Reproductive Cold Stress Tolerance in Sorghum F1 Hybrids is a Heterotic Trait

Agronomy ◽

10.3390/agronomy9090508 ◽

2019 ◽

Vol 9 (9) ◽

pp. 508

Author(s):

André Schaffasz ◽

Steffen Windpassinger ◽

Rod Snowdon ◽

Benjamin Wittkop

Keyword(s):

Cold Stress ◽

Cold Tolerance ◽

Combining Ability ◽

Pollen Viability ◽

Field Trials ◽

Hybrid Breeding ◽

F1 Hybrid ◽

Poor Seed ◽

High Heritability

The sensitivity of sorghum to pre-flowering cold stress, resulting in reduced pollen viability and poor seed set, is a major constraint for expanding growing areas into higher altitudes and latitudes. Nevertheless, compared to juvenile cold tolerance, reproductive cold tolerance in sorghum has received much less attention so far, and very little is known about its inheritance in F1-hybrids. We have composed a representative factorial (n = 49 experimental F1-hybrids) for a comprehensive study on heterosis and combining ability for crucial tolerance traits as spikelet fertility (panicle harvest index), seed yield and pollen viability, using field trials in stress- and control environments in Germany and Mexico as well as climate chamber experiments. Our results indicate a heterotic and rather dominant inheritance of reproductive cold tolerance in sorghum, with strong effects of female general combining ability (GCA) on F1-hybrid performance in our material. These findings, together with the comparatively low contribution of specific combining ability (SCA) effects and high heritability estimates, suggest that robust and efficient enhancement of reproductive cold tolerance is feasible via hybrid breeding.

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Combining Ability and Heritability of Resistance to Early and Late Leafspot of Peanut1

Peanut Science ◽

10.3146/i0095-3679-13-1-4 ◽

1986 ◽

Vol 13 (1) ◽

pp. 10-14 ◽

Author(s):

W. F. Anderson ◽

J. C. Wynne ◽

C. C. Green ◽

M. K. Beute

Keyword(s):

Combining Ability ◽

Additive Genetic Variance ◽

Rank Correlation ◽

Cercospora Arachidicola ◽

F1 Hybrid ◽

Detached Leaf ◽

F2 Population ◽

Parental Lines ◽

Abstract Four parental lines with resistance to early leafspot caused by Cercospora arachidicola Hori and four parental lines with resistance to late leafspot caused by Cercosporidium personatum (Berk. & Curt.) Deighton and the F1 hybrid progeny from crosses between the two groups of parents were evaluated for resistance to both leafspot diseases in the greenhouse using a detached leaf technique. The subsequent F2 plants of all crosses were evaluated in the field for resistance to early leafspot in order to estimate combining ability effects for components of partial resistance and to identify parents useful in developing lines resistant to both diseases. General combining ability, attributed largely to additive genetic variance, accounted for the largest portion of the variability among the F1 and F2 generations for most parameters of resistance to both early and late leafspots. Reciprocal effects and heterosis toward the susceptible parents were also significant for parameters of resistance to the two pathogens. GP-NC 343 and FESR 5-P2-B1 were the best parents for incorporating genes for resistance to both early and late leafspots. Progenies of NC 17090 had a high level of resistance to late leafspot in detached leaf tests and progeny of PI 350680 had reduced defoliation from early leafspot in the field. Broad-sense heritabilities ranged from 0.2 to 0.4 for parameters of resistance to early leafspot estimated from the pooled variances of F2 plants of all crosses planted in the field. Parameters of resistance evaluated in the greenhouse for F1 hybrids were compared to parameters evaluated in the field for the F2 population by rank correlation of entry means. Latent period and sporulation of the fungus on detached leaves of F1 generation plants correlated (r = −0.46 and 0.54, respectively) with defoliation of F2 plants in the field.

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Influence of different types of sterile cytoplasms (A3, A4, 9E) on the combining ability of CMS lines of sorghum

Vavilov Journal of Genetics and Breeding ◽

10.18699/vj20.648 ◽

2020 ◽

Vol 24 (6) ◽

pp. 549-556

Author(s):

O. P. Kibalnik ◽

L. A. Elkonin

Keyword(s):

