A class II hydrophobin gene , HFB2 - 6 , was cloned from Trichoderma asperellum ACCC30536 and its biocontrol function was studied .

According to our previous transcriptome data , six of the eight class II hydrophobin genes were obviously differential expression in four inducing conditions , especially the gene HFB2 - 6 .

Moreover , HFB2 - 6 proven to be differentially transcribed under eight different treatments .

HFB2 - 6 transcripts were up-regulated under 1 % Alternaria alternata cell wall and 5 % A. alternata fermentation liquid treatments , and by nutritional stress conditions , suggesting that HFB2 - 6 plays roles in interactions with both biotic and abiotic environmental conditions .

HFB2 - 6 expression was down-regulated under 1 % poplar leaf powder culture conditions , but its expression was up-regulated under 1 % poplar root powder , indicating that HFB2 - 6 has a function in root colonization .

Furthermore , the recombinant hydrophobin rHFB2 - 6 was successfully expressed in Escherichia coli BL21-HFB2 - 6 and purified from the recombinant strain .

Genes related to both the jasmonic acid and salicylic acid signal transduction pathways were up-regulated by interaction with renatured rHFB2 - 6 .

The ORCA3 ( octadecanoid-derivative responsive Catharanthus AP2-domain ) gene of the poplar jasmonic acid signal transduction pathway showed a peak expression of 4.48 times at 2 h , and the peak expression of PR1 ( pathogenesis-related protein gene ) in the salicylic acid signal transduction pathway was 4.58 times at 72 h. Two genes , MP ( monopteros ) and GH3.17 ( auxin original response gene ) , in the auxin signal transduction pathway were also up-regulated after induction with rHFB2 - 6 , indicating that rHFB2 - 6 can promote poplar growth and confer broad-spectrum resistance to pathogens .


Many induced responses in plants are systemic .

Therefore , root-induced responses may alter leaf quality for shoot herbivores .

Previously , we found that root and shoot application of jasmonic acid ( JA ) to feral Brassica oleracea both induced glucosinolates in the leaves .

However , the types of glucosinolates that increased in root- and shoot induced plants were different .

Here we analyse whether primary metabolites , such as sugars and amino acids , are also differentially affected .

Moreover , we test whether chemical differences in root- and shoot-induced plants differentially affect growth of the generalist Mamestra brassicae and the specialist Pieris rapae .

Comprehensive analysis of glucosinolates , amino acid and sugars with principal component analysis revealed that leaf chemical profiles were affected both by JA application and by the organ that was induced .

Shoot-induction increased indole glucosinolates , whereas root-induction induced aliphatic glucosinolates in the leaves .

Leaves of shoot-induced plants had lower total sugar and total amino acid levels , whereas in root-induced plants only total sugar levels were significantly decreased .

(Iso)leucine responded significantly different from the general trend , which allowed us to discuss the potential role of Myb transcription factors which are coordinating JA-induced glucosinolate and amino acid responses in Arabidopsis thaliana .

Both M. brassicae and P. rapae grew the slowest on leaves of shoot-induced plants .

M. brassicae growth and survival was also reduced on root-induced plants , whereas P. rapae growth on these plants was similar to that on controls .

Specialist and generalist herbivores thus are differentially affected by the chemical changes after root and shoot-JA application .


Changes in specialized metabolites were analyzed in wheat leaves inoculated with Bipolaris sorokiniana , the causal agent of spot blotch of Poaceae species .

HPLC analysis detected the accumulation of six compounds in B. sorokiniana-infected leaves .

Of these , we purified two compounds by silica gel and ODS column chromatography and preparative HPLC , and identified them as cinnamic acid amides , N-cinnamoyl-9-hydroxy-8-oxotryptamine and N-cinnamoyl-8-oxotryptamine , by spectroscopic analyses .

The remaining four compounds were predicted to be p-coumaric acid amides of hydroxyputrescine , hydroxyagmatine , hydroxydehydroagmatine , and agmatine by mass spectrometry .

The accumulation of two cinnamic acid amides was also induced by Fusarium graminearum infection , and by treatment with CuCl(2 ) , jasmonic acid , and isopentenyladenine .

Antifungal activity of these amides was shown by inhibition of conidial germination and germ tube elongation of F. graminearum and Alternaria brassicicola , indicating that they act as phytoalexins .

The accumulation of these amides also detected in barley leaves treated with CuCl(2 ) .

We examined the accumulation of 25 phenylamides in B. sorokiniana-infected wheat leaves using LC-MS/MS .

Hydroxycinnamic acid amides of tryptamine , serotonin , putrescine , and agmatine , were induced after infection with B. sorokiniana .

Thus , the induced accumulation of two groups of phenylamides , cinnamic acid amides with indole amines , and p-coumaric acid amides with putrescine and agmatine related amines , represents a major metabolic response of wheat to pathogen infection .


The peduncle of water hyacinth ( Eichhornia crassipes ) showed the downward bending within 24 hours after full flowering .

Previously it was suggested that the downward bending of peduncle might be induced by the differential growth of the epidermal cells of the portion because of the differential distribution of auxin in the upper side of the bending part of the peduncle .

