Studies on the nitrogenous manuring of winter wheat

1965 ◽  
Vol 65 (3) ◽  
pp. 379-387 ◽  
Author(s):  
J. L. Beveridge ◽  
R. H. Jarvis ◽  
W. J. Ridgman
Keyword(s):  
Environmental Factors ◽  
Winter Wheat ◽  
Grain Yield ◽  
Yield Components ◽  
Field Experiments ◽  
Regression Coefficients ◽  
Partial Regression ◽  
Optimum Time ◽  
The Relationship

1. The problem of when to apply nitrogenous top-dressings to winter wheat has nover been satisfactorily solved. Detailed field and glasshouse experiments on the effects of nitrogenous manuring on the development of wheat plants, and a number of other experiments involving the nitrogenous manuring of wheat are described and the results discussed.2. Partial regression coefficients of grain yield on individual components of yield are used to show how variable is the relationship between grain yield and the components of yield.3. It is concluded that field experiments are never likely to determine an optimum time for nitrogen top-dressing because of the unpredictable relationships between individual yield components and grain yield, and because of the variation in response to nitrogen introduced by seasonal and environmental factors.

scholarly journals Rattail fescue (Vulpia myuros) interference and seed production as affected by sowing time and crop density in winter wheat

Weed Science ◽  
2020 ◽  
pp. 1-10
Author(s):  
Muhammad Javaid Akhter ◽  
Per Kudsk ◽  
Solvejg Kopp Mathiassen ◽  
Bo Melander
Keyword(s):  
Winter Wheat ◽  
Grain Yield ◽  
Seed Production ◽  
Yield Components ◽  
Field Experiments ◽  
Growing Season ◽  
Sowing Time ◽  
Growing Seasons ◽  
Crop Density ◽  
Wide Range

Abstract Field experiments were conducted in the growing seasons of 2017 to 2018 and 2018 to 2019 to evaluate the competitive effects of rattail fescue [Vulpia myuros (L.) C.C. Gmel.] in winter wheat (Triticum aestivum L.) and to assess whether delayed crop sowing and increased crop density influence the emergence, competitiveness, and fecundity of V. myuros. Cumulative emergence showed the potential of V. myuros to emerge rapidly and under a wide range of climatic conditions with no effect of crop density and variable effects of sowing time between the two experiments. Grain yield and yield components were negatively affected by increasing V. myuros density. The relationship between grain yield and V. myuros density was not influenced by sowing time or by crop density, but crop–weed competition was strongly influenced by growing conditions. Due to very different weather conditions, grain yield reductions were lower in the growing season of 2017 to 2018 than in 2018 to 2019, with maximum grain yield losses of 22% and 50% in the two growing seasons, respectively. The yield components, number of crop ears per square meter, and 1,000-kernel weight were affected almost equally, reflecting that V. myuros’s competition with winter wheat occurred both early and late in the growing season. Seed production of V. myuros was suppressed by delaying sowing and increasing crop density. The impacts of delayed sowing and increasing crop density on seed production of V. myuros highlight the potential of these cultural weed control tactics in the long-term management programs of this species.

scholarly journals Date of ear emergence: a factor for notable changing the grain yield of modern winter wheat varieties in different environments of Bulgaria

2021 ◽  
pp. 12-18
Author(s):  
N. Tsenov ◽  
T. Gubatov ◽  
I. Yanchev
Keyword(s):  
Environmental Factors ◽  
Winter Wheat ◽  
Grain Yield ◽  
Environmental Conditions ◽  
Climatic Conditions ◽  
Environment Interaction ◽  
Wheat Varieties ◽  
Emergence Date ◽  
The Relationship ◽  
Winter Wheat Varieties

