FERTILITY OF BARLEY AUTOTETRAPLOIDS: I. FERTILITY IN SUCCESSIVE GENERATIONS OF FOUR AUTOTETRAPLOID BARLEY VARIETIES AND THE EFFECT OF SELECTION FOR FERTILITY IN THE O.A.C. 21 AUTOTETRAPLOID

1959 ◽  
Vol 39 (1) ◽  
pp. 98-107 ◽  
Author(s):  
E. Reinbergs ◽  
L. H. Shebeski
Keyword(s):  
Promising Method ◽  
Low Fertility ◽  
Fertility Level ◽  
Seed Setting ◽  
The Mean ◽  
Selection For ◽  
Successive Generations ◽  
Subsequent Selection

The differences in fertility of four colchicine-induced autotetraploid barley varieties (Brant, Montcalm, O.A.C. 21 and York) were determined and compared in four successive generations following the induction of tetraploidy. Despite a wide fertility range within each autotetraploid, the varieties tested varied considerably in their mean per cent fertility. Within each variety the mean per cent fertility remained relatively constant from generation to generation. The Montcalm tetraploid had the lowest mean fertility, fluctuating from generation to generation within a range of 6.0 to 10.1 per cent. The O.A.C. 21 tetraploid had the highest mean fertility, fluctuating within a range of 40.0 to 51.3 per cent.Significant differences in fertility of the four autotetraploid varieties were interpreted as indicating that seed-setting ability may be genetically controlled and, therefore, hybridization and subsequent selection could be a promising method for increasing fertility.Continuous selection for either high or low fertility from the C1 to C4 generation did not change the mean per cent fertility level in the O.A.C. 21 tetraploid.

Breeding creeping-rooted lucerne for the subtropics

1967 ◽  
Vol 18 (6) ◽  
pp. 891 ◽  
Author(s):  
LA Edye ◽  
KP Haydock
Keyword(s):  
Survival Rates ◽  
Adventitious Shoots ◽  
Mass Selection ◽  
Genotypic Correlation ◽  
Specific Effects ◽  
The Mean ◽  
Selection For ◽  
Successive Generations ◽  
Seed Yields ◽  
Better Than

A lucerne-breeding programme was undertaken at Lawes, south-eastern Queensland, to transfer the creeping-rooted habit from Heinrichs's Canadian strains to subtropical lucerne varieties. Before intensive selection commenced, the inheritance and association of three characters, summer yield, winter yield, and the number of extra crowns originating as adventitious shoots from roots, were determined in the F2 and F3 generations. The F2 genotypic variances for summer yield, winter yield, and number of extra crowns were predominantly additive and were respectively 81, 53, and 54% of their phenotypic variances. The genotypic correlation coefficient for winter yield and number of extra crowns was negative ( rG = –0.18), consisting of a negative additive correlation rg = –0.55 and a positive non-additive correlation rs = 0.50. In the F3 generation the approximate genotypic correlation for these two characters was small and positive and composed of a nearly zero additive correlation and a high positive non-additive correlation. Simultaneous mass selection for summer yield, winter yield. and creeping-rootedness was undertaken in the F3 generation, and the combining ability variances and covariances for these characters were studied in the F4 generation. All three variables were positively associated in their general and specific effects, and the majority of families did not differ significantly from Hunter River in winter and summer yield. The seed production of ten F4 families was studied and it was found that eight families were significantly lower seed producers than Hunter River, their seed yields ranging from 20 to 47% of the mean for Hunter River. Covariance analysis showed seed yield and number of extra crowns to be negatively associated in the F4 generation. The changes in creeping-rootedness in the successive generations F1 to F5 were 2, 9, 34, 19, and 59% compared with a mean of 4% for Heinrichs's Canadian strains at Lawes. Creeping-rooted individuals survived better than non-creeping-rooted plants of similar genotype and better than Hunter River, particularly in the F4 generation, where the respective survival rates were 75, 27, and 23% 19 months after transplanting in the field

scholarly journals SELECTION FOR YIELD AT TWO FERTILIZER LEVELS IN SMALL-SEEDED COMMON BEAN