In order to investigate the effect of auxin and gravity on the peduncle bending in Water hyacinth , we examined the growth reaction of peduncle and the effects of plant hormones on the bending of peduncle under simulated microgravity , and the sedimentable amyloplast on earth and three dimensional (3D)-clinostat .

As a result it was confirmed that the downward bending of peduncle in water hyacinth is the positive gravitropism , and that its phenomenon is caused by the differential distribution of auxin in the upper side of bending part of peduncle .

It was found that the amyloplast sediments toward gravity direction in the bending part of the peduncle .

From the present results , any direct relation between the sedimentable amyloplast and auxin transport were not cleared in the peduncle of water hyacinth .


Histone acetylation is modulated through the action of histone acetyltransferases and deacetylases , which play key roles in the regulation of eukaryotic gene expression .

Previously , we have identified a yeast histone deacetylase REDUCED POTASSIUM DEPENDENCY3 ( RPD3 ) homolog , HISTONE DEACETYLASE19 ( HDA19 ) ( AtRPD3A ) , in Arabidopsis thaliana .

Here , we report further study of the expression and function of HDA19 .

Analysis of Arabidopsis plants containing the HDA19:beta-glucuronidase fusion gene revealed that HDA19 was expressed throughout the life of the plant and in most plant organs examined .

In addition , the expression of HDA19 was induced by wounding , the pathogen Alternaria brassicicola , and the plant hormones jasmonic acid and ethylene .

Using green fluorescent protein fusion , we demonstrated that HDA19 accumulated in the nuclei of Arabidopsis cells .

Overexpression of HDA19 in 35S : HDA19 plants decreased histone acetylation levels , whereas downregulation of HDA19 in HDA19-RNA interference ( RNAi ) plants increased histone acetylation levels .

In comparison with wild-type plants , 35S : HDA19 transgenic plants had increased expression of ETHYLENE RESPONSE FACTOR1 and were more resistant to the pathogen A. brassicicola .

The expression of jasmonic acid and ethylene regulated PATHOGENESIS-RELATED genes , Basic Chitinase and beta-1,3-Glucanase , was upregulated in 35S : HDA19 plants but downregulated in HDA19-RNAi plants .

Our studies provide evidence that HDA19 may regulate gene expression involved in jasmonic acid and ethylene signaling of pathogen response in Arabidopsis .


Plants are photosynthetic organisms that depend on sunlight for energy .

Plants respond to light through different photoreceptors and show photomorphogenic development .

Apart from Photosynthetically Active Radiation ( PAR ; 400 - 700 nm ) , plants are exposed to UV light , which is comprised of UV-C ( below 280 nm ) , UV-B ( 280 - 320 nm ) and UV-A ( 320 - 390 nm ) .

The atmospheric ozone layer protects UV-C radiation from reaching earth while the UVR8 protein acts as a receptor for UV-B radiation .

Low levels of UV-B exposure initiate signaling through UVR8 and induce secondary metabolite genes involved in protection against UV while higher dosages are very detrimental to plants .

It has also been reported that genes involved in MAPK cascade help the plant in providing tolerance against UV radiation .

The important targets of UV radiation in plant cells are DNA , lipids and proteins and also vital processes such as photosynthesis .

Recent studies showed that , in response to UV radiation , mitochondria and chloroplasts produce a reactive oxygen species ( ROS ) .

Arabidopsis metacaspase-8 ( AtMC8 ) is induced in response to oxidative stress caused by ROS , which acts downstream of the radical induced cell death ( AtRCD1 ) gene making plants vulnerable to cell death .

The studies on salicylic and jasmonic acid signaling mutants revealed that SA and JA regulate the ROS level and antagonize ROS mediated cell death .

Recently , molecular studies have revealed genes involved in response to UV exposure , with respect to programmed cell death ( PCD ) .


Hot peppers are sensitive to low temperature , and seed browning significantly reduces the fruit quality .

This study aims to clarify the mechanisms of seed browning in terms of metabolite changes .

Metabolites were analysed during a 30-day-storage period at 2 ° C and 10 ° C .

Gamma-aminobutyric acid , tyrosine , phenylalanine , and isoleucine concentrations were significantly higher at 2 ° C storage than at 10 ° C .

Reactive oxygen species ( ROS ) generation was associated with seed browning .

Transcription of jasmonic acid synthesis and ROS scavenging genes were higher in hot peppers stored at 2 ° C than those stored at 10 ° C .

This study elucidated the mechanisms underlying seed browning and chill damage in hot peppers during storage at low temperatures and our findings may help improve hot peppers ' quality following harvesting .


BACKGROUND : Sugarcane smut caused by Sporisorium scitamineum is one of the most severe fungal diseases in the sugarcane industry .

Using a molecular biological technique to mine sugarcane resistance genes can provide gene resources for further genetic engineering of sugarcane disease-resistant breeding .

Jasmonate ZIM ( zinc-finger inflorescence meristem ) domain ( JAZ ) proteins , which involved in the responses to plant pathogens and abiotic stresses , are important signaling molecules of the jasmonic acid ( JA ) pathway .

RESULTS : Seven differentially expressed sugarcane JAZ genes , ScJAZ1-ScJAZ7 , were mined from the transcriptome of sugarcane after inoculation with S. scitamineum .

