Antimicrobial peptide (AMP) from Zingiber zerumbet rhizomes with inhibitory effect on Pythium myriotylum secretory proteases and zoospore viability.

Protease mediated proteolysis has been widely implicated in virulence of necrotrophic fungal pathogens. This is counteracted in plants by evolving new and effective antimicrobial peptides (AMP) that constitute important components of innate immune system. Peptide extraction from rhizome of Zingiber zerumbet was optimized using ammonium sulphate (50-80% w/v) and acetone (60 and 100% v/v) with maximal protein recovery of 1.2 ± 0.4 mg/g obtained using 100% acetone. Evaluation of inhibitory potential of Z. zerumbet rhizome protein extract to prominent hydrolases of necrotrophic Pythium myriotylum revealed maximal inhibition of proteases (75.8%) compared to other hydrolytic enzymes. Protein was purified by Sephacryl S200HR resin resulting in twofold purification and protease inhibition of 84.4%. Non-reducing polyacrylamide gel electrophoresis (PAGE) of the fractions yielded two bands of 75 kDa and 25 kDa molecular size. Peptide mass fingerprint of the protein bands using matrix assisted laser desorption/ionization (MALDI)-time of flight (TOF) mass spectroscopy (MS) and subsequent MASCOT searches revealed peptide match to methylesterase from Arabidopsis thaliana (15%) and to hypothetical protein from Oryza sativa (98%) respectively. Further centrifugal filter purification using Amicon Ultra (10,000 MW cut-off) filter, yielded a prominent band of 25 kDa size. Concentration dependent inhibition of zoospore viability by Z. zerumbet AMP designated as ZzAMP was observed with maximal inhibition of 89.5% at 4 µg protein and an IC50 value of 0.59 µg. Studies are of particular relevance in the context of identifying the molecules involved in imparting below ground defense in Z. zerumbet as well in development of AMPs as potential candidate molecules for control of necrotrophic pathogens of agricultural relevance.

Genome-Wide Analysis and Characterization of the Aux/IAA Family Genes Related to Floral Scent Formation in Hedychium coronarium.

Auxin plays a key role in different plant growth and development processes, including flower opening and development. The perception and signaling of auxin depend on the cooperative action of various components, among which auxin/indole-3-acetic acid (Aux/IAA) proteins play an imperative role. In a recent study, the entire Aux/IAA gene family was identified and comprehensively analyzed in Hedychium coronarium, a scented species used as an ornamental plant for cut flowers. Phylogenetic analysis showed that the Aux/IAA gene family in H. coronarium is slightly contracted compared to Arabidopsis, with low levels of non-canonical proteins. Sequence analysis of promoters showed numerous cis-regulatory elements related to various phytohormones. HcIAA genes showed distinct expression patterns in different tissues and flower developmental stages, and some HcIAA genes showed significant responses to auxin and ethylene, indicating that Aux/IAAs may play an important role in linking hormone signaling pathways. Based on the expression profiles, HcIAA2, HcIAA4, HcIAA6 and HcIAA12, were selected as candidate genes and HcIAA2 and HcIAA4 were screened for further characterization. Downregulation of HcIAA2 and HcIAA4 by virus-induced gene silencing in H. coronarium flowers modified the total volatile compound content, suggesting that HcIAA2 and HcIAA4 play important roles in H. coronarium floral scent formation. The results presented here will provide insights into the putative roles of HcIAA genes and will assist the elucidation of their precise roles during floral scent formation.

Actinomycetes: an unexplored microorganisms for plant growth promotion and biocontrol in vegetable crops.

Actinomycetes, a Gram positive bacteria, well reported as a source of antibiotics, also possess potential to control various plant pathogens, besides acting as plant growth promoting agent. Chemicals in different forms are extensively being used in vegetable farming, adversely affecting the environment and consumer health. Microbial agent like actinomycetes can substantially replace these harmful chemicals, and have now started finding a place as an important input in to farming practices. Only selected vegetable crops belonging to 11 different families have been explored with use of actinomycetes as biocontrol and plant growth promoting agent till now. It provides ample opportunities to vegetable researchers, to further explore with use of this very important group of microorganisms, in order to achieve even higher production level of safe vegetables. Mycostop and Actinovate are two actinomycetes based formulations globally available for use in vegetable farming as a substitute for chemical formulations. Present review article has summarized the literature available on use of actinomycetes in vegetable farming. Existing wide gap in knowledge, and potential thrust areas for future research have also been projected.

