Development of photoperiod-sensitive cytoplasmic male sterile (PCMS) wheat lines showing high male sterility under long-day conditions and high seed fertility under short-day conditions

The breeding and large-scale adoption of hybrid seeds is an important achievement in agriculture. Rice hybrid seed production uses cytoplasmic male sterile lines or photoperiod/thermo-sensitive genic male sterile lines (PTGMS) as female parent. Cytoplasmic male sterile lines are propagated via cross-pollination by corresponding maintainer lines, whereas PTGMS lines are propagated via self-pollination under environmental conditions restoring male fertility. Despite huge successes, both systems have their intrinsic drawbacks. Here, we constructed a rice male sterility system using a nuclear gene named Oryza sativa No Pollen 1 (OsNP1). OsNP1 encodes a putative glucose–methanol–choline oxidoreductase regulating tapetum degeneration and pollen exine formation; it is specifically expressed in the tapetum and miscrospores. The osnp1 mutant plant displays normal vegetative growth but complete male sterility insensitive to environmental conditions. OsNP1 was coupled with an α-amylase gene to devitalize transgenic pollen and the red fluorescence protein (DsRed) gene to mark transgenic seed and transformed into the osnp1 mutant. Self-pollination of the transgenic plant carrying a single hemizygous transgene produced nontransgenic male sterile and transgenic fertile seeds in 1:1 ratio that can be sorted out based on the red fluorescence coded by DsRed. Cross-pollination of the fertile transgenic plants to the nontransgenic male sterile plants propagated the male sterile seeds of high purity. The male sterile line was crossed with ∼1,200 individual rice germplasms available. Approximately 85% of the F1s outperformed their parents in per plant yield, and 10% out-yielded the best local cultivars, indicating that the technology is promising in hybrid rice breeding and production.

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Diplotaxis muralis (mur) cytoplasmic male sterility system maintainer occurrence and frequency in summer rape

Canadian Journal of Plant Science ◽

10.4141/p99-145 ◽

2000 ◽

Vol 80 (3) ◽

pp. 587-589 ◽

Cited By ~ 1

Author(s):

Teresio C. Riungu ◽

Peter B. E. McVetty

Keyword(s):

Brassica Napus ◽

Cytoplasmic Male Sterility ◽

Key Words ◽

Male Sterility ◽

Frequency Of Occurrence ◽

Male Sterile ◽

Brassica Napus L ◽

Cytoplasmic Male Sterile

No male sterile plants were found in the F1 progeny from crosses between a Diplotaxis muralis cytoplasmic male sterile (mur CMS) semi-winter habit rape (Brassica napus L.) A-line and 101 genetically diverse summer rape cultivars or strains. The frequency of occurrence of mur CMS system maintainer genotypes in summer rape is very low, possibly zero. Key words: Mur CMS system; Brassica napus L.

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Classification of environmentally induced genetic male sterile lines of rice based on their fertility responses to photoperiod and temperature

The Journal of Agricultural Science ◽

10.1017/s0021859600077935 ◽

1996 ◽

Vol 127 (2) ◽

pp. 161-167 ◽

Cited By ~ 4

Author(s):

S. H. Cheng ◽

H. M. Si ◽

L. S. Zhuo ◽

Z. X. Sun

Keyword(s):

Male Sterility ◽

Interaction Effect ◽

Hybrid Rice ◽

Male Sterile ◽

Line System ◽

Genetic Male Sterility ◽

Different Types ◽

Photoperiod Sensitive ◽

Selection Of

SUMMARYThe use of environmentally induced genetic male sterile (EGMS) rice could alter the development of hybrid rice from a three-line system to a two-line system. It is critical for the utilization of EGMS rice to determine which are the main environmental factors influencing fertility changes. Fertility responses to photoperiod (P) and temperature (T) were studied in 101 EGMS rice lines under nine controlled regimes combining three photoperiods (15·0, 14·0 and 12·5 h)x three temperatures (30·1, 24·1 and 23·1 °C). According to the variance analysis of seed-setting data, 96% of the total EGMS lines studied could be divided into three types as follows: (1) photoperiod-sensitive genetic male sterility (PGMS) characterized statistically by significant (P < 0·05) P and P × T interaction effects but by a non-significant T effect on fertility, (2) thermosensitive genetic male sterility (TGMS) by a significant T effect, a non-significant P effect and by either a significant or a non-significant P × T interaction effect on fertility, and (3) photo-thermosensitive genetic male sterility (P-TGMS) by only a significant P × T interaction effect on fertility. Among the japonica EGMS lines studied, PGMS, TGMS and P-TGMS accounted for 32·3, 9·7 and 51·6%, respectively. However, among the indica EGMS lines, no PGMS lines were detected and most of them were TGMS or P-TGMS (61·4 and 35·7%, respectively). The results indicate that the selection of indica PGMS lines of rice might be very difficult. The availability of different types of EGMS rice in two-line system hybrid rice is evaluated and the selection of an ideal model of response to photoperiod and temperature for indica EGMS is discussed.

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High-frequency embryogenesis in male sterile plants of Brassica napus through microspore culture

Canadian Journal of Botany ◽

10.1139/b88-229 ◽

1988 ◽

Vol 66 (8) ◽

pp. 1676-1680 ◽

Cited By ~ 15

Author(s):

Phan V. Chuong ◽

K. P. Pauls ◽

W. D. Beversdorf

Keyword(s):

Brassica Napus ◽

Male Sterility ◽

Constant Temperature ◽

Oilseed Rape ◽

High Frequency ◽

Microspore Culture ◽

Doubled Haploids ◽

Nuclear Genome ◽

Male Sterile ◽

Cytoplasmic Male Sterile

Microspores from several Polima cytoplasmic male sterile (Pol-CMS) and Diplotaxis muralis male sterile (Mur-MS) oilseed rape lines were cultured in a modified Nitsch and Nitsch medium in the dark for 4 weeks. High androgenic frequencies were observed in microspore cultures initiated from plants of both male sterile (MS) types. In cultures maintained at a constant temperature (30 °C) 1 or 2% of the microspores from Pol-CMS or Mur-MS lines, respectively, developed into embryos. A greater percentage of the embryos obtained from the Pol-CMS lines were of good quality than those obtained from the Mur-MS lines (25 vs. 5%). Twenty percent of the plants regenerated from embryos of both lines were spontaneous doubled haploids. The results suggest that no unfavorable cytoplasmic–nuclear genome interaction affecting androgenic potential exists in plants exhibiting Polima or Diplotaxis muralis male sterility.

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