Bioinformatic analyses revealed that these seven ScJAZ genes encoded basic proteins that contain the TIFY and CCT_2 domains .

Quantitative reverse transcription polymerase chain reaction ( qRT-PCR ) analysis demonstrated that the ScJAZ1-ScJAZ7 genes were tissue specific and differentially expressed under adverse stress .

During S. scitamineum infection , the transcripts of ScJAZ4 and ScJAZ5 were both upregulated in the susceptible genotype ROC22 and the resistant genotype Yacheng05 - 179 ; ScJAZ1 , ScJAZ2 , ScJAZ3 , and ScJAZ7 were downregulated in Yacheng05 - 179 and upregulated in ROC22 ; and the expression of ScJAZ6 did not change in ROC22 , but was upregulated in Yacheng05 - 179 .

The transcripts of the seven ScJAZ genes were increased by the stimuli of salicylic acid and abscisic acid , particularly methyl jasmonate .

The expression of the genes ScJAZ1-ScJAZ7 was immediately upregulated by the stressors hydrogen peroxide , sodium chloride , and copper chloride , whereas slightly induced after treatment with calcium chloride and polyethylene glycol .

In addition , the expression of ScJAZ6 , as well as seven tobacco immunity-associated marker genes were upregulated , and antimicrobial activity against Pseudomonas solanacearum and Fusarium solani var . coeruleum was observed during the transient overexpression of ScJAZ6 in Nicotiana benthamiana , suggesting that the ScJAZ6 gene is associated with plant immunity .

CONCLUSIONS : The different expression profiles of the ScJAZ1-ScJAZ7 genes during S. scitamineum infection , the positive response of ScJAZ1-ScJAZ7 to hormones and abiotic treatments , and the function analysis of the ScJAZ6 gene revealed their involvement in the defense against biotic and abiotic stresses .

The findings of the present study facilitate further research on the ScJAZ gene family especially their regulatory mechanism in sugarcane .


The development of flower buds inSoldanella minima grown at 15 ° or above is stopped at the stage of sporogenous cells in the anthers .

2 . Low temperature overcomes this inhibition , resulting in microsporogenesis and subsequent flowering .

Microsporogenesis must thus be considered as a phase initiated only at low temperature .

Photoperiod does not seem to playa decisive role in this process .

3 . Applied gibberellic acid substitutes for the cold requirement of the flower buds .


Below-ground microbes can induce systemic resistance against foliar pests and pathogens on diverse plant hosts .

The prevalence of induced systemic resistance ( ISR ) among plant-microbe-pest systems raises the question of host specificity in microbial induction of ISR .

To test whether ISR is limited by plant host range ( , ) we tested the ISR-inducing ectomycorrhizal fungus Laccaria bicolor on the nonmycorrhizal plant Arabidopsis thaliana .

We used the cabbage looper Trichoplusia ni and bacterial pathogen Pseudomonas syringae pv . tomato DC3000 ( Pto ) as readouts for ISR on Arabidopsis .

We found that root inoculation with L. bicolor triggered ISR against T. ni and induced systemic susceptibility ( ISS ) against the bacterial pathogen Pto .

We found that L. bicolor-triggered ISR against T. ni was dependent on jasmonic acid signaling and salicylic acid biosynthesis and signaling .

Heat-killed L. bicolor and chitin were sufficient to trigger ISR against T. ni and ISS against Pto .

The chitin receptor CERK1 was necessary for L. bicolor-mediated effects on systemic immunity .

Collectively our findings suggest that some ISR responses might not require intimate symbiotic association , but rather might be the result of root perception of conserved microbial signals .


Leaf senescence is a complicated developmental process that involves degenerative changes and nutrient recycling .

The progress of leaf senescence is controlled by various environmental cues and plant hormones , including ethylene , jasmonic acid , salicylic acid , abscisic acid , cytokinins , and strigolactones .

The production of strigolactones is induced in response to nitrogen and phosphorous deficiency .

Strigolactones also accelerate leaf senescence and regulate shoot branching and root architecture .

Leaf senescence is actively promoted in a nutrient-poor soil environment , and nutrients are transported from old leaves to young tissues and seeds .

Strigolactones might act as important signals in response to nutrient levels in the rhizosphere .

In this review , we discuss the possible roles of strigolactones during leaf senescence .


The cytokinin activity has been isolated and identified from extracts of immature mango ( Mangifera indica L. ) seeds .

The structures of zeatin , zeatin riboside , and N(6)-(Delta(2)-isopentenyl)adenine riboside were confirmed on the basis of their chromatographic behavior and mass spectra of trimethylsilyl derivatives .

Both trans and cis isomers of zeatin and zeatin riboside were also identified by the retention times of high performance liquid chromatography .

In addition , an unidentified compound appeared to be a cytokinin glucoside .

The concentration of cytokinins in the panicle and pulp of mango reached a maximum 5 to 10 days after full bloom and decreased rapidly thereafter .

The cytokinin level in the seed remained high until the 28th day after full bloom .

The quantity of cytokinins in pulp per fruit increased from the 10th day after full bloom , the maximum being attained around the 50th day after full bloom .

