after a 3 hr staining at pH 3.4, but a statistical analysis revealed a loss of grains, compared with unstained controls. Grains were also lost in slides immersed in solutions of gallocyanin alone at pH 2.5 for 24 hr but not in solutions of chrome alum alone, nor in some other alums. In sections stained 1 hr with Ehrlich's hematoxylin, the grains were not dissolved.

Effect of Plastic and Elastic Stresses on the Losses And the Domain Configurations of Grain-Oriented 3 Pet Si-Fe

Permanent, plastic elongation of about 0.1 pet is shown almost to double the 60-cycle watt losses of grain oriented 3 pet Si-Fe. Subsequent application of tension in the elastic range is shown to eliminate this loss increase. The domain structures corresponding to these effects have been studied and their interpretation bears out the loss results qualitatively.

A study on the maturity of grain in Sorghum

The importance of sorghum as a major food and fodder crop of India demands it efficient management. In this crop, as in many other cereals the date of flowering is much more definite than ripening. It is desirable to know when exactly the crop becomes fit for harvest, steering clear of immature grains and poor germination on the one hand and loss of grain by leaving the crop too long in the field, on the other. If the date of maturity could be fixed definitely as so many days after flowering the crop could be harvested earlier and the straw would also be secured in a greener and more palatable state. Being an exposed grain, sorghum gets discoloured if any rain is received after the dough stage. This reduces its market value: Moreover, if heavy rains are received at the time the grains are in the 'wax' stage, they are liable to germinate in situ, which means a loss in the yield also. Thus a knowledge of the exact date of maturity would help to prevent an unnecesrary delay in harvest. This paper presents the results of a preliminary study on the ripening of sorghum grain.

Improved Technique for Determination of Densities and Porosities

As a rapid method for routine determination of densities and porosities of rock samples, Gealy's modification of Russell's method is one of the best. An alternative procedure has been developed which eliminates various errors involved in direct, grain, and bulk volume measurements and subsequent porosity calculations. This increases considerably the accuracy of the method. It was found that mercury penetrates the pores of many samples. A protective coating of celluloid obviates this difficulty, and prevents loss of grains. The celluloid coating can be made so thin that errors due to the weight of the coating are negligible. The magnitude of errors due to this coating as well as those due to the method itself has been calculated and is given with data for typical samples.