Effects of Seeding Rates on Harvest Index, Grain Yield, and Biomass Yield in Winter Wheat
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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)

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Yield and partitioning in crops of contrasting cultivars of winter wheat in response to CO2 and temperature in field studies using temperature gradient tunnels

The Journal of Agricultural Science ◽

10.1017/s0021859697005017 ◽

1998 ◽

Vol 130 (1) ◽

pp. 17-27 ◽

Cited By ~ 49

Author(s):

G. R. BATTS ◽

R. H. ELLIS ◽

J. I. L. MORISON ◽

P. N. NKEMKA ◽

P. J. GREGORY ◽

...

Keyword(s):

Temperature Gradient ◽

Winter Wheat ◽

Grain Yield ◽

Biomass Yield ◽

Field Studies ◽

Dry Mass ◽

Seasonal Temperature ◽

Above Ground Biomass ◽

Maximum Benefit ◽

The Impact

Diverse cultivars of winter wheat (Triticum aestivum L.) were grown in the field in 1993/94 and 1994/95 at Reading UK in temperature gradient tunnels at normal atmospheric (c. 370) or elevated CO2 concentration (c. 700 μmol CO2 mol−1 air). In 1993/94, grain yield of cv. Avalon was insensitive to mean temperature (between 8·8 and 10·9°C), while elevated CO2 increased yield by 1·3 t ha−1 (12·6%). In all other cultivars, warming reduced grain yield and CO2 increased grain yield. In 1993/94, in cvs Galahad and Mercia the effects of CO2 and temperature on yield were additive. However, for cv. Hereward in both years and for cv. Soissons in 1994/95, there were negative interactions between the effects of CO2 and temperature on yield: the maximum benefit of doubling CO2 to grain yield, 4·5 and 2·7 t ha−1 (65 and 29%) respectively, occurred at cooler temperatures; there was no benefit from doubling CO2 (i.e. 0%) once the temperature had increased above the seasonal mean by 2·2–2·6°C in cv. Hereward and by 1·3°C in cv. Soissons. The beneficial effect of doubling CO2 on grain yield in cvs Galahad, Hereward, Mercia and Soissons was negated by an increase in mean seasonal temperature of only 0·7–2·0°C. Warming decreased root dry mass at anthesis in 1994/95 while it increased at elevated CO2 (49 and 186%, coolest and warmest regime, respectively). Carbon partitioned to roots declined progressively with warming, while at elevated CO2 there was an average of 56% increase in allocation to roots. The relative impacts of both CO2 and temperature were greater on root dry mass than on either grain yield or total above-ground biomass, while the effects on grain and biomass yield varied considerably between cultivars, suggesting that the impact of rising CO2 and temperature are likely to be dependent on cultivar.

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Irrigation strategy, nitrogen application and fungicide control in winter wheat on a sandy soil. I. Yield, yield components and nitrogen uptake

The Journal of Agricultural Science ◽

10.1017/s0021859699007352 ◽

2000 ◽

Vol 134 (1) ◽

pp. 1-11 ◽

Cited By ~ 45

Author(s):

J. E. OLESEN ◽

J. V. MORTENSEN ◽

L. N. JØRGENSEN ◽

M. N. ANDERSEN

Keyword(s):