Similarly , the amount of cytokinins per seed increased from the 10th day after full bloom , reaching a peak on the 40th day and decreasing gradually thereafter .

A high percentage of fruit set in mango was persistently maintained by supplying 6-benzylaminopurine ( 1.5 x 10(3 ) micromolar ) onto the panicle at the anthesis stage and by supplying gibberellic acid ( 7.2 x 10(2 ) micromolar ) and naphthalene acetamide ( 3.1 x 10 micromolar ) at the young fruit stage .


BACKGROUND : Drought is a severe environmental stress .

It is estimated that about 50 % of the world rice production is affected mainly by drought .

Apart from conventional breeding strategies to develop drought-tolerant crops , innovative computational approaches may provide insights into the underlying molecular mechanisms of stress response and identify drought-responsive markers .

Here we propose a network-based computational approach involving a meta-analytic study of seven drought-tolerant rice genotypes under drought stress .

RESULTS : Co-expression networks enable large-scale analysis of gene-pair associations and tightly coupled clusters that may represent coordinated biological processes .

Considering differentially expressed genes in the co-expressed modules and supplementing external information such as resistance/tolerance QTLs , transcription factors , network-based topological measures , we identify and prioritize drought-adaptive co-expressed gene modules and potential candidate genes .

Using the candidate genes that are well-represented across the datasets as ' seed ' genes , two drought-specific protein-protein interaction networks ( PPINs ) are constructed with up- and down-regulated genes .

Cluster analysis of the up-regulated PPIN revealed ABA signalling pathway as a central process in drought response with a probable crosstalk with energy metabolic processes .

Tightly coupled gene clusters representing up-regulation of core cellular respiratory processes and enhanced degradation of branched chain amino acids and cell wall metabolism are identified .

Cluster analysis of down-regulated PPIN provides a snapshot of major processes associated with photosynthesis , growth , development and protein synthesis , most of which are shut down during drought .

Differential regulation of phytohormones , e.g. , jasmonic acid , cell wall metabolism , signalling and posttranslational modifications associated with biotic stress are elucidated .

Functional characterization of topologically important , drought-responsive uncharacterized genes that may play a role in important processes such as ABA signalling , calcium signalling , photosynthesis and cell wall metabolism is discussed .

Further transgenic studies on these genes may help in elucidating their biological role under stress conditions .

CONCLUSION : Currently , a large number of resources for rice functional genomics exist which are mostly underutilized by the scientific community .

In this study , a computational approach integrating information from various resources such as gene co-expression networks , protein-protein interactions and pathway-level information is proposed to provide a systems-level view of complex drought-responsive processes across the drought-tolerant genotypes .


This study was designed to examine the effects of NaCl pretreatment on the seed germination of white clover ( Trifolium repens cv . Ladino ) under water stress induced by 19 % polyethylene glycol ( PEG ) 6000 .

Lower concentrations of NaCl ( 0.5 , 1 , and 2.5 mM ) pretreatment significantly alleviated stress-induced decreases in germination percentage , germination vigor , germination index , and radicle length of seedlings after seven days of germination under water stress .

The soaking with 1 mM of NaCl exhibited most the pronounced effects on improving seed germination and alleviating stress damage .

NaCl-induced seeds germination and growth could be associated with the increases in endogenous gibberellic acid ( GA ) and indole-3-acetic acid ( IAA ) levels through activating amylases leading to improved amylolysis under water stress .

Seedlings pretreated with NaCl had a significantly lower osmotic potential than untreated seedlings during seed germination , which could be related to significantly higher soluble sugars and free proline content in NaCl-treated seedlings under water stress .

For antioxidant metabolism , NaCl pretreatment mainly improved superoxide dismutase , peroxidase , ascorbate peroxidase , and glutathione reductase activities , transcript levels of FeSOD , APX , and DHAR , and the content of ascorbic acid , reduced glutathione , and oxidized glutathione during seed germination under water stress .

The results indicated that seeds soaking with NaCl could remarkably enhance antioxidant metabolism , thereby decreasing the accumulation of reactive oxygen species and membrane lipid peroxidation during germination under water stress .

In addition , NaCl-upregulated dehydrin-encoded genes SK2 expression could be another important mechanism of drought tolerance during seeds germination of white clover in response to water stress .


Sulfur-containing compounds play an important role in plant stress defense ; however , only a little is known about the molecular mechanisms of regulation of sulfate assimilation by stress .

Using known Arabidopsis ( Arabidopsis thaliana ) mutants in signaling pathways , we analyzed regulation of the key enzyme of sulfate assimilation , adenosine 5'-phosphosulfate reductase ( APR ) , by salt stress .

APR activity and mRNA levels of all three APR isoforms increased 3-fold in roots after 5 h of treatment with 150 mm NaCl .

The regulation of APR was not affected in mutants deficient in abscisic acid ( ABA ) synthesis and treatment of the plants with ABA did not affect the mRNA levels of APR isoforms , showing that APR is regulated by salt stress in an ABA-independent manner .

In mutants deficient in jasmonate , salicylate , or ethylene signaling , APR mRNA levels were increased upon salt exposure similar to wild-type plants .

