YIELD OF SPRING WHEAT IN RELATION TO LEVEL OF INFESTATION BY GREENBUGS (HOMOPTERA: APHIDIDAE)

1994 ◽  
Vol 126 (1) ◽  
pp. 61-66 ◽  
Author(s):  
R.W. Kieckhefer ◽  
N.C. Elliott ◽  
W.E. Riedell ◽  
B.W. Fuller
Keyword(s):  
Triticum Aestivum ◽  
Linear Regression ◽  
South Dakota ◽  
Spring Wheat ◽  
Yield Components ◽  
Seed Weight ◽  
Schizaphis Graminum ◽  
Boot Stage ◽  
Steady Decrease ◽  
Number Of Seeds

AbstractThe effect of greenbug, Schizaphis graminum (Rondani), infestations on yield components of early- and late-planted spring wheat, Triticum aestivum L., were measured in 2 successive years in eastern South Dakota. Greenbug populations in plots generally increased rapidly and peaked when wheat plants were in boot stage. Populations then began a steady decrease until anthesis, at which time they were near zero. The number of seeds per spikelet and the number of spikelets per square metre were consistently significantly negatively correlated with aphid-days, whereas average seed weight was significantly negatively correlated with aphid-days for only one planting. A linear regression model that included different intercepts for each spring wheat planting and a common slope relating yield to greenbug feeding days (aphid-days) provided a good fit to the data. Based on the model, a loss of 41 kg of grain per hectare is expected for each 100 aphid-days that accumulate per tiller.

The effect of defoliation on seed production by capeweed (Arctotheca calendula)

1973 ◽  
Vol 13 (65) ◽  
pp. 676 ◽  
Author(s):  
JG McIvor ◽  
DF Smith
Keyword(s):  
Seed Production ◽  
Seed Yield ◽  
Yield Components ◽  
Seed Weight ◽  
Leaf Removal ◽  
Late Flowering ◽  
Individual Seed ◽  
Number Of Seeds

Two experiments were done in pots to assess the effect of defoliation at different times on the seed yield of capeweed (Arctotheca calendula). Yield components measured were: number of seedheads per plant, number of seeds per seedhead, number of seeds per plant, and weight of individual seeds. Of the components of yield, number of florets per seedhead and individual seed weight were maintained under all treatments; number of seedheads and number of seeds per seedhead were more affected by defoliation. Whether grown as spaced plants or in swards, leaf removal did not significantly reduce the number of seeds produced unless combined with bud and flower removal at late flowering only. The results are discussed in relation to the growth and persistence of capeweed in pastures.

INFLUENCE OF IRRIGATION AND SEEDING RATES ON YIELD AND YIELD COMPONENTS OF BRASSICA NAPUS CV. TOWER

1978 ◽  
Vol 58 (3) ◽  
pp. 731-737 ◽  
Author(s):  
J. M. CLARKE ◽  
G. M. SIMPSON
Keyword(s):  
Brassica Napus ◽  
Yield Components ◽  
Seed Weight ◽  
Plant Morphology ◽  
Yield Component ◽  
Seeding Rate ◽  
Brassica Napus L ◽  
Relationship Of ◽  
The Relationship ◽  
Number Of Seeds

An analysis of the yield components of rape (Brassica napus L.) was carried out under field conditions for 2 yr at Saskatoon. Plant morphology and the crop environment were altered by the use of four planting densities and three water regimes. The number of branches per plant was scarcely affected by irrigation, but was reduced by high seeding rates. Number of pods per plant was increased by irrigation and reduced by high seeding rates. The number of seeds per pod was increased by irrigation, but reduced by high seeding rates. The 1,000-seed weight was increased both by irrigation and increased seeding rate, as was seed yield. Yield was positively correlated with 1,000-seed weight in both years. Yield component compensation was evident in the relationship of 1,000-seed weight to pod number and number of seeds per pod.

Irrigation and Nitrogen Studies in s. 23 Ryegrass Grown for Seed: 1. Growth, Development, Seed Yield Components and Seed Yield

1977 ◽  
Vol 88 (3) ◽  
pp. 605-614 ◽  
Author(s):  
P. D. Hebblethwaite
Keyword(s):  
Seed Yield ◽  
Yield Components ◽  
Seed Weight ◽  
Dry Matter ◽  
Field Experiments ◽  
Unit Area ◽  
Yield Response ◽  
Seed Yield Components ◽  
Seed Yields ◽  
Number Of Seeds