Winter Wheat ◽

Grain Yield ◽

Sandy Soil ◽

Harvest Index ◽

First Year ◽

Irrigation Strategy ◽

Nitrogen Rate ◽

Fungicide Application ◽

Second Year ◽

Nitrogen Rates

A three factor experiment with winter wheat (Triticum aestivum L.) was carried out during two years on a coarse sandy soil in Denmark. The factors comprised four irrigation strategies including no irrigation, three nitrogen levels providing 67, 83 or 100% of the recommended nitrogen rate, and two strategies for control of leaf diseases (with and without fungicides). Different varieties were used in the two years, Pepital in the first year and Hussar in the second year. Mildew dominated the trial in the first year, but was almost absent in the second year. Septoria occurred in both years, but most severely in the second year. Irrigation increased grain yield, but there were no significant differences between the three strategies, where irrigation was applied. The effect of irrigation on yield was almost solely via an effect of increased transpiration, whereas water use efficiency and harvest index was unaffected. There was a significant interaction for grain yield between irrigation and nitrogen strategies with higher irrigation effects at higher nitrogen rates. This interaction was absent at high disease levels. Increasing nitrogen rate increased grain yield in the second year, but not in the first year. This was attributed to an increasing mildew incidence with increasing nitrogen rate. Irrigation also increased mildew incidence. This caused significant interactions for grain yield between fungicide application and nitrogen rate and between fungicide application and irrigation strategy. Septoria was also significantly affected by both nitrogen and irrigation strategies, but to a lesser degree and not in a consistent manner. The main effect of disease on grain yield was through a reduction in harvest index and a reduction in grain weight. Increasing nitrogen rates slightly reduced harvest index both on a dry matter and on a nitrogen basis. The interaction effects were smaller than the effects of the main factors, and the effect of changes in irrigation or nitrogen strategy on disease incidence could not substitute for the effective disease control obtained by fungicides. The results do, however, indicate possibilities of improving the efficiency of current decision support systems for both fungicide control by better timing of application and irrigation scheduling by reducing water application.

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Assessment of genetic variability among bread wheat genotypes for agronomic and morphological traits under optimum and stress condition

10.21203/rs.3.rs-401996/v1 ◽

2021 ◽

Author(s):

Tamiru Milkessa Olbana ◽

Firew Mekbib ◽

Wuletaw Tadesse

Keyword(s):

Genetic Variability ◽

Optimum Condition ◽

Grain Yield ◽

Bread Wheat ◽

Harvest Index ◽

Water Regime ◽

Stress Condition ◽

Biomass Yield ◽

Genetic Advance ◽

Days To Maturity

Abstract Background Bread wheat is one of the most important cereal crops produced in almost all agro-ecologies of Ethiopia. Assessment of genetic variability in crop species is one of the major activities of plant breeding which helps to design breeding methods for further evaluation to meet the diversified goals. Methods The experiment was laid out in 8x8 simple lattice design under both optimum and stress conditions at middle Awash during 2019/20 growing season. Water stressed treatment was imposed by withholding three irrigation from 50% flowering up to physiological maturity. In the non-stressed water regime, plants were watered at every 10 days interval using furrow irrigation method. In order to avoid water leakage between treatments, the non-stressed water regime plots were established four meters away from the water stressed regime plots. Results Analysis of variance revealed highly significant (p ≤ 0.01) variation for all studied traits under both conditions. The variation observed for grain yield varied from 2.30-6.0 t ha− 1 and 1.01–4.36 t ha− 1 under optimum and stress conditions respectively. Genotypic and phenotypic coefficient of variation ranged from 3.88(days to maturity) to 20.84% (grain yield) and 4.76(days to maturity) to 24.73% (fertile tiller plant− 1) under optimum condition respectively. Under stress condition GCV and PCV ranged from 4.30(days to maturity) to 18.41% (fertile tiller plant− 1) and 5.19 (days to maturity) to 22.27% (fertile tiller plant− 1) respectively. Broad sense heritability and genetic advance as a percentage of mean ranged from 43(spike length) to 89% (biomass yield) and 6.51(days to maturity) to 40.33% (grain yield) under optimum condition respectively, whereas under stress condition it ranged from 23.40 (harvest index) to 86.1% (days to heading) and 5.69% (harvest index) to 33.34% (biomass yield) respectively. High heritability coupled with high genetic advance as a percentage of mean was recorded for biomass yield and grain yield under optimum condition, whereas for biomass yield and fertile tiller plant− 1under stress condition. Conclusions According to the mean performance of genotypes G3, G24, G26, G24 and G45 had yield advantage over checks under both conditions. Generally, the variation observed among the tested genotypes confirmed the possibility of improvement through selection and hybridization for the study area.