Surprisingly , however , APR enzyme activity was not affected by salt in these plants .

The same result was obtained in mutants affected in cytokinin and auxin signaling .

Signaling via gibberellic acid , on the other hand , turned out to be essential for the increase in APR mRNA by salt treatment .

These results demonstrate an extensive posttranscriptional regulation of plant APR and reveal that the sulfate assimilation pathway is controlled by a complex network of multiple signals on different regulatory levels .


Protease inhibitors ( PIs ) function in the precise regulation of proteases , and are thus involved in diverse biological processes in many organisms .

Here , we studied the functions of the Arabidopsis UNUSUAL SERINE PROTEASE INHIBITOR ( UPI ) gene , which encodes an 8.8 kDa protein of atypical sequence relative to other PIs .

Plants harboring a loss-of-function UPI allele displayed enhanced susceptibility to the necrotrophic fungi Botrytis cinerea and Alternaria brassicicola as well as the generalist herbivore Trichoplusia ni .

Further , ectopic expression conferred increased resistance to B. cinerea and T. ni .

In contrast , the mutant has wild-type responses to virulent , avirulent and non-pathogenic strains of Pseudomonas syringae , thus limiting the defense function of UPI to necrotrophic fungal infection and insect herbivory .

Expression of UPI is significantly induced by jasmonate , salicylic acid and abscisic acid , but is repressed by ethylene , indicating complex phytohormone regulation of UPI expression .

The upi mutant also shows significantly delayed flowering , associated with decreased SOC1 expression and elevated levels of MAF1 , two regulators of floral transition .

Recombinant UPI strongly inhibits the serine protease chymotrypsin but also weakly blocks the cysteine protease papain .

Interestingly , jasmonate induces intra- and extracellular UPI accumulation , suggesting a possible role in intercellular or extracellular functions .

Overall , our results show that UPI is a dual-specificity PI that functions in plant growth and defense , probably through the regulation of endogenous proteases and/or those of biotic invaders .


Abscisic acid ( ABA ) , auxins , cytokinins , gibberellic acid , alone or in combination were tested for their effects on short-term sucrose uptake in sugar beet ( Beta vulgaris cv USH-20 ) roots .

The effect of ABA on active sucrose uptake varied from no effect to the more generally observed 1.4-to 3.0-fold stimulation .

A racemic mixture of ABA and its trans isomer were more stimulatory than ABA alone .

Pretreating and/or simultaneously treating the tissue with K(+ ) or IAA prevented the ABA response while cytokinins and gibberellic acid did not .

While the variable sensitivities of beet root to ABA may somehow be related to the auxin and alkali cation status of the tissue , tissue sensitivity to ABA was not correlated with ABA uptake , accumulation , or metabolic patterns .

In contrast to ABA , indoleacetic acid ( IAA ) and other auxins strongly inhibited active sucrose uptake in beet roots .

Cytokinins enhanced the auxin-induced inhibition of sucrose uptake but ABA and gibberellic acid did not modify or counteract the auxin effect .

Trans-zeatin , benzyladenine , kinetin , and gibberellins had no effect on active sucrose uptake .

None of the hormones or hormone mixtures tested had any significant effect on passive sucrose uptake .

The effects of IAA and ABA on sucrose uptake were detectable within 1 h suggesting a rather close relationship between the physiological activities of IAA and ABA and the operation of the active transport system .


Ascochyta blight of lentil is an important fungal disease in many lentil-producing regions of the world causing major yield and grain quality losses .

Quick shifts in aggressiveness of the population of the causal agent Ascochyta lentis mandates developing germplasm with novel and durable resistance .

In the absence of complete resistance , lentil genotypes CDC Robin and 964a-46 have frequently been used as sources of partial resistance to ascochyta blight and carry non-allelic ascochyta blight resistance genes .

RNA-seq analysis was conducted to identify differences in the transcriptome of CDC Robin , 964a-46 and the susceptible check Eston after inoculation with A. lentis .

Candidate defense genes differentially expressed among the genotypes had hypothetical functions in various layers of plant defense , including pathogen recognition , phytohormone signaling pathways and downstream defense responses .

CDC Robin and 964a-46 activated cell surface receptors ( e.g. receptor like kinases ) tentatively associated with pathogen-associated molecular patterns ( PAMP ) recognition and nucleotide-binding site leucine-rich repeat ( NBS-LRR ) receptors associated with intracellular effector recognition upon A. lentis infection , and differed in their activation of salicylic acid , abscisic acid and jasmonic acid / ethylene signal transduction pathways .

These differences were reflected in the differential expression of downstream defense responses such as pathogenesis-related proteins , and genes associated with the induction of cell death and cell-wall reinforcement .

A significant correlation between expression levels of a selection of genes based on quantitative real-time PCR and their expression levels estimated through RNA-seq demonstrated the technical and analytical accuracy of RNA-seq for identification of genes differentially expressed among genotypes .

The presence of different resistance mechanisms in 964a-46 and CDC Robin indicates their value for pyramiding gene leading to more durable resistance to ascochyta blight .


Hydrogen sulfide ( H(2)S ) is a gasotransmitter and signaling molecule associated with seed germination , plant growth , organogenesis , photosynthesis , stomatal conductance , senescence , and post-harvesting .

