1. Morphological and Physiological Traits⌂ Home

1.1. Gross Morphology: Spike characteristics⌂ Home

Major hexaploid wheat types are categorized into groups with respect to three major gene pairs; viz. Q, C and S1 {1038}.

1. Common wheat Q c S1 v: vulgare group.

2. Club wheat Q C S1 v: compactum group.

3. Shot wheat Q c s1 v: sphaerococcum group.

4. Spelt wheat q c S1 and q C S1 v: spelta group (including vavilovi).

The majority of hexaploid wheat stocks are already, or can be readily, classified into these groups. Diploid wheat is assumed to be q. Durum and carthlicum groups have the genotype Q {1049}.

Q

C

S1

S2

1.2. Branched spike⌂ Home

Synonyms: branched spike, four-rowed spike, multi-rowed spike, supernumerary spikelet, tetrastichon spikelet.

Branched spike and multi-rowed spike are phenotypes involving the presence of supernumerary spikelets,

or the presence of additional spikelets at rachis nodes. A similar condition in rye is known as 'monstrosum ear' (reviewed in {10637}). Genetic studies of branched spike in tetraploid and hexaploid wheats indicate that the phenotype is recessive, involves one or more genes, and is strongly influenced by environmental effects. Comparative genetic studies suggest an orthologous gene series in homoeologous group 2 {10637}.

BH1

1.3. Elongated glume⌂ Home

Elongated glume is the phenotype associated with the polonicum group of tetraploid wheats. Expression in hexaploid wheat is much reduced compared with tetraploids. Matsumura {911} reported linkage of gene P and a gene for red coleoptiles implicating chromosomes 7A or 7B. A different gene was subsequently located in chromosome 7B {9990}.

P1

1.4. Ear length⌂ Home

1.5. Multi-gynoecium; Multi-ovary⌂ Home

Synonym: three pistils (TP).

This trait describes a dominant phenotype consisting of 3 kernels within each wheat floret; that is, the flower consists of 3 separate ovaries, 3 anthers and 2 lodicules.

PIS1

1.7. Alkylresocinol content in grain⌂ Home

AR

1.8. Aluminium tolerance⌂ Home

ALT1

ALT2

1.9. Anthocyanin pigmentation⌂ Home

The genetic determinants of anthocyanin pigmentation of various tissues are largely located in homoeologous regions in group 7, viz. 7BS ( Rc-B1, Pc-B1, Plb-B1, Pls-B1 ) and 7DS ( Rc-D1, Pc-d1, PlbD1 ), and appear to be linked clusters rather than multiple alleles on each chromosome {10700}. Their relationship with genes for purple auricle and purple pericarp are still not clear.

PAN

RC1

RC-B1

RC-D1

PC1

PC2

PP1

PP2

PP3

PG

PLB

1.10. Awnedness⌂ Home

In cereals such as barley and rice awns are conferred by dominant genes. No homologous genes have been reported in wheat.

HD

B1

B2

1.12. Blue Aleurone⌂ Home

The Ba allele in T. monococcum spp. aegilopoides acc. G3116 determines a half-blue seed phenotype and is different from the allele present in Elytrigia pontica that determines a solid blue phenotype {282}. They are treated as different genes.

For review see {1643}.

BA1

BA2

1.13. Brittle culm⌂ Home

Three independent mutants with brittle tissues were obtained as EMS-induced mutants in T. monococcum accessions PAU 14087 {11002}. The mutations likely affected cellulose synthesis and involved all tissues {11002}.

BRC1

BRC2

BRC3

1.14. Brittle rachis⌂ Home

Brittle rachis in T. durum was defined as a spike that disarticulated when the tip was bent by 45 degrees relative to the peduncle {10242}. In chromosome substitution lines of wild emmer to common wheat, the 3AS derivative was more brittle than the 3BS derivative {10974}.

Wedge (W) type disarticulation is associated with the Br-1 gene set whereas barrel (B) type disarticulation is caused by a different gene and is limited to species with the D genome {11080}.

BR-A1

BR-B1

BR-D1

BR-S1

Br-D2

BR4

1.15. Boron tolerance⌂ Home

Genes controlling tolerance to high concentrations of soil boron act additively.

BO1

BO2

BO3

BO4

1.16. Cadmium Uptake⌂ Home

Low uptake is dominant.

