Differential responses of two conifers to in vitro inoculation with Agrobacterium rhizogenes

Abstract

Young seedlings and calli of European iarch {Larix decidua Mill.) but not jack pine (Pinus banksiana Lamb.) were rapidly infected with Agrobacterium rhizogenes (Riker et al.) Conn. Calli were extensively colonized and necrotic within 2 weeks. Seedlings swelled at the wound site, and developed multiple buds, blue-colored needles with dense aggregations of stomates, or adventitious roots. Inoculation of juvenile conifer tissues with selected strains of plasmid donors may offer opportunity to clone engineered superior tree genotypes through in vitro micropropagation.

Effects of antibiotics on the elimination of Agrobacterium tumefaciens from loblolly pine (Pinus taeda) zygotic embryo explants and on transgenic plant regeneration

“…GUS expression was also observed in adventitious buds regenerated from transgenic calli initiated from zygotic embryos. Foreign gene expression in different conifer species and genotypes was observed in spruce and larch (Clapham and Ekberg, 1986;Diner and Karnosky, 1987;Ellis et al, 1989;McAfee et al, 1993).…”

Root induction in pine (Pinus) and larch (Larix) spp. using Agrobacterium rhizogenes

“…De-rooted larch seedlings, co-cultivated with the same two strains, both rooted at 100%, whereas larch controls rooted spontaneously at 82% (Table 1). Diner & Karnosky (1987) observed no 1988). Also, a significantly greater mean total root length (Table 1) per seedling was recorded compared to larch and jack pine controls.…”

Genetic transformation of conifers and its application in forest biotechnology

“…Infectivity is dependent on the physiological state and developmental stage of the tissue inoculated, as well as the temperature, pH, and the presence of acetosyringone (Stachel et al 1985;Sheikholeslam and Weeks 1987;Godwin et al 1991;James et al 1993;Dillen et al 1997); and 4. Infectivity is dependent upon the selection marker genes and selection agents and promoters used (DeCleene and Deley 1976;Diner and Karnosky 1987;Ellis et al 1989;Bergmann and Stomp 1992;Wenck et al 1999). Humara et al (1999) reported the transfer and expression of foreign chimeric genes in cotyledons of Pinus pinea.…”