The effects of ultra-high diluted gibberellic acid on in vitro lettuce seed germination.
Keywords: high dilution, in vitro models, plant models
AbstractLettuce seeds bioassays have been used in many different tests such as: alellopathyc models; developing of new drugs; ecotoxicity tests. In most cases, lettuce (Lactuca sativa L., Asteraceae) has been used because of its sensitivity, simultaneous and rapid germination, reliability of germination percentage and homogeneity of seeds. The main goal was to evaluate the effects of ultra-high diluted gibberellic acid (GA3) on lettuce seeds germination and seedling growth. Experiment was performed using Petri dishes containing one disk of Whatman nÂº01 paper watered with 1ml of water. In each Petri dish 10 lettuce seeds(Lactuca sativa L.) cv Regina 500 were placed and 2ml of the different treatment solutions were add: GA33Âµmol, GA3 3CH (10-6), GA3 12CH (10-24), water 12CH and water (no dilution and succussion). One milliliter solutions were added every 2 days of experiment. The experiment was repeated twice and each one consisted in 5 Petri dishes per treatment (n=100). All seeds were maintained in germination incubator under controlled temperature (25Â°C) and photoperiod (16L/8D). The tested substances were prepared according to Brazilian Homeopathic Pharmacopoeia (Brazil, 2011). The experiment was blinded all the time. All seeds germinated at same time (2 days) and after 7 days the germination rate was the same in all treatments. Root was affected just by Water 12 CH, in which shown the longest length (4.59 cm) when compared with others treatments. Shoot length was higher where gibberellin was added in concentration upper then Avogradoâ€™s number.