Limits...
A new synthetic allotetraploid (A1A1G2G2) between Gossypium herbaceum and G. australe: bridging for simultaneously transferring favorable genes from these two diploid species into upland cotton.

Liu Q, Chen Y, Chen Y, Wang Y, Chen J, Zhang T, Zhou B - PLoS ONE (2015)

Bottom Line: Creating synthetic allotetraploid cotton from these two species would lay the foundation for simultaneously transferring favorable genes into cultivated tetraploid cotton.Here, we crossed G. herbaceum (as the maternal parent) with G. australe to produce an F1 interspecific hybrid and doubled its chromosome complement with colchicine, successfully generating a synthetic tetraploid.The synthetic allotetraploid will be quite useful for polyploidy evolutionary studies and as a bridge for transferring favorable genes from these two diploid species into Upland cotton through hybridization.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Crop Genetics & Germplasm Enhancement, MOE Hybrid Cotton R&D Engineering Research Center, Nanjing Agricultural University, Nanjing, Jiangsu, People's Republic of China.

ABSTRACT
Gossypium herbaceum, a cultivated diploid cotton species (2n = 2x = 26, A1A1), has favorable traits such as excellent drought tolerance and resistance to sucking insects and leaf curl virus. G. australe, a wild diploid cotton species (2n = 2x = 26, G2G2), possesses numerous economically valuable characteristics such as delayed pigment gland morphogenesis (which is conducive to the production of seeds with very low levels of gossypol as a potential food source for humans and animals) and resistance to insects, wilt diseases and abiotic stress. Creating synthetic allotetraploid cotton from these two species would lay the foundation for simultaneously transferring favorable genes into cultivated tetraploid cotton. Here, we crossed G. herbaceum (as the maternal parent) with G. australe to produce an F1 interspecific hybrid and doubled its chromosome complement with colchicine, successfully generating a synthetic tetraploid. The obtained tetraploid was confirmed by morphology, cytology and molecular markers and then self-pollinated. The S1 seedlings derived from this tetraploid gradually became flavescent after emergence of the fifth true leaf, but they were rescued by grafting and produced S2 seeds. The rescued S1 plants were partially fertile due to the existence of univalents at Metaphase I of meiosis, leading to the formation of unbalanced, nonviable gametes lacking complete sets of chromosomes. The S2 plants grew well and no flavescence was observed, implying that interspecific incompatibility, to some extent, had been alleviated in the S2 generation. The synthetic allotetraploid will be quite useful for polyploidy evolutionary studies and as a bridge for transferring favorable genes from these two diploid species into Upland cotton through hybridization.

Show MeSH

Related in: MedlinePlus

Validation of the new synthetic allotetraploid of G. herbaceum × G. australe using a randomly selected set of polymorphic SSR primers.From a to h, polymorphic amplicons of F1, S1, S2 and its parents were detected using SSR primers NAU207, NAU704, NAU905, NAU2325, NAU3995, NAU7751, NAU7699 and NAU6064, respectively. Here, showed eight codominant markers. P1, G. herbaceum; P2, G. australe; F1, G. herbaceum × G. australe; S1, synthetic allotetraploid of G. herbaceum × G. australe; S2, progeny from S1 self-pollination; M, molecular marker sizes (100 bp ladder).
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4400159&req=5

pone.0123209.g007: Validation of the new synthetic allotetraploid of G. herbaceum × G. australe using a randomly selected set of polymorphic SSR primers.From a to h, polymorphic amplicons of F1, S1, S2 and its parents were detected using SSR primers NAU207, NAU704, NAU905, NAU2325, NAU3995, NAU7751, NAU7699 and NAU6064, respectively. Here, showed eight codominant markers. P1, G. herbaceum; P2, G. australe; F1, G. herbaceum × G. australe; S1, synthetic allotetraploid of G. herbaceum × G. australe; S2, progeny from S1 self-pollination; M, molecular marker sizes (100 bp ladder).

Mentions: We used a total of 658 SSR primer pairs/combinations that were randomly selected at genetic intervals of 5–10 cM (genome coverage of ~90%) from the linkage map of the G. hirsutum and G. barbadense genome constructed at our institute [27] to screen polymorphic primers between G. herbaceum and G. australe and to confirm the authenticity of the synthetic allotetraploid. Approximately 70% (459/658) of the SSRs detected polymorphisms between these two species, showing a very high diversity at SSR molecular marker level. Of the 459 pairs of polymorphic primers used to characterize the new synthetic allotetraploid, 212 (46%) showed codominance in the synthetic allotetraploid, whereas 140 (31%) were dominant in G. herbaceum and 107 (23%) were dominant to G. australe. The amplicons generated using codominant/ dominant primers in the synthetic allotetraploid demonstrated that it had DNA bands from both/paternal parent(s), further confirming that the synthetic allotetraploid was derived from G. herbaceum and G. australe (Fig 7).


