Target of rapamycin coordinates auxin are involved in exogenous melatonin regulated low temperature tolerance in cucumber seedlings.

Low temperature (LT) is an important environmental factor affecting the growth and yield of plants. Melatonin (MT) can effectively enhance the LT tolerance of cucumber. This study found that LT stress induced the expression of Comt1 (caffeic acid O-methyltransferase 1), with the highest expression being about 2-times that of the control.

Melatonin-mediated low-temperature tolerance of cucumber seedlings requires Ca/CPKs signaling pathway.

Melatonin (Mel) is recognized as a prominent plant growth regulator. This study investigated the alleviating effect of Mel pretreatment on growth inhibition caused by low-temperature (LT) stress (10 °C/6 °C) in cucumber seedlings and explored the role of the Ca/Calcium-dependent protein kinases (CPKs) signaling pathway in Mel-regulated LT tolerance. The main results are as follows: compared to LT treatment alone, 100 μM Mel increased both the content of Ca (highest about 42.

Identification and expression analysis of MAPK cascade gene family in foxtail millet ().

The mitogen-activated protein kinase (MAPK) cascade pathway is a highly conserved plant cell signaling pathway that plays an important role in plant growth and development and stress response. Currently, MAPK cascade genes have been identified and reported in a variety of plants including , , and , but have not been identified in foxtail millet (). In this study, a total of 93 MAPK cascade genes, including 15 , 10 and 68 genes, were identified by genome-wide analysis of foxtail millet, and these genes were distributed on nine chromosomes of foxtail millet.

Involvement of NO and Ca in the enhancement of cold tolerance induced by melatonin in winter turnip rape (Brassica rapa L.).

As a multifunctional phytohormone, melatonin (Mel) plays pivotal roles in plant responses to multiple stresses. However, its mechanism of action remains elusive. In the present study, we evaluated the role of NO and Ca signaling in Mel enhanced cold tolerance in winter turnip rape.

Exogenous sucrose influences KEA1 and KEA2 to regulate abscisic acid-mediated primary root growth in Arabidopsis.

Arabidopsis K-efflux antiporter (KEA)1 and KEA2 are chloroplast inner envelope membrane K/H antiporters that play an important role in plastid development and seedling growth. However, the function of KEA1 and KEA2 during early seedling development is poorly understood. In this work, we found that in Arabidopsis, KEA1 and KEA2 mediated primary root growth by regulating photosynthesis and the ABA signaling pathway.

GR24-mediated enhancement of salt tolerance and roles of HO and Ca in regulating this enhancement in cucumber.

This study investigated the regulation of the exogenous strigolactone (SL) analog GR24 in enhancing the salt tolerance and the effects of calcium ion (Ca) and hydrogen peroxide (HO) on GR24's regulation effects in cucumber. The seedlings were sprayed with (1) distilled water (CK), (2) NaCl, (3) GR24, then NaCl, (4) GR24, then HO scavenger, then NaCl, and (5) GR24, then Ca blocker, then NaCl. The second true leaf was selected for biochemical assays.

Small signaling molecules in plant response to cold stress.

Cold stress is one of the harsh environmental stresses that adversely affect plant growth and crop yields in the Qinghai-Tibet Plateau. However, plants have evolved mechanisms to overcome the impact of cold stress. Progress has been made in understanding how plants perceive and transduce low-temperature signals to tolerate cold stress.

Hydrogen sulfide and nitric oxide are involved in melatonin-induced salt tolerance in cucumber.

Hydrogen sulfide (HS) is a novel gaseous signaling molecule in response to adversity stress. Melatonin (MT) is a multifunctional molecule that plays an important role in regulating plant stress resistance. However, the interactions between HS and MT are still unknown.

Hydrogen peroxide is involved in strigolactone induced low temperature stress tolerance in rape seedlings (Brassica rapa L.).

Strigolactone (SL) is a plant hormone that can improve plant stress resistance by regulating physiological processes and gene expression. GR24 is a synthetic strigolactone, which can also be used as a plant growth regulator. In this paper, the effects of exogenous GR24 on the growth and development of rape (Brassica rapa L.

Overexpression of Brassica campestris BcICE1 gene increases abiotic stress tolerance in tobacco.

In this study, a cDNA of ICE1 (inducer of CBF expression 1) gene, named BcICE1, was isolated from Brassica campestris 'Longyou 6'. The deduced protein has 499 amino acids containing a typical bHLH domain and is highly identical with AtICE1 (85.9%) from Arabidopsis thaliana.