Grain Yield ◽

Plant Height ◽

Combining Ability ◽

Thermal Coefficient ◽

Negative Effects ◽

F1 Hybrid ◽

Positive Effects ◽

Different Types ◽

Investigation of the effect of the cytoplasm on the combining ability (CA) of lines with cytoplasmic male sterility (CMS) is of considerable interest in terms of understanding the genetic functions of the cytoplasm and for practical purposes to create hybrids with improved economically valuable traits. In order to investigate the effect of different types of sterile cytoplasm (A3, A4, 9E) on CA in sorghum, we studied the manifestation of a number of biological and agronomic traits in 54 F1 hybrid combinations obtained using iso-nuclear CMS lines with the nuclear genome of the line Zheltozernoye 10, differing only in the types of sterile cytoplasm (A3, A4 and 9E). Eighteen varieties and lines of grain sorghum developed at the Russian Research and Project-technological Institute of Sorghum and Maize were used as paternal parents. The CA was determined by the topcross method. F1 hybrids and their parents were grown in 2015–2017 in conditions of insufficient (2015–2016: HTC (hydro-thermal coefficient) = 0.32–0.66), or good water availability conditions (2017: HTC = 1.00). On average, for three years of testing, a positive effect of the 9E cytoplasm on the general combining ability (GCA) (0.63) and negative effects of the A3 and A4 cytoplasms (–0.32 and –0.31) for the inflorescence length were noted. In dry seasons, significant positive effects of the 9E cytoplasm on GCA for the length of the largest leaf, and positive effects of the A3 cytoplasm on GCA for the plant height, and negative effects of the A4 cytoplasm on GCA for these traits were observed. No differences were observed during the wet season. The type of CMS did not affect the GCA for the width of the largest leaf and grain yield. The dispersion of specific combining ability (SCA) in the dry seasons was significant for the following traits: leaf length, plant height, panicle length and width, and grain yield, the 9E cytoplasm had the highest SCA dispersion, whereas the A4 cytoplasm had the smallest one. The data obtained indicate that different types of sterile cytoplasm of sorghum make a different contribution to CA under conditions of drought stress.

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Combining capacity and heterosis in eggplant hybrids under high temperatures

Horticultura Brasileira ◽

10.1590/s0102-053620190315 ◽

2019 ◽

Vol 37 (3) ◽

pp. 348-353

Author(s):

Ricardo de N Valadares ◽

Danieli A Nóbrega ◽

Lilian B de Lima ◽

Jordana Antônia dos S Silva ◽

Ana Maria M dos Santos ◽

...

Keyword(s):

High Temperatures ◽

Combining Ability ◽

Phenotypic Variability ◽

Pollen Viability ◽

Fixation Index ◽

Gene Effects ◽

F1 Hybrid ◽

Fruit Length ◽

Additive Gene Effects ◽

ABSTRACT The objective of this work was to estimate the combinatorial capacity and heterosis of eggplant hybrids under high temperature conditions. Seven genitors, twelve hybrid combinations, originated from a partial diallel, and the Ciça F1 hybrid, as control, were evaluated. The experiment was conducted under greenhouse conditions in randomized block design with four replications, from April to December 2017. The assessed traits related to high temperatures were pollen viability (PV) and fruit fixation index (FFI); the morphoagronomic traits were number of fruits per plant (NFP), fruit weight (FWe), production per plant (PP), fruit length (FL), fruit width (FWi), fruit length/width ratio (FLWR) and plant height (PH). The variance analysis showed greater participation of the additive gene effects in relation to the non-additive gene effects in most traits, except for PV. The genitors CNPH 141, CNPH 135, CNPH 109 and CNPH 51 stood out with favorable gene effects to obtain genotypes tolerant to high temperatures, since they present good general combining ability (GCA) for the traits FFI, NFP and PP. The 1x4 and 3x4 hybrids presented positive estimates for both GCA and specific combining ability (SCA), demonstrating a greater potential to be used in breeding to increase the FFI, NFP and PP, under high temperatures. The 1x4, 1x5 and 1x6 hybrids expressed positive heterosis for most analyzed traits. The 1x4 hybrid stood out for the highest averages for PV, FFI, NFP and PP. For FWe, FL, FWi and FLWR, both positive and negative heterosis were observed, as consequence of the phenotypic variability of the genitors for these traits and suggests the possibility of selection for different sizes and formats.

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Heterosis and Combining Abilities in a Diverse Seven-Parent Pearl Millet Population Diallel Tested in West Africa

10.21203/rs.3.rs-232609/v1 ◽

2021 ◽

Author(s):

Sonali Dutta ◽

Felix T. Sattler ◽

Anna Pucher ◽

Drabo Inoussa ◽

Ahmad Issaka ◽

...

