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Notes on the history of wheat stabilisation
1946
Effects of rains on wheat during harvest
1946
Swanson, C. O. (Charles Oscar)
Stem distortion of wheat
1946
Blodgett, E.C. | Schultz, H.K.
A particular type of stem distortion of wheat has been found to be perpetuated from one season to the next by seed of winter wheat. Although this does not definitely preclude the possibility that insects or parasitic organisms are involved, it indicates that the condition may be caused by some genetic factor or possibly by a virus. There is some similarity between the symptoms for stem distortion and those effects from injury by the western wheat aphis. These insects were not observed, however, on the plants at Moscow, and it seems unlikely that any insects or their damage were seed transmitted.
Show more [+] Less [-]Relation of temperature to the expression of resistance in wheats to hessian fly
1946
Cartwright, W.B. | Caldwell, R.M. | Compton, L.E.
The percentage of plants infested and the intensity of infestation by the hessian fly, Phytophaga destructor Say, were studied in seedlings of four resistant and two susceptible varieties of wheat grown in the greenhouse at the two temperature ranges of 60 degrees to 65 degrees and 75 degrees to 80 degrees F. At the higher temperatures the percentages and the intensities of infestation were significantly greater on the resistant spring wheat W38 and its resistant winter-type progeny B36162A13-12. The effects of temperature were similar with the susceptible varieties B42, a spring type, and Wabash, a winter type, but in each case the relative magnitude of the effect was much smaller than for the resistant varieties. From the experiments conducted it was not possible to determine whether the effects of temperature on infestation were due to the response of the host plant alone or to a combined response of both the host plant and the insect. The near immunity of the durum P.I. 94587 was found not to be reduced at the higher temperature. The resistance of a common wheat (42-chromosome) derivative of this durum, however, was greatly affected by temperature. The immutability of the resistance of the durum P.I. 94587 at different temperatures is believed to indicate a fundamentally different resistance in that strain, as contrasted with the resistance of the common-wheat varieties studied.
Show more [+] Less [-]Effect of corn, soybeans, their residues, and a straw mulch on soil aggregation
1946
Stauffer, R.S.
1. A study was made of soil aggregation as affected by growing, corn, growing soybeans, a mulch of wheat straw, corn stalks broken down across the slope after harvest, soybean straw spread on the respective plots after threshing, and season. A comparison was also made of the aggregation in the thin surface layer of soil, about 3/8 inch thick, with that in the 3/8 to 5-inch layer. 2. The thin surface layer of soil, approximately 3/8 inch thick, contained a smaller percentage of aggregates, particularly of the larger sizes, than the 3/8 to 5-inch layer. These results confirm the conclusions of others that the surface soil becomes dispersed, particularly if there is no protective cover on the soil. 3. The mulch of wheat straw definitely favored the formation of the larger aggregates. The soybean straw and the corn stalks remaining on the soil over winter seemed to favor aggregation but did not increase significantly the percentage of aggregates. 4. The soil on the corn plots contained a higher percentage of aggregates larger than 0.50 mm than that of the soybean plots. 5. On the corn plots the percentage of aggregates larger than 0.50 mm increased during the four years the experiment was in progress. On the soybean plots there was a decrease except on those plots receiving a mulch of wheat straw.
Show more [+] Less [-]Distribution of thiamin (Vitamin B1) and fat in wheat grain
1946
L. H. Pulkki | K. Puutula
The chief purpose of the experiments has been to find out the thiamin content of the different parts of wheat grain. Special attention has been paid to the relation of the thiamin and fat content in germ, in the outer bran tissues, and in flours of different grades. On comparing the yeast fermentation method and thiochrome method with each other the former gave 45 to 85 per cent higher values for thiamin than the latter. The results presented in this paper were obtained by using the thiochrome method. All thiamin, as well as crude fat, ash, and fiber contents are given on dry basis. 70 to 80 per cent of the thiamin contained in wheat is concentrated in the germ end of the kernel. In analysis there were obtained the following contents for the germ preparations separated in a special way; ash 5.6 & 5.7 %; thiamin 35.1 & 35.0 μg/g; fat 18.8 & 15.8 % (the corresponding figures of whole kernel; 1.8 & 2.0 %; 3.9 & 3.5 μg/g; and 2.0 & 2.0 %). The thiamin content of the germ preparation was accordingly 9 to 10 times and the fat content 8 to 10 times greater than that on whole kernel so that the relation of the thiamin and fat contents in the germ preparation was about the same as in whole kernel. The content of ash, on the contrary, vas comparatively much lower in germ. The thiamin content of the outer bran tissues of wheat is very low. A small quantity of bran containing thiamin only about a quarter (0.9 μg/g) of the amount contained in whole kernel (3.8 μg/g) was separated with a scouring apparatus of simple construction. It was further possible to separate material about 7 per cent of the weight of grain from its surface without more than 7 per cent decrease in the thiamin content; while the decrease in the fiber content was greater by far (about 40 per cent). The relation crude fat/thiamin is greater in bran tissues than in whole kernel. Analytical data are given of milling products and a series of flours of a commercial mill which was obtained by mixing mill streams in an order according to the ascending ash content. The possibility to control the amount of thiamin in commercial flour and its physiological value on the ground of the ash and fat contents is discussed. On the ground of the fat analysis it is to some extent possible to decide whether the vitamin or mineral substances found in flour has come into it »in a natural way» i.e. as a result of a high rate of extraction, or if a remarkable part of the nutrient in question has been added into it.