Novel naïve Bayes classification models for predicting the chemical Ames mutagenicity.

Prediction of drug candidates for mutagenicity is a regulatory requirement since mutagenic compounds could pose a toxic risk to humans. The aim of this investigation was to develop a novel prediction model of mutagenicity by using a naïve Bayes classifier. The established model was validated by the internal 5-fold cross validation and external test sets.

Salinity induced the changes of root growth and antioxidative responses in two wheat cultivars.

This study aimed to investigate the inhibitory mechanism of root growth and to compare antioxidative responses in two wheat cultivars, drought-tolerant Ningchun and drought-sensitive Xihan, exposed to different NaCl concentrations. Ningchun exhibited lower germination rate, seedling growth, and lipid peroxidation than Xihan when exposed to salinity. The loss of cell viability was correlated with the inhibition of root growth induced by NaCl stress.

Expression and signal regulation of the alternative oxidase genes under abiotic stresses.

Plants in their natural environment frequently face various abiotic stresses, such as drought, high salinity, and chilling. Plant mitochondria contain an alternative oxidase (AOX), which is encoded by a small family of nuclear genes. AOX genes have been shown to be highly responsive to abiotic stresses.

Cell death of rice roots under salt stress may be mediated by cyanide-resistant respiration.

Treatment with solutions containing high concentrations of NaCl (200 or 300 mM) induced cell death in rice (Oryza sativa L.) roots, as well as the application of exogenous hydrogen peroxide (H2O2). Moreover, the pretreatment with dimethylthiourea (DMTU), a scavenger of H2O2, partially alleviated the root cell death induced by 200 mM NaCl.

Zinc induced phytotoxicity mechanism involved in root growth of Triticum aestivum L.

This study investigated the inhibition mechanism of root growth in wheat seedlings when exposed to different zinc (Zn) concentrations. All applied Zn concentration did not affect seed germination, but reduced root length; in contrast, only Zn at 3mM inhibited significantly the growth of shoot. The loss of cell viability and the significant increases of lignification as well as the increases of hydrogen peroxide (H(2)O(2)), superoxide radical (O(2)(-)) and malondialdehyde levels were observed in the root tissue exposed to Zn treatment.

Responses of seedling growth and antioxidant activity to excess iron and copper in Triticum aestivum L.

The purpose of this study was to analyze phytotoxicity mechanism involved in root growth and to compare physiological changes in the leaves of wheat seedlings exposed to short term iron (Fe) and copper (Cu) stresses (0, 100, 300 and 500μM). All applied Fe or Cu concentrations reduced root and shoot lengths, but seed germination was inhibited by Cu only at 500μM. Analyses using fluorescent dye 2',7'-dichlorodihydrofluorescein diacetate indicated enhanced H(2)O(2) levels in seedling roots under Fe and Cu treatments.

Protective mechanism of desiccation tolerance in Reaumuria soongorica: leaf abscission and sucrose accumulation in the stem.

Reaumuria soongorica (Pall.) Maxim., a perennial semi-shrub, is widely found in semi-arid areas in northwestern China and can survive severe desiccation of its vegetative organs.

Effect of lanthanum ions (La3+) on ferritin-regulated antioxidant process under PEG stress.

The physiological effects of lanthanum(III) ions on the ferritin-regulated antioxidant process were studied in wheat (Triticum aestivum L.) seedlings under polyethylene glycol (PEG) stress. Treatment with 0.

Molecular cloning and characterization of a novel MAP kinase gene in Chorispora bungeana.

Chorispora bungeana Fisch. and C.A.

Effects of enhanced ultraviolet-B radiation on algae and cyanobacteria.

This article provides an overview of existing literature on the ultraviolet-B (UV-B) radiation effects on algae and cyanobacteria. We report on the effects of UV-B radiation to the growth and development, biomass, sensitivity, photosynthetic pigments, UV-B absorbing compounds, photosynthesis, protein and DNA damage, enzyme activity, nitrogen fixation and assimilation of nitrogen, protective mechanisms of algae and cyanobacteria, the accommodation of algae and cyanobacteria to environmental stress, and the effects to ecology system. Many of the studies show the dramatic effects of UV-B radiation; but typically these studies were conducted under conditions with supplemental UV-B irradiance that was higher than would ever occur outside experimental conditions or natural condition.