Intraspecific competition in oat varieties selected for grain yield and milling

2018 ◽  
Vol 69 (7) ◽  
pp. 673 ◽  
Author(s):  
Victor O. Sadras ◽  
M. Mahadevan ◽  
Pamela K. Zwer
Keyword(s):  
Grain Yield ◽  
Intraspecific Competition ◽  
Harvest Index ◽  
Competitive Ability ◽  
High Yield ◽  
Yield Response ◽  
Index Number ◽  
Environment Interaction ◽  
Grain Number ◽  
Panicle Number

Oats likely emerged as part of the weedy grass assemblage in early wheat and barley crops. Some Avena species, such as A. fatua and A. sterilis, evolved into aggressive weeds, and the high interspecific competitive ability of cultivated oats (A. sativa) is valued agronomically to facilitate weed control in rotations. We tested the hypothesis, verified in many crops, that high yield of oats is related to low intraspecific competitive ability. Ten contemporary oat varieties, selected for grain yield and milling attributes, where grown in three environments. Response to competition was calculated as 100 × (Yb – Yc)/Yc, where Y is yield measured in border (b) and centre (c) rows. The same definition was used to calculate response to competition of yield components (biomass, harvest index, grain number, grain weight) and the components of grain number (panicle number and grains per panicle). Yield response to competition was affected by all three sources of variation, i.e. environment, variety and variety × environment interaction. The interaction demonstrates the plasticity of yield response to intraspecific competition; for example, the response to competition of variety Mortlock varied from 9% to 71% among environments. This plasticity in yield response to competition was partially related to variety-dependent responses to competition for biomass and harvest index, number of panicles and number of grains per panicle. We did not find the expected negative association between yield and variety-dependent response to competition. We discuss how this lack of correlation could relate to sampling issues, i.e. a limitation in the range of environments and varieties explored in this study, or reflect a legitimate feature of oat crops arising from early and contemporary selective pressures.

scholarly journals Canaryseed (Phalaris canariensis L.) accessions from nineteen countries show useful genetic variation for agronomic traits

2011 ◽  
Vol 91 (1) ◽  
pp. 37-48 ◽  
Author(s):  
M. Cogliatti ◽  
F. Bongiorno ◽  
H. Dalla Valle ◽  
W J Rogers
Keyword(s):  
Genetic Variation ◽  
Grain Yield ◽  
Harvest Index ◽  
Agronomic Traits ◽  
Grain Weight ◽  
Environment Interaction ◽  
Grain Number ◽  
Harvest Maturity ◽  
Phalaris Canariensis ◽  
Late Sowing

Fifty-seven accessions of canaryseed (47 populations and 10 cultivars) from 19 countries were evaluated for agronomic traits in four field trials sown over 3 yr in the province of Buenos Aires, Argentina. Genetic variation was found for all traits scored: grain yield and its components (grain weight, grain number per square meter, grain number per head and head number per square meter), harvest index, percent lodging, and phenological characters (emergence to heading, emergence to harvest maturity and heading to harvest maturity). Although genotype × environment interaction was observed for all traits, the additive differences between accessions were sufficient to enable promising breeding materials to be identified. Accessions superior in performance to the local Argentinean population, which in general gave values close to the overall mean of the accessions evaluated, were identified. For example, a population of Moroccan origin gave good yield associated with elevated values of the highly heritable character grain weight, rather than with the more commonly observed grain number per square meter. This population was also of relatively short stature and resistant to lodging, and, although it performed best when sown within the normal sowing date, tolerated late sowing fairly well. Other accessions were also observed with high grain weight, a useful characteristic in itself, since large grains are desirable from a quality point of view. Regarding phenology, the accessions showed a range of 160 degree days (8 calendar days in our conditions) in maturity, which, while not large in magnitude, may be of some utility in crop rotation management. Some accessions were well adapted to late sowing. Grain yield in general was strongly correlated with grain number per square meter. Principal components analysis (PCA) carried out for all characteristics provided indications of accessions combining useful characteristics and identified three components that explained approximately 70% of the phenotypic variation. Furthermore, a second PCA plus regression showed that approximately 60% of the variation in grain yield could be explained by a component associated with harvest index and grain number per square meter. Pointers were provided to possible future breeding targets.Key words: Phalaris canariensis, canaryseed, accessions, yield, phenology, genetics, breeding

scholarly journals Canaryseed (Phalaris canariensis L.) accessions from nineteen countries show useful genetic variation for agronomic traits