Show more [+] Less [-]The development of buffalo grass seed
1946
Harlan, J.R.
1. Various details of the development of buffalo grass seed from the unfertilized ovary to maturity were observed and described. 2. The most striking feature of this development is the green scutellum which forms a broad shield behind the remainder of the embryo and which on maturity covers the entire dorsal surface of the endosperm. 3. Differences between buffalo grass and the wheat seed are listed, including the lack of a cross layer, the thin integuments, the adjacent, basal location of the chalaza and micropyle, and the multicellular suspensor in buffalo grass.
Show more [+] Less [-]Effect of row spacing on the yield of small grain nurse crops
1946
Harper, H.J.
The effect of planting a small grain crop in rows 7 or 14 inches apart on the growth of legume seedlings and yield of grain has been studied at the Oklahoma Agricultural Experiment Station over a period of 16 years. Increasing the distance between rows of small grain from 7 or 8 inches to 14 or 16 inches by closing every other opening in the grain drill will provide a more favorable opportunity for the survival of legume seedlings during normal drought periods. Results of cooperative tests in central and eastern Oklahoma show that the effect of row spacings on yield were quite variable. The average production of grain and straw was slightly lower when drill rows were 14 inches apart and only one-half as much seed was planted as compared with a 7-inch spacing. Spring oats planted over a 10-year period at Stillwater, Okla., have produced as much grain when drilled in 14-inch rows as when planted in 7-inch rows. The average yields were 34.6 and 34.3 bushels, respectively. Michigan winter barley, planted in 14-inch rows at the rate of 1 bushel per acre, has suffered a greater reduction in yield, about 3 bushels net loss, than winter wheat, rye, or spring oats. Very little advantage in the stand of legume seedlings will be secured from wide row spacing of small grain when summer rainfall is abundant and summer temperatures are below average. During many seasons when summer drought is severe, a good stand of sweetclover will be obtained on plots when the small grain is drilled in 14-inch rows, whereas a complete failure will occur on plots where the drill rows are spaced 7 inches apart.
Show more [+] Less [-]Comparação de Proteínas: alimentação das aves I
1946
Torres, A. Di Paravicini
A Seção de Avicultura e Cunicultura da E. S. A. "Luiz de Queiroz", da Univ. de São Paulo, dando inicio a um trabalho de comparação de proteínas na alimentação de franguinhos em crescimento, submeteu quatro lotes de 15 pintos, durante um periodo de 40 dias a quatro rações, cuja base, além de suprimento mineral, era constituida de 50% de fubá de milho amarelo 30% de farelo de trigo. A RI continha mais 10% de farinha de carne de 40% e 10 de farelo de amendoim; em R2, foi o farelo de amendoim substituido por farelo (de algodão; em R3 nao havia farinha de carne, mas 7% de farelo de amendoim, 7 de farelo de coco e 7 de farelo de algodão; em R4 completou-se a ração basal com partes iguais de farinha de carne, farelo de caroço de algodão, de amendoim e de coco. Aparentemente, R4 deu os melhores resultados, mas os dados obtidos, depois de analisados, nao apresentavam significação estatística. | Beginning an experiment on protein comparisons, at the Poultry and Rabbitry Departament of the Esc. Sup. de Agricultura "Luiz de Queiroz", University of S. Paulo, four groups of growing chicks were submitted during 40 days to the following rations: basal part - 50 corn meal and 30 wheat bran, variable part - R1 - 10 tankage and 10 peanut meal, R2 - 10 tankage and 10 cottonseed meal, R3 - 7 peanut meal, 7 cocoanut meal and 7 cottonseed meal, R4 - 5 tankage, 5 peanut, 5 cocoanut and 5 cottenseed meal, R2 and R3 gave results which may be considered as equal and inferior than those obtained with the others, R4 being the best one. The statistical analises showed no significant differences.
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