Generation and characterisation of colchicine-induced autotetraploid Lavandula angustifolia

Abstract

Lavandula angustifolia (lavender) is a small woody perennial grown for essential oil, which is steam distilled from flowers. To potentially improve size of flowers and oil yield we produced and characterised autotetraploid plants. L. angustifolia seed germinated in the presence of the mitotic spindle inhibitor colchicine at concentrations of 125 mg l -1 or less resulted in plants carrying sports with larger flowers. Propagation of two sports gave rise to putative polyploid cultivars C3/2 and C6/24. Direct chromosome counts in root tip cells of seedlings from four common cultivars of L. angustifolia and the seed lot from which C3/2 and C6/24 were derived was 50 whereas C3/2 and C6/24 had greater than 90 chromosomes indicating they were autotetraploid. Ploidy level assessed by flow cytometry (FCM) of nuclei showed that 12 cultivars of L. angustifolia had similar nuclear DNA content whereas C3/2 and C6/24 had double the amount of DNA confirming autotetraploidy. The genome size (1C-value) of a diploid L. angustifolia cultivar was estimated by FCM to be 0.90 (±0.07) pg. Morphological characteristics were measured in autotetraploid and control plants. Autotetraploids had thicker peduncles, larger flowers and larger seeds than diploids. Scanning electron microscopy revealed peltate glandular trichomes were larger in the tetraploids relative to diploids. Both tetraploid and diploid cultivars had complex non-glandular trichomes on leaves and sepals and two different types of capitate glandular trichomes were identified on leaves. Autotetraploid lavenders represent useful germplasm both for commercial oil production and future breeding.

Overproduction of valuable methoxylated flavones in induced tetraploid plants of Dracocephalum kotschyi Boiss

“…Similar results were also reported in Lavandula angustifolia (Urwin et al 2007) and Arachis paraguariensis (Aina et al 2012).…”

<i>In Vitro</i> Induction of Polyploidy in <i>Sorghum bicolor</i> L.

“…Stomata changes are considered as a fast index for approximating the rate of polyploidy in some of the plants (Beck et al 2003, Thao et al 2003, Van Duren et al 1996. In addition, determination of chlorophyll content as a tool to detect the ploidy level has been reported in some of the plant species such as Lavandula angustifolia (Urwin et al 2007), Ricinus (Timco et al 1981) and pomegranate (Shao et al 2003). Polyploidization while maintaining proper water balance and higher chlorophyll content increases tolerance to environmental stresses (Liu et al 2011).…”

Induction and identification of Stylosanthes guianensis tetraploids

“…In addition, induced polyploid breeding provides a wider germplasm base for breeding programs (Luckett, 1989;Aranada et al, 1997;Osborn et al, 2003;Shao et al, 2003;Thao et al, 2003;Comai, 2005;Omidbaigi et al, 2010). By preventing microtubule assembly and arresting spindle formation during mitosis, colchicine is conventionally and successfully used to induce chromosome doubling in the development of tetraploids (Takamura and Miyajima, 1996;Pinheiro et al, 2000;Nguyen et al, 2003;Petersen et al, 2003;Shao et al, 2003;Liu et al, 2007;Urwin et al, 2007).…”