Grain Yield Of Oats Research Articles

Morphological Changes Associated with Three Cycles of Recurrent Selection for Grain Yield Improvement in Oat1

To assess the potential for improving grain yield via indirect morphological trait selection, the original and third cycle parents from a recurrent selection program for grain yield in oat (Avena sativa L.) were compared. Evaluation was based on hill plots grown in three field environments. This selection increased grain yield 13.5% and total dry matter 15.9%; thus, there was no increase in harvest index. All morphological structures measured increased in size. Grain yield was not closely or consistently related to any individual morphological trait, nor to the photosynthetic area of the flag leaf and panicle. Analysis of allometric relationships (the size of one plant structure relative to another) indicated that the size of morphological structures within a genotype tended to be proportional, but variability in allometric relationships was present. Therefore, selection for altered allometric relationships may be successful, but construction of an ideotype based on certain levels of expression of individual morphological traits, or photosynthetic areas, is not likely to be effective in increasing grain yield.

Selection for grain yield of oats via vegetative growth rates measured at anthesis and maturity

Grain yield of oats can be improved by increasing either vegetative growth rate or harvest index, but these two traits are negatively associated. Currently, harvest index of oats is near an optimum at 45%, so further improvement in grain yield must come from increased vegetative growth rate. In this study, vegetative growth rate was measured at anthesis and at maturity by dividing vegetative dry weight at anthesis and straw yield, respectively, by days to heading. Genotypic correlations between the two estimates of vegetative growth rate ranged from 0.53 to 0.66. When the highest 10% of the lines were selected for the two growth rate measurements, the actual genetic gain in grain yield was 3.5% when vegetative growth at anthesis was used, and a slight decrease occurred when vegetative growth rate at maturity was used. Selection for either growth rate measurement caused associated increases in biological and straw yields and dry weight at anthesis.

Increasing grain yield of oats by independent culling for harvest index and vegetative growth index or unit straw weight

Most variation in grain yield of oats is due to variation in harvest index and vegetative growth index, but the latter traits are negatively associated. Therefore we used independent culling levels to select oat genotypes with high levels of vigor traits and a desirable level of harvest index in an attempts to maximize grain yield. Harvest index and vegetative growth index or harvest index and unit straw weight were selected at various culling levels. Intensive selection for harvest index resulted in high harvest index but no grain yield improvement, because the selected lines had poor vigor. Intensive selection for vegetative growth index or unit straw weight resulted in high biomass but low harvest index.

Direct and indirect selection for grain yield in oats (avena sativa L.)

Direct and indirect selection for increased grain yield were carried out on a population of 678 F2-derived lines of oats. A selection intensity of 10% was used with direct selection (selection for grain yield itself) and with indirect selection using three criteria, harvest index, vegetative growth rate, and the index of harvest index + vegetative growth rate. Expected gains from 1978 evaluations were compared to actual gains measured in 1980. Actual grain yield increases were 4, 8, 7, and 6% from selection via harvest index, vegetative growth rate, grain yield, and harvest index + vegetative growth rate, respectively. Thus, indirect selection via vegetative growth rate gave a greater increase in grain yield than did direct selection. Heritability values computed via components of variance ranged from 0.50 to0.57 for the three traits, harvest index, vegetative growth rate, and grain yield, whereas regression heritabilities ranged from 0.41 to 0.55. Realized heritabilities were 0.33, 1.00 and 0.89 for the three traits, respectively. Selection via all criteria caused significant changes in nearly all agronomic traits except weight per volume. Vegetative growth rate, which gave the greatest gain in grain yield, caused less drastic changes in days to anthesis, plant height, biological yield, and vegetative yield than did direct selection for grain yield.

EFFETS DE DIFFERENTS TAUX DE FUMIER SUR LES POPULATIONS DE MAUVAISES HERBES, LA VERSE ET LE RENDEMENT EN GRAINS DES CEREALES

The effect of four rates (9–36 t/ha) of sheep manure applied in the fall was compared to conventional inorganic fertilization (49 kg of N, 60 kg of P2O5 and 60 kg of K2O/ha) applied at seeding on three species of cereals. Weed populations, lodging and grain yields were recorded on oats (Avena sativa L.), barley (Hordeum vulgare L.) and wheat (Triticum aestivum L.) from 1976 to 1978 on the St-André sandy loam and in 1977 and 1978 on the Kamouraska clay. The manure applied came from sheep fed entirely with hay silage. The various rates of sheep manure had no effect on weed population since no significant difference has been observed between the organic and inorganic fertilization. Lodging did not occur in any of the plots, irrespective of the soil type, during the 3 yr of the experiment. For the two soil types, the grain yields of oats, barley and wheat were usually higher on plots that received 27–36 t/ha of sheep manure than on plots that received inorganic fertilizer. The rates of 9 and 18 t/ha of manure resulted in grain yields significantly lower. An application on all plots of 15 kg/ha of inorganic nitrogen in the spring of 1978 has sensibly increased the grain yield. These results suggest that the fall spreading and the incorporation into the soil of 36 t/ha of sheep manure followed by an application of about 15 kg/ha of inorganic nitrogen in the spring provide a very satisfactory grain yield and do not increase the incidence of lodging and weed infestation.

