Effects of PEG-6000 as a water stress simulator in three varieties of musaceae cultivated under in vitro conditions

Abstract

The purpose of the research was to determine the answer in vitro of three musacea cultivars, yellow bananas (AAA), majoncho “San Andrés” (ABB) and dwarf banana (AAB), under different doses of PEG-6000 causing the normal or ideal osmotic pressure. Children sword corms from the three cultivars were used.

In the lab, the corms were reduced to 10 centimeters and later were disinfected. In the sterile chamber, they were rinsed with demineralized water. Later, it was proceed to cut the yolk in a transversal and longitudinal form to get the apical meristem. These explants  were inoculated in the middle of the nutritive cultivation MS (Murashige & Skoog, 1962) The PEG doses used during all the phases were 0.0, 5.0, 7.5 and 10%. The incubation photoperiod was 16 light hours and 8 in the dark with 1350 lux of intensity, with a minimum temperature of 24°C and a maximum of 26°C.

In the establishing stage, the survival percentage was evaluated, finding a better adaptation of the treatments without PEG. Two 
multiplication cycles were performed and the outbreak production rates were evaluated, which was smaller in the second cycle. In the development and rooting phase, it was evaluated the number of leaves, height of the plant (cm.), number and length of the 
roots (cm). The number of leaves was relatively stabled in all the treatments and in the cultivars. The plant height was slightly hig
her in majoncho with an average of 5.3 cm. On the other hand, the number of roots was smaller with the 10% dose in the cultivars in all the treatments.