Abstract. Wheat is a crop with a very long growing season, during which it is subjected to prolonged exposure to many environmental factors. For this reason, the interaction of genotype with conditions is very common for any character of wheat. This study aims to determine whether the grain yield is affected by the change of the ear emergence date (EED) in various environments. In a four-year period, 30 current for national real grain production winter wheat varieties were studied. The EED and grain yield (GY) were studied as quantitative traits within five locations of the country having various soil and climatic conditions. Using several statistical programs, genotype x environment interaction of two traits was analyzed. The emphasis on data analysis was whether changes of traits due to the conditions were related and that the optimization of the ear emergence date could serve as a breeding tool for increasing grain yield. The date of ear emergence and grain yield are traits that are reliably influenced by growing conditions. The change in the date of emergence is mainly of the linear type, while the grain yield shows linear and nonlinear type changes in the same environmental conditions. It was found that the key roles in the change of characteristics are the conditions of the year, with the relatively weakest impact of the genotype on them. There is a positive relationship between the two traits, although their change depends on environmental factors. Although they change to different degrees and in relation to each other, there is a positive correlation between them. The more favorable the environmental conditions, the weaker the relationship between these two traits and vice versa. Under changing climatic conditions, the change in the relationship between the two traits is a signal of the need to create different varieties by date of ear emergence in order to obtain higher yields in the future.

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

Weed Science ◽  
1990 ◽  
Vol 38 (6) ◽  
pp. 532-535 ◽  
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.

The Effect of Different Irrigation Water Levels on Grain Yield, Yield Components and Some Quality Parameters of Silage Maize (Zea mays indentata Sturt.)

2015 ◽  
Vol 43 (1) ◽  
pp. 138-145 ◽  
Author(s):  
Abdullah KARASU ◽  
Hayrettin KUȘCU ◽  
Mehmet ÖZ ◽  
Gamze BAYRAM
Keyword(s):  
Crude Oil ◽  
Grain Yield ◽  
Irrigation Water ◽  
Yield Components ◽  
Crude Protein ◽  
Field Experiments ◽  
Water Levels ◽  
Marmara Region ◽  
Silage Maize ◽  
Irrigation Treatments

This research was conducted in Bursa, Marmara region, Turkey, in order to determine grain yield and some morphological traits which affect the silage maize response to different irrigation water amounts. The grains’ percentage of crude oil and of crude protein were determined. Field experiments were planned following randomized complete block design with three replications and included six irrigation treatments. Irrigation treatments were created as water levels of pan evaporation (Epan) applied via drip irrigation [1.25 × Epan (I125), 1.00 × Epan (I100), 0.75 × Epan (I75), 0.50 × Epan (I50), 0.25 × Epan (I25) and 0 × Epan (I0)]. The highest value of grain yield was found to be 18,268 kg ha-1 in the I125 treatment, which represents excessive water. A quadratic relationship between grain yield and irrigation water applied was obtained. Deficit irrigation decreased grain yield and yield components except the percentage of crude oil and crude protein of grain, but improved the efficient use of irrigation water. Relationships between the grain yield and each yield component were positively significant. The highest correlation coefficient in the research gave the relationship between grain yield and plant height (r=0.957**). The results revealed that 1.25 × Epan and 1.00 × Epantreatments are preferable for higher yield. The results of this study also suggest that if water is limited, the application of 0.75 × Epan can be recommended as optimal treatment, because the best compromise among yield, yield components, quality and irrigation water use efficiency for maize was achieved with this application.

Path Analysis of Red Rice (Oryza sativaL.) Competition by Cultivated Rice

Weed Science ◽  
1992 ◽  
Vol 40 (2) ◽  
pp. 313-319 ◽  
Author(s):  
D. J. Pantone ◽  
J. B. Baker ◽  
P. W. Jordan
Keyword(s):  
Grain Yield ◽  
Path Analysis ◽  
Yield Components ◽  
Field Experiments ◽  
Weight Percent ◽  
Grain Weight ◽  
Research Station ◽  
Direct Effects ◽  
Red Rice ◽  
Cultivated Rice