Keyword(s):

West Africa ◽

Pearl Millet ◽

Combining Ability ◽

Pennisetum Glaucum ◽

Smallholder Farmers ◽

Hybrid Breeding ◽

Variance Ratios ◽

High Heritability ◽

Quantitative Genetic Parameters

Abstract Pearl millet [Pennisetum glaucum (L.) R. Br.] is an important food-security crop to smallholder farmers in West Africa (WA). Breeding for high yield and stability is a major challenge in the harsh environments of WA but could be tackled by hybrid breeding. Knowledge of combining ability patterns and quantitative-genetic parameters is required for an efficient development of hybrid varieties. Hence, our objectives were to estimate the combining ability of seven genetically diverse Sahelian pearl millet populations from Senegal, Mali, Benin, Burkina Faso, Niger, Sudan and Nigeria and the heterosis and stability of their 42 diallel-derived population hybrids to inform pearl millet hybrid breeding. The genotypes were evaluated in six environments in WA in 2007. Grain yield (GY) exhibited an average panmictic mid-parent heterosis (PMPH) of 24%, ranging from -1.51% to 64.69%. General combining ability (GCA) was significant across test environments as reflected by high heritability estimates and high GCA:SCA variance ratios. Thus, early selection for parental per se performance would be rewarding. The parental population from Sudan (IP8679) had strongly negative GCA for GY. Its lack of adaptation contributed to the predominance of additive effects in the present germplasm set. Parental populations PE02987 (Senegal), PE05344 (Mali) and ICMV IS 92222 (Niger) showed large positive GCA for GY. Their offspring, especially PE02987 × PE05344 and Kapelga × ICMV IS 92222, exhibited a high and stable GY across all test environments. Tapping the regional pearl millet genetic diversity seems therefore beneficial for hybrid breeding to increase pearl millet productivity in WA.

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Use of F2 bulks in training sets for genomic prediction of combining ability and hybrid performance

10.1101/501916 ◽

2018 ◽

Author(s):

Frank Technow

Keyword(s):

Genomic Prediction ◽

Combining Ability ◽

Hybrid Breeding ◽

Hybrid Performance ◽

Crop Species ◽

Heterotic Groups ◽

Quantitative Genetic ◽

Hand Pollination ◽

ABSTRACTDeveloping training sets for genomic prediction in hybrid crops requires producing hybrid seed for a large number of entries. In autogamous crop species (e.g., wheat, rice, rapeseed, cotton) this requires elaborate hybridization systems to prevent self-pollination and presents a significant impediment to the implementation of hybrid breeding in general and genomic selection in particular. An alternative to F1 hybrids are bulks of F2 seed from selfed F1 plants (F1:2). Seed production for F1:2 bulks requires no hybridization system because the number of F1 plants needed for producing enough F1:2 seed for multi-environment testing can be generated by hand-pollination. This study evaluated the suitability of F1:2 bulks for use in training sets for genomic prediction of F1 level general combining ability and hybrid performance, under different degrees of divergence between heterotic groups and modes of gene action, using quantitative genetic theory and simulation of a genomic prediction experiment. The simulation, backed by theory, showed that F1:2 training sets are expected to have a lower prediction accuracy relative to F1 training sets, particularly when heterotic groups have strongly diverged. The accuracy penalty, however, was only modest and mostly because of a lower heritability, rather than because of a difference in F1 and F1:2 genetic values. It is concluded that resorting to F1:2 bulks is, in theory at least, a promising approach to remove the significant complication of a hybridization system from the breeding process.

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PREDICTION OF COMBINING ABILITY AND HETEROSIS IN THE SELECTED PARENTS AND HYBRIDS IN RICE (Oryza Sativa.L)

Informatika Pertanian ◽

10.21082/ip.v26n1.2017.p31-40 ◽

2017 ◽

Vol 26 (1) ◽

pp. 31

Author(s):

Yuni Widyastuti

Keyword(s):

Grain Yield ◽

Combining Ability ◽

Block Design ◽

Hybrid Breeding ◽

Field Station ◽

Yield Trait ◽

Good Potential ◽

Parental Lines ◽

<p>Selection of parents based on their combining ability is an effective approach in hybrid breeding. Four CMS and four restorer lines were crossed in line x tester mating design to obtain 16 F1 hybrids rice. The 8 parental lines and 16 hybrids rice were planted in randomized complete block design with three replications at Kuningan and Muara field station of ICRR during 2012-2013. The results revealed that mean squares for GCA were significant for number of fertile spikelet per panicle, a thousand-grains weight, and 50% days of flowering. Mean squares for SCA were significant for plant height and grain yield. Parental lines exhibited the highest GCA effects for GMJ12A (line) and CRS703 (tester) for grain yield trait and revealed good potential to be used as parents for hybrid rice. Among all the crosses, GMJ6A/CRS707 and GMJ12A/CRS707 showed the greatest positive SCA effects for grain yield and had heterosis over better parent and midparent.</p>