Genetic structure and relationships within and between cultivated and wild korarima [Aframomum corrorima (Braun) P.C.M. Jansen] in Ethiopia as revealed by simple sequence repeat (SSR) markers.

BACKGROUND: Korarima [Aframomum corrorima (Braun) P.C.M. Jansen] is a spice crop native to Ethiopia. Understanding the extent and partitioning of diversity within and among crop landraces and their wild relatives is among the first steps in conserving and measuring their genetic potential. The present study is aimed at characterizing the population genetic structure and relationships between cultivated and wild korarima in the southwestern part of Ethiopia. RESULTS: We analyzed a total of 195 individuals representing seven wild and fourteen cultivated populations. Eleven polymorphic simple sequence repeat (SSR) markers were used. We observed a total of 53 alleles across the eleven loci and individuals. In total, 32 alleles were detected in the cultivated populations, whereas 49 alleles were detected in the wild populations. We found higher genetic diversity in wild populations than in the cultivated counterpart. This result implies the potential of wild korarima as a possible source for novel alleles contributing to the improvement of cultivated korarima. Analysis of molecular variance (AMOVA) showed significant but low differentiation between cultivated and wild korarima populations. Similarly, neighbour-joining and STRUCTURE analyses did not group cultivated and wild populations into two distinct clusters. The lack of clear differentiation between cultivated and wild populations could be explained by historical and contemporary gene flow between the two gene pools. CONCLUSION: The 11 SSR loci developed in this study could be employed to examine genetic diversity and population structure of korarima in other countries as well as other Aframomum species. From the five administrative zones considered in this study, the Bench-Magi and Sheka zone showed populations with high genetic diversity, and these populations could be used as a potential starting point for in-situ and ex-situ germplasm conservation and korarima improvement through breeding programs after proper agronomic evaluation.

Variation in secondary metabolite production as well as antioxidant and antibacterial activities of Zingiber zerumbet (L.) at different stages of growth.

BACKGROUND: Zingiber zerumbet (L.) is a traditional Malaysian folk remedy that contains several interesting bioactive compounds of pharmaceutical quality. METHODS: Total flavonoids and total phenolics content from the leaf, stem, and rhizome of Z. zerumbet at 3 different growth stages (3, 6, and 9 months) were determined using spectrophotometric methods and individual flavonoid and phenolic compounds were identified using ultra-high performance liquid chromatography method. Chalcone Synthase (CHS) activity was measured using a CHS assay. Antioxidant activities were evaluated by ferric reducing antioxidant potential (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays. The antibacterial activity was determined against Gram-positive and Gram-negative bacteria using the disc diffusion method. RESULTS: Highest content of total flavonoid [29.7 mg quercetin equivalents (QE)/g dry material (DM)] and total phenolic (44.8 mg gallic acid equivalents (GAE)/g DM) were detected in the rhizome extracts of 9-month-old plants. As the plant matured from 3 to 9 months, the total flavonoid content (TFC) and total phenolic content (TPC) decreased in the leaf, but increased significantly in the rhizomes. Among the secondary metabolites identified, the most abundant, based on the concentrations, were as follows: flavonoids, catechin > quercetin > rutin > luteolin > myricetin > kaempferol; phenolic acids, gallic acid > ferulic acid > caffeic acid > cinnamic acid. Rhizome extracts from 9-month-old plants demonstrated the highest CHS activity (7.48 nkat/mg protein), followed by the 6-month-old rhizomes (5.79 nkat/mg protein) and 3-month-old leaf (4.76 nkat/mg protein). Nine-month-old rhizomes exhibited the highest DPPH activity (76.42 %), followed by the 6-month-old rhizomes (59.41 %) and 3-month-old leaves (57.82 %), with half maximal inhibitory concentration (IC50) of 55.8, 86.4, and 98.5 µg/mL, respectively, compared to that of α- tocopherol (84.19 %; 44.8 µg/mL) and butylated hydroxytoluene (BHT) (70.25 %; 58.6 µg/mL). The highest FRAP activity was observed in 9-month-old rhizomes, with IC50 of 62.4 µg/mL. Minimal Inhibitory Concentration (MIC) of Z. zerumbet extracts against Gram-positive and Gram-negative bacteria ranged from 30 to >100 µg/mL. Among the bacterial strains examined, Staphylococcus aureus was sensitive to the leaf extract of Z. zerumbet, with MIC of 30.0 µg/mL and other strains were sensitive to the rhizome extracts. CONCLUSIONS: Three- and 9-month-old plants are recommended when harvesting the leaf and rhizome of Z. zerumbet, respectively, in order to obtain effective pharmaceutical quality of the desired compounds.

