Effect of increased sucrose and macroelement levels in the medium by in vitro propagation of spathiphyllum 'Petite'.

摘要

Two kinds of previously established in vitro cultures of Spathiphyllum 'Petite' were used to study the effect of full and double strength MS macroelement levels combined with 20 and 40 g/L sucrose. Along with normal shoot cultures a special growth formation was also evaluated. We called this formation GGb (green globular bud) distinguishing them from GGB (green globular bodies). They consist of green, globular tissue that appear to be growing in colonies. The cultures were maintained for 60 days on the following media: 0.5 mg/L benzyl-adenine combined with 1- or 2-fold MS macroelement levels and 20 or 40 g/L sucrose, (AS1, AS2-20 g/L sucrose+1x/2x MS; AS3, AS4-40 g/L sucrose+1x/2x MS). We measured morphological characteristics, chlorophyll content and dry weight percentages. According to the results the number and length of shoots was significantly lower in the medium AS4 (5.25 pcs, 30.8 mm) than AS1 (10.5 pcs, 40.9 mm), but the dry weight percentage (15.78%) was almost twofold that of AS1 (8.49%). The number of leaves was statistically equal between the treatments, but the leaf form was different: AS3 and AS4 media resulted in more oblong leaves than AS1 or AS2. The chlorophyll content was significantly lower in shoots growing in the medium AS3 (194 micro g/g) than in the others (all above 1000 micro g/g), and the estimated shoot fresh weight was also lower. Examining the GGbs we can state that none of the parameters were significantly different between the treatments. The multiplication rate of GGbs seems to be lower (4x on average) than normal shoots (9, 5x on average) using the evaluated media. They could be a new form for the in vitro propagation of Spathiphyllum taxa because they may be suitable for mass-propagation systems using liquid media.