CDU1

1.17. Chlorophyll abnormalities⌂ Home

V1

V2

CN1

1.18. Cleistogamous flowering⌂ Home

Cleisogamy in barley is controlled by the Chy1 allele that encodes an AP2 protein. The Cly and cly1 alleles differ by a single nucleotide within the miR172 binding site. Three wheat homologues of Cly1, viz, TaAP-2A, TaAp-2B and TaAp-2D were located in the terminal bins of chromosomes 2AL, 2BL and 2DL, respectively in Chinese Spring and Shinchunaga {11013}. Cleistogamous flowering in durums Cleistogamy, a rare flowering habit in durum wheats, is controlled by a single recessive gene relative to chasmogamy {191}.

CL

1.19. Copper efficiency⌂ Home

Copper efficiency is a genetic attribute that enhances plant growth in copper deficient soil.

CE

1.20. Corroded⌂ Home

CO1

CO2

1.21. Crossability with Rye and Hordeum and Aegilops Spp.⌂ Home

KR1

KR2

KR4

KR5

1.22. Dormancy (Seed)⌂ Home

Seed dormancy in wheat has several components, including factors associated with vivipary and red grain colour. Dormancy is an important component of resistance/tolerance to pre-harvest sprouting (PHS). For a review of genes involved in preharvest sprouting see {11569}.

TaSDR-1

VP-1

1.23. Ear emergence⌂ Home

1.24. Earliness per se⌂ Home

Genes for earliness per se {0023} affect aspects of developmental rate that are independent of responses to vernalization and photoperiod.

EPS-A1

EPS-B1

EPS-D1

1.27. Flowering time⌂ Home

The isolation of wheat genes orthologous to the Arabidopsis Co and rice Hd1 genes was reported in {10054}. The genomic clones TaHd1-1, TaHd1-2 and TaHd1-3 originated from the long arms of chromosomes 6A, 6B and 6D, respectively. The orthology of the TadHd1 genes with Co/Hd1 was demonstrated by complementation of a rice line deficient in Hd1 function with the TaHd1-1 genomic clone. The wheat TaHd1 and rice Hd1 genes were located in non-syntenic locations {10054}. To date, no variation for flowering time has been identified on wheat group 6 chromosomes.

1.28. Flour colour⌂ Home

Schomburgk/Yarralinka: RIL population: Regions in 3A and 7A accounted for 13% and 60% of the genetic variation, respectively, and Xbcd828-3A , Xcdo347-7A and Xwg232-7A.1 were significantly associated with flour colour {9936}. The association was highly significant in all three replicates only for the 7A QTL. Symbols were not assigned to the flour colour loci. See also 29.2. Flour, semolina and pasta colour. Lutein is one of the carotenoids contributing to flour colour. Esterification of lutein contributes to its stability during storage. A locus controlling esterification was located in chromosome 7D.

Lutein esterification

LUTE

1.29. Free-threshing habit⌂ Home

1.30. Frost resistance⌂ Home

FR-1

FR-2

1.31. Gametocidal genes and segregation distortion⌂ Home

GC1-B1

GC1-C1

GC2-S[l] 1

GC-C1

IGC1

SD1

SD2

1.32. Gibberellic acid response (insensitivity)⌂ Home

GAI1

GAI2

GAI3

1.33. Glaucousness (Waxiness/Glossiness)⌂ Home

The W loci are complexes of closely linked genes involved in beta-diketone synthesis.

Glaucousness refers to the whitish, wax-like deposits that occur on the stem and leaf-sheath surfaces of many graminaceous species. The expression of glaucousness depends on the arrangement of wax deposits rather than the amount of wax {603}. Non-glaucous variants also occur and genetic studies indicate that non-glaucousness can be either recessive or dominant. Recessive forms of non-glaucousness are apparently mutants of the genes that produce the wax-like deposits. Dominant non-glaucous phenotypes (as assessed visually) appear to be due to mutations that affect the molecular structure, and reflectance, of the wax-like substances {10001}. The genes involved in wax production and the "inhibitors" are duplicated in chromosomes 2B and 2D. There appear to be independant genes for wax production and "inhibitors" {912}, {1493}, {10001}. In earlier issues of the gene catalogue the two kinds of genes were treated as multiple alleles {1432}. All forms of wild and cultivated einkorn are non-glaucous {10001}. Orthologous loci occur in barley chromosome 2HS ( gs1, gs6, gs8 ) {467}, rye chromosome 7RL ( wa1 ) {725} and maize ( gl2 ) {211}. A gene for spike glaucousness, Ws , was mapped distally on chromosome 1BS in the cross T. durum cv. Langdon / T. dicoccoides acc. Hermon H52 {0171}.

