Evaluation of Early Generation Testing in Peanuts1

Abstract Six lines representing three botanical varieties, and crosses made in diallel among the six lines were grown at two locations to determine the value of early generation testing in peanuts (Arachis hypogaea L.). Fruit length, percentage sound mature kernels, and percentage fancy size pods of the crosses bulked and measured in F5 generation were correlated with similar measures in F2 generation. F2 generation cross means for yield were not correlated with F5 cross means. Estimates of general combining ability were significant and of greater magnitude than specific combining ability estimates for both F2 and F5 generations for all traits except yield. The average performance of a parental line in crosses in the F2 generation was correlated with its average performance in crosses in the F5 generation for yield, fruit length, sound mature kernels, and fancy size pods. The highest yielding line from nine of the 15 crosses selected using a modified pedigree method equalled or exceeded the yield of the high parent for that cross. Yields of the highest yielding selections, however, were not correlated with the yield of either the F2 or F5 generations of the crosses grown in bulk. Early generation testing in peanuts of crosses between lines representing different botanical varieties appears to be a useful breeding procedure for traits such as fruit length, sound mature kernels, or fancy size pods but has limited value in selecting for yield.

Download Full-text

Combining Ability Estimates in Arachis Hypogaea L. III. F2 Generation of Intra- and Intersubspecific Crosses1

Peanut Science ◽

10.3146/i0095-3679-2-2-5 ◽

1975 ◽

Vol 2 (2) ◽

pp. 50-54 ◽

Cited By ~ 8

Author(s):

J. C. Wynne ◽

J. O. Rawlings ◽

D. A. Emery

Keyword(s):

Arachis Hypogaea ◽

Combining Ability ◽

Early Generation ◽

Ability Estimates ◽

Arachis Hypogaea L ◽

Transgressive Segregants ◽

Parental Lines ◽

F2 Generation ◽

Pod Length ◽

Botanical Varieties

Abstract A hybridization program was initiated to investigate the breeding potential of crosses among diverse peanut (Arachis hypogaea L.) lines. Fifteen crosses in F2 generation generated by crossing six peanut lines representing Valencia, Virginia, and Spanish botanical varieties in diallel without reciprocals were used to estimate combining ability in drilled and space-planted tests. Estimates of both general (GCA) and specific (SCA) combining ability were significant for percent extra large kernels, percent sound mature kernels, kernels/kg, pod length, and yield measured in the drilled test. The GCA estimates were also significant for all characters measured in the space-planted test, while estimates of SCA were significant for five of the six characters. Estimates of GCA were of greater magnitude than SCA estimates for all characters except one. A Spanish line, C2, had the highest GCA effects for yield and sound mature kernels in both drilled and space-planted tests. Although most F2 cross means, especially for the intersubspecific crosses, were less than the midparent value, the presence of transgressive segregants indicated an opportunity for breeding improvement. The depression of F2 means probably resulted from recombination of genes responsible for adaptation of the parental lines. Comparison of results from the space-planted and drilled tests indicates that data from space-planted tests can provide useful information on the performance of crosses in early generation.

Download Full-text

Inheritance of Late Leafspot Resistance and Agronomic Traits in Peanut1

Peanut Science ◽

10.3146/i0095-3679-14-2-9 ◽

1987 ◽

Vol 14 (2) ◽

pp. 86-90 ◽

Cited By ~ 16

Author(s):

S. Jogloy ◽

J. C. Wynne ◽

M. K. Beute

Keyword(s):

Combining Ability ◽

Agronomic Traits ◽

Lesion Size ◽

Culture Technique ◽

Narrow Sense Heritability ◽

Components Of Resistance ◽

Arachis Hypogaea L ◽

Estimate Heritability ◽

Broadsense Heritability ◽

F2 Generation

Abstract Twenty peanut (Arachis hypogaea L.) populations in F2 generation from an M x N mating design involving five late leafspot (Cercosporidium personatum)-resistant female parents and four adapted male parents were evaluated for late leafspot resistance with a detached leaf culture technique. Agronomic traits were evaluated in the field. Objectives were 1) to identify the best parent for agronomic traits and the best source of resistance to late leafspot, 2) determine the correlations among components of resistance, 3) determine the correlations of resistance and agronomic traits, and 4) estimate heritability of late leafspot resistance. General combining ability was highly significant for agronomic traits and for most measurements of late leafspot resistance. Specific combining ability was significant for pod length and seed size. Of the male parents, NC 6 and NC 7 produced the best progenies for both agronomic traits and late leafspot resistance. Components of resistance to late leafspot among resistant female parents were not significantly different. NC 17090 produced the best progenies for pod yield and seed yield. NC 17135 produced progenies with good agronomic traits. Correlations among components of resistance to late leafspot indicated that lines with increased latent period, decreased lesion number, lesion size and defoliation, and reduced spore production can be selected. However, high yielding plants tended to be susceptible to late leafspot. Broadsense heritability for components of resistance was low to moderate (0.13–0.68). Narrow-sense heritability for parameters of resistance was consistently low (0.0–0.128). Selection for late leafspot resistance in the F2 populations was not effective.