2011 ◽  
Vol 91 (1) ◽  
pp. 37-48 ◽  
Author(s):  
M. Cogliatti ◽  
F. Bongiorno ◽  
H. Dalla Valle ◽  
W. J. Rogers
Keyword(s):  
Genetic Variation ◽  
Grain Yield ◽  
Harvest Index ◽  
Agronomic Traits ◽  
Grain Weight ◽  
Environment Interaction ◽  
Grain Number ◽  
Harvest Maturity ◽  
Phalaris Canariensis ◽  
Late Sowing

Cogliatti, M., Bongiorno, F., Dalla Valle, H. and Rogers, W. J. 2011. Canaryseed (Phalaris canariensis L.) accessions from nineteen countries show useful genetic variation for agronomic traits. Can. J. Plant Sci. 91: 37–48. Fifty-seven accessions of canaryseed (47 populations and 10 cultivars) from 19 countries were evaluated for agronomic traits in four field trials sown over 3 yr in the province of Buenos Aires, Argentina. Genetic variation was found for all traits scored: grain yield and its components (grain weight, grain number per square meter, grain number per head and head number per square meter), harvest index, percent lodging, and phenological characters (emergence to heading, emergence to harvest maturity and heading to harvest maturity). Although genotype×environment interaction was observed for all traits, the additive differences between accessions were sufficient to enable promising breeding materials to be identified. Accessions superior in performance to the local Argentinean population, which in general gave values close to the overall mean of the accessions evaluated, were identified. For example, a population of Moroccan origin gave good yield associated with elevated values of the highly heritable character grain weight, rather than with the more commonly observed grain number per square meter. This population was also of relatively short stature and resistant to lodging, and, although it performed best when sown within the normal sowing date, tolerated late sowing fairly well. Other accessions were also observed with high grain weight, a useful characteristic in itself, since large grains are desirable from a quality point of view. Regarding phenology, the accessions showed a range of 160 degree days (8 calendar days in our conditions) in maturity, which, while not large in magnitude, may be of some utility in crop rotation management. Some accessions were well adapted to late sowing. Grain yield in general was strongly correlated with grain number per square meter. Principal components analysis (PCA) carried out for all characteristics provided indications of accessions combining useful characteristics and identified three components that explained approximately 70% of the phenotypic variation. Furthermore, a second PCA plus regression showed that approximately 60% of the variation in grain yield could be explained by a component associated with harvest index and grain number per square meter. Pointers were provided to possible future breeding targets.

Post-anthesis sink size in a high-yielding dwarf wheat: yield response to grain number

1977 ◽  
Vol 28 (2) ◽  
pp. 165 ◽  
Author(s):  
RA Fischer ◽  
I Aguilar ◽  
DR Laing
Keyword(s):  
Grain Yield ◽  
Wheat Yield ◽  
Kernel Weight ◽  
Yield Response ◽  
High Fertility ◽  
Grain Number ◽  
Wide Range ◽  
Carbon Dioxide Fertilization ◽  
Sink Size ◽  
The One

Experiments to study the effect of grain number per sq metre on kernel weight and grain yield in a high-yielding dwarf spring wheat (Triticum aestivum cv. Yecora 70) were conducted in three seasons (1971–1973) under high-fertility irrigated conditions in north-western Mexico. Crop thinning, shading and carbon dioxide fertilization (reported elsewhere), and crowding treatments, all carried out at or before anthesis, led to a wide range in grain numbers (4000 to 34,000/m2). Results indicated the response of grain yield to changing sink size (grains per sq metre), with the post-anthesis environment identical for all crops each year, and with all but the thinner crops intercepting most of the post-anthesis solar radiation. Kernel weight fell linearly with increase in grain number over the whole range of grain numbers studied, but the rate of fall varied with the season. Grain yield, however, increased, reaching a maximum at grain numbers well above those of crops grown with optimal agronomic management but without manipulation. It was concluded that the grain yield in normal crops was limited by both sink and post-anthesis source. There was some doubt, however, as to the interpretation of results from crowded crops, because of likely artificial increases in crop respiration on the one hand, and on the other, in labile carbohydrate reserves in the crops at anthesis. Also deterioration in grain plumpness (hectolitre weight) complicates the simple inference that further gains in yield can come from increased grain numbers alone.

scholarly journals Evaluating Genotype × Environment Interactions of Yield Traits and Adaptability in Rice Cultivars Grown under Temperate, Subtropical and Tropical Environments