A new synthetic allotetraploid (A1A1G2G2) between Gossypium herbaceum and G. australe: bridging for simultaneously transferring favorable genes from these two diploid species into upland cotton.

Liu Q, Chen Y, Chen Y, Wang Y, Chen J, Zhang T, Zhou B - PLoS ONE (2015)

Validation of the new synthetic allotetraploid of G. herbaceum × G. australe using a randomly selected set of polymorphic SSR primers.From a to h, polymorphic amplicons of F1, S1, S2 and its parents were detected using SSR primers NAU207, NAU704, NAU905, NAU2325, NAU3995, NAU7751, NAU7699 and NAU6064, respectively. Here, showed eight codominant markers. P1, G. herbaceum; P2, G. australe; F1, G. herbaceum × G. australe; S1, synthetic allotetraploid of G. herbaceum × G. australe; S2, progeny from S1 self-pollination; M, molecular marker sizes (100 bp ladder).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4400159&req=5

pone.0123209.g007: Validation of the new synthetic allotetraploid of G. herbaceum × G. australe using a randomly selected set of polymorphic SSR primers.From a to h, polymorphic amplicons of F1, S1, S2 and its parents were detected using SSR primers NAU207, NAU704, NAU905, NAU2325, NAU3995, NAU7751, NAU7699 and NAU6064, respectively. Here, showed eight codominant markers. P1, G. herbaceum; P2, G. australe; F1, G. herbaceum × G. australe; S1, synthetic allotetraploid of G. herbaceum × G. australe; S2, progeny from S1 self-pollination; M, molecular marker sizes (100 bp ladder).
Mentions: We used a total of 658 SSR primer pairs/combinations that were randomly selected at genetic intervals of 5–10 cM (genome coverage of ~90%) from the linkage map of the G. hirsutum and G. barbadense genome constructed at our institute [27] to screen polymorphic primers between G. herbaceum and G. australe and to confirm the authenticity of the synthetic allotetraploid. Approximately 70% (459/658) of the SSRs detected polymorphisms between these two species, showing a very high diversity at SSR molecular marker level. Of the 459 pairs of polymorphic primers used to characterize the new synthetic allotetraploid, 212 (46%) showed codominance in the synthetic allotetraploid, whereas 140 (31%) were dominant in G. herbaceum and 107 (23%) were dominant to G. australe. The amplicons generated using codominant/ dominant primers in the synthetic allotetraploid demonstrated that it had DNA bands from both/paternal parent(s), further confirming that the synthetic allotetraploid was derived from G. herbaceum and G. australe (Fig 7).

Bottom Line: Creating synthetic allotetraploid cotton from these two species would lay the foundation for simultaneously transferring favorable genes into cultivated tetraploid cotton.Here, we crossed G. herbaceum (as the maternal parent) with G. australe to produce an F1 interspecific hybrid and doubled its chromosome complement with colchicine, successfully generating a synthetic tetraploid.The synthetic allotetraploid will be quite useful for polyploidy evolutionary studies and as a bridge for transferring favorable genes from these two diploid species into Upland cotton through hybridization.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Crop Genetics & Germplasm Enhancement, MOE Hybrid Cotton R&D Engineering Research Center, Nanjing Agricultural University, Nanjing, Jiangsu, People's Republic of China.

ABSTRACT
Gossypium herbaceum, a cultivated diploid cotton species (2n = 2x = 26, A1A1), has favorable traits such as excellent drought tolerance and resistance to sucking insects and leaf curl virus. G. australe, a wild diploid cotton species (2n = 2x = 26, G2G2), possesses numerous economically valuable characteristics such as delayed pigment gland morphogenesis (which is conducive to the production of seeds with very low levels of gossypol as a potential food source for humans and animals) and resistance to insects, wilt diseases and abiotic stress. Creating synthetic allotetraploid cotton from these two species would lay the foundation for simultaneously transferring favorable genes into cultivated tetraploid cotton. Here, we crossed G. herbaceum (as the maternal parent) with G. australe to produce an F1 interspecific hybrid and doubled its chromosome complement with colchicine, successfully generating a synthetic tetraploid. The obtained tetraploid was confirmed by morphology, cytology and molecular markers and then self-pollinated. The S1 seedlings derived from this tetraploid gradually became flavescent after emergence of the fifth true leaf, but they were rescued by grafting and produced S2 seeds. The rescued S1 plants were partially fertile due to the existence of univalents at Metaphase I of meiosis, leading to the formation of unbalanced, nonviable gametes lacking complete sets of chromosomes. The S2 plants grew well and no flavescence was observed, implying that interspecific incompatibility, to some extent, had been alleviated in the S2 generation. The synthetic allotetraploid will be quite useful for polyploidy evolutionary studies and as a bridge for transferring favorable genes from these two diploid species into Upland cotton through hybridization.

Show MeSH
Related in: MedlinePlus