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Combining ability and heterosis in plant improvement

Open Journal of Plant Science ◽

10.17352/ojps.000043 ◽

2021 ◽

pp. 108-117

Author(s):

Begna Temesgen

Keyword(s):

Genetic Diversity ◽

Combining Ability ◽

Crop Improvement ◽

Critical Factor ◽

Hybrid Vigor ◽

Hybrid Breeding ◽

Crop Species ◽

Heterotic Groups

Information on combining ability and heterosis of parents and crossings is crucial in breeding efforts. Genetic variety is crucial to the effectiveness of yield improvement efforts because it helps to broaden gene pools in any given crop population. The genotype's ability to pass the intended character to the offspring is referred to as combining ability. As a result, information on combining ability is required to determine the crossing pairs in the production of hybrid varieties. Heterosis is the expression of an F1 hybrid's dominance over its parents in a given feature, as measured not by the trait's absolute value, but by its practical use. To put it another way, heterosis is defined as an increase in the character value of F1 hybrids when compared to the average value of both parents. A plant breeder's ultimate goal is to achieve desirable heterosis (hybrid vigor). In a variety of crop species, heterosis has been widely employed to boost output and extend the adaptability of hybrid types. A crucial requirement for discovering crosses with significant levels of exploitable heterosis is knowledge of the quantity of heterosis in different cross combinations. Any crop improvement program's success is contingent on the presence of a significant level of genetic diversity and heritability. The lack of a broad genetic foundation is the most significant constraint to crop improvement and a major bottleneck in breeding operations. Heterosis is a critical factor in hybrid generation, particularly for traits driven by non-additive gene activity. To get the most out of heterosis for hybrid cultivar production, germplasm must be divided into distinct heterotic groups. Similarly, knowledge on genetic diversity is critical for hybrid breeding and population improvement initiatives because it allows them to analyze genetic diversity, characterize germplasm, and categorize it into different heterotic groupings. In general, general combining ability is used to detect a line's average performance in a hybrid combination, whereas specific combining ability is used to find circumstances where definite combinations perform better or worse than expected based on the mean performance of the lines involved.

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Integrated Isoform Sequencing and Dynamic Transcriptome Analysis Reveals Diverse Transcripts Responsible for Low Temperature Stress at Anther Meiosis Stage in Rice

Frontiers in Plant Science ◽

10.3389/fpls.2021.795834 ◽

2021 ◽

Vol 12 ◽

Author(s):

Zhaojun Qu ◽

Yan Jia ◽

Yuyang Duan ◽

Hongyang Chen ◽

Xinpeng Wang ◽

...

Keyword(s):

Low Temperature ◽

Cold Stress ◽

Cold Tolerance ◽

Temperature Stress ◽

Expression Profiles ◽

Pollen Viability ◽

Enrichment Analysis ◽

Pollen Sterility ◽

Low Temperature Stress ◽

Amino Acid Contents

Low temperatures stress is one of the important factors limiting rice yield, especially during rice anther development, and can cause pollen sterility and decrease grain yield. In our study, low-temperature stress decreased pollen viability and spikelet fertility by affecting the sugar, nitrogen and amino acid contents of anthers. We performed RNA-seq and ISO-seq experiments to study the genome-wide transcript expression profiles in low-temperature anthers. A total of 4,859 differentially expressed transcripts were detected between the low-temperature and control groups. Gene ontology enrichment analysis revealed significant terms related to cold tolerance. Hexokinase and glutamate decarboxylase participating in starch and sucrose metabolism may play important roles in the response to cold stress. Using weighted gene co-expression network analysis, nine hub transcripts were found that could improve cold tolerance throughout the meiosis period of rice: Os02t0219000-01 (interferon-related developmental regulator protein), Os01t0218350-00 (tetratricopeptide repeat-containing thioredoxin), Os08t0197700-00 (luminal-binding protein 5), Os11t0200000-01 (histone deacetylase 19), Os03t0758700-01 (WD40 repeat domain-containing protein), Os06t0220500-01 (7-deoxyloganetin glucosyltransferase), Pacbio.T01382 (sucrose synthase 1), Os01t0172400-01 (phospholipase D alpha 1), and Os01t0261200-01 (NAC domain-containing protein 74). In the PPI network, the protein minichromosome maintenance 4 (MCM4) may play an important role in DNA replication induced by cold stress.

