In:
Frontiers in Plant Science, Frontiers Media SA, Vol. 13 ( 2022-10-11)
Abstract:
Triploid is considered a reproductive barrier and also a bridge in the formation of polyploids. However, few reports are available in Cymbidium . In this study, diploid ‘Xiaofeng’, sexual triploid ‘Yuchan’ and ‘Huanghe’ of Cymbidium were used to evaluate hybridization compatibility of the triploids. Results showed that the sexual triploids were fertile whether they were used as male or female parents. ‘Yuchan’ produced male gametes of 1 x , 1 x ~2 x , 2 x , 2 x ~3 x , and 3 x at frequencies of 8.89%, 77.78%, 6.67%, 3.33%, and 3.33%, respectively; while ‘Huanghe’ produced 3.33% 1 x , 80.00% 1 x ~2 x , 8.89% 2 x , 5.56% 2 x ~3 x , and 2.22% 3 x male gametes. The cross of ‘Xiaofeng’ with ‘Yuchan’ produced progenies with a wide range of ploidy levels, including one diploid, 34 2×~3× aneuploids, 12 triploids, and one tetraploid, indicating that male gametes produced by sexual triploid were fertile and could be transmitted and fused with egg cells. On the other hand, 10 progenies obtained from the cross of ‘Yuchan’ × ‘Xiaofeng’ were all aneuploids. The cross of ‘Yuchan’ with ‘Huanghe’ produced 40 progenies including three 2×~3× aneuploids, nine 3×~4× aneuploids, 21 tetraploids, six 4×~5× aneuploids, and one pentaploid, suggesting that 2 x gametes, instead of the unreduced ones played a more important role in the formation of tetraploids. The survival rates of the hybrids were all above 80.00%, with the tetraploids at 96.67%. Cytological analysis revealed that during meiosis of sexual polyploids, two chromosome sets of the 2 n gamete were inclined to enter into the same daughter cell, resulting in the production of 2 x gametes. Our results indicate that the triploid cymbidiums are not reproductive barrier but serve as a bridge in the formation of polyploid plants.
Type of Medium:
Online Resource
ISSN:
1664-462X
DOI:
10.3389/fpls.2022.1029915
DOI:
10.3389/fpls.2022.1029915.s001
DOI:
10.3389/fpls.2022.1029915.s002
DOI:
10.3389/fpls.2022.1029915.s003
DOI:
10.3389/fpls.2022.1029915.s004
DOI:
10.3389/fpls.2022.1029915.s005
Language:
Unknown
Publisher:
Frontiers Media SA
Publication Date:
2022
detail.hit.zdb_id:
2687947-5
detail.hit.zdb_id:
2613694-6
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