MhNCED3 in Malus hupehensis Rehd. induces NO generation under osmotic stress by regulating ABA accumulation.

Abscisic acid (ABA) biosynthesis has been widely characterized in plants, whereas the effects of ABA biosynthesis on nitric oxide (NO) generation in osmotic stress are less well understood. In this study, Malus hupehensis Rehd. 9-cis-epoxycarotenoid dioxygenase gene (MhNCED3) which is the key gene in ABA biosynthesis was transformed into wild type (WT) and 129B08/nced3 mutant (AtNCED3 deficient), respectively, and two transgenic Arabidopsis lines were obtained.

MhNCED3, a gene encoding 9-cis-epoxycarotenoid dioxygenase in Malus hupehensis Rehd., enhances plant tolerance to Cl- stress by reducing Cl- accumulation.

High Cl(-) concentrations in tissues can be toxic to crop plants and may lead to reduced growth rates and yields. 9-cis-epoxycarotenoid dioxygenase (NCED) is thought to be involved in the biosynthesis of abscisic acid (ABA), which is an important regulator of plant adaptive responses to stress. Here, the expression of MhNCED3 in Malus hupehensis Rehd.

[Effects of cadmium stress on fatty acid composition and lipid peroxidation of Malus hupehensis].

This paper studied the fatty acid composition, reactive oxygen species (ROS), lipoxygenase (LOX) activity, and malondialdehyde (MDA) content in the leaves and roots of Malus hupehensis seedlings under effects of cadmium (Cd) stress. Noticeable changes were observed in the kinds and relative contents of fatty acids after treated with CdCl2 for 7-12 hours. The relative contents of unsaturated fatty acids in leaves and roots reached the maximum after treated for 7 hours, being 82.

[Effects of CdCl2 on grape root mitochondrial characteristics and root activity].

Taking the one-year cutting-seedlings of four grape cultivars (Kyoho, Muscat Hamburg, Long Yan, and Ze Xiang) as test materials, their root mitochondrial hydrogen peroxide (H2O2) content, membrane permeability transition pore (MPTP), membrane potential (Deltapsi), cytochrome C (Cyt c) content, and root activity were measured under effects of CdCl2. For all test grape cultivars, the root mitochondrial H2O2 content and MPTP increased, but the Deltapsi, Cyt c content, and root activity decreased after treated with 0.5 mmol CdCl2 x L(-1).