Molecular phylogenetics and anti-Pythium activity of endophytes from rhizomes of wild ginger congener, Zingiber zerumbet Smith.

Zingiber zerumbet, a perennial rhizomatous herb exhibits remarkable disease resistance as well as a wide range of pharmacological activities. Towards characterizing the endophytic population of Z. zerumbet rhizomes, experiments were carried out during two different growing seasons viz., early-June of 2013 and late-July of 2014. A total of 34 endophytes were isolated and categorized into 11 morphologically distinct groups. Fungi were observed to predominate bacterial species with colonization frequency values ranging from 12.5 to 50%. Among the 11 endophyte groups isolated, molecular analyses based on ITS/16S rRNA gene sequences identified seven isolate groups as Fusarium solani, two as F. oxysporum and one as the bacterium Rhizobium spp. Phylogenetic tree clustered the ITS sequences from Z. zerumbet endophytes into distinct clades consistent with morphological and sequence analysis. Dual culture assays were carried out to determine antagonistic activity of the isolated endophytes against Pythium myriotylum, an economically significant soil-borne phytopathogen of cultivated ginger. Experiments revealed significant P. myriotylum growth inhibition by F. solani and F. oxysporum isolates with percentage of inhibition (PoI) ranging from 45.17 ± 0.29 to 62.2 ± 2.58 with F. oxysporum exhibiting higher PoI values against P. myriotylum. Using ZzEF8 metabolite extract, concentration-dependent P. myriotylum hyphal growth inhibition was observed following radial diffusion assays. These observations were confirmed by scanning electron microscopy analysis wherein exposure to ZzEF8 metabolite extract induced hyphal deformities. Results indicate Z. zerumbet endophytes as promising resources for biologically active compounds and as biocontrol agents for soft rot disease management caused by Pythium spp.

Effects of plant growth substances on rooting of Hedychium spicatum under different temperature regimes.

Present study was carried out to develop a simple and efficient vegetative propagation protocol by applying various treatments to rhizome cuttings with different test solutions of auxins and phenolic compound. These were alpha-naphthalene acetic acid (NAA), Indole-3-butyric acid (IBA), Indole Acetic Acid (IAA), phloroglucinol and coumarin. The concentrations for each treatment were 10.0, 50.0 and 100.0 microM. After treatments the rhizome cuttings were planted in polybags containing forest soil and kept under different temperature regimes i.e., inside polyhose (at 20-25 degrees C), inside mist chamber (at 15-20 degrees C) and under nethouse (nursery condition, at 14-18 degrees C). The maximum rooting percentage (74.06%) was achieved at 20-25 degrees C (inside polyhouse) by applying 50.0 microM IBA. Inside poly house condition, the various developmental parameters showed better responses compare to other conditions. On the basis of present study emphasizes that the temperature play a crucial role in rooting and further growth of the plants in this species. By using this simple and significant conventional method of propagation we could be propagate this vulnerable medicinal and aromatic species at large scale for commercial purpose.

Influence of earthworm Eisenia fetida on removal efficiency of N and P in vertical flow constructed wetland.

This study investigates biomass, density, photosynthetic activity, and accumulation of nitrogen (N) and phosphorus (P) in three wetland plants (Canna indica, Typha augustifolia, and Phragmites austrail) in response to the introduction of the earthworm Eisenia fetida into a constructed wetland. The removal efficiency of N and P in constructed wetlands were also investigated. Results showed that the photosynthetic rate (P n), transpiration rate (T r), and stomatal conductance (S cond) of C. indica and P. austrail were (p < 0.05) significantly higher when earthworms were present. The addition of E. fetida increased the N uptake value by above-ground of C. indica, T. augustifolia, and P. australis by 185, 216, and 108 %, respectively; and its P uptake value increased by 300, 355, and 211 %, respectively. Earthworms could enhance photosynthetic activity, density, and biomass of wetland plants in constructed wetland, resulting in the higher N and P uptake. The addition of E. fetida into constructed wetland increased the removal efficiency of TN and TP by 10 and 7 %, respectively. The addition of earthworms into vertical flow constructed wetland increased the removal efficiency of TN and TP, which was related to higher photosynthetic activity and N and P uptake. The addition of earthworms into vertical flow constructed wetland and plant harvests could be the significantly sustainable N and P removal strategy.

