triticale

Triticale (× Triticosecale ) / t r ɪ t ɪ k eɪ the i / is a hybrid of wheat ( Triti cum ) and rye ( If wedge ) first bred in laboratories During the late 19th century in Scotland and Germany . 

^[1]Commercially available triticale is almost always a second-generation hybrid, ie, a cross between two kinds of primary (first-cross) triticales. As a rule, triticale combines the yield potential andgrain quality of wheat with the disease and environmental tolerance (including soil conditions) of rye. Only recently has been developed into a commercially viable crop. Depending on the cultivar , triticale can more or less resemble of its parents. It is grown mostly for drilling or fodder , ALTHOUGH Some triticale-based foods can be purchased this at health food stores and can be found in Some breakfast cereals .

When crossing wheat and rye, wheat is used as the female parent and rye as the male parent (pollen donor). The resulting hybrid is sterile and must be treated with colchicine to induce polyploidy and thus the ability to reproduce itself.

The primary producers of triticale are Poland , Germany , Belarus , France and Russia . In 2014, according to the Food and Agriculture Organization (FAO), 17.1 million tones were harvested in 37 countries across the world. ^[2]

The triticale hybrids are all amphidiploid , qui means clustering the plant is diploid for two genomes derived from different species . In other words, triticale is an allotetraploid . In earlier years, most work was done on triticale octoploid . Different ploidy levels have been created and evaluated over time. The tetraploids showed little promise, triticale hexaploid goal was successful enough to find commercial application. ^[3]

The International Maize and Wheat Improvement Center triticale improvement program Was Intended to Improve Food Production and Nutrition in Developing Countries . Triticale was thought to have potential in the production of bread and other food products, such as cookies , pasta , pizza dough and breakfast cereals . ^[3] The protein content is higher than that of wheat, but the glutenin fraction is less. The grain has been reported to have higher levels of lysine than wheat. ^[4] Acceptance would require the millingindustry to adapt to triticale, the techniques employed for wheat are unsuited to triticale. Sell et al. ^[5] found triticale could be used as a feed grain, and later researches its starch was particularly readily digested. ^[6] As a grain feed, triticale is already established and of high economic importance. It has received attention as a potential energy crop , and research is being conducted on the use of biomass in bioethanol production.

Species

Triticale hybrids include: ^[7]

• × Triticosecale blaringhemii A.Camus
• × Triticosecale neoblaringhemii A.Camus
• × Triticosecale schlanstedtense Wittm.
• × Triticosecale semisecale (Mackey) K.Hammer & Filat.

Biology and genetics

Earlier work with wheat-rye crosses was difficult to achieve with a result of hybrid embryo and spontaneous chromosome doubling. These two factors were difficult to predict and control. To improve the viability of the embryo and thus avoid its abortion, in vitro culture techniques were developed (Laibach, 1925) ^{[ full citation needed ]} . Colchicine was used as a chemical agent to double the chromosomes (Blakeslee & Avery, 1937-12-01, “Methods of Inducing Doubling of Chromosomes in Plants”, Journal of Heredity, https://doi.org/10.1093/oxfordjournals.jhered .a104294 ) ^{[ full quote needed ]}. After these developments, a new era of triticale breeding was introduced. Earlier triticale hybrids HAD reproductive disorders oven-Namely, meiotic instability, high aneuploid frequency, low fertility and shriveled seed (Müntzing 1939 Krolow 1966) ^{[ full citation needed ]} . Cytogenetical studies have been encouraged to overcome these problems.

It is especially difficult to see the expression of the genes in the cytoplasm and the predominant wheat genome . This makes it difficult to achieve the potential of rye in disease resistance and ecological adaptation. One of the ways to relieve this problem is to produce dry , in which rye cytoplasm was used instead of that from wheat.

Triticale is essentially a self-fertilizing, or naturally inbred , crop. This mode of reproduction results in a more homozygous genome. The crop is, however, adapted to this form of reproduction from an evolutionary point of view. Cross-fertilization is also possible, but it is not the primary form of reproduction.

Conventional breeding approaches

Top Triticale producers in 2014
(million metric tons)
poland	5.2
germany	3.0
belarus	2.1
la France	2.0
russia	0.7
china	0.5
hungary	0.5
spain	0.4
lithuania	0.4
austria	0.3
Total World	17.1
Source: UN Food & Agriculture Organization (FAO) [1]

The aim of a triticale breeding program is primarily focused on the improvement of quantitative traits , such as grain yield, nutritional quality, and plant height, which are more difficult to improve, of bulk density). These traits are controlled by more than one gene . ^[8] Problems arise, however, because such polygenic traits involve the integration of several physiological processes in their expression. Thus the lack of single-gene control (or simple inheritance) results in low trait heritability (Zumelzú et al., 1998).