1989 ◽  
Vol 69 (3) ◽  
pp. 1011-1017 ◽  
Author(s):  
SHREE P. SINGH ◽  
CARLOS A. URREA ◽  
J. ARIEL GUTIERREZ ◽  
JAMES GARCIA
Keyword(s):  
Phaseolus Vulgaris ◽  
Soil Fertility ◽  
Common Bean ◽  
Seed Yield ◽  
Soil Phosphorus ◽  
Low Fertility ◽  
Gene Pools ◽  
High Fertility ◽  
The Mean ◽  
Selection For

Selection for seed yield (visual in the F2, visual and plot yield from the F3 to F5, and yield tests in F6) was carried out in two crosses of common bean (Phaseolus vulgaris L.) in high and low soil fertility environments at CIAT-Quilichao, Colombia. Parents were small-seeded and tolerant to low soil phosphorus, possessed indeterminate bush growth habit, and belonged to lowland tropical gene pools of Middle America. The mean yield of selected lines from low (LFS) and high (HFS) soil fertility environments was significantly higher than the mean of the parents in both crosses when tested in high fertility (HF) but not in low fertility (LF). The highest yielding LFS and HFS lines from A 286 × (G 5059 × A 80) and the LFS line from A 286 × ICA Pijao outyielded the best check cultivar, Carioca, in HF. No line yielded significantly more than A 286, the best parent used in both crosses. The mean effect of fertilizer levels on selection for seed yield was nonsignificant. Lines selected under two environments showed similar but average response and high stability of performance under variable environments. Low soil fertility accelerated maturity and reduced 100-seed weight and seed yield.Key words: Phaseolus vulgaris, bean (small-seeded common), selection for yield, soil fertility, Middle American gene pools, regression coefficient

scholarly journals Screening of French Bean (Phaseolus vulgaris L.) Genotypes against Alternaria Leaf Spot Caused by (Alternaria alternata) under Dryland Conditions of Kashmir

2021 ◽  
pp. 25-30
Author(s):  
Sabiya Bashir ◽  
Mohammad Najeeb Mughal ◽  
Zahida Rashid ◽  
Shabeena Majid ◽  
Sabeena Naseer ◽  
...  
Keyword(s):  
Alternaria Alternata ◽  
Leaf Spot ◽  
Disease Incidence ◽  
French Bean ◽  
Phaseolus Vulgaris L ◽  
Dryland Agriculture ◽  
Disease Reaction ◽  
The Mean ◽  
Selection For ◽  
Resistant Genotypes

Sixty-three genotypes of  french bean was screened against leaf spot (Alternaria  alternata) in sick plots at Research Farm of Dryland Agriculture Research Srinagar, Rangreth during  Kharif  2018 and 2019. The highest mean disease incidence ranged from 0.00 to 85.00 per cent  with  the mean disease intensity ranged from 0.00 to 53.26 per cent .One genotype namely  ‘Local Pulwama’ was highly susceptible in their disease reaction. Among the screened germplasm, ‘Highly Resistant’ genotypes was SKU-R-601, SKUA-R-105, SKU-R-927, DARS-25, DARS-66, DARS-R-615,  while as ‘Susceptible’ genotypes was  DARS-8, DARS-12,  DARS-11, SKUAST-R-155, SKU-R-928, DARS-7, DARS-R-4, Bhaderwah (L),  Local  Kupwara black and Raj Jawala. Local Pulwama was found to be a highly susceptible (HS) genotype.  Twenty nine genotypes namely., DARS-16, DARS-9, DARS-54, DARS-39, VL-125, DARS-63, ENTO-504, SKUAST-204,SKU-R-925, DARS-60, DARS-109, DARS-43, DARS-44, SKU-R-23, DARS-4, DARS-74, SKU-R-105, DARS-40, DARS-23, DARS-18, SKU-R-71, WB-341, SKU-R-605, Uri local, Shopian (L), SKU-R-23, DARS-71, SSGB-729, DARS-R-19 showed resistant reaction to disease. The selection for resistance was based on the reaction of varieties on leaves.