During 1985 to 1989, a series of field experiments were conducted at the Rice Research Station in Crowley, LA. Path analysis was employed to evaluate the competitive interaction between a weed (red rice) and cultivated rice (Mars). The path analysis quantified direct effects of red rice and Mars rice densities on the yield components (grain weight, percent filled florets, number of florets panicle−1, and panicles plant−1) of red rice and Mars rice. The model illustrated the direct and indirect effects of the yield components on fecundity and grain yield plant−1. The direct effects of Mars and red rice densities on panicles plant−1and florets panicle−1were always negative. In contrast, the effects of density on percent filled florets and grain weight varied from positive to negative and were relatively small, implying that they were determined primarily by density-independent factors. Path analysis indicated that the number of panicles plant−1and florets panicle−1were the most important yield components determining the responses of fecundity and grain yield to competition.

scholarly journals Pre-anthesis development of winter wheat and barley and relationships with grain yield

2018 ◽  
Vol 64 (No. 7) ◽  
pp. 310-316 ◽  
Author(s):  
Mirosavljevic Milan ◽  
Momcolovic Vojislava ◽  
Maksimovic Ivana ◽  
Putnik-Delic Marina ◽  
Pržulj Novo ◽  
...  
Keyword(s):  
Winter Wheat ◽  
Grain Yield ◽  
Sowing Date ◽  
Wheat Cultivars ◽  
Growing Seasons ◽  
Sowing Dates ◽  
Winter Wheat Cultivars ◽  
Leaf Appearance ◽  
Relationship Of ◽  
The Relationship

The aim of this study was to improve understanding of (1) the effect of genotypic and environmental factors on pre-anthesis development and leaf appearance traits of barley and wheat; (2) the relationship of these factors with grain yield, and (3) the differences between these two crops across different environments/sowing dates. Therefore, trials with six two-row winter barley and six winter wheat cultivars were carried out in two successive growing seasons on four sowing dates. Our study showed that the observed traits varied between species, cultivars and sowing dates. In both growing seasons, biomass at anthesis and grain yield declined almost linearly by delaying the sowing date. There was no clear advantage in grain yield of wheat over barley under conditions of later sowing dates. Generally, barley produced more leaf and had shorter phyllochron than wheat. Both wheat and barley showed a similar relationship between grain yield and different pre-anthesis traits.

scholarly journals Variability of grain yield components of some new winter wheat genotypes (Triticum aestivum L.)

2011 ◽  
Vol 48 (No. 5) ◽  
pp. 230-235
Author(s):  
M. Sabo ◽  
M. Bede ◽  
Ž.U. Hardi
Keyword(s):  
Winter Wheat ◽  
Grain Yield ◽  
Yield Components ◽  
Vegetation Period ◽  
Grain Number ◽  
Potential Yield ◽  
High Positive Correlation ◽  
Wheat Genotypes ◽  
Grain Number Per Spike ◽  
Grain Yield Components

Variability of grain yield components of some new winter wheat genotypes (e.g. Lara, Lenta, Kruna, Fiesta, Perla, and one line of AG-45) was examined. The analysis of grain yield components of these genotypes and the line was undertaken in a two-year research (1997/1998 and 1998/1999) at two different locations. Significant differences among genotypes, locations and research years were established. In the first experimental year (1997/1998) there was a high positive correlation between nearly all components of the grain yield. The most significant correlation was found between the grain number per spike and grain yield. In the second experimental year (1998/1999) the components did not show statistically significant correlation with the grain yield. It seems that the grain yield of examined genotypes depended significantly on the grain number per spike, grain mass per spike, and agroecological conditions during the vegetation period, whereby the potential yield was determined by the interaction among genotypes, location and production year. The biggest differences among examined genotypes of winter wheat were found in the stem height and spike length.

506. The importance of machine milking rate in dairy cow management and breeding

1953 ◽  
Vol 20 (2) ◽  
pp. 138-145 ◽  
Author(s):  
F. H. Dodd ◽  
A. S. Foot
Keyword(s):  
Dairy Cows ◽  
Dairy Cow ◽  
Peak Flow ◽  
Milk Composition ◽  
Regression Coefficients ◽  
Partial Regression ◽  
Fat Percentage ◽  
Machine Milking ◽  
Lactation Length ◽  
The Relationship

