Selection for Female Fertility and Seed Size in Male Sterile Intermediate Wheatgrass, Agropyron Intermedium (Host) Beauv. 1

Crop Science ◽  
1971 ◽  
Vol 11 (4) ◽  
pp. 588-589
Author(s):  
Jurgen Schulz‐Schaeffer ◽  
Jae Ho Kim
Keyword(s):  
Seed Size ◽  
Female Fertility ◽  
Male Sterile ◽  
Intermediate Wheatgrass ◽  
Agropyron Intermedium ◽  
Selection For

scholarly journals GENERAL AND SPECIFIC COMBINING ABILITY IN SUNFLOWER (Helianthus annuus L.) / APTITUD COMBINATORIA GENERAL Y ESPECÍFICA EN EL GIRASOL (Helianthus annuus L.) / APTITUDE À LA COMBINATION GENERAL ET SPECIFIQUE CHEZ LE TOURNESOL (Helianthus annuus L.)

Helia ◽  
2001 ◽  
Vol 24 (34) ◽  
pp. 1-16 ◽  
Author(s):  
Domenico Laureti ◽  
Andrea Del Gatto
Keyword(s):  
Helianthus Annuus ◽  
Combining Ability ◽  
Central Italy ◽  
Specific Combining Ability ◽  
First Year ◽  
Male Sterile ◽  
Breeding Programs ◽  
East Central ◽  
Helianthus Annuus L ◽  
Selection For

SUMMARYA total of 245 test cross progenies obtained by crossing cytoplasmic male sterile (CMS) lines and restorer (RHA) lines were evaluated in replicated trials in 1995 and 1997. Experiments were carried out in two locations (Osimo, East Central Italy and Budrio, Northern Italy) in 1995, whereas in 1997 trials were conducted only in Osimo. General combining ability (GCA) and specific combining ability (SCA) of the parents was evaluated to identify genotypes suitable to be used as testers for breeding programs and to verify the performance of hybrids. The results obtained in 1995 were used to make test crosses in 1996 to be evaluated in 1997. The GCA and SCA of RHA and CMS lines were nearly always significant for all the studied traits when lines were randomly taken in 1995. When selected testers were used on the basis of the results of the first year, the SCA of new RHA lines and GCA of new CMS lines were not significant for achene yield, but they were for the other traits.The best GCA estimates for RHA were often higher than those of CMS, indicating that selection for RHA could be more useful than for CMS. As expected, GCA was always lower than SCA. CMS and RHA, with high variance among their test crosses for yield and many other traits, could be used as testers. The lack of a tester with high variance in all traits requires more than one tester in evaluating lines. The GCA of a line can change in function of the germplasm with which it is combined.

Seed size as a determinant of germination rate in Crepis tectorum (Asteraceae): evidence from a seed burial experiment

1996 ◽  
Vol 74 (4) ◽  
pp. 568-572 ◽  
Author(s):  
Stefan Andersson
Keyword(s):  
Seed Size ◽  
Germination Rate ◽  
Local Population ◽  
Seed Viability ◽  
Seed Burial ◽  
Small Seed ◽  
Crepis Tectorum ◽  
Winter Annual ◽  
Selection For ◽  
The Relationship

The present study of the winter annual Crepis tectorum examines the relationship between seed (achene) size and the extent to which seeds resist germination during the year of their production. I carried out two seed burial experiments, one at an outcrop site occupied by a small-seeded population, and another in an experimental garden with soil from the same field site, with seeds representing the local population and a segregating generation of a cross between two other populations. Using logistic regression with data corrected for seed viability, I found an association between small seed size and failure to germinate in the first autumn. The small seed size characterizing many outcrop populations may have evolved as a response to selection for delaying germination in a habitat subject to unpredictable droughts during the growth season. Keywords: Crepis tectorum, germination, seed bank, seed size.