H(2)S is produced in plants via both enzymatic and non-enzymatic pathways in different subcellular compartments .

Exogenous application of H(2)S facilitates versatile metabolic processes and antioxidant machinery in plants under normal and environmental stresses .

This compound interacts with phytohormones like auxins , abscisic acid , gibberellins , ethylene , jasmonic acid , and salicylic acid .

Furthermore , H(2)S participates in signal transductions of other signaling molecules like nitric oxide , carbon monoxide , calcium , methylglyoxal , and hydrogen peroxide .

It also mediates post-translational modification , which is a protective mechanism against oxidative damage of proteins .

This review summarizes the roles of H(2)S as intriguing molecule in plants .


Histone acts as the core for nucleosomes and is a key protein component of chromatin .

Among different histone variants , histone H3 ( HH3 ) variants have been reported to play vital roles in plant development .

However , biological information and evolutionary relationships of HH3 genes in cotton remain to be elucidated .

The current study identified 34 HH3 genes in Gossypium hirsutum .

Phylogenetic analysis classified HH3 genes of 19 plant species into eight distinct clades .

Sequence logos analysis among Arabidopsis , rice , and G. hirsutum amino acid residues showed higher conservation in amino acids .

Using collinearity analysis , we identified 81 orthologous/paralogous gene pairs among the four genomes ( A , D , At , and Dt ) of cotton .

Further , orthologous/paralogous and the Ka/Ks ratio demonstrated that cotton HH3 genes experienced strong purifying selection pressure with restricted functional divergence resulting from segmental and whole genome duplication .

Expression pattern analysis indicated that GhHH3 genes were preferentially expressed in cotton ovule tissues .

Additionally , GhHH3 gene expression can be regulated by abiotic stresses ( cold , heat , sodium chloride ( NaCl ) , and polyethylene glycol ( PEG ) ) and phytohormonal ( brassinolide ( BL ) , gibberellic acid ( GA ) , indole-3-acetic acid ( IAA ) , salicylic acid ( SA ) , and methyl jasmonate ( MeJA ) ) treatments , suggesting that GhHH3 genes might play roles in abiotic and hormone stress resistance .

Taken together , this work provides important information to decipher complete molecular and physiological functions of HH3 genes in cotton .


The major programs of gene expression during late embryogenesis are the muturation or reserve accumulation program and , after ovule abscission , the postabscission program that is composed largely of Lea and LeaA mRNAs that probably encode desiccation protectants .

There are diverse opinions about the developmental regulators of these programs .

Several candidates are evaluated here by measuring , in cultured embryos , the accumulation kinetics of cloned mRNAs specifically expressed in the normal maturation , postabscission , or germination programs of cotton .

Maturation-stage embryos both terminate the maturation program and induce the postabscission program after excision and culture , just as they do later in the plant after ovule abscission .

However , they also induce simultaneously the germination program and are thus different from any normal stage of embryo development or germination .

The developmental induction of the postabscission program in culture does not require exogenous abscisic acid , but its expression is enhanced by precocious desiccation or culture on abscisic acid or high osmoticum , probably by an environmentally responsive mechanism that normally operates during germination .

Normal desiccation does not control any of these programs because the embryo acquires all of the characteristics of a mature embryo before it desiccates .

These and other results suggest regulation of normal embryogenesis by a maternal maturation factor , a postabscission factor , and the postabscission program .


The effects of ethephon as a sugarcane ripener are attributed to ethylene .

However , the role of this phytohormone at the molecular level is unknown .

We performed a transcriptome analysis combined with the evaluation of sucrose metabolism and hormone profiling of sugarcane plants sprayed with ethephon or aminoethoxyvinylglycine ( AVG ) , an ethylene inhibitor , at the onset of ripening .

The differential response between ethephon and AVG on sucrose level and sucrose synthase activity in internodes indicates ethylene as a potential regulator of sink strength .

The correlation between hormone levels and transcriptional changes suggests ethylene as a trigger of multiple hormone signal cascades , with approximately 18 % of differentially expressed genes involved in hormone biosynthesis , metabolism , signalling , and response .

A defence response elicited in leaves favoured salicylic acid over the ethylene/jasmonic acid pathway , while the upper internode was prone to respond to ethylene with strong stimuli on ethylene biosynthesis and signalling genes .

Besides , ethylene acted synergistically with abscisic acid , another ripening factor , and antagonistically with gibberellin and auxin .

We identified potential ethylene target genes and characterized the hormonal status during ripening , providing insights into the action of ethylene at the site of sucrose accumulation .

A molecular model of ethylene interplay with other hormones is proposed .


Exposure of plants to toxic concentrations of metals leads to disruption of the cellular redox status followed by an accumulation of reactive oxygen species ( ROS ) .

ROS , like hydrogen peroxide , can act as signaling molecules in the cell and induce signaling via mitogen-activated protein kinase ( MAPK ) cascades .

MAPK cascades are evolutionary conserved signal transduction modules , able to convert extracellular signals to appropriate cellular responses .

In this review , our current understanding about MAPK signaling in plant metal stress is discussed .