Chemistry, mineralogy and microbiology of termite mound soil eaten by the chimpanzees of the Mahale Mountains, Western Tanzania

1999 ◽  
Vol 15 (5) ◽  
pp. 565-588 ◽  
Author(s):  
William C. Mahaney ◽  
Jessica Zippin ◽  
Michael W. Milner ◽  
Kandiah Sanmugadas ◽  
R. G. V. Hancock ◽  
...  
Keyword(s):  
Sandy Loam ◽  
Termite Mound ◽  
Mahale Mountains ◽  
Mahale Mountains National Park ◽  
The Mean ◽  
Selection For ◽  
Bacteria And Fungi ◽  
And Control ◽  
Very High ◽  
Control Samples

Subsamples of termite mound soil used by chimpanzees for geophagy, and topsoil never ingested by them, from the forest floor in the Mahale Mountains National Park, Tanzania, were analysed to determine the possible stimulus or stimuli for geophagy. The ingested samples have a dominant clay texture equivalent to a claystone, whereas the control samples are predominantly sandy clay loam or sandy loam, which indicates that particle size plays a significant role in soil selection for this behaviour. One potential function of the clays is to bind and adsorb toxins. Although both termite mound and control samples have similar alkaloid-binding capacities, they are in every case very high, with the majority of the samples being above 80%. The clay size material (<2 μm) contains metahalloysite and halloysite, the latter a hydrated aluminosilicate (Al2Si2O4·nH2O), present in the majority of both the termite mound soil and control soil samples.Metahalloysite, one of the principal ingredients found in the pharmaceutical Kaopectate™, is used to treat minor gastric ailments in humans. The soils commonly ingested could also function as antacids, as over half had pH values between 7.2 and 8.6. The mean concentrations of the majority of elements measured were greater in the termite mound soils than in the control soils. The termite mound soils had more filamentous bacteria, whereas the control soils contained greater numbers of unicellular bacteria and fungi.

Vital statistics for an experimental flock of Merino sheep. III. Factors affecting wool and body characteristics, including the effect of age of ewe and its possible interaction with method of selection

1966 ◽  
Vol 17 (4) ◽  
pp. 557 ◽  
Author(s):  
GH Brown ◽  
HN Turner ◽  
SSY Young ◽  
CHS Dolling
Keyword(s):  
Body Weight ◽  
Fibre Diameter ◽  
Vital Statistics ◽  
Fibre Volume ◽  
Age Changes ◽  
Factors Affecting ◽  
Fibre Number ◽  
The Mean ◽  
Selection For ◽  
Staple Length