Agriculture ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 558
Author(s):  
Xing Huang ◽  
Su Jang ◽  
Backki Kim ◽  
Zhongze Piao ◽  
Edilberto Redona ◽  
...  
Keyword(s):  
Yield Component ◽  
Yield Potential ◽  
High Yield ◽  
Environment Interaction ◽  
Accurate Identification ◽  
Rice Varieties ◽  
Panicle Number ◽  
Tropical Conditions ◽  
Component Traits ◽  
Yield Component Traits

Rice yield is a complex trait that is strongly affected by environment and genotype × environment interaction (GEI) effects. Consideration of GEI in diverse environments facilitates the accurate identification of optimal genotypes with high yield performance, which are adaptable to specific or diverse environments. In this study, multiple environment trials were conducted to evaluate grain yield (GY) and four yield-component traits: panicle length, panicle number, spikelet number per panicle, and thousand-grain weight. Eighty-nine rice varieties were cultivated in temperate, subtropical, and tropical regions for two years. The effects of both GEI (12.4–19.6%) and environment (23.6–69.6%) significantly contributed to the variation of all yield-component traits. In addition, 37.1% of GY variation was explained by GEI, indicating that GY performance was strongly affected by the different environmental conditions. GY performance and genotype stability were evaluated using simultaneous selection indexing, and 19 desirable genotypes were identified with high productivity and broad adaptability across temperate, subtropical, and tropical conditions. These optimal genotypes could be recommended for cultivation and as elite parents for rice breeding programs to improve yield potential and general adaptability to climates.

scholarly journals Patterns of tillering and grain production of winter wheat at a wide range of plant densities.

1978 ◽  
Vol 26 (4) ◽  
pp. 383-398 ◽  
Author(s):  
A. Darwinkel
Keyword(s):  
Winter Wheat ◽  
Grain Yield ◽  
Harvest Index ◽  
Plant Density ◽  
Fold Increase ◽  
Grain Production ◽  
Higher Plant ◽  
Grain Number ◽  
Wide Range ◽  
Plant Densities

The effect of plant density on the growth and productivity of the various ear-bearing stems of winter wheat was studied in detail to obtain information on the pattern of grain production of crops grown under field conditions. Strong compensation effects were measured: a 160-fold increase in plant density (5-800 plants/m2) finally resulted in a 3-fold increase in grain yield (282 to 850 g DM/m2). Max. grain yield was achieved at 100 plants/m2, which corresponded to 430 ears/m2 and to about 19 000 grains/m2. At higher plant densities more ears and more grains were produced, but grain yield remained constant. Tillering/plant was largely favoured by low plant densities because these allowed tiller formation to continue for a longer period and a greater proportion of tillers produced ears. However, at higher plant densities more tillers/unit area were formed and, despite a higher mortality, more ears were produced. The productivity of individual ears, from main stems as well as from tillers, decreased with increasing plant density and with later emergence of shoots. In the range from 5 to 800 plants/m2 grain yield/ear decreased from 2.40 to 1.14 g DM. At 800 plants/m2 nearly all ears originated from main stems, but with decreasing plant density tillers contributed increasingly to the number of ears. At 5 plants/m2, there were 23 ears/plant and grain yield/ear ranged from 4.20 (main stem) to 1.86 g DM (late-formed stems). Grain number/ear was reduced at higher densities and on younger stems, because there were fewer fertile spikelets and fewer grains in these spikelets. At the low density of 5 plants/m2, plants developed solitarily and grain yield/ear was determined by the number of grains/ear as well as by grain wt. Above 400 ears/m2, in this experiment reached at 100 plants/m2 and more, grain yield/ear depended solely on grain number, because the wt. of grains of the various stems were similar. The harvest index showed a max. of about 44% at a moderate plant density; at this density nearly max. grain yield was achieved. At low plant densities the harvest index decreased from 45% in main stems to about 36% in late-formed stems. However, no differences in harvest index existed between the various ear-bearing stems if the number of ears exceeded 400/m2. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Phosphorus and Potassium Fertilizer Application Strategies in Corn–Soybean Rotations

Agronomy ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 195 ◽  
Author(s):  
Timothy Boring ◽  
Kurt Thelen ◽  
James Board ◽  
Jason De Bruin ◽  
Chad Lee ◽  
...  
Keyword(s):  
Grain Yield ◽  
Seed Yield ◽  
Soybean Seed ◽  
Fertilizer Application ◽  
High Yield ◽  
Yield Response ◽  
Soil Test ◽  
Soil Test P ◽  
Corn Grain ◽  
Corn Grain Yield