SUMMARYThe effects of irrigation and nitrogen on S. 23 perennial ryegrass grown for seed were investigated in a series of field experiments from 1972 to 1974. Irrigation significantly increased seed yield by 16% in 1972 and 52% in 1974 but had no effect in the wet year of 1973. In 1972 maximum deficit reached 110 mm at the end of July and coincided with anthesis. Consequently the yield response was due to an increase in number of seeds per unit area and no other seed yield component was affected. In 1974 peak deficit also reached about 100 mm but started to build up rapidly very early in the season and had reached 80 mm by the time that the first ears emerged. Consequently the yield response was due to increases in number of fertile tillers, number of seeds per unit area and 1000-seed weight.Irrigation had no significant effect on number of florets or seeds, except in 1974 when percentage of florets which produced seed was increased by 2%.Irrigation had some effect on threshed straw yields, total dry matter, harvest index and total number of tillers but where this occurred the response was much smaller than that of seed yield which indicates that irrigation had greater effects on the reproductive development of the crop than on yield of dry matter and tillering patterns. Increasing the quantity of nitrogen from 0 to 80 kg/ha increased seed yields, all seed yield components except 1000-seed weight, threshed straw yields and total dry matter and number of tillers at most sampling dates. Increasing the quantity of nitrogen from 80 to 160 kg/ha had little further effect on the above components except in 1972 where seed yields were significantly decreased.In 1972 number of florets was increased and percentage of florets which produced seed decreased with increasing quantities of nitrogen.

scholarly journals Effect of Mechanical, Cultural and Chemical Weed Control on Yield and Yield Components of Pigeonpeas, Cajanus cajan (L.) Millsp.

1969 ◽  
Vol 58 (4) ◽  
pp. 466-472
Author(s):  
R. Abrams ◽  
F. J. Juliá
Keyword(s):  
Plant Height ◽  
Weed Control ◽  
Yield Components ◽  
Cajanus Cajan ◽  
Seed Weight ◽  
Yield Increase ◽  
Pod Yield ◽  
Yield And Yield Components ◽  
Agricultural Experiment ◽  
Number Of Seeds

Four determinate and four indeterminate types of pigeonpea cultivars and experimental lines were grown at the Isabela Agricultural Experiment Substation during 1971-72 to determine the effects of mechanical, cultural and chemical weed control practices on six characters affecting pigeonpea yield. The chemical, mechanical and hand weed control treatments increased the green pod yield and the number of pods per plant, but had no effect on plant height, number of days to flower, seed weight, and number of seeds per pod. Greatest yield increase was obtained by weed control with chemicals.

scholarly journals Correlation Analysis Between Yield Component Traits and Yield of Watermelon Genotypes (Citrullus lanatus)

2020 ◽  
Vol 4 (1) ◽  
pp. 41-48
Author(s):  
Prinsip Trisna Mulyani ◽  
Budi Waluyo
Keyword(s):  
Genetic Correlation ◽  
Yield Components ◽  
Seed Weight ◽  
Citrullus Lanatus ◽  
Fruit Weight ◽  
Stem Length ◽  
Phenotype Correlation ◽  
Fruit Length ◽  
Number Of Seeds ◽  
Fruit Diameter

Watermelon [Citrullus lanatus (Thunberg) Matsum & Nakai] is a plant that is widely cultivated and contains important nutritional compounds such as citrulline, arginine, and glutathione. In the last few years, the consumption of vegetables and fruits in Indonesia has tended to increase but cannot be fulfilled by domestic production. Yields are influenced by the character of yield components. This research aims to study the relationship between the character of the yield components on the yield in the watermelon. The study was arranged in augmented design and planting material are 75 watermelons genotypes and 3  checks varieties. The results showed that there are some characters of yield components that correlated with yields. The characters of yield components that have positive genetic correlation and positive phenotype correlation with fruit weight are stem length, number of branches, fruit stalk length,  fruit length, fruit diameter, thickness of pericarp, number of seeds per plant, and weight of seeds per plant. The yield components characters that have a negative genetic correlation with fruit weight are day to flowering. The characters of yield components that have positive genetic and phenotype correlation with seed weight per plant are fruit weight, stem length, fruit length, fruit diameter, number of seeds per plant, seed length, and seed width. The Characters of yield components that have a negative genetic correlation with seed weight are day to flowering and the first female flower emerges. The characters of yield components that correlate with the yield are used as selection markers for indirect selection.

scholarly journals Heterosis in soybeans for seed yield components and associated traits

2002 ◽  
Vol 45 (4) ◽  
pp. 401-412 ◽  
Author(s):  
Fábio Pandini ◽  
Natal Antonio Vello ◽  
Ângela Celis de Almeida Lopes
Keyword(s):  
Seed Yield ◽  
Yield Components ◽  
Seed Weight ◽  
Aerial Part ◽  
Agronomic Traits ◽  
Indirect Selection ◽  
Seed Yield Components ◽  
Per Se ◽  
Selection For ◽  
Number Of Seeds