However , this knowledge is scarce compared to research into the role of MAPK signaling in the case of other abiotic and biotic stresses .

ROS production is a common response induced by different stresses and undiscovered analogies may exist with metal stress .

Therefore , further attention is given to MAPK signaling in other biotic and abiotic stresses and its interplay with other signaling pathways to create a framework in which the involvement of MAPK signaling in metal stress may be studied .


Plants under stress from both biotic and abiotic sources produce increased levels of ethylene , which is perceived by ethylene receptors and triggers cellular responses further downstream .

Protein phosphorylation and dephosphorylation were implicated in the regulation of ethylene induction by stresses based on studies using protein kinase and phosphatase inhibitors .

However , the kinase(s ) involved remains to be determined .

Using a conditional gain-of-function transgenic system , we demonstrate that the activation of SIPK , a tobacco mitogen-activated protein kinase ( MAPK ) , by NtMEK2DD , an active mutant of the upstream kinase of SIPK , resulted in a dramatic increase in ethylene production .

The increase in ethylene after the activation of SIPK coincided with a dramatic increase in 1-aminocyclopropane-1-carboxylic acid ( ACC ) synthase ( ACS ) activity , which was followed by the activation of a subgroup of ACS and ACC oxidase ( ACO ) genes , suggesting that either the activation of unidentified ACS(s ) or post-transcriptional regulation is involved .

Infection with Tobacco mosaic virus ( TMV ) , which is known to activate the SIPK cascade and induce ethylene biosynthesis , also induced the same ACSs and ACOs .

After ethylene production in NtMEK2DD plants , strong activation of ETHYLENE-RESPONSE FACTOR ( ERF ) genes was observed , similar to the effect in NN tobacco plants infected with TMV .

In contrast to previous reports , no major increase in jasmonic acid ( JA ) and methyl jasmonate ( MJ ) was detected after the activation of SIPK/WIPK in NtMEK2DD transgenic plants .

These results suggest that the induction of ethylene but not JA/MJ is involved in plant defense responses mediated by the NtMEK2-SIPK/WIPK pathway .


We conducted a study of the patterns and dynamics of oxidized fatty acid derivatives ( oxylipins ) in potato leaves infected with the late-blight pathogen Phytophthora infestans .

Two 18-carbon divinyl ether fatty acids , colneleic acid and colnelenic acid , accumulated during disease development .

To date , there are no reports that such compounds have been detected in higher plants .

The divinyl ether fatty acids accumulate more rapidly in potato cultivar Matilda ( a cultivar with increased resistance to late blight ) than in cultivar Bintje , a susceptible cultivar .

Colnelenic acid reached levels of up to approximately 24 nmol ( 7 microgram ) per g fresh weight of tissue in infected leaves .

By contrast , levels of members of the jasmonic acid family did not change significantly during pathogenesis .

The divinyl ethers also accumulated during the incompatible interaction of tobacco with tobacco mosaic virus .

Colneleic and colnelenic acids were found to be inhibitory to P. infestans , suggesting a function in plant defense for divinyl ethers , which are unstable compounds rarely encountered in biological systems .


We studied the localization of 6-phosphogluconate dehydrogenase ( PGD ) isoforms of Arabidopsis ( Arabidopsis thaliana ) .

Similar polypeptide lengths of PGD1 , PGD2 , and PGD3 obscured which isoform may represent the cytosolic and/or plastidic enzyme plus whether PGD2 with a peroxisomal targeting motif also might target plastids .

Reporter-fusion analyses in protoplasts revealed that , with a free N terminus , PGD1 and PGD3 accumulate in the cytosol and chloroplasts , whereas PGD2 remains in the cytosol .

Mutagenesis of a conserved second ATG enhanced the plastidic localization of PGD1 and PGD3 but not PGD2 .

Amino-terminal deletions of PGD2 fusions with a free C terminus resulted in peroxisomal import after dimerization , and PGD2 could be immunodetected in purified peroxisomes .

Repeated selfing of pgd2 transfer (T-)DNA alleles yielded no homozygous mutants , although siliques and seeds of heterozygous plants developed normally .

Detailed analyses of the C-terminally truncated PGD2 - 1 protein showed that peroxisomal import and catalytic activity are abolished .

Reciprocal backcrosses of pgd2 - 1 suggested that missing PGD activity in peroxisomes primarily affects the male gametophyte .

Tetrad analyses in the quartet1 - 2 background revealed that pgd2 - 1 pollen is vital and in vitro germination normal , but pollen tube growth inside stylar tissues appeared less directed .

Mutual gametophytic sterility was overcome by complementation with a genomic construct but not with a version lacking the first ATG .

These analyses showed that peroxisomal PGD2 activity is required for guided growth of the male gametophytes and pollen tube-ovule interaction .

Our report finally demonstrates an essential role of oxidative pentose-phosphate pathway reactions in peroxisomes , likely needed to sustain critical levels of nitric oxide and/or jasmonic acid , whose biosynthesis both depend on NADPH provision .


Redox processes regulate plant/insect responses , but the precise roles of environmental triggers and specific molecular components remain poorly defined .