W2

W3

IW

IW2

IW3

WS

1.34. Glume colour and awn colour⌂ Home

RG-A1

PBC

CC

BLA1

1.35. Grain Hardness/Endosperm Texture⌂ Home

Grain hardness or endosperm texture significantly influences flour milling, flour properties and end-use. The difference in particle size index between a hard wheat (Falcon) and a soft wheat (Heron) was reported by Symes {1452} to be due to a single major gene. Symes {1452} also found evidence for "different major genes or alleles" which explained differences amongst the hard wheats Falcon, Gabo and Spica. Using Cheyenne (CNN) substitution lines in CS and a Brabender laboratory mill, Mattern et al. {915} showed that the hard wheat milling and flour properties of Cheyenne were associated with 5D. Using Hope 5D substitution line in CS [CS(Hope 5D)] crossed to CS, and CS(Hope 5D) crossed to CS ditelosomic 5DL, Law et al. {777} showed that grain hardness was controlled by alleles at a single locus on 5DS. The dominant allele, Ha , controlling softness was present in Chinese Spring and the allele for hardness, ha , was present in the others. A similar study using CS (CNN5D)/CS recombinant inbred lines was reported by Morris et al. {03106}.

A pleiotropic result of hardness is the decreased level of a 15 kD starch granule protein, friabilin, on the surface of water-isolated starch {470}. In endosperm, soft and hard wheats have similar amounts of friabilin, consequently the distinction between the two textural types depends upon the manner in which the friabilin co-purifies with starch. Friabilin is also referred to by the name 'Grain Softness Protein' (GSP) {0384}, and was later shown to be comprised primarily of puroindoline a and puroindoline b {0295}. Grain hardness of reciprocal soft x hard F1 kernels was well correlated with friabilin occurrence on starch in triploid endosperm {0381}. See IV, Proteins: 5.8 Puroindoline. GSP-1 genes, which are closely related to puroindolines, are also listed in the Protein section.

HA

1.36. Grain quality parameters⌂ Home

LVL

TaBAS1

TaGASR

TaGS1

TaGW

TaSAP1

TaTGW-7A

TaTGW-A1

TaTGW6

1.38. Grass-clump dwarfness/Grass dwarfness⌂ Home

Complementary dominant genes. Genotypes producing dwarfness: D1-D2-D3-, D1-D2D2, D1-D4-D3-, D1-D2-D4 and D1-D4D4 .

D1

D2

D3

D4

1.40. Hairiness/Pubescence traits⌂ Home

PA

HG1

HG2

HL1

HL2

HS

HP

HN

1.42. Reduced height⌂ Home

RHT-A1

RHT-B1

RHT-D1

RHT4

RHT6

RHT7

RHT9

RHT11

RHT13

RHT14

RHT15

RHT16

RHT17

RHT18

RHT19

RHT20

RHT21

RHT22

RHT23

In Renan / Recital:

1.43. Herbicide Response⌂ Home

DFQ1

SU1

IMI1

IMI2

IMI3

1.44. Hybrid Weakness⌂ Home

NE1

CH1

CH2

CS1

CS2

NEC1

1.45. Iron deficiency⌂ Home

1.46. Lack of ligules⌂ Home

The liguleless character is controlled by complementary recessive genes in hexaploid wheat {077}, {738}, {942} and by a single recessive in tetraploid wheat {047}, {050}, {939}, {10133}. One gene at the tetraploid level is allelic with one of those in the hexaploid {939}, {10133}. Evidence for orthology of lg1 and lg2 with lg of rice {170}, lg1 of maize {004}, li of barley {1155} and al of rye was presented in {725}. An Imperial rye chromosome 2R addition restored the liguled condition to a liguleless CS derivative {939}. An erect leaf mutant involving TaSPL8 (SQUAMOSA promoter-binding protein-like transcription factor), a homolog of LG1 in maize and rice and was located in chromosome 2D. Knockout mutants of TaSPL8 orthologs led to a fully liguleless phenotype. The gene in 2D was identified as TraesCS2D01G502900. TaSPL8 transcript was highly expressed in the laminar joint region and young spike. TaSPL8- 2D transcript was produced at much higher levels than TaAPL-2B whereas TaSPL-2A was produced at a minimal level {11401}.

LG1

LG3

1.47. Leaf characteristics⌂ Home

LTN1

LTN2

LTN3

SC

ELS1

ELS2

1.48. Lesion Mimicry⌂ Home

Add introductory sentence: Lesion mimic phenotypes are characterised by spontaneous hypersensitivity not unlike disease resistance. Lesions are often not produced when leaf sectors are protected from light, and disease levels on mutant individuals may be lower than on non-mutant sibs. Lesion mimics that resemble the response of plants to infection by pathogens occur in many species ({10743} for examples).

LM

LM1 and LM2

1.49. Lodging⌂ Home

1.50. Male sterility⌂ Home