Estimates were made of the effects of the following factors on 10 fleece and body characteristics measured on breeding ewes aged 1½ to 10½ years in three mating groups over a period of 15 years: age of ewe, single or twin birth, age of dam, the ewe's own lambing performance, the year in which measurements were made, and the year in which each set of ewes was born. Two groups (S and MS) were under selection for high clean wool weight at 15–16 months, with a ceiling on wrinkle score and fibre diameter, while the third (C) was a random control. Changes with age were present in all characteristics and were similar in the three groups. The finding that selection on wool weight at an early age had no effect on subsequent age changes in any characteristic is of considerable importance. Greasy and clean wool weight reached a maximum at 34 years, then declined by 0.3–0.2 1b per year. Percentage clean yield, fibre diameter, body weight, and wrinkle score had maxima at 5½ to 6½ years. Staple length fell consistently by approximately 0.2 cm per year, while face cover rose consistently but slightly. Crimp number rose, fell, and rose again, while fibre number rose, fell, and remained constant from 4½ years. The chief source of increase in wool weight from l½ to 3½ years was an increase in the total number of fibres. The chief source of the subsequent fall was a decrease in fibre volume, with a minor contribution from a fall in total fibre number after 6½ years. Twin-born ewes cut 0.21 lb (4.2% of the mean) less clean wool per year over their lifetime than single-born ewes, while the progeny of 2-year-old ewes cut 0.32 lb (6.4%) less than the progeny of adults. The main source of lower weight in each case was a lower total fibre number. Pregnancy lowered clean wool weight more than lactation, the separate effects being 0.87 and 0.38 lb respectively (17.4 and 7.7% of the mean) and the combined effect 1.25 1b or 25.1%. Pregnancy lowered total fibre number but lactation had no further effect. Mean clean wool weights over all ages in the C group varied from year to year, the range being from 1.08 lb (21.6%)below the mean to 0.97 lb (19.4%) above. Differences in total fibre number contributed between one-third and two-thirds of the variation. Ewes born in consecutive years in the S and MS groups showed marked upward trends in clean wool weight, fibre number, and staple length, with a marked downward trend in crimp number and a slight upward trend in body weight. These trends demonstrate direct and correlated responses to the strong selection for high clean wool weight at 15–16 months of age, and the associated slight selection against fibre diameter and wrinkle score. The mean annual increases in clean wool weight were 0.15 and 0.11 Ib (3.0 and 2.2%) in the S and MS groups, approximately 40% of the increase arising from increased total fibre number and 40% from increased staple length. The effects of age and lambing performance can be used to predict productivity in flocks of differing age structures. As the casting age rises to 54 years changes in productivity are negligible. With a rise in casting age to 7½ years the average clean wool weight of the flock would fall by 0.14 lb, with a slight decrease in staple length and crimp number. These changes need to be balanced against any increased lambing percentage or decreased annual genetic gain due to increased generation interval. Comparison with other available figures indicates that age changes may vary from one area to another.

Walkie-talkie evolution: Bipedalism and vocal production

2004 ◽  
Vol 27 (4) ◽  
pp. 520-521 ◽  
Author(s):  
Robert R. Provine
Keyword(s):  
Bipedal Locomotion ◽  
Vocal Production ◽  
Quadrupedal Locomotion ◽  
Selection For ◽  
Vocal Evolution ◽  
Subsequent Selection

A converging pattern of evidence from laughter, tickling, and motherese suggests that bipedal locomotion plays a critical and unanticipated role in vocal evolution. Bipedalism frees the thorax of its support role during quadrupedal locomotion, which permits the uncoupling of breathing and striding necessary for the subsequent selection for vocal virtuosity and speech.

SELECTION FOR SEED SET IN NONINBRED AND PARTLY INBRED POPULATIONS OF ALFALFA

1977 ◽  
Vol 57 (3) ◽  
pp. 873-881 ◽  
Author(s):  
R. MICHAUD ◽  
T. H. BUSBICE
Keyword(s):  
Medicago Sativa ◽  
Seed Set ◽  
Exponential Model ◽  
Seed Setting ◽  
Medicago Sativa L ◽  
Selection For ◽  
Inbred Populations ◽  
The Relationship ◽  
Advanced Generation ◽  
Coefficient Of Inbreeding

Alfalfa (Medicago sativa L.) is a highly heterozygous cross-pollinating species, and most breeding efforts have been conducted on noninbred populations. The purpose of this study was to determine whether greater breeding progress could be made by selecting within partly inbred populations rather than within noninbred ones. One hundred and twenty F1 (noninbred) and 120 S1 (partly inbred) plants that were issued from crossing and selfing four alfalfa clones were evaluated for self-fertility. The most self-fertile 10% of the plants from each family were selected in each population. The selected plants within each level of inbreeding were intercrossed to produce an advanced generation in which the effectiveness of the selection was evaluated. Selection increased both self- and cross-fertility in the advanced generation. Selection was more effective at the F1 level than at the S1 level. Fertility was reduced drastically by inbreeding. The average self-fertility of the S1’s was only about 7% of the cross-fertility of their parental clones. An exponential model was proposed to describe the relationship between seed setting and the coefficient of inbreeding in the developing zygote. This model explained 95% of the variation among 11 unselected populations having differing levels of inbreeding.