Since the induction of the CIMMYT triticale breeding program in 1964, the yield has been remarkable. In 1968, at Ciudad Obregón , Sonora , in northwest Mexico , the highest yielding triticale line produced 2.4 t / ha. Today, CIMMYT has released high yielding spring triticale lines (eg Pollmer-2) which have surpassed the 10 t / ha yield barrier under optimum production conditions. ^[9]

Based on the success of other hybrid crops, the use of hybrid triticale Earlier research conducted by CIMMYT made use of a chemical hybridization agent to evaluate heterosis in hexaploidtriticale hybrids. The most promising parents for hybrid production, test crosses in various environments are required, because the variance of their specificity is one of the most important components of their potential parenting process. The prediction of general breeding ability of any triticale plant from the performance of its parents is only moderate with respect to grain yield. Commercially exploitable yield advantages of hybrid triticale cultivars are dependent on improving parent heterosis and inbred -line development.

Triticale is useful as an animal feed grain . However, it is necessary to improve its milling and bread-making quality aspects to increase its potential for human consumption. The relationship entre les are wheat and rye genomes Were Noted Irregularities to Produce meiotic, and genome instability and incompatibility problems presented Numerous When Attempts Were Made to Improve triticale. Reproductive health performance, namely, the improvement of the number of grains per floral spikelet and its meiotic behavior. The number of grains per spikelet has an associated low heritabilityvalue (de Zumelzú et al., 1998). In improving yield, the indirect selection (the selection of correlated / related features other than that to be improved) is not necessary. (Gallais 1984) ^[10]

Lodging is a complexly inherited trait, which is a complexly inherited trait. ^[11] The use of dwarfing genes, known as Rht genes, which have been incorporated by Triticum and Secale , has resulted in a decrease of up to 20 cm in plant height without any adverse effect.

Application of newer techniques

Abundant information exists concerning disease resistance (R) genes for wheat, and a continually updated on-line catalog, the Catalog of Gene Symbols, of these genes can be found at [2] . Another on-line database of cerealresistance genes is available at [3] . Unfortunately, it is known about rye and particularly triticale R-genes. Many R-genes have appeared in the catalog, thus making them available for triticale breeding. The two mentioned databases are important contributors to improving the genetic diversity of the triticale gene poolthrough gene (or more specifically, allele) provision. Genetic variability is essential for progress in breeding. In addition, genetic variability can be achieved by producing new primary triticales, which essentially constitutes the reconstitution of triticale, and the development of various hybridities involving triticale, such as triticale-rye hybrids. In this way, some chromosomes from the genome have been replaced by some genome. The resulting so-called substitution and triticale translocation facilitates the transfer of R-genes.

Introgression

Introgression involves the crossing of closely related plants, and results in the transfer of ‘blocks’ of genes, ie larger segments of chromosomes compared to single genes. R-genes are generally introduced within such blocks, which are usually incorporated / translocated / introgressed into the distal (extreme) regions of the chromosomes of the crop being introgressed. Genes located in the proximal areas of chromosomes may be completely linked, thus preventing or severely hampering genetic recombination , which is necessary to incorporate such blocks. ^[12] Molecular markers (small lengths of DNA of a known / known sequence) are used to ‘tag’ and thus track such translocations. ^[13]A weak colchicine solution has been employed to increase the probability of recombination in the proximal chromosome regions, and thus the introduction of the translocation to that region. The result translocated smaller blocks that actually carry the R-gene (s) of interest has decreased the probability of introducing unwanted genes. ^[14]

Production of doubled haploids

Doubled haploid (DH) plants have the potential to save much time in the development of inbred lines. This is achieved in a single generation, as opposed to many, which would otherwise occupy much physical space / facilities. DHs aussi express deleterious recessive alleles Otherwise masked by dominance effects in a genome Containing more than one copy of Each chromosome (and THUS more than one button copy of Each gene). Various techniques exist to create DHs. The in vitro culture of anthers and microspores is most often used in cereals , including triticale. ^{[15] [16] [17]}These two techniques are referred to as androgenesis, which refers to the development of pollen . Many plant species and cultivars within species, including triticale, are recalcitrant in that the success rate of all newly generated (diploid) plants is very low. Genotype by medium cultural interaction is responsible for varying, success rates, as is a high degree of microspore abortion During culturing. (Johansson et al. 2000) ^[18] [19] The response of parental triticale lines to anther culture, is Known to be correlated to the response of their progeny. ^{[17] [20] [21]} Chromosome elimination is another method of producing DHs, and involveshybridization of wheat with maize ( Zea mays L.), Followed by auxin treatment and the artificial rescue of the resulting haploid embryos Before They naturally abort. This technique is applied rather extensively to wheat. ^[22] Its success is in large part due to the insensitivity of maize pollen to the crossability inhibitor genes Known As Kr1 and Kr 2 That are Expressed in the floral style of Many wheat cultivars. ^[23] The technique is unfortunately less successful in triticale. ^[24] HOWEVER, Imperata cylindrica (a grass) Was found to be just as effective as maize with respect to the generation of DHs in Bothwheat and triticale. ^[25]

Application of molecular markers

An important advantage of biotechnology applied to plant breeding is the speeding up of cultivar release that would otherwise take 8-12 years. It is the process of selection that is actually enhanced, ie, which is desirable or not desirable. This carries with it the changing structure of the plant population. The website [4] is a valuable resource for marker assisted selection (MAS) related to R-genes in wheat. MAS is a form of indirect selection . The Catalog of Gene Symbols is an additional source of molecularand morphological markers. Again, triticale Has not-been well caractérisé with respect to molecular markers, ALTHOUGH year abundance of rye molecular markers to track Makes It can rye chromosomes and segments thereof Within a triticale background.