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Dry matter, harvest index, grain yield and water use efficiency as affected by water supply in winter wheat

Irrigation Science ◽

10.1007/s00271-008-0131-2 ◽

2008 ◽

Vol 27 (1) ◽

pp. 1-10 ◽

Cited By ~ 130

Author(s):

Xiying Zhang ◽

Suying Chen ◽

Hongyong Sun ◽

Dong Pei ◽

Yanmei Wang

Keyword(s):

Winter Wheat ◽

Water Supply ◽

Grain Yield ◽

Water Use Efficiency ◽

Water Use ◽

Harvest Index ◽

Dry Matter ◽

Use Efficiency

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Herbicide-Grazing Interactions in Cheat (Bromus secalinus)–Infested Winter Wheat (Triticum aestivum)1

Weed Science ◽

10.1017/s0043174500051432 ◽

1990 ◽

Vol 38 (6) ◽

pp. 532-535 ◽

Cited By ~ 2

Author(s):

Jeffrey A. Koscelny ◽

Thomas F. Peeper

Keyword(s):

Triticum Aestivum ◽

Winter Wheat ◽

Grain Yield ◽

Yield Components ◽

Harvest Index ◽

Field Experiments ◽

Wheat Yield ◽

Wheat Grain ◽

Bromus Secalinus ◽

Herbicide Treatments

Field experiments were conducted to determine the interaction of grazing and herbicide treatments on cheat control and biomass, wheat biomass, wheat grain yield, and wheat yield components. Ethyl-metribuzin at 1120 g ai ha−1and metribuzin at 420 g ai ha−1reduced cheat biomass 91 to 99 and 97 to 98%, respectively. Grazing had no effect on herbicide efficacy. Grazing increased cheat biomass in the check by 24% at only one location but did not affect total wheat plus cheat biomass. With one exception, controlled cheat was replaced by wheat on a 1:1 biomass basis when herbicides caused no crop injury. All herbicide treatments increased grain yield, but grazing did not alter yield. At two locations, increased heads m−2and spikelets/head accounted for most of the grain yield increases, but at one location seeds/spikelet and weight/seed were also increased. Harvest index was unaffected.

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Effect of phosphogypsum on the fertility of chernozem and productivity of oil flax and winter wheat

PROCEEDINGS OF V INTERNATIONAL SCIENTIFIC CONFERENCE “CURRENT STATE, PROBLEMS AND PROSPECTS OF THE DEVELOPMENT OF AGRARIAN SCIENCE” ◽

10.33952/2542-0720-2020-5-9-10-1 ◽

2020 ◽

Author(s):

N.I. Akanova ◽

◽

M.M. Vizirskaya ◽

L.P. Beltyukov ◽

Keyword(s):

Winter Wheat ◽

Grain Yield ◽

Harvest Index ◽

Wheat Grain ◽

Yield Increase ◽

Control Variant ◽

Flax Seeds

Introduction of 5.0 t/ha of phosphogypsum contributed to the receipt of 1.69 t/ha of oil flax seeds; yield increase was 0.36 tons per hectare or 27%. The content and collection of oil also reliably increased. Winter wheat grain yield in the variant with phosphogypsum was 5.48 tons per hectare; yield increase, in this case, reached 0.74 tons per hectare or 15.6%. Harvest index (HI) of winter wheat in the trial fields with phosphogypsum was 50.0%; the same in the control variant (without phosphogypsum) – 38.0%.

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Growth regulator on oat yield indicators

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v21n12p828-833 ◽

2017 ◽

Vol 21 (12) ◽

pp. 828-833

Author(s):

Dionatan K. Krysczun ◽

José A. G. da Silva ◽

Anderson Marolli ◽

Ana P. B. Trautmann ◽

Alessandro D. Lucio ◽

...