Download Full-text

The Effectiveness of Early Generation Testing as Applied to a Recurrent Selection Program in Peanut1

Peanut Science ◽

10.3146/i0095-3679-17-1-14 ◽

1990 ◽

Vol 17 (1) ◽

pp. 44-47 ◽

Cited By ~ 4

Author(s):

T. M. Halward ◽

J. C. Wynne ◽

E. J. Monteverde-Penso

Keyword(s):

Genetic Variation ◽

Recurrent Selection ◽

Agronomic Traits ◽

Early Generation ◽

Yield Improvement ◽

Selection Program ◽

Arachis Hypogaea L ◽

Early Generation Testing ◽

Time Required ◽

Selection Of

Abstract The effectiveness of early generation testing for yield improvement in peanut (Arachis hypogaea L.) was evaluated in an attempt to increase the efficiency of an on-going recurrent selection program by reducing the time required for evaluation and selection. The objectives of the study were to (1) determine if the number of years required per cycle of selection could be reduced; and (2) estimate the amount of genetic variability remaining in the population for yield and four agronomic traits after four cycles of recurrent selection. Sixty-eight random-mated crosses, among the 40 highest yielding lines from the cycle 3 population, were evaluated for yield and agronomic traits in 1985 (S0:1), 1986 (S0:2), and 1987 (S0:3). The results were compared to determine if early generation performance accurately predicts the performance of cross bulks in later generations. No significant correlations were found for yield of entries in the S0:3 and S0:2 or in the S0:3 and S0:1; however, there was a significant correlation between yield of entries in the S0:2 and S0:1 generations. No correlations were found between yield and any of the agronomic traits measured in the S0:3; however, significant correlations were found in the S0:2 between yield and most traits measured. Significant correlations were also found for entries in the S0:3 and S0:2 generations for each agronomic trait measured except number of seed per 20 pods. Early generation testings appears to be useful for selection of certain agronomic traits, but of limited value when selecting for yield. A decrease in genetic variation for yield in the population from the S0:1 to the S0:3 generation was observed; however, the number of crosses equal to or exceeding the yield of the check cultivar increased in later generations. All agronomic traits measured, except number of seed per 20 pods, showed significant genetic variation remaining in the population in both the S0:2 and S0:3 generations. The greater the genetic variation remaining in the population for a given trait, the more likely it is that further improvement of that trait will be realized with additional cycles of selection.

Download Full-text

KERCH STRAIT IN KAMYSH-BURUN SPIT AREA: HIGH-RESOLUTION SEISMOACOUSTIC APPROACH

Materials of XXIV International Coastal Conference, devoted to the 60th anniversary of the “Sea Coasts” Working Group of RAS Council SEA COASTS – EVOLUTION, ECOLOGY, ECONOMY ◽

10.31519/conferencearticle_5b5ce3a3f37b06.98598918 ◽

2018 ◽

Author(s):

В. Зинько ◽

V. Zin'ko ◽

А. Зверев ◽

A. Zverev ◽

М. Федин ◽

...

Keyword(s):

High Resolution ◽

Fracture Zone ◽

Sedimentary Cover ◽

Sedimentary Rocks ◽

The West ◽

Early Generation ◽

The Third ◽

Azov Sea ◽

Kerch Strait ◽

Made In

The seismoacoustical investigations was made in the western part of the Kerch strait (Azov sea) near Kamysh-Burun spit. The fracture zone with dislocated sedimentary rocks layers and buried erosional surface was revealed to the west of spit. Three seismofacial units was revealed to the east of spit. The first unit was modern sedimentary cover. The second ones has cross-bedding features and was, probably, the part of early generation of Kamysh-Burun spit, which lied to the east of its modern position. The lower border of the second unit is the erosional surface supposed of phanagorian age. The third unit is screened by acoustic shedows in large part.

