Мutants of inflorescence development in alfalfa (Medicago sativa L.)

• Published in: Vavilovskiĭ zhurnal genetiki i selekt͡s︡ii Vol. 23; no. 6; pp. 700 - 707
• Main Authors: Dzyubenko, N. I., Dzyubenko, E. A.
• Format: Journal Article
• Language: English
• Published: Siberian Branch of the Russian Academy of Sciences, Federal Research Center Institute of Cytology and Genetics, The Vavilov Society of Geneticists and Breeders 10.10.2019
• Subjects: alfalfa; inflorescences; medicago sativa l; mutants; plant development
• ISSN: 2500-0462; 2500-3259
• DOI: 10.18699/VJ19.543

Alfalfa (Medicago sativa L., Medicago varia Mart., Medicago falcata L.) is a perennial leguminous plant  well-known as the queen of forages  cultivated  all over the world. The general  biology and morphology of the plant  has been described in detail. The typical inflorescence of the plant is raceme. Due to the multistep inbreeding process  in this cross-pollinated species, different mutant forms have been  found  in inbred  progenies. They include long racemes, panicle-like racemes  (with fertile and sterile flowers), complicated branched racemes,  and fasciated  inflorescences. The fasciation trait was discovered first in long racemes  and then it was introduced into every mutant inflorescence type by hand  pollination. By means  of pair hybridization,  transitional  forms of some mutants were isolated and the new mutant forms combined two or three  mutant genes.  New gene  names  are proposed for new duplex  and triplex mutant types: lpfas, pi1lpfas, brilpfas. Medicago truncatula is a conventional model species for legume  genome research. M. truncatula and alfalfa share highly conserved nucleotide sequences and exhibit nearly perfect  synteny between the two genomes. The knowledge about inflorescence development in model M. truncatula plants adds to understanding the genetic nature of mutant inflorescence development in alfalfa; therefore, we compiled the information on the genetic regulation of inflorescence development in M. truncatula. The M. truncatula mutant mtpim has a complicated inflorescence structure resembling panicle-like inflorescence in alfalfa. Presently, it is known that the inflorescence architecture in M. truncatula is controlled by spatiotemporal expression  of MtTFL1, MtFULc, MtAP1, and SGL1 through reciprocal repression.  Some mutants isolated in M. truncatula resemble alfalfa mutants in phenotype. The mutant generated by retrotransposon insertion mutagenesis and named sgl1-1 has a cauliflower-like phenotype looking just like the cauliflower mutant in alfalfa. New data concerning genes regulating inflorescence development in model legumes approach us to understanding the phenomenon of inflorescence mutations in alfalfa. The information of inflorescence mutants in nonmodel crops may augment our knowledge of plant development and help crop improvement.