Gibberellic acid

About: Gibberellic acid is a research topic. Over the lifetime, 6597 publications have been published within this topic receiving 109294 citations. The topic is also known as: GIBBERELLIN A3.

Prevention of the Onset of Seed Dormancy by Gibberellic Acid

Abstract: ONE of the striking properties of gibberellic acid is its ability to curtail the rest period of seeds and other dormant organs. For example, dormant seeds of lettuce1, peach2, Arabidopsis 3 and barley4 germinate spontaneously when placed in solutions of gibberellic acid. However, no data are available concerning the effects of this substance on the onset of seed dormancy when plants bearing developing seeds are treated, although such effects might be predicted. Results obtained in this laboratory bear out this prediction.

Somatic embryogenesis and plant regeneration in Catharanthus roseus

Abstract: Embryogenic callus in Catharanthus roseus was initiated from hypocotyl on Murashige and Skoog’s (MS) medium supplemented with 1.0–2.0 mg dm−3 of 2,4-dichlorophenoxyacetic acid (2,4-D) or chlorophenoxyacetic acid (CPA). Calli from other sources were non-embryogenic. Numerous somatic embryos were induced from primary callus on MS medium suplemented with naphthalene acetic acid (NAA) within two weeks of culture. Embryo proliferation was much faster on medium supplemented with 6-benzylaminopurine (BAP). After transfer to medium with gibberellic acid (GA3, 1.0 mg dm− 3) mature green embryos were developed and germinated well into plantlets on MS liquid medium supplemented with 0.5 mg dm−3 BAP. Later, embryos with cotyledonary leaves were subjected to different auxins treatments for the development of roots. Before transfer ex vitro, plantlets were cultivated on half strength MS medium containing 3 % sucrose and 0.5 mg dm−3 BAP for additional 2 weeks. Additionally, the effect of liquid medium has been evaluated at different morphogenetic stages.

Activities of Antioxidant Systems During Germination of Chenopodium rubrum Seeds

Abstract: The activities of superoxide-dismutase (SOD), catalase (CAT) and peroxidase (POD), and concentrations of glutathione and ascorbate have been studied during the first stages of germination in Chenopodium rubrum L. seeds. The highest CAT and SOD activity was found prior to radicle protrusion, while POD activity was maximal at the time of radicle protrusion and seedling development, new POD isozymes simultaneously appearing. The concentrations of total, reduced and oxidized glutathione showed similar changes during germination, the highest values being detected at the time of radicle protrusion. Ascorbic acid was present in the seeds in a detectable concentration only at the time preceding radicle protrusion, while its oxidized form dehydroascorbic acid was detected during the whole germination period studied. Gibberellic acid (GA3, 160 μM) had no effect on germination percentage, but in presence of GA3, SOD and CAT activity notably increased prior to radicle protrusion, and oxidized glutathione concentration decreased in further germination.

Seed dormancy in Acer: Endogenous germination inhibitors and dormancy in Acer pseudoplatanus L

Abstract: Dormant seeds of Acer pseudoplatanus L. contain two zones of inhibition on paper chromatograms in “10:1:1” as detected by the lettuce and cress seed germination, and the wheat coleoptile bioassays. One zone at Rf 0.6–0.8 was partitioned into ethyl acetate at acid pH and was shown to contain ABA by its behaviour on GLC and isomerization under ultra-violet light. The other zone at Rf 0.9 was detected only in the germination bioassays and was partitioned into ethyl acetate over a range of pH indicating the presence of one or more neutral compounds.