scholarly journals Selection for bull fertility: a review

2019 ◽  
Vol 4 (1) ◽  
pp. 423-441 ◽  
Author(s):  
Madison L Butler ◽  
Jennifer M Bormann ◽  
Robert L Weaber ◽  
David M Grieger ◽  
Megan M Rolf
Keyword(s):  
Male Fertility ◽  
Assisted Reproductive Technologies ◽  
Average Daily Gain ◽  
Reproductive Technologies ◽  
Female Fertility ◽  
Cattle Production ◽  
Conception Rates ◽  
Beef Bull ◽  
Selection For ◽  
Fertility Traits

Abstract Fertility is a critically important factor in cattle production because it directly relates to the ability to produce the offspring necessary to offset costs in production systems. Female fertility has received much attention and has been enhanced through assisted reproductive technologies, as well as genetic selection; however, improving bull fertility has been largely ignored. Improvements in bull reproductive performance are necessary to optimize the efficiency of cattle production. Selection and management to improve bull fertility not only have the potential to increase conception rates but also have the capacity to improve other economically relevant production traits. Bull fertility has reportedly been genetically correlated with traits such as average daily gain, heifer pregnancy, and calving interval. Published studies show that bull fertility traits are low to moderately heritable, indicating that improvements in bull fertility can be realized through selection. Although female fertility has continued to progress according to increasing conception rates, the reported correlation between male and female fertility is low, indicating that male fertility cannot be improved by selection for female fertility. Correlations between several bull fertility traits, such as concentration, number of spermatozoa, motility, and number of spermatozoa abnormalities, vary among studies. Using male fertility traits in selection indices would provide producers with more advanced selection tools. The objective of this review was to discuss current beef bull fertility measurements and to discuss the future of genetic evaluation of beef bull fertility and potential genetic improvement strategies.

scholarly journals Selection for seed size: The unexpected effects of water availability and density

2018 ◽  
Vol 32 (9) ◽  
pp. 2216-2224 ◽  
Author(s):  
Eugenio Larios ◽  
David Lawrence Venable
Keyword(s):  
Seed Size ◽  
Water Availability ◽  
Selection For

Selection for seed size in monogerm varieties

1962 ◽  
Vol 12 (3) ◽  
pp. 268-272 ◽  
Author(s):  
C. W. Doxtator ◽  
R. H. Helmerick
Keyword(s):  
Seed Size ◽  
Selection For

scholarly journals Selection for Female Fertility Using Censored Fertility Traits and Investigation of the Relationship with Milk Production

2006 ◽  
Vol 89 (11) ◽  
pp. 4438-4444 ◽  
Author(s):  
O. González-Recio ◽  
R. Alenda ◽  
Y.M. Chang ◽  
K.A. Weigel ◽  
D. Gianola
Keyword(s):  
Milk Production ◽  
Female Fertility ◽  
Selection For ◽  
The Relationship ◽  
Fertility Traits

NITRATE ACCUMULATION IN INTERMEDIATE WHEATGRASS

1968 ◽  
Vol 48 (1) ◽  
pp. 85-88 ◽  
Author(s):  
T. Lawrence ◽  
F. G. Warder ◽  
R. Ashford
Keyword(s):  
N Fertilizer ◽  
Nitrate Content ◽  
Nitrate Accumulation ◽  
Intermediate Wheatgrass ◽  
Agropyron Intermedium ◽  
Fertilizer Rates

The effects of six rates of N fertilizer and five frequencies of clipping on the nitrate content of forage from intermediate wheatgrass, Agropyron intermedium (Host.) Beauv., were studied throughout the 1965 growing season.The nitrate content of the forage increased with increasing rates of N fertilizer, and varied with date of harvest. Toxic levels of nitrates (> 2,000 ppm) were found during the period June 5 to July 17 in samples harvested from grass which had been fertilized with 300 and 375 kg/ha of N fertilizer in the spring. Toxic levels were not found in samples from grass fertilized at lower rates. There was an interaction between frequency of clipping and fertilizer rates. At low fertilizer rates the nitrate content of the forage increased as the frequency of clipping was increased, but at the 375-kg/ha rate of fertilizer the opposite was true.It is suggested that fertilizer rates’ in excess of 225 kg/ha N (200 lb/ac N) may result in toxic levels of nitrate in intermediate wheatgrass.

Sign in / Sign up

Export Citation Format

Share Document