Contribution of growth rate and harvest index to grain yield of oats (Avena sativa L.) following selfing and outcrossing of M1 plants

Three populations of oats, each with 790 lines, were derived from CI 7555: (a) one (M population) consisted of M2-derived lines obtained from EMS treatment of naked seeds, (b) one (O population) consisted of F2-derived lines from crosses of M1 with check plants, and (c) one (C population) consisted of check lines.

Contributions of Vegetative Growth Rate and Harvest Index to Grain Yield of Progenies from Avena sativa ✕ A. Sterilis Crosses1

The relative importance of growth rate and harvest index in determining grain yield of oats was studied in various backcross generations of all possible matings between two strains of Avena sativa and eight collections of A. sterilis. Eight interspecific matings evaluated in 1972 showed maximum heterosis for growth rate in Bc0 (original cross), whereas the eight tested in 1974 showed maximum heterosis for this trait in Bc3. Pooled correlations for growth rate and harvest index with grain yield were 0.76 and 0.54, respectively. The associations of harvest index and growth rate were nearly equal in Bc0, but with repeated backcrosses the association between growth rate and yield intensified, whereas that between harvest index and yield diminished. Variation for grain yield within backcross.mating combinations was determined almost completely by growth rate and harvest index (R2 from 0.92 to 0.97). An increase of 0.1 g/day/plot (0.09 m2) in growth rate gave the same grain yield improvement (14%) as a 4% increased in harvest index.

The Influence of Source of Photosynthate and Sink Size on Grain Yield in Oats (Avena sativa L.)

The Influence of Source of Photosynthate and Sink Size on Grain Yield in Oats (Avena sativa L.)

Impact of Cereal Leaf Beetle Larvae on Yields of Oats1

The impact of Oulema melanopus (L.) larvae on grain yields of oats was investigated in the field at New Carlisle, Indiana, in 1966 and 1968. A gradient of larval population levels was established by using varying rates of malathion in spray applications. A regression analysis of the data showed that a cereal leaf beetle larva completing development to pupation consumed 20% of the leaf surface of I stem. However, the degree of loss in yield this amount of feeding caused was influenced by the stage of development of the crop. Loss in yield ranged from 2.29 to 4.10 bushels per acre per larva per stem infestation. When infestation occurred in the 2- to 3-inch seedling stage, highest losses per larva per stem occurred. Comparable infestations caused less loss in yield when the crop had attained 6 inches of vigorous growth before it became infested.

Genotypic Differences in Photosynthetic Contributions of Plant Parts to Grain Yield in Oats 1

Genotypic Differences in Photosynthetic Contributions of Plant Parts to Grain Yield in Oats ¹

Fertilization of Sphagnum bogs, on the basis of certain field experiments at Leteensuo

The present investigation is an account of the results from two fertilizing experiments established on Sphagnum bog at the Experimental Station of Leteensuo. The experiments were carried out in 1923 and 1934. The following conclusions can be drawn from the results. Most important in significance among the different nutrients is nitrogen, phosphorus ranging next, and potassium last. Potassium could even cause a reduction in the crop yields. The effect of liming was evident in the form of increased hay crops, whereas the grain yields of oats were reduced by it. Liming has improved the effect of phosphorus particularly in the case of hay. The results also seem to indicate that the relation between potassium and calcium has significance in regard to the reduction of crop yield caused by potassium. Remarkable crop yield increases were obtained by nitrogen fertilizing. The hay crops and the grain and straw crops of oats increased almost linearly with the addition of nitrogen, in the form of calcium nitrate, in quantities up to 90 kg N per hectare. Quantities in excess of this caused hardly any further increase in the crops. The said quantity is suitable for cover manuring of hay meadows, but the most advisable quantity for cereals is thought to be 45—60 kg N per hectare, so that lodging of the crops might be avoided. Nitrogen fertilization does not essentially affect the quality of the grain crops of cereals; on the other hand nitrogen promoted the retention of timothy in the meadow when nitrogen was used in quantities up to 90 kg per hectare. Stable manure increased the crops. This effect was most distinctly evident in the grain and straw crops of oats. The effect of stable manure was still present 15 years after the most recent addition of stable manure.

Yield Components in Oats. III. Their Contribution to the Variety ✕ Location Interaction for Grain Yield1

SynopsisIn five out of cases the variety ✕ location interaction variance was smaller for yield components than for grain yield of oats. This seemed to result from the multiplicative method of interaction of the components.

Mutasuon kalkituskokeiden tuloksia Leteensuolta

Mutasuon kalkituskokeiden tuloksia Leteensuolta

The Effect of Nitrogen Fertilization and Duration of Clipping Period on Forage and Grain Yields of Oats, Wheat, and Rye1

SynopsisHigh nitrogen fertilization was effective in maintaining grain yields of oats and rye clipped to mid‐February. Clipping to March 15 resulted in 75% or more reduction in grain yields of oats, wheat, and rye.