Download Full-text

Comparison of Three Procedures for Early Generation Testing of Soybean

Crop Science ◽

10.2135/cropsci2002.0705 ◽

2002 ◽

Vol 42 (3) ◽

pp. 705 ◽

Cited By ~ 6

Author(s):

Steven K. St. Martin ◽

Isaias O. Geraldi

Keyword(s):

Early Generation ◽

Early Generation Testing

Download Full-text

Bulk, Pedigree, and Early Generation Testing Breeding Methods Compared in Soybeans 1

Crop Science ◽

10.2135/cropsci1973.0011183x001300030022x ◽

1973 ◽

Vol 13 (3) ◽

pp. 363-364 ◽

Cited By ~ 8

Author(s):

V. D. Luedders ◽

L. A. Duclos ◽

A. L. Matson

Keyword(s):

Breeding Methods ◽

Early Generation ◽

Early Generation Testing

Download Full-text

Diallel cross among fresh market tomato inbreeding lines

Horticultura Brasileira ◽

10.1590/s0102-05362012000200011 ◽

2012 ◽

Vol 30 (2) ◽

pp. 246-251 ◽

Cited By ~ 11

Author(s):

Lívia M de Souza ◽

Maria Elisa AGZ Paterniani ◽

Paulo César T de Melo ◽

Arlete MT de Melo

Keyword(s):

Combining Ability ◽

Yield Components ◽

Block Design ◽

Diallel Cross ◽

Fruit Yield ◽

Soluble Solids ◽

Width Ratio ◽

Parental Line ◽

Fresh Market ◽

Fruit Number

The general combining ability (GCA), specific combining ability (SCA), and heterosis were studied in a complete diallel cross among fresh market tomato breeding lines with reciprocal excluded. Fifteen genotypes (five parents and ten hybrids) were tested using a randomized complete block design, with three replications, and the experiments were conducted in Itatiba, São Paulo state, Brazil, in 2005/06. The yield components evaluated were fruit yield per plant (FP), fruit number per plant (FN), average fruit weight (FW); cluster number per plant (CN); fruit number per cluster (FC), fruit wall thickness (FT) and number of locules per fruit (NL). Fruit quality components evaluated were total soluble solids (SS); total titratable acidity (TA); SS/TA ratio, fruit length (FL); fruit width (WI); length to width ratio (FL/WI). The data for each trait was first subjected to analysis of variance. Griffing's method 2, model 1 was employed to estimate the general (GCA) and specific (SCA) combining abilities. Parental and hybrid data for each trait were used to estimate of mid-parent heterosis. For plant fruit yield, IAC-2 was the best parental line with the highest GCA followed by IAC-4 and IAC-1 lines. The hybrids IAC-1 x IAC-2, IAC-1 x IAC-4 and IAC-2 x IAC-4 showed the highest effects of SCA. High heterotic responses were found for fruit yield and plant fruit number with values up to 49.72% and 47.19%, respectively. The best hybrids for fruit yield and plant fruit number were IAC-1 x IAC-2, IAC-1 x IAC-4 and IAC-2 x IAC-5, for fruit yield and plant fruit number, the main yield components.

Download Full-text

Genetic parameters and combining ability of some important traits in rice (Oryza sativa L.)

Genetika ◽

10.2298/gensr1703001h ◽

2017 ◽

Vol 49 (3) ◽

pp. 1001-1014 ◽

Cited By ~ 1

Author(s):

Hasanalideh Haghighi ◽

Ezatollah Farshadfar ◽

Mehrzad Allahgholipour

Keyword(s):

Combining Ability ◽

Genetic Parameters ◽

Amylose Content ◽

Oryza Sativa L ◽

Block Design ◽

Regression Line ◽

Diallel Cross ◽

Combining Ability Analysis ◽

Additive Gene ◽

F2 Generation

In order to study the combining ability, genetic parameters and gene actions of yield, yield components and quality characters in rice, fifteen F2 generation of a 6?6 diallel cross, excluding reciprocals, was grown in a randomized complete block design (RCBD) with three replications. The results of analysis of variance showed significant differences between the genotypes for grain yield (GY), 100-grain weight (HGW), number of panicles per plant (PN), panicle length (PL), number of full grains per panicle (FGN) and for quality characters including amylose content (AC) and gel consistency (GC). The results of combining ability analysis revealed that general combining ability (GCA) and specific combining ability (SCA) were significant for characters GY, FGN, GC, AC, HGW and PN indicating the involvement of additive and non-additive effects in their inheritance, however high amounts of Bakers ratio remarked that additive gene effect had more portion in controlling these traits. The best combiners for GY, HGW, FGN, PN and PL, were RI18447-2, IR 50, Daylamani, RI18430-46 and Daylamani respectively. For AC and GC, the best combiner was Daylamani. Hayman's graphs showed that regression line passed below the origin cutting Wr axis in the negative region for HGW, PN, PL and GC, indicating the presence of over dominance. Estimates of genetic parameters showed significant amount of H1 and H2, and non-significant amount of D for the characters GY, PN, PL and GC, which confirmed the existence of dominance in the inheritance of these traits.

Download Full-text