To determine if current university fertilizer rate and timing recommendations pose a limitation to high-yield corn (Zea mays subsp. mays) and soybean (Glycine max) production, this study compared annual Phosphorous (P) and Potassium (K) fertilizer applications to biennial fertilizer applications, applied at 1× and 2× recommended rates in corn–soybean rotations located in Minnesota (MN), Iowa (IA), Michigan (MI), Arkansas (AR), and Louisiana (LA). At locations with either soil test P or K in the sub-optimal range, corn grain yield was significantly increased with fertilizer application at five of sixteen site years, while soybean seed yield was significantly increased with fertilizer application at one of sixteen site years. At locations with both soil test P and K at optimal or greater levels, corn grain yield was significantly increased at three of thirteen site years and soybean seed yield significantly increased at one of fourteen site years when fertilizer was applied. Site soil test values were generally inversely related to the likelihood of a yield response from fertilizer application, which is consistent with yield response frequencies outlined in state fertilizer recommendations. Soybean yields were similar regardless if fertilizer was applied in the year of crop production or before the preceding corn crop. Based on the results of this work across the US and various yield potentials, it was confirmed that the practice of applying P and K fertilizers at recommended rates biennially prior to first year corn production in a corn–soybean rotation does not appear to be a yield limiting factor in modern, high management production systems.

COMBINING ABILITY ANALYSIS OF DROUGHT TOLERANCE IN WHEAT OVER DIFFERENT WATER REGIMES

2001 ◽  
Vol 48 (4) ◽  
pp. 353-361 ◽  
Author(s):  
E. Farshadfar ◽  
M. Farshadfar ◽  
J. Sutka
Keyword(s):  
Chlorophyll Fluorescence ◽  
Drought Tolerance ◽  
Grain Yield ◽  
Combining Ability ◽  
Relative Water Content ◽  
Harvest Index ◽  
Environment Interaction ◽  
Combining Ability Analysis ◽  
Rainfed Conditions ◽  
Relative Water

To study the properties of some drought tolerance criteria and  agronomic characters in wheat, an eight-parental diallel cross, excluding reciprocals, was grown in a randomized complete block design with three replications under two different water regimes (irrigated and rainfed) for two years in the College of Agriculture at Razi University, Kermanshah, Iran. High broad-sense heritability estimates were observed for harvest index, grain yield, and earliness. Additive gene action was found to be predominant for grain yield, harvest index, relative water content and chlorophyll fluorescence. The results of combining ability analysis revealed that Plainsman was the best general combiner and Plainsman × Kobomugi was the best specific combination for improving drought tolerance. The pooled analysis of variance for combining ability over rainfed conditions reflected that the GCA × environment interaction was not significant for harvest index and chlorophyll fluorescence, and the SCA × environment interaction was  non-significant for relative water content and relative water loss, indicating that genes controlling osmoregulation and the other physiological traits mentioned are not affected in these varieties by different rainfed conditions and hence show static stability.

scholarly journals Assessment of drought resistance in pearl millet (Pennisetum americanum (L.) Leeke). II. Estimation of genotype response to stress

1987 ◽  
Vol 38 (1) ◽  
pp. 49 ◽  
Author(s):  
FR Bidinger ◽  
V Mahalakshmi ◽  
GDP Rao
Keyword(s):  
Drought Stress ◽  
Grain Yield ◽  
Pearl Millet ◽  
Selection Index ◽  
Yield Potential ◽  
Drought Response ◽  
Grain Number ◽  
Component Structure ◽  
Panicle Number ◽  
Response To Stress

The finding that the more than 50% of the variation in grain yield of pearl millet breeding lines in two different drought stress treatments could be attributed to variation in yield potential and time of flowering was used to develop a drought-response index (DRI) based on the residual variation in grain yield, adjusted for experimental error. DRI was positively correlated to measured yield in the drought treatments, and independent of both yield potential and time to flowering. DRI in both midseason and terminal stress treatments was unrelated to yield component structure in the irrigated control treatment, indicating that selection for plant type under non-stressed conditions will not influence drought response. DRI was correlated to both grain number per panicle, and grain yield per panicle in both stress treatments, suggesting differential ability to maintain normal grain number, and/or that grain yield per panicle was an important factor in response to stress. Maintenance of panicle number did not seem to be important for maintenance of yield under drought stress. The correlation of DRI and individual panicle yield was of sufficient magnitude for the latter to serve as a selection index in terminal stress. The use of a DRI as a component of breeding for better adaptation to stress is discussed.