Yield improvements of up to 20% have been achieved in hybrid triticale cultivars due to heterosis . ^{[26] [27] [28]} This raises the question of what hybrid lines should produce with hybrid progeny. This is the combined ability of parent lines. The identification of an early successional program in the breeding program can be compared to a large number of plants (literally thousands) through it, and thus forms part of efficient selection. Combining Ability is Assessed by Taking into consideration all available information is descent ( genetic relatedness), morphology, qualitative (simply inherited) traits and biochemical and molecular markers. Exceptionally little information exists on the use of molecular markers to predict heterosis in triticale. ^[29] Molecular markers are generally accepted as predictors of morphological markers of agronomic traits due to their insensitivity to variation in environmental conditions.

A useful molecular marker known as a simple sequence repeat (SSR) is used in breeding with respect to selection. SSRs are segments of a genome composed of tandem repeats of a short sequence of nucleotides , usually two to six base pairs. They are popular tools in relation to their relative abundance compared to other marker types, a high degree of polymorphism (number of variants), and an easy assaying by polymerase chain reaction. However, they are expensive to identify and develop. Comparative genome mapping has revealed a high degree of similarity in terms of sequence. This allows the exchange of such markers within a group of related species, such as wheat, rye and triticale. One study established a 58% and 39% transferability rate to triticale from wheat and rye, respectively. ^[30] Transferability refers to the phenomenon where the sequence of DNA nucleotides flanking the SSR locus (position on the chromosomeis sufficiently homologous (similar) between genomes of closely related species. Thus, DNA primers (a short sequence of nucleotides are used in a copying reaction during PCR) for SSRs in related species. SSR markers are available in wheat and rye, but very few, if any, are available for triticale. ^[30]

Genetic transformation

The genetic transformation of crops involves the incorporation of ‘foreign’ genes or rather, very small DNA fragments compared to introgression. Amongst other uses, transformation is a useful tool to introduce new traits or features into the crop. Two methods are employed: infectious bacterial- medicated (usually Agrobacterium ) and biolistics , with the latter being more common to allopolyploid cereals such as triticale. Agrobacterium- mediated transformation, however, has several advantages, such as a low level of transgenicDNA rearrangement, a low number of copies of the transforming Introduced DNA stable integration of an a priori caractérisée T-DNA fragment (DNA Containing the conjunctival phrase the trait of interest) and expected year Higher Level of transgene expression. Triticale has, until recently, only been transformed via biolistics, with a 3.3% success rate (Zimny et al., 1995). ^[31] Little has-been documented is Agrobacterium -mediated transformation of wheat; while no data existed with respect to triticale until 2005, the success rate is still low. ^[32]

Conclusion

Triticale holds much promise as a commercial crop, as it has the potential to address specific problems within the cereal industry. Research of a high standard is Currently being white Conducted worldwide in places like Stellenbosch University in South Africa .

Conventional plant breeding has been established as a valuable crop, especially where conditions are less favorable for wheat cultivation. Triticale à une synthesized grit et une grain des grains pour les produits et de la production et des primeres.

Tissue culture techniques with respect to wheat and triticale have improved, but the isolation and culturing of microspores seems to be the most promising. Many molecular markers can be applied to marker-assisted gene transfer, but the expression of R-genes in the new genetic background of triticale remains to be investigated. ^[30] More than 750 wheat microsatellite primer peers are available in public wheat breeding programs, and could be exploited in the development of SSRs in triticale. ^[30] Another type of molecular marker, single nucleotide polymorphism (SNP), is likely to have a significant impact on the future of triticale breeding.

Health concerns

Like both its hybrid parents – wheat and rye – triticale contains gluten and is therefore unsuitable for people with gluten-related disorders, such as celiac disease , non-celiac gluten sensitivity and wheat allergy sufferers, among others. ^[33]

Triticale in fiction

An episode of the TV Star Trek series , ” The Trouble With Tribbles, ” which David Gerrold called “quadro-triticale” at producer Gene Coon’s suggestion, and to which he ascribed distinct oven lobes per kernel. A later episode titled ” More Tribbles, More Troubles “, in the animated series , also written by Gerrold, dealt with “quinto-triticale”, an improvement on the original that apparently had five lobes per kernel.

“The Trouble With Tribbles” episode attributed to the development of triticale to Canada. In 1953, the University of Manitoba began the first North American triticale breeding program. Early breeding efforts concentrated on developing a high yielding crop. ^[34]

In the same episode, the character Chekov describes the fictional quadro-triticale as being a “famous Russian invention.”

References