The objective of this research was to quantify heterosis of agronomic traits and evaluate direct and indirect correlations among seed yield and other traits. A diallel involving six parents was grown in two localities. Seed yield (PG), one-hundred seed weight (PCS), number of pods per plant (NV), weight of aerial part of the plant (PPA), harvest index (IC) and number of seeds per pod (NGV) were evaluated. Positive values of heterosis were detected for all traits. Estimates of heterosis components were significative for most traits, showing effects of aditivity and dominance. The specific heterosis was more important than the variety heterosis, mainly in the locality Anhembi. MTBR-95-123800 presented the best potential per se and as parent in crosses, but it was excelled by some of the hybrids in the two localities. Number of pods per plant demonstrated to be suitable for indirect selection for PG.

INTERRELATIONSHIPS AMONG YIELD COMPONENTS AND PLANT GROWTH CHARACTERS, AND THEIR CONTRIBUTION TO YIELD IN TWO SPECIES OF MUSTARD

1980 ◽  
Vol 60 (1) ◽  
pp. 285-289 ◽  
Author(s):  
S. U. AHMED
Keyword(s):  
Plant Growth ◽  
Yield Components ◽  
Seed Weight ◽  
Correlation Coefficients ◽  
Multiple Correlation ◽  
Late Maturity ◽  
Multiple Correlation Coefficients ◽  
Pod Length ◽  
Number Of Seeds ◽  
Growth Characters

Twelve cultivars belonging to two species of Brassica were used to determine the nature and degree of interrelationships among yield components and some plant growth characters, and their contribution to yield. Nine characters were studied and simple, partial, and multiple correlation coefficients were computed. Results indicated that pod length, number of pods per plant, number of seeds per pod, and seed weight per pod were positively and linearly associated with seed yield per plant and that these four component characters of yield were also interrelated with plant height. The percentage of oil in the seeds was positively correlated with seed weight, but negatively with number of seeds per pod. Late maturity was found to be undesirable because it reduces number of pods per plant.

Genotypic and phenotypic variances and correlations in field beans (Vicia faba L.)

1973 ◽  
Vol 81 (3) ◽  
pp. 445-448 ◽  
Author(s):  
T. E. Yassin
Keyword(s):  
Vicia Faba ◽  
Seed Yield ◽  
Environmental Effects ◽  
Yield Components ◽  
Seed Weight ◽  
Genotypic Variance ◽  
Yield And Yield Components ◽  
Vicia Faba L ◽  
Field Beans ◽  
Number Of Seeds

SUMMARYEstimates of genotypic and phenotypic variances and covariances were determined for yield and yield components in ten field beans varieties grown at two locations over three seasons.Substantial amounts of genotypic variance were obtained for yield/plot, 1000-seed weight and number of pods/plant. Variability in number of seeds/pod and much of the variation in yield/plant was attributable to environmental effects and their interaction with the varieties. Seed yield/plot was closely and positively correlated with number of pods/plant and yield/plant, while it was closely and negatively correlated with 1000-seed weight.The implications of these correlations for selection are discussed.

THE EFFECT OF A GENE FOR SEMIDWARFISM (Rht1) ON VARIOUS CHARACTERS IN A SPRING WHEAT CROSS

1986 ◽  
Vol 66 (3) ◽  
pp. 529-533 ◽  
Author(s):  
J. E. BRANDLE ◽  
D. R. KNOTT
Keyword(s):  
Triticum Aestivum ◽  
Spring Wheat ◽  
Yield Components ◽  
Triticum Aestivum L ◽  
The Other ◽  
Lower Weight ◽  
Rainfed Conditions ◽  
Percent Increase ◽  
Positive Correlations ◽  
Wheat Cross

Sixty-four F2-derived F4 lines were produced from a cross between the semidwarf wheat (Triticum aestivum L.) cultivar CSP-44 (Condor sib, Rht1) and the tall cultivar Glenlea (rht1). Thirty-two homozygous tall lines and thirty-two homozygous short lines were tested at Saskatoon under rainfed conditions in 1982 and both rainfed and irrigated conditions in 1983. The objective was to determine the effects of the gene for demidwarfism on yield and other characters under Saskatchewan conditions. The semidwarf lines consistently had more spikes per metre of row and more kernels per spike, but a lower weight per kernel. The percent increase in the number of kernels per spike for the semidwarfs compared to the tails varied more in different environments than the change in the other two components of yield. As a result, the semidwarf lines outyielded the tall lines by 13.1% in the 1982 rainfed test and by 4.1% in the 1983 irrigated test but yielded 2.7% less in the 1983 rainfed test. In general, yield showed only low positive correlations with the yield components, while the yield components showed relatively low negative correlations among themselves.Key words: Wheat, Triticum aestivum, height, semidwarfs, yield components

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