Molecular Identification of Malus hupehensis (Tea Crabapple) Accessions Using Simple Sequence Repeats

Abstract

<jats:p>The U.S. National Plant Germplasm System (NPGS) currently holds 36 separate accessions of the `Yichang' clone of <jats:italic>Malus hupehensis</jats:italic> (Pamp.) Rehd. The `Yichang' clone originally entered the United States in 1908 as seed collected for the Arnold Arboretum by E.H. Wilson near Yichang, Hubei Province, China. The original description of <jats:italic>M. hupehensis</jats:italic> omits fruit characters, and botanists frequently augment these omissions with descriptions of the `Yichang' clone. Apomixis occurs in <jats:italic>Malus</jats:italic>, including <jats:italic>M. hupehensis</jats:italic>, and is strongly associated with elevated ploidy levels. Simple sequence repeats (SSRs) were used to characterize 65 accessions of <jats:italic>M. hupehensis</jats:italic>. To check for polyploidy, a set of <jats:italic>M. hupehensis</jats:italic> accessions was evaluated with flow cytometry. The simple sequence repeat phenotypes and ploidy information revealed the `Yichang' clone under various accession names in arboreta. It was neither known nor suspected that the U.S. National Plant Germplasm System held many duplicate accessions of the `Yichang' clone prior to their molecular characterization. Germplasm conservation decisions for <jats:italic>Malus</jats:italic> species can benefit from an increased knowledge of the genetic variation or lack thereof in naturalized populations and ex situ collections.</jats:p>

Molecular Characterization of Kiwifruit (Actinidia) Cultivars and Selections Using SSR Markers

“…This result is also well refl ected by low individual allelic frequencies, because 71.8% of the alleles had allelic frequency <0.05 ( Table 2). The value of mean number of 23.7 alleles per locus observed in this study is high in comparison to the reported values of SSR studies conducted in other plant species with similar ecological and life-history characteristics of wide geographic range, outcrossing and long-lived woody perennials, such as olive (Olea europaea L.), 3.0 alleles per locus (Cipriani et al, 2002); Citrus, 5.5 (Kijas et al, 1995); tea crabapple, 9.4 (Benson et al, 2001); blueberry (Vaccinium corymbosum L.), 7.9 (Levi and Rowland, 1997); avocado (Persea americana M.), 9.5 (Lavi et al, 1994); Pyrus, 11.0 (Yamamoto et al, 2001); apple (Malus domestica Borkh), 12.1 (Hokanson et al, 1998); cherry (Prunus L. sp.…”

“…The UDK96-026 and UDK 96-414 are the most hypervariable loci, with 38 and 32 alleles detected, respectively. This suggests a possibility that somaclonal variability occurs and agrees with crabapple, 0.76 (Benson et al, 2001); and cherry, 0.81 (Cantini et al, 2001). The high ploidy level of A. deliciosa (hexaploid), different ploidy races (diploid and tetraploid) of A. chinensis, and ploidy origins (allohexaploid in A. deliciosa and autotetraploid in A. chinensis) (Huang et al, 1997;Testolin and Ferguson, 1997) might explain the high genetic variation of SSRs in kiwifruit.…”

“…Simple sequence repeats (SSRs) have recently been used successfully as genetic markers for identifying cultivars and germplasm accessions due to their co-dominant inheritance and hypervariability in fruit, such as grape (Vitis sp.) (Botta et al, 1995;Lamboy and Alpha, 1998), tea crabapples (Malus hupehen- (Benson et al, 2001;Hokanson et al, 1998), Citrus (Gulsen and Roose, 2001), and sour cherry (Prunus cerasus L.) (Cantini et al, 2001). More than 40 SSRs from kiwifruit have been developed and about 20 SSRs were verifi ed as single Mendelian loci in intra-and interspecifi c crossed families (Huang et al, 1998;Weising et al, 1996).…”

Chloroplast heterogeneity and historical admixture within the genus Malus

“…The presence of polyploid species suggests that hybridization may be widespread within the Chinese Malus center of origin. One species, M. hupehensis, is apomictic (Benson et al, 2001). Another species, M. xiaojinensis M. H. Cheng & N. G. Jiang (not included in this work) is reported to be a tetraploid facultative apomict (Wang et al, 2012).…”

Effects of Bacillus velezensis FKM10 for Promoting the Growth of Malus hupehensis Rehd. and Inhibiting Fusarium verticillioides

“…Malus hupehensis Rehd. is a valuable and scarce rootstock resource for apple trees in China (Benson et al, 2001;Lin and Sun, 2017). Moreover, the roots of M. hupehensis Rehd.…”