Aphid fecundity and plant responses were therefore measured in Arabidopsis thaliana mutants deficient in either catalase 2 ( cat2 ) , different protein phosphatase 2A ( PP2A ) subunits or glutathione ( cad2 , pad2 , and clt1 ) under either moderate ( 250 μmol m(-2 ) s(-1 ) ) or high ( 800 μmol m(-2 ) s(-1 ) ) light .

Aphid fecundity was decreased in pp2a-b'γ , cat2 and the cat2 pp2a-b'γ double mutants relative to the wild type under moderate irradiance .

High light decreased aphid numbers in all genotypes except for cat2 .

Aphid fecundity was similar in the cat2 and glutathione- , phytoalexin- , and glucosinolate-deficient cat2cad2 double mutants under both irradiances .

Aphid-induced increases in transcripts encoding the abscisic acid-related ARABIDOPSIS ZINC-FINGER PROTEIN 1 transcription factor were observed only under moderate light .

Conversely , aphid induced increases in transcripts encoding the jasmonate-synthesis enzyme ALLENE OXIDE CYCLASE 3 was observed in all genotypes only under high light .

Aphid-induced increases in REDOX RESPONSIVE TRANSCRIPTION FACTOR 1 mRNAs were observed in all genotypes except pp2a-b'ζ1 - 1 under both irradiances .

Aphid fecundity is therefore regulated by cellular redox signalling that is mediated , at least in part , through PP2A-dependent mitochondria to nucleus signalling pathways .


The features of the formation of microshoots in in vitro culture of Silene cretacea — endangered species with narrow ecological amplitude , which is a promising source of medicinal raw materials — were studied .

It was demonstrated that , at the micropropagation step , basic Woody Plant Medium containing vitamins according to Murashige and Skoog and supplemented with 0.2 mg/L 6-benzylaminopurine , 1.0 mg/L kinetin , 1.0 mg/L gibberellic acid , and 0.5 mg/L indole-3-acetic acid is the most effective .

The combination and concentration of these growth regulators , selected using mathematical combinatorial analysis , activated axillary buds and provided a high multiplication factor ( 9.3 ± 1.3 microshoots per explant ) .

Morpho-histological analysis revealed the main stages of the formation of microshoots and proved the absence of callus formation during the whole time of the cultivation of explants .

The features of the dynamics of the culture during the year of continuous cultivation are presented .


Mutant T66 was isolated from 450 mutants ( constructed with Agrobacterium tumefaciens-mediated transformation method ) of Trichoderma harzianum .

Maize seeds coated with T66 were more susceptible to Curvularia lunata when compared with those coated with wild-type ( WT ) strain .

The disease index of maize treated with T66 and WT were 62.5 and 42.1 % , respectively .

Further research showed T-DNA has inserted into the ORF of one gene , which resulted in the functional difference between WT and T66 .

The gene was cloned and named Thc6 , which encodes a novel 327 amino acid protein .

To investigate its function , we obtained knockout , complementation , and overexpression mutants of Thc6 .

Challenge inoculation studies suggested that the Thc6 overexpression mutant can reduce the disease index of maize inbred line Huangzao 4 against the leaf spot pathogen ( C. lunata ) .

Meanwhile , The Thc6 mutants were found to affect the resistance of maize inbred line Huangzao 4 against C. lunata by enhancing the activation of jasmonate-responsive genes expression .

Liquid chromatography-mass spectrometry ( LC-MS ) data further confirmed that the concentration of jasmonate in the induced maize exhibits a parallel change tendency with the expression level of defense-related genes .

Hence , the Thc6 gene could be participated in the induced resistance of maize inbred line Huangzao 4 against C. lunata infection through a jasmonic acid-dependent pathway .


Bisphenol A ( BPA ) is an endocrine disruptor that is ubiquitous in the environment .

Previous studies have focused on the effects of BPA on plants to assess the ecological risk of BPA in the environment .

To evaluate the effects of BPA on plant biological characters more systematically , we investigated the biological characters of above-ground and under-ground organs of soybean plants exposed to BPA .

Meanwhile , the mechanisms for the observed changes were also analyzed from the view of hormone levels and photosynthesis .

The results showed that after exposure to 0.8 mg L(-1 ) BPA for three days , indole-3-acetic acid ( IAA ) and gibberellic acid levels in roots increased significantly , and the IAA level increased in leaves , so the character indices of roots and leaves both increased .

The IAA and ethylene levels in stems increased , but the character indices of stems did not increased .

With higher BPA concentrations , especially exposure to 17.2 mg L(-1 ) BPA , the levels of IAA , gibberellic acid , and zeatin decreased ( except for the increased zeatin in leaves ) , and abscisic acid and ethylene levels increased ; thus , all of the character indices significantly decreased .

By comparing the changes in various biological characters , we found that leaf area , root surface area , and root length changed most significantly .

In addition , changes in photosynthetic parameters provided initial causes for plant growth changes , and impacted biological characters .

The changes of character indices were stronger when the BPA exposure time was prolonged , and after the removal of BPA , the character indices showed some recovery .

Therefore , BPA exposure can regulate the changes in plant characters by influencing hormone levels and photosynthesis , and root surface area , root length , and leaf area were the most sensitive to BPA .