Relative economic importance of some wool quality traits for Merino and crossbred wool types

1970 ◽  
Vol 10 (46) ◽  
pp. 544 ◽  
Author(s):  
PD Mullaney ◽  
ID Sanderson
Keyword(s):  
Selection Index ◽  
Fibre Diameter ◽  
Economic Importance ◽  
Quality Traits ◽  
Regression Analyses ◽  
Independent Variables ◽  
Economic Weights ◽  
Australian Wool ◽  
The Mean ◽  
Selection For

The economic weights of various quality traits of both Merino and crossbred wool types hive been estimated. Australian averages of clean wool prices for Australian Wool Board wool types, into which mid-side samples of fleece were classified, have been used.For each of fifteen seasons, 1953-54 to 1967-68, the mean clean wool price for each wool type was expressed as a percentage of the mean wool price for all types in that season. Rank correlations for price-type means were high between seasons, varying between 0.91 and 0.98. Further analyses were therefore performed using prices averaged for the 15 seasons. Multiple regression analyses were carried out, the dependent variable being the mean price for each fleece type, expressed as a percentage of the average price of all types for al) seasons and the independent variables being the measurement of fibre diameter, crimps per inch and length, and the subjective gradings of colour, handle, character, and quality number. For both Merino and crossbred wool types, the major determinants of price were quality number, colour, and handle, with quality number being of overwhelming importance. The remaining variables were not important as joint determinants of price, and were deleted from the analyses. Quality number, colour, and handle controlled about 81 and 86 per cent of the variation in price for Merino and crossbred wool types. It is likely that most progress in selection for wool production would be made by incorporating these findings into a selection index.

A note on the voluntary intake of Andropogon gayanus hay by cattle, as affected by level of feeding

1972 ◽  
Vol 15 (1) ◽  
pp. 85-88 ◽  
Author(s):  
G. Zemmelink ◽  
R. J. Haggar ◽  
J. H. Davies
Keyword(s):  
Protein Content ◽  
Feed Intake ◽  
Linear Effect ◽  
Low Level ◽  
Strong Selection ◽  
Andropogon Gayanus ◽  
The Mean ◽  
Voluntary Intake ◽  
Selection For ◽  
White Fulani

SUMMARYUnchaffed Andropogon gayanus hays, harvested in July, September, early-October, late-October and November, and the July to November regrowth, were offered to White Fulani heifers at three levels of feeding.Animals on all hays selected for protein and the mean intake of the different hays was closely related to the protein content of the consumed forage. At the low level of feeding all animals, except those on the July hay, left more than 15% residue. Nevertheless, higher levels of feeding had a marked linear effect on feed intake. This effect was largely independent of the effect of level of feeding on the protein content of the consumed ration and was associated with a strong selection for leaves.

A Comparative Study of Semen Characteristics and Testosterone Concentration in Ram Breeds of Saudi Arabia

2020 ◽  
Author(s):  
A. A. Al-kawmani ◽  
M. A. Farah ◽  
S. Nahdi ◽  
A. H. Harrath ◽  
H. Al-Jawdah
Keyword(s):  
Saudi Arabia ◽  
Age Groups ◽  
Sperm Concentration ◽  
Breeding Programs ◽  
Testosterone Concentration ◽  
Semen Characteristics ◽  
The Mean ◽  
Selection For ◽  
Live Sperm ◽  
Sperm Output

The goal of this study was to evaluate and compare the semen characteristics, and testosterone concentration for three breeds raised under hot, desert conditions in Saudi Arabia. A total of 150 rams (Najdi, Naemi, and Harri) were used, aged 12, 18, 24, 30 and 36 months (ten rams from each breed in each age group). Body weight and testicular parameters were measured. In addition, testosterone concentration (TC), ejaculate volume (EV), sperm concentration (SC), total sperm output per ejaculate (TSO), live sperm percentage (LSP), sperm progressive motility (SPM) and sperm mass motility (SMM). The results show that TC and EV differed significantly (P less than 0.01) between breeds. At 36 months, semen characteristics (TSO, SMM and SPM) differed significantly among breeds. Naemi rams were superior to Najdi and Harri in terms of the mean live sperm percentage (LSP) for all age groups. These results may assist in ram selection for breeding programs based on high reproductive performance.

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