Preprint Review Version 2 Preserved in Portico This version is not peer-reviewed

Induced Polyploidy: A Tool for Forage Species Improvement

Version 1 : Received: 5 January 2021 / Approved: 6 January 2021 / Online: 6 January 2021 (11:10:40 CET)
Version 2 : Received: 22 February 2021 / Approved: 23 February 2021 / Online: 23 February 2021 (14:25:28 CET)

How to cite: Rauf, S.; Ortiz, R.; Malinowski, D.; Clarindo, W.; Kainat, W.; Shehzad, M.; Waheed, U.; Hassan, S.W. Induced Polyploidy: A Tool for Forage Species Improvement. Preprints 2021, 2021010110 (doi: 10.20944/preprints202101.0110.v2). Rauf, S.; Ortiz, R.; Malinowski, D.; Clarindo, W.; Kainat, W.; Shehzad, M.; Waheed, U.; Hassan, S.W. Induced Polyploidy: A Tool for Forage Species Improvement. Preprints 2021, 2021010110 (doi: 10.20944/preprints202101.0110.v2).

Abstract

Polyploidy means having more than two basic sets of chromosomes. Polyploid plants may be artificially obtained through chemical, physical and biological (2n gametes) methods. This approach allows an increased gene scope and expression, thus resulting in phenotypic changes such as yield and product quality. Nonetheless, breeding new cultivars through induced polyploidy should overcome deleterious effects that are partly contributed by genome and epigenome instability after polyploidization. Furthermore, shortening the time required from early chromosome set doubling to the final selection of high yielding superior polyploids is a must. Despite these hurdles, plant breeders have successfully obtained polyploid bred-germplasm in broad range of forages after optimizing methods, concentration and time, particularly when using colchicine. These experimental polyploids are a valuable tool for understanding gene expression, which seems to be driven by dosage dependent gene expression, altered gene regulation and epigenetic changes. Isozymes and DNA-based markers facilitated the identification of rare alleles for particular loci when compared with diploids, and also explained their heterozygosity, phenotypic plasticity and adaptability to diverse environments. Experimentally induced polyploid germplasm could enhance fresh herbage yield and quality, e.g. leaf protein content, leaf total soluble solids, water soluble carbohydrates and sucrose content. Offspring of experimentally obtained hybrids should undergo selection for several generations to improve their performance and stability.

Subject Areas

Amphiploidy; Disomic Polyploidy; Plant Genome Evolution; Neo-polyploidy; Polysomic Polyploidy

Comments (1)

Comment 1
Received: 23 February 2021
Commenter: Rodomiro Ortiz
Commenter's Conflict of Interests: Author
Comment: 1. Title changed 

Induced polyploidy: A tool for forage species improvement

2. Following paragraph has been added in the conclusion section along with some minor changes.

A careful selection of anti-tubulin agent and its optimum concentration may be required to increase the frequency of successful polyploids with less deleterious mutations. DNA markers may be used for background selection to accurately select genotypes with lesser mutagenic effects. Confirmation of induced polyploid with balanced chromosome pairing (bivalent or quadrivalent) may be necessary, although it has been cumbersome through empirical methods. Flow cytometry is an alternative tool for confirmation of duplicated genome size. However, judging chromosomal pairing behavior may require pachytene analysis. Stability testing of induced hybrids under various agroclimatic conditions may be undertaken to accurately estimate the superiority of induced polyploids over the related diploids.   

3. Term neo-polyploid has been replaced by induced polyploid to unify the term through out text

4. A reference # 41 text added at line number 283 and 287

[41] = Comai, L. The advantages and disadvantages of being polyploid. Nat. Rev. Genet., 2005, 6, 836–846.

5. New statement added in Line 951

Chromosome number counting was done in various generation following induced polyploid

+ Respond to this comment

We encourage comments and feedback from a broad range of readers. See criteria for comments and our diversity statement.

Leave a public comment
Send a private comment to the author(s)
Views 0
Downloads 0
Comments 1
Metrics 0


×
Alerts
Notify me about updates to this article or when a peer-reviewed version is published.
We use cookies on our website to ensure you get the best experience.
Read more about our cookies here.