An analysis has been carried out on the milk yield, milk composition and milking-rate records collected in one herd of dairy cows.It has been shown from the results of eighty-six heifers that for each pound per minute increase in inherent milking rate (i.e. peak flow) the standard lactation yield increases by 419 lb., the maximum daily yield by 0·9 lb., the lactation length by 8 days and the persistency index by 10 days, whilst the lactation solids-not-fat percentage decreases by 0·03 and the fat percentage by 0·04. All except the last coefficient were significant, although it was also shown that the relationship with solids-not-fat percentage was due to an interaction. Similarly, by the calculation of partial regression coefficients it was demonstrated that the relationship between milking rate and standard lactation yield was due to the effect of milking rate on maximum daily yield, lactation length and persistency.

Assessing barley (Hordeum vulgare) response to clipping in the semi-arid Mediterranean climate

2004 ◽  
Vol 44 (1) ◽  
pp. 37
Author(s):  
M. K. J. El-Shatnawi ◽  
N. I. Haddad
Keyword(s):  
Grain Yield ◽  
Yield Components ◽  
Field Experiments ◽  
Grain Weight ◽  
Growing Seasons ◽  
North Eastern ◽  
Pot Trials ◽  
Tiller Density ◽  
Induced Changes ◽  
1000 Grain Weight

Greenhouse pot trials and field experiments were carried out under rain-fed condition in north-eastern Jordan during 1997–98 and 1998–99 growing seasons, to test 3 barley genotypes for their suitability for both forage and grain production. The varieties Rehani and ACSAD176 produced higher forage yields than Rum. In the field, clipping reduced subsequent grain yield per plant by about 18%, lowering grain weight of the main spike from 2.3�g in the control to 1.8 g in the clipped plants. Clipping increased tiller density of barley plants in the field. Decreases in grain yield following clipping could also be attributed to reductions in the number of grains per spike. Clipping decreased the number of grains per spike by about 9% by reducing the number of spikelets per spike. Cutting reduced 1000-grain weight by about 9%. Clipping induced changes in the relative importance of yield components influencing subsequent grain yield. The yield components reduced by clipping were the most important contributors to loss of grain yield.

The relationship between fall dormancy and germplasm source in North American alfalfa cultivars

1996 ◽  
Vol 76 (3) ◽  
pp. 429-433 ◽  
Author(s):  
D. T. Fairey ◽  
N. A. Fairey ◽  
L. P. Lefkovitch
Keyword(s):  
Genetic Diversity ◽  
Regression Analysis ◽  
Plant Height ◽  
North American ◽  
The Other ◽  
Regression Coefficients ◽  
Large Contribution ◽  
Partial Regression ◽  
Fall Dormancy ◽  
The Relationship

Most of the genetic diversity of North American alfalfa cultivars has been accounted for by nine germplasm sources listed in descending order of winter hardiness as follows: Medicago sativa ssp. falcata, Ladak, M. sativa ssp. xvaria, Turkistan, Flemish, Chilean, Peruvian, Indian and African. In most instances, the breeder assigns a fall dormancy score and the relative proportions of each of the nine germplasm source for each cultivar at registration. The fall dormancy score (1 = dormant to 9 = non-dormant), determined by measuring plant height in October after harvest in early September, is used to indicate cultivar adaptation for different regions. This study examines the relationship between germplasm composition and plant height, the equivalence of fall dormancy. The signs on the partial regression coefficients of a multiple regression analysis of plant height on the proportional content of the nine sources of germplasm showed that the fall dormancy fell essentially into two classes, namely, a dormant category, comprising cultivars containing a large contribution of Falcata and Ladak, and a non-dormant category, in which Indian and African germplasm predominate. This does not necessarily preclude the influence of any of the other germplasm sources on fall dormancy, since they represent a rich source of diversity. However, nine distinct classes were not recognisable, perhaps because of the lack of an exact equivalence between fall dormancy class and plant height of the fall regrowth. Since these observations have not been derived in a common nursery, the latitude and latitude × cultivar effects have been disregarded. These limitations should be recognized when using the currently assigned fall dormancy ratings to predict cultivar adaptation. Key words: Alfalfa, fall dormancy, sources of germplasm

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