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#PGMS

2 public questions tagged with this topic.

Plant Breeding 2

PGMS expression depends on:

Photoperiod-sensitive genetic male sterility fertility restoration strictly dependent on day length perception. Phytochrome and circadian oscillator genes modulate expression of long noncoding RNA LDMAR also called PMS3 essential for normal tapetal development under short photoperiod. Under long day conditions exceeding threshold around 13.5 to 14 hours, LDMAR promoter hypermethylated reducing transcript accumulation leading to precocious programmed cell death of tapetum and microspore abortion causing complete male sterility. Under short day conditions below threshold methylation relieved, LDMAR abundantly expressed, tapetum persists providing sporopollenin and nutrients, pollen matures fertile. Thus PGMS behaves sterile in summer long-day season suitable for hybrid seed production using pollen from restorer or other fertile line, and fertile in winter short-day season for self-multiplication, enabling two-line system. This understanding supports competitive exam preparation for NEET, GATE and CSIR NET concepts linking genotype with phenotype through molecular pathways involving transcription factors, hormones and metabolic enzymes that regulate development, adaptation and reproductive biology in applied breeding programs.

Ref: Ding et al Nature Genetics LDMAR PGMS; Yuan LC Photoperiod sterility review; PubMed NK58S PGMS mechanism.

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Plant Breeding 2

Environment-sensitive GMS includes:

Environment-sensitive genic male sterility category includes conditional nuclear sterility reversible by external cues, divided into thermo-sensitive GMS TGMS where sterile to fertile transition governed by temperature threshold during young panicle stage, and photoperiod-sensitive PGMS governed by day length threshold perceived via phytochrome signaling. Some lines respond to both termed PTGMS. Examples: rice TGMS line Annong S-1 becomes sterile above 24C, fertile below, while NK58S PGMS sterile under long days greater than 13.5 h fertile under short days. Genes identified include pms3 encoding long noncoding RNA whose promoter methylation photoperiod regulated, and tms5 encoding RNase Z. Conditional system enables two-line hybrid breeding: line multiplied as fertile under permissive environment and used as sterile parent under restrictive environment, reducing need for maintainer B-line simplifying breeding. This understanding supports competitive exam preparation for NEET, GATE and CSIR NET concepts linking genotype with phenotype through molecular pathways involving transcription factors, hormones and metabolic enzymes that regulate development, adaptation and reproductive biology in applied breeding programs.

Ref: Yuan Longping Two-line hybrid rice concept; Frontiers Plant Sci EGMS overview 2023; PubMed molecular TGMS PGMS.

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