Keyword(s):

Grain Yield ◽

Growth Regulator ◽

Harvest Index ◽

Biomass Yield ◽

N Fertilization ◽

The Other ◽

Optimum Dose ◽

Quadratic Trend ◽

Very High ◽

The Ideal

ABSTRACT Growth regulator in oat can reduce lodging with effects on yield indicators. The objective of the study is to define the optimum dose of growth regulator to reduce lodging in oats under different conditions of nitrogen (N) fertilization (reduced, high and very high) and the effects on yield indicators in the succession systems. In each succession system (soybean/oats and corn/oats), two experiments were conducted, one to quantify biomass yield and the other to estimate grain yield and lodging. In the four experiments, the design was randomized blocks with four replicates in 3 x 4 factorial scheme, for N-fertilizer doses (30, 90 and 150 kg ha-1) and growth regulator doses (0, 200, 400 and 600 mL ha-1), respectively. Growth regulator reduces lodging in oat plants, with the ideal doses of 500 mL ha-1 in the soybean/oat system and 400 mL ha-1 in the corn/oat system, regardless of the reduced, high and very high N doses. There is a linear reduction of biological and straw yields, and a quadratic trend in the expression of grain yield and harvest index as a function of the growth regulator doses, regardless of succession systems (soybean/oats and corn/oats).

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ZNAČAJ PREDUSEVA ZA PRODUKTIVNOST KUKURUZA

Zbornik radova ◽

10.46793/sbt26.085s ◽

2021 ◽

Author(s):

Milena Simic ◽

◽

Vesna Dragičevic ◽

Željko Dolijanovic ◽

Milan Brankov ◽

...

Keyword(s):

Winter Wheat ◽

Grain Yield ◽

Crop Rotation ◽

Harvest Index ◽

Soil Tillage ◽

Rotation System ◽

Reduced Frequency ◽

Crop Rotation System ◽

Long Term Studies

The advantages of the three- and four-crop rotations in relation to the two- crop rotation are reduced frequency of soil tillage, and thus savings in energy sources, lower intake of mineral nitrogen fertilisers and the amount of applied herbicides. The aim of the present study was to indicate the importance of a proper alternation of crops in the three-crop rotation system and to compare the advantages of cultivation of maize after winter wheat or soybean in terms of reducing weediness, formation of the harvest index and grain yield. Results of long-term studies have shown that the crop sequence significantly contributed to the decrease in fresh biomass of weed and the increase in the harvest index and grain yield in the maize-winter wheat-soybean rotation in relation to the maize-soybean-winter wheat rotation.

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Interrelationships between stem and ear development in winter wheat: the effects of a Norin 10 dwarfing gene, Gai/Rht2

The Journal of Agricultural Science ◽

10.1017/s0021859600040806 ◽

1981 ◽

Vol 97 (2) ◽

pp. 373-381 ◽

Cited By ~ 96

Author(s):

I. R. Brooking ◽

E. J. M. Kirby

Keyword(s):

Winter Wheat ◽

Grain Yield ◽

Shoot Apex ◽

Harvest Index ◽

Dry Matter ◽

Assimilate Partitioning ◽

Dry Matter Partitioning ◽

Dwarfing Gene ◽

Ear Development ◽

Per Se

SummaryA field and a glasshouse experiment were carried out to assess in winter wheat genotypes the interrelationships between stem and ear development, and to relate these to number of grains and yield. Capelle-Desprez (gai/rht2) and Hobbit ‘s’ (Gai/Rht2) were used together with four F4 lines from the cross between them. Two of the lines were homozygous for gai/rht2 and two lines homozygous for Gai/Rht2. Within each pair of homozygous lines there was a contrast between a tall and a short genotype.There were no consistent differences in shoot apex morphogenesis between the genotypes, and, in general, similar numbers of spikelets and floret primordia were initiated in all genotypes. This contrasts with the hypothesis that genotypes based on Norin 10 (Gai/Rht2) have a fundamentally different pattern of ear morphogenesis. The main differences between genotypes were in dry-matter partitioning to stem and ear prior to anthesis and these were associated more consistently with the dwarfing gene than with height per se. Gai/Rht2 genotypes partitioned more dry matter to the ear during its development and less to the stem and this was reflected in greater ear weight at anthesis, more fertile florets and grains per spikelet, a higher harvest index and higher grain yield than the gai/rht2 genotypes. Although similar numbers of floret primordia were initiated in all genotypes, assimilate partitioning during development determined the proportion which developed into fertile florets at anthesis.

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