This cross was made to study awn inheritance and to discover, if possible, the number of factors involved. The parents used in the cross were Hard Federation, an awnless variety, and Kota, a fully awned wheat. In F3, all the F2 genotypes were tested by the breeding behavior of F3 families, each from a single F2 plant. Four true-breeding classes were found and five which segregated each in a distinct manner. When the observed proportions of each of these 9 genotypes were studied by the closeness-of-fit method, the two P's were 0.97 and 0.45, both good fits. It seems reasonable to conclude that there is a two-factor difference for awns, independently inherited. The classes were clear-cut and definite when determined by the P's breeding behavior, and as carefully checked in the F4 and the F5 generations.

To put it simply, the nutritive value of a product known experimentally to be a food product is determined by its nitrogenous organic matter, fat and hydrocarbon matter contents, and from which its calorific or energetic value is inferred. For a long time, chemistry has only provided this basic data to the field of physiology, supplemented by the global mineral matter content, or, in other words, the percentage of fixed residue obtained through calcination (not really taken into account). | En ramenant les choses à une très simple expression, la valeur nutritive d'un produit quelconque, reconnu expérimentalement comme alimentaire, est déterminée par sa teneur en matières organiques azotées, en matières grasses et en matières hydrocarbonées, d'où se déduit son pouvoir calorifique ou énergétique. Pendant longtemps, la chimie n'a guère mis au service de la physiologie que ces données sommaires, auxquelles s'ajoutait, sans qu'on y attachât grande importance, l'indication de la teneur globale en matières minérales ou plutôt le pourcentage de résidu fixe obtenu par calcination. [OCR NON CONTRÔLE]

The following conclusions have been obtained from an analysis and discussion of the different factors affecting the nature of soil buffer action: The buffering of soils containing different amounts of the same type of colloid increases with the colloid content. Soils containing the same amount of colloid max, have different buffering properties due to variations in the nature of the colloid. Buffering due to organic matter takes place only in slightly acid, neutral, or alkaline reactions. Extraction of soluble Al2O3, Fe2O3, and SiO2 did not materially affect the buffering of soil colloids. Applications of phosphate equivalent to 3, 5, and 10 tons of superphosphate (16% P2O5) per acre did not impart buffering properties to the soil. The nature of soil buffer action is considered solely, a function of the nature of the colloidal acids in the soil and primarily dependent upon the inorganic colloidal clay acids. Organic colloidal acids are responsible for buffer action above the neutral point. Buffering is due to equilibria between these colloidal acids and their salts as affected by hydrolysis, dissociation, and solubility phenomena. The total buffer capacity of soils is determined by the equation: (...). This equation gives the buffering at various pH values as well as the total buffer capacity.

A soil under permanent pasture conditions and the same soil kept free of vegetation were studied from the point of view of microbiological factors of seasonal nitrate nitrogen accumulation under field conditions, accumulation of nitrate from the soil organic matter and from ammonium sulfate, rate of carbon dioxide evolution, and numbers of micro-organisms. The results can be summarized as follows: The soil growing pasture grasses had an extremely low and almost constant nitrate content. The same soil without growing plants accumulated considerable quantities of nitrate, the amount of which exhibited a seasonal fluctuation which seemed to be correlated with the accumulated rainfall. There is evidence also that part of the autumn rise in soil nitrate may be due to mineralization of nitrogenous microbial complexes. The nitrate accumulation from the soil organic matter was 35% greater in soil from pasture plats than in soil from bare plats. A slightly greater nitrification of ammonium sulfate was found in the bare soil than in the pasture soil. The low nitrate values in the grass soil were not due to a lack of nitrifiable organic matter or of a nitrifying flora. The production of carbon dioxide from the pasture soil was on the average 194% of that from the bare soil. This indicates a much greater microbiological activity in the pasture soil. Significant differences in total numbers of micro-organisms as determined by the plate method were not found. Fungi and actinomyces were more numerous in the pasture than in the bare soil. The B. radiobacter group was twice as numerous in the pasture as in the bare soil.

A yield analysis of three varieties of barley, Pedigree, Velvet, and Spartan, growing in drill plats, was made by taking plants from 50 1-foot sections of drill row located at random from each of two plats of a variety. The plats were approximately 1/24 of an acre in size. The data were reduced to a plant basis. The stands within the sampled sections ranged from 2 to 27 plants per foot. Variation in stand was probably due primarily to the unequal distribution of seed by the drill in addition to other causes which affect seedling survival. Spartan produced an average of 2.34; Wisconsin Pedigree, 1.30; and Velvet, 1.19 heads per plant. This significant varietal difference in average head production per plant was considered to be inherent. Variation in soil fertility was probably not a serious factor, while differences in size of seed and thickness of stand had only slight effect. The rate of yield in bushels per acre was velvet, 46.08; Wisconsin Pedigree, 45.52; and Sparta 42.85. Yield per unit was more closely, associated with the number of heads than with the number of plants per unit area. Average yield per plant depended upon the average number of heads per plant and the average weight of grain produced per head. Average yield of grain per head was Wisconsin Pedigree, 0.99 gram; Velvet, 0.89 gram; and Spartan, 0.57 gram. Average weight of grain produced per head varied with the variety, number of heads per plant, class of tiller, and average kernel weight. In total yield for the entire area studied, Velvet was first, Wisconsin Pedigree second, and Spartan third. The order was the same for total number of plants. Spartan, while superior to the other varieties in average yield per plant, had a smaller rate of yield because of a smaller total number of plants, and for the same reason Wisconsin Pedigree yielded less than Velvet. The yield characteristics of a variety can best be determined by a study of single plants. Information derived from such a study is of value to the plant breeder in choosing varieties for crossing in an attempt to combine all of the desirable plant-yield characters. The analysis showed that if seeded at the same rate (pounds per acre) a small-seeded variety may outyield a large-seeded variety on account of the larger number of plants per unit area rather than because of superior plant-yield characters.