Ethylene and expansin biosynthesis related genes polymorphism in local apple (Malus domestica Borkh.) cultivars from VIR Collection of plant genetic resources

At Pushkin and Pavlovsk Laboratories of the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR) a diverse collec tion of local apple cultivars is maintained. Some of the cultivars are widely used in breeding programs for their ecological plasticity, increased adaptation to abiotic stress and disease resistance, still there have been no large-scale studies of these local cultivars for fruit storage ability. Fruit softening during storage is an important problem for apple production. Retention of desirable firmness after prolonged storage is one of the key requirements for new apple cultivars. Expansin and ethy lene biosynthesis related genes are known to be involved in control of fruit softening in apple, and gene specific molecular markers have been reported. In this study the polymorphism and allelic configuration of ethylene and expansin biosynthesis related genes Md-ACS1, Md-ACO1 and Md-Exp7 involved in control of fruit softening in 87 local apple cultivars from VIR Collection of Plant Genetic Resources were analyzed. PCR markers Md-ACS1, Md-ACO1 and SSR-marker Md-Exp7 were used in the study. The allele frequencies in the collection generally coincided with the data from previous studies. Md-ACS1 allele 2 associated with reduced ethylene production was found only in three local cultivars, while all the studied local cultivars were heterozygous for the Md-ACO1 locus, as well as most modern Russian apple cultivars. Half of the studied local cultivars were heterozygous for Md-Exp7 (198 : 202). Thirteen local cultivars with rare Md-Exp7 alleles (206, 210 and 212) were detected. No association was found between the Md-Exp7 genotype and the cultivars’ maturation time. The obtained results can be used for additional evaluation of the cultivars’ potential for breeding.

apple, local cultivars, ethylene production, expansin, fruit softening, marker assisted breeding

1. Bratilova N.P., Moksina N.V., Gerasimova O.A., Chepelev N.L. Stages of picking and storage for different cultivars of apple fruit in the Botanical garden named after V.M. Krutovsky. The Bulletin of KrasGAU. 2015;11:146-150.

2. Costa F., Peace C.P., Stella S., Serra S., Musacchi S., Bazzani M., Sansavini S., Van de Weg W.E. QTL dynamics for fruit firmness and softening around an ethylene-dependent polygalacturonase gene in apple (Malus × domestica Borkh.). J. Expt. Bot. 2010;61(11):30293039. DOI 10.1093/jxb/erq130.

3. Costa F., Stella S., Van de Weg W.E., Guerra W., Cecchinel M., Dallavia J., Koller B., Sansavini S. Role of the genes Md-ACOl and MdACSl in ethylene production and shelf life of apple (Malus domestica Borkh.). Euphytica. 2005;141:181-190. DOI 10.1007/s10681-0056805-4.

4. Costa F., Van de Weg W.E., Stella S., Dondini L., Pratesi D., Musacchi S., Sansavini S. Map position and functional allelic diversity of Md-Exp7, a new putative expansin gene associated with fruit softening in apple (Malus × domestica Borkh.) and pear (Pyrus communis). Tree Genet. Genomes. 2008;4:575-586. DOI 10.1007/s11295-0080133-5.

5. Harada T., Sunako T., Wakasa Y., Soejima J., Satoh T., Niizeki M. An allele of 1-aminocyclopropane-1-carboxylate synthase gene (MdACS1) accounts for the low ethylene production in climacteric fruits of some apple cultivars. Theor. Appl. Genet. 2000;101:742-746. DOI 10.1007/s001220051539.

6. Nybom H., Ahmadi-Afzadi M., Garkava-Gustavsson L., Sehic J., Tahir I. Selection for improved fruit texture and storability in apple. Acta Hort. 2012;934(2):849-854. DOI 10.17660/ActaHortic.2012.934.112.

7. Nybom H., Ahmadi-Afzadi M., Sehic J., Hertog M. DNA marker-assisted evaluation of fruit firmness at harvest and post-harvest fruit softening in a diverse apple germplasm. Tree Genet. Genomes. 2013;9:279-290. DOI 10.1007/s11295-012-0554-z.

8. Nybom H., Sehic J., Garkava-Gustavsson L. Modern apple breeding is associated with a significant change in allelic ratio of the ethylene production gene Md-ACS1. J. Hortic. Sci. Biotechnol. 2008;83:673677. DOI 10.1080/14620316.2008.11512442.

9. Oraguzie N.C., Iwanami H., Soejima J., Harada T., Hall A. Inheritance of Md-ACS1 gene and its relationship to fruit softening in apple (Malus × domestica Borkh.). Theor. Appl. Genet. 2004;108:1526-1533. DOI 10.1007/s00122-003-1574-8.

10. Oraguzie N.C., Volz R.K., Whitworth C.J., Bassett H.C.M., Hall A.J., Gardiner S. Influence of Md-ACS1 allelotype and harvest season within an apple germplasm collection on fruit softening during cold air storage. Postharvest Biol. Technol. 2007;44:212-219. DOI 10.1016/j.postharvbio.2006.12.013.

11. Savel’ev N.I., Shamshin I.N., Kudryavtzev A.M. Apples for the alleles of genes of shelf life and quality of fruits. Reports of the Russian Academy of Agricultural Sciences. 2014a;3:17-20.

12. Savel’ev N.I., Shamshin I.N., Savel’eva N.N., Lyzhin A.S. Polymorphism for the MD-EXP-7 gene for expansin biosynthesis in wild species of the genus Malus Mill. Vavilovskii Zhurnal Genetiki i Selektsii = Vavilov Journal of Genetics and Breeding. 2014b;18(4/1): 713-717.

13. Shamshin I.N., Savelieva N.N. Identifying the gene sources for ethylene biosynthesis (MD-ACS1 and MD-ACO1) in genoplasm of wild apple tree species of the genus Malus (L.) Mill. Herald of the Russian Academy of Agricultural Sciences. 2014;4:35-37.

14. Sunako T., Sakuraba W., Senda M., Akada S., Ishikawa R., Niizeki M., Harada T. An allele of the ripening-specific 1-amino-cyclopropane1-carboxylic acid synthase (ACS1) in apple fruit with a long storage life. Plant Physiol. 1999;119(4):1297-1304. DOI 10.1104/pp.119.4. 1297.

15. Suprun I.I., Tokmakov S.V. Allelic diversity of ethylene biosynthesis related MD-ACS1 and MD-ACO1 genes in Russian apple germplasm. Vavilovskii Zhurnal Genetiki i Selektsii = Vavilov Journal of Genetics and Breeding. 2013;17(23):298-302.

16. Zhu Y., Barritt B.H. Md-ACS1 and Md-ACO1 genotyping of apple (Malus × domestica Borkh.) breeding parents and suitability for marker-assisted selection. Tree Genet. Genomes. 2008;4:555-562. DOI 10.1007/s11295-007-0131-z.