New techniques for the in vitro culture of Alstroemeria hybrids

Alessandro Chiari, University of Connecticut

Abstract

Butterfly-type and hybrid-type Alstroemeria hybrids were grown on different media at different concentrations of 6-benzylaminopurine (BA) and 1-naphthalene acetic acid (NAA). BA was necessary to induce rhizome branching and concentrations higher than 0.4 $\mu$M BA did not increase branching. Differences in branching ability between hybrid-type and butterfly-type and within the butterfly-type group suggested that branching strongly depends on genotype. NAA was necessary for rooting in vitro and for survival after transplanting into soil. Liquid, shaken cultures of Alstroemeria 'Sweet Laura$\sp\circler$' and 'Redcoat$\sp\circler$' showed that liquid medium did not induce hyperhydricity but increased rhizome branching after 6 and 9 weeks of subculture. Completely submerged and partially submerged liquid static cultures of 'Sweet Laura$\sp\circler$' and 'Redcoat$\sp\circler$' did not induce hyperhydricity although explant survival was only 72.2% and 80.0%, respectively. Survival was higher in 'Sweet Laura$\sp\circler$' than in 'Redcoat$\sp\circler$' and partially submerged explants had 100 and 60% survival, respectively, making partially submerged liquid culture of 'Sweet Laura$\sp\circler$' a valid alternative to semisolid medium. Alstroemeria rhizome tips could be split in 2 halves with a horizontal or a vertical cut and were able to regenerate new rhizomes from their axillary buds. Survival of the splits was 85.9 and 80.7% for 'Sweet Laura$\sp\circler$' and 'A30', respectively. Over a period of 12 weeks, rhizome splitting with vertical cut allowed to increase propagules production of 194% for 'Sweet Laura$\sp\circler$' and 213% for 'A30'. Axillary meristem tips excised from rhizomes were the best initial explants for meristem culture of Alstroemeria. BA was not essential for rhizome formation, although the use of 8.9 $\mu$M BA significantly increased the number of meristems that did develop into a rhizome. Size affected explant survival and the percentage of alstroemeria mosaic potyvirus (AlMV) that was eradicated. Meristem tips (0.7 mm) and buds (2 mm) had 12.2 and 34.7% survival, respectively, while the rate of AlMV elimination was 73.7 and 14.7%, respectively. Virus-free plants produced more floral and vegetative stems, longer floral stems and had higher fresh mass than infected plants.

Recommended Citation

Alessandro Chiari, "New techniques for the in vitro culture of Alstroemeria hybrids" (January 1, 1998). ETD Collection for University of Connecticut. Paper AAI9832002.
http://digitalcommons.uconn.edu/dissertations/AAI9832002