Intersimple Sequence Repeats Distinguish Genetic Differences in Easter Lily ‘Nellie White’ Clonal Ramets within and among Bulb Growers over Years

Abstract

<jats:p>The large genome size of easter lily [<jats:italic>Lilium longiflorum</jats:italic> (77.1 pg/2C nucleus)], coupled with repetitive DNA sequences, makes it difficult to use molecular techniques to identify or fingerprint lily (<jats:italic>Lilium</jats:italic>) species, hybrids, and clones. Previous research demonstrated that amplified fragment length polymorphisms could not be optimized for consistency and repeatability to obtain reliable genetic variation assessments of lily species and clones. The objective of this research was to analyze the effectiveness and stringency of intersimple sequence repeats (ISSRs) to determine genetic differences between <jats:italic>L. longiflorum</jats:italic> ‘Nellie White’ clonal ramet populations from bulb growers over years. DNA from closely related clones of <jats:italic>L. longiflorum</jats:italic> ‘Nellie White’ included 2002 (n = 11 bulb lots) and 2003 (n = 12 bulb lots). Comparison cultivars and species were also included. Five University of British Columbia (UBC) primers (P808, P810, P811, P814, and P818) that were used produced 56 polymorphic loci. ISSR banding patterns were consistent among three replications within ‘Nellie White’ clonal genotypes. ‘Nellie White’ clones differed significantly within (82%) and among (18%) growers in 2002 and 2003. ‘Nellie White’ clones are not uniform or part of a single ramet population. Principal clades within years separated at Nei's genetic distances (GDs) of GD = 0.6 (growers 2, 4, and 12) to GD = 0.82 (grower 6) in 2002 and GD = 0.51 (grower 4) to GD = 0.78 (grower 14). The most closely related ‘Nellie White’ clones within growers ranged from GD = 0.8 to 0.95 in 2002 and GD = 0.7 to 0.91 for 2003. Five top-performing growers (1, and 3–6) from previous morphological studies and, particularly growers 3 and 5, were in similar clades, cosegregating with phenotypic traits of stem emergence and flowering dates. The lack of a meiotic sieve (Muller's ratchet) may be responsible for the high level of mutational differences present in the ‘Nellie White’ clones and significantly affects the ability of commercial greenhouse growers to produce a uniform easter lily crop, particularly in years when the Easter holiday is early.</jats:p>

LTR-retrotransposons and inter-retrotransposon amplified polymorphism (IRAP) analysis in Lilium species

“…The huge genome of lily often posited ambiguity in recording bands from too spurious background bands in AFLP (Fay et al 2005). Anderson et al (2010) reported ISSR (inter simple sequence repeat) polymorphisms to differentiate the Easer lily 'Nellie White' clonal ramets within and among bulb growers over years in North America (Anderson et al 2010). Recently, two reports are available on the simple sequence repeat (SSR) markers.…”

Production of Polyploids and Unreduced Gametes in Lilium auratum × L. henryi Hybrid

“…Currently, the most important groups for commercial breeding comprise of the Trumpet lily group, including L. longiflorum of the section Leucolirion, the Asiatic hybrid group of the section Sinomartagon and the Oriental hybrid group of the section Archelirion 3. All three sections comprise species with distinct, desirable horticultural characteristics.…”

FLOWER INITIATION AND DEVELOPMENT IN ENDEMIC IRANIAN LILY (Lilium ledebourii Boiss.)

“…The successive stages are more or less easy to separate, but the knowledge on the factors that control them and the determination of the period of the growth cycle, during which they happen in the bulb, are necessary [De Hertogh and Le Nard 1993] for the domestication of a plant. Anderson et al [2010] have reported that, in Lilium, flower formation starts during or towards the end of the cold storage period, but it is only completed after planting. Lilium species were divided into four groups depending on their time of flower initiation by Ohkawa [1977].…”