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Heritability and Combining Ability Studies in Strawberry Population

Journal of Agricultural Science ◽

10.5539/jas.v11n4p457 ◽

2019 ◽

Vol 11 (4) ◽

pp. 457 ◽

Author(s):

Sylvia D. Vieira ◽

Ana L. R. Araujo ◽

Douglas C. Souza ◽

Luciane V. Resende ◽

Monik E. Leite ◽

...

Keyword(s):

Combining Ability ◽

Crop Improvement ◽

Genetic Correlations ◽

Fruit Production ◽

Hybrid Population ◽

Phenotypic Variance ◽

F1 Hybrid ◽

Physical And Chemical Quality ◽

Efficient Breeding

The most efficient breeding strategies in crop improvement is the selection based on heritability and combing ability estimates for the traits of economic importance or commercial value. Therefore, the present study was to obtain estimates of heritability and to estimate the phenotypic and genotypic correlations among the characteristics of interest. The commercial cultivars ‘Aromas’, ‘Camarosa’, ‘Dover’, ‘Festival Flórida’, ‘Oso Grande’, ‘Sweet Charlie’ and ‘Milsei-Tudla’, and 103 F1 hybrids from the crossbreeding experiments were evaluated for four traits of commercial fruit yield and 13 traits of fruit physical and chemical quality. The estimated genetic parameters were general combining ability, specific combining ability, genotypic correlation among traits, estimates of heritability, genetic and phenotypic variance. The ‘Camarosa’ and ‘Aromas’ cultivars were the most promising cultivars for use as parents in the commercial fruit production, while ‘Dover’ and ‘Sweet Charlie’ cultivars were selected for taste of fruit in strawberry breeding, as they showed higher concentrations of favorable alleles in the F1 hybrid population. It was also verified some strong genetic correlations for some pairs of characteristics in the present study that may allow indirect selection. The estimation of these parameters is an important basis for decision making on the genetic engineering of strawberry.

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Heterosis and combining abilities in a diverse seven-parent pearl millet population diallel tested in West Africa

Euphytica ◽

10.1007/s10681-021-02939-0 ◽

2021 ◽

Vol 217 (12) ◽

Author(s):

Sonali Dutta ◽

Felix T. Sattler ◽

Anna Pucher ◽

Inoussa Drabo ◽

Ahmad Issaka ◽

...

Keyword(s):

West Africa ◽

Pearl Millet ◽

Combining Ability ◽

Pennisetum Glaucum ◽

Smallholder Farmers ◽

Hybrid Vigor ◽

Hybrid Breeding ◽

Variance Ratios ◽

High Heritability

AbstractPearl millet [Pennisetum glaucum (L.) R. Br.] is an important food-security crop to smallholder farmers in West Africa (WA). Breeding for high yield and stability is a major challenge in the harsh environments of WA but could be tackled by a more systematic exploitation of hybrid vigor and heterosis in breeding of both open-pollinated varieties (OPVs) and different types of hybrids. Knowledge of combining ability patterns and quantitative-genetic parameters is required for an efficient development of hybrid vigor and heterosis in breeding programs. Hence, our objectives were to complement other existing studies and estimate the combining ability of seven unique, highly diverse Sahelian pearl millet populations from Senegal, Mali, Benin, Burkina Faso, Niger, Sudan and Nigeria and the heterosis and stability of their 42 diallel-derived population hybrids (or hybrid populations) to inform pearl millet OPV and hybrid breeding. The materials were evaluated in six environments in WA in 2007. Grain yield (GY) exhibited an average panmictic mid-parent heterosis of 24%, ranging from − 1.51 to 64.69%. General combining ability (GCA) was significant across test environments as reflected by high heritability estimates and high GCA:SCA variance ratios. Thus, early selection for parental per se performance would be rewarding. The parental population from Sudan (IP8679) had strongly negative GCA for GY. Its lack of adaptation contributed to the predominance of additive effects in the present germplasm set. Parental populations PE02987 (Senegal), PE05344 (Mali) and ICMV IS 92222 (Niger) showed large positive GCA for GY. Their offspring, especially PE02987 × PE05344 and Kapelga × ICMV IS 92222, exhibited a high and stable GY across all test environments. Tapping the regional pearl millet genetic diversity and preselecting the crossing parents seem beneficial for OPV and hybrid breeding to increase pearl millet productivity in WA.

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