scholarly journals Foliar Potassium Fertilizer Additives Affect Soybean Response and Weed Control with Glyphosate

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Kelly A. Nelson ◽  
Peter P. Motavalli ◽  
William E. Stevens ◽  
John A. Kendig ◽  
David Dunn ◽  
...  
Keyword(s):  
Grain Yield ◽  
Weed Control ◽  
Field Experiments ◽  
Leaf Tissue ◽  
High Yield ◽  
Yield Response ◽  
Soil Test ◽  
Potassium Fertilizer ◽  
K Fertilizer ◽  
Soil Test K

Research in 2004 and 2005 determined the effects of foliar-applied K-fertilizer sources (0-0-62-0 (%N-%P2O5-%K2O-%S), 0-0-25-17, 3-18-18-0, and 5-0-20-13) and additive rates (2.2, 8.8, and 17.6 kg K ha−1) on glyphosate-resistant soybean response and weed control. Field experiments were conducted at Novelty and Portageville with high soil test K and weed populations and at Malden with low soil test K and weed populations. At Novelty, grain yield increased with fertilizer additives at 8.8 kg K ha−1in a high-yield, weed-free environment in 2004, but fertilizer additives reduced yield up to 470 kg ha−1in a low-yield year (2005) depending on the K source and rate. At Portageville, K-fertilizer additives increased grain yield from 700 to 1160 kg ha−1compared to diammonium sulfate, depending on the K source and rate. At Malden, there was no yield response to K sources. Differences in leaf tissue K(P=0.03), S(P=0.03), B(P=0.0001), and Cu(P=0.008)concentrations among treatments were detected 14 d after treatment at Novelty and Malden. Tank mixtures of K-fertilizer additives with glyphosate may provide an option for foliar K applications.

Responsiveness of barley cultivars to nitrogen fertiliser

1997 ◽  
Vol 37 (2) ◽  
pp. 199 ◽  
Author(s):  
G. Fathi ◽  
G. K. McDonald ◽  
R. C. M. Lance
Keyword(s):  
Grain Size ◽  
Grain Yield ◽  
Initial Response ◽  
Kernel Weight ◽  
High Yield ◽  
Malting Quality ◽  
Yield Response ◽  
Genotypic Differences ◽  
Barley Cultivars ◽  
N Rates

Summary. Genotypic differences in responses to nitrogen (N) fertiliser of 6 cultivars of barley (Clipper, Stirling, Weeah, Schooner, Chebec, Skiff) grown at 8 different rates of N were examined in 2 seasons. Measurements of vegetative growth, N content, grain yield, grain protein concentration (GPC) and yield components were taken to identify traits that may contribute to high yield responsiveness. The optimum rates of N for dry matter production at ear emergence (DMee) were greater than 80 kg N/ha for all cultivars and often growth increased up to 105 kg N/ha. Optimum rates of N for grain yield (Nopt) were lower and ranged, on average, from 50 kg N/ha for Clipper to 96 kg N/ha for Chebec. The initial response to N varied from 13–14 kg/kg N in Chebec, Weeah and Schooner, to 36 kg/kg N in Skiff. The Nopt for the semi-dwarf cultivar Skiff was 71 kg N/ha and it tended to show the greatest yield response to N. It produced 19 kernels/g DMee, compared with 15–17 kernels/g DMee in the other cultivars. Unlike most other cultivars, Skiff’s yield was consistently and positively correlated with ears/m2; Stirling was the only other cultivar to show a similar relationship. However, the average kernel weight of Skiff was up to 5 mg lower than that of Clipper, Weeah and Schooner, and varied more than these cultivars between sites, suggesting that consistent grain size may be a problem in this cultivar. By comparison, Clipper and Schooner had lower Nopt (51 kg/ha) and a less variable kernel weight. There were no signs of differences in GPC of the 6 cultivars used here at 3 N-responsive sites. Adding N increased GPC up to the highest rate of N and the responses were generally linear, but GPC at Nopt exceeded the upper limit for malting quality of 11.8% in all cultivars. Average N rates of between 38 kg N/ha (Schooner) and 58 kg N/ha (Skiff) were sufficient to raise GPC above 11.8%. The experiments showed that the N rates for optimum yields varied considerably among cultivars, but applyi1ng rates to achieve maximum yields may cause GPC to exceed the maximum value for malting barley. The use of semi-dwarf cultivars, such as Skiff, which are very responsive to N, can provide some leeway in the choice of N, but there may be a trade-off in quality associated with reduced grain size.

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