Methods for Selection of Low‐Temperature Tolerant Mutants of Chrysanthemum morifolium Ramat. Using Irradiated Cell Suspension Cultures III. Comparison of Mutants Selected with or without Preselection in vitro at Low‐Temperature

Abstract

One hundred variants ofChrysanthemum. morifoHum cv. 'Parliament', selected on a single plant basis for early flowenng at low temperature, were tested on a clonal basis. These variants originated from irradiated or non-irradiated microcalli subjected to a one-step greenhouse selection procedure, or, a two-step selection procedure (preselection in vitro at 6 °C followed by selection in the greenhouse). Clones originating from irradiated calli flowered significantly earlier than the controls. Most of the low-temperature tolerant (LTT) mutants were found among plants obtained by the one-step selection procedure. Variants originating from slowly regenerating calli yielded more LTT mutants as compared to those of fast(er) regenerating caUi. We therefore conclude that, irradiation and subsequent selection of plants from slowly regenerating calli considerably increases the efficiency of selecting LTT mutants. The expected advantage of a preselection in vitro at low-temperature could not be confirmed.

Methods for Selection of Low‐Temperature Tolerant Mutants of Chrysanthemum morifolium Ramat. Using Irradiated Cell Suspension Cultures II. Preselection in vitro under Low‐Temperature Stress

“…Procedures of suspension culture and mutation induction by X-irradiation in Chrysanthemum cv. 'Parliament' were described by HuiTEMA et al (1989). After irradiation plated cell aggregates (< 2 mm) were cultured at 6 °C and 16 h daily illumination (10;uE m"^ sec'S Philips TLD 25) for 90 days and then transferred to 24 °C temperature conditions.…”

“…The efficiency of both procedures was compared by using in vitro cultures of the same origin in simultaneously running experiments. A previous paper reported on the regeneration of plants from X-irradiated suspension cultures at 24 °C and on screening for early flowering in the greenhouse at suboptimal temperature and light conditions (HUITEMA et al 1989). In the second part of the series of experiments described here, the effect of an in vitro cold treatment on LTT-mutant selection was investigated.…”

In vitro induction of mutation in cotton (Gossypium hirsutum L.) and isolation of mutants with improved yield and fiber characters

“…In the past few years ionizing radiation and chemical mutagens to plant tissue culture and their response on in vitro mutation efficiency has been reported in many major crops such as potato (Al-Safadi et al 2000) and Chrysanthemum (Mandal et al 2000). The importance of in vitro mutagenesis and its vital role in inducing agronomic characters (Chopra 2005), disease resistance (Liu et al 2005), resistance to salinity (Alvarez 2002), NaCl-tolerant mutant in Chrysanthemum (Hossain et al 2006), low-temperature-tolerant mutants (Huitema et al 1991) have been reported. Improvement of crop plants have also been reported in soybean (Hofmann et al 2004), cassava (Joseph et al 2004), potato (Li et al 2005) Chrysanthemum (Datta et al 2005), cotton (Muthusamy and Jayabalan 2007) and groundnut .…”

Phenotypic differences in transgenic plants of chrysanthemum

“…Of course, the infiuence of somaclonal variation on phenotypic differences in plants regenerated in vitro cannot be ignored. Somaclonal variation in chrysanthemum has been described by many authors (Sutter and Langhans 1981, Preil et al 1983, Benetka and Kodytek 1988, Khalid et al 1989, Huitema et al 1989, Malaure et al 1991.…”