Gibberellin Synthesis Inhibitor Effects on Trees - …

We analyzed P. falciparum treated with INA and AMO-1618 by GC-MS in order to identify sterols or isoprenoids in malaria parasites, but we could not detect any isoprenoids, besides cholesterol (). We might be able to hypothesize that responsible components could be too low or structurally unknown to detect by GC-MS in parasite cells. Data about syntheses of isoprenoids in protozoa, especially in Apicomplexa, remains nil. Intraerythrocytic parasites are known to intake large amounts of erythrocyte contents with surrounding membranes that are cholesterol rich, however, cholesterol is greatly depleted in parasite membranes () . How parasites transport and dispose of excess cholesterol within the cells remain a puzzle. Additionally, does lack of isoprenoids make membranes leaky even in intracellular parasites? A previous study has demonstrated by differential scanning calorimetry and electron spin resonance the association of gibberellin molecules with phospholipid membranes thereby altering the fluidity or viscosity of the lipid bilayer . Clearly, further studies on gibberellin biosynthetic inhibitors could shed light if these compounds could perturb lipid bilayers or alter properties of the membrane phospholipid.

Inhibitors of Gibberellin Biosynthesis: Applications in ..

The method of claim 2 wherein the gibberellin synthesis inhibitor is a pyrimidine.
Photo provided by
Flickr

New gibberellin biosynthesis inhibitors, ..



A second embodiment herein is directed to a method of postponing the germinability of plant seeds for which gibberellin synthesis is necessary for germination and comprises inducing releasable dormancy in non-dormant plant seeds for whichgibberellin synthesis is necessary for germination by the method of the aforestated first embodiment and after a desired interval, for example 1 day to 6 months, releasing the induced dormancy.

Gibberellin Synthesis Inhibitors | Duchefa Biochemie



The seeds that are subject to treatment in the invention herein are those for which gibberellin synthesis is necessary for germination and are for plants which are cultivated, e.g., seeds for vegetables such as lettuce, tomato, pepper, carrot,onion, celery, parsnip, endive, chicory, radish, leek, eggplant, potato and sweet potato; fruits such as Virginia strawberry (Fragaria virginiana); grasses such as Kentucky blue grass (Poa pratensis); trees and shrubs such as pine (Pinus sylvestris) andmullein (Verbascum thapsus); flowers such as impatients (Impatients), primrose (Primula spp.) and evening primrose (Oenothera spp.); and other crops, such as tobacco (Nicotiana tabaccum).

and a time of soaking in solution of gibberellin synthesis inhibitor of at least about 24 hours.
Photo provided by
Flickr

at the symposium Gibberellin and Sterol Synthesis Inhibitors on 5 ..

The method of claim 22 wherein the plant seeds are lettuce seeds.

TECHNICAL FIELD

This invention is directed to inducing releasable dormancy in non-dormant plant seeds for which gibberellin synthesis is necessary for germination.

New Biosynthetically Patterned Inhibitors of Gibberellin ..

The theory that bioactive gibberellins (GAs) act as inhibitors of inhibitors of plant growth was based originally on the slender pea (Pisum sativum) mutant (genotype la cry-s), but the molecular nature of this mutant has remained obscure. Here we show that the genes LA and CRY encode DELLA proteins, previously characterized in other species (Arabidopsis [Arabidopsis thaliana] and several grasses) as repressors of growth, which are destabilized by GAs. Mutations la and cry-s encode nonfunctional proteins, accounting for the fact that la cry-s plants are extremely elongated, or slender. We use the la and cry-s mutations to show that in roots, DELLA proteins effectively promote the expression of GA synthesis genes, as well as inhibit elongation. We show also that one of the DELLA- regulated genes is a second member of the pea GA 3-oxidase family, and that this gene appears to play a major role in pea roots

CAS number 76738-62-0 Molecular weight C 15 H 20 ClN 3 O = 293.8

At 2 µM, INA-induced morphological changes were microscopically visible at 24 h in asynchronous parasite cultures. In order to determine if INA and AMO-1618 targets a specific stage during intraerythrocytic development, we increased concentrations of INA to 50 µM and AMO-1618 to 250 µM. Both inhibitors at these concentrations provoked morphological changes more rapidly than concentrations at their ED50s (). The use of increased concentrations of inhibitors also allowed us to measure the intrinsic sensitivity of the parasites in vitro, and provided clues to the maximal response that can be produced by these inhibitors, as well as their toxicity to the human erythrocytes. Even after 24 h incubation, use of 0.1% DMSO alone gave no effects on growth and morphology of malaria parasites. Parasite swelling and rupture was also observed on P. falciparum cultures treated with other gibberellin biosynthetic inhibitors, such as paclobutrazol and uniconazole P (). These inhibitors, as well as INA, are known to block cytochrome P450-dependent monooxygenases (CYP701A) in plants . Interestingly, the time and the concentrations necessary to provoke morphological changes were different among these compounds, presumably due to differences in solubility and lipophilicity.