Induction of somatic embryogenesis in endangered butterfly ginger Hedychium coronarium J. Koenig.

An efficient protocol has been developed for regeneration of complete plants through somatic embryogenesis in H. coronarium. Creamish white, pale yellow and brown calli were obtained on MS medium supplemented with different concentrations of auxins [2, 4-Dichlorophenoxy acetic acid (2, 4-D), Indole-3 acetic acid (IAA) and 1-Naphthylacetic acid (NAA)] after 4 weeks. Creamy white calli developed on 0.5 mg L(-1) 2, 4-D turned embryogenic when subcultured on basal medium and produced small globular somatic embryos after 6 weeks. Further growth of somatic embryos required their transfer to medium containing 6-benzylaminopurine (BAP) or kinetin (KN). BAP was more effective than KN in promoting shoot proliferation. Maximum shoot length was obtained with 0.5 mg L(-1) BAP whereas maximum shoot number was obtained with 1.0 mg L(-1) BAP. The plantlets thus formed were successfully hardened, and transferred to sand-soil and farm yard manure (1:1:1) with 95% survival.

Ethnomedical uses of Zingiberaceous plants of Northeast India.

AIM OF THE STUDY: Family Zingiberaceae consists of large number of medicinal plants and is well known for its use in ethnomedicine. The objective of this study is to systematically analyse and document the traditional knowledge regarding the use of Zingiberaceous plants for the treatment of various human ailments from NE India, adding information to the valuation of biodiversity and, to forward suggestions for its sustainable use, conservation and for future pharmacological studies. MATERIALS AND METHODS: A survey on the utilization of medicinal plants belonging to Zingibereceae of North-eastern states was carried out by interviewing herbalists followed by collecting plant specimens and identifying the specimen. Ethnobotanical information on traditional plants was catalogued through structured questionnaires in consultations with traditional healers. RESULTS: A total of 34 species were documented belonging to 9 genera of Zingiberaceae for about 25 types of ailments, 67.6% of which were used in curing multiple disorders. Arunachal Pradesh hosts maximum number of Zingiberaceous plant (88%). Rhizomes were found to be the primary plant material as a source for medication and poultices as the predominant mode of preparation. Gastrointestinal conditions (58%) and chest and lungs (41%) related ailments were the main categories for which these plants are used. CONCLUSIONS: The study establishes Zingiberaceae as a medicinal family since 41% of all the available Zingiberaceous plant species in NE were found to possess medicinal value. Some new use of herbs also appeared in this study for the first time.

Caracterização anatômica e fitoquímica de folhas e rizomas de Hedychium coronarium J. Kõnig (Zingiberaceae) / Anatomical and phytochemical characterization of leaves and rhizomes from Hedychium coronarium J. Kõnig (Zingiberaceae)

Devido a grande potencialidade na utilização de Hedychium coronarium, na medicina popular e também como biorremediadora no tratamento de efluentes, objetivou-se uma diagnose dos órgãos, folha e rizoma, para elucidar resultados estruturais e fitoquímicos. A folha é anfiestomática, com predominância de estômatos na face abaxial. Em ambas as superfícies foliares há projeções de cera epicuticular sobre as paredes anticlinais das células epidérmicas. O mesofilo dorsiventral apresenta hipoderme multisseriada (3 camadas) em ambos os lados. O parênquima clorofiliano é diferenciado em paliçádico (1-2 camadas) e lacunoso (4-5 camadas) com muitos espaços intercelulares e ocorrência de idioblastos cristalíferos. Na nervura central, o aerênquima ocorre em único arco na região abaxial. Os feixes vasculares distribuem-se aleatoriamente e são de diferentes tamanhos, pequenos, médios e grandes, envolvidos por fibras. Os feixes menores localizam-se no lado abaxial da nervura. A triagem fitoquímica das folhas mostrou a presença de saponinas e ausência de taninos, antraquinonas, alcalóides e flavonóides. Por meio de Cromatografia em Camada Delgada foram identificadas as presenças de cariofileno e mirceno no óleo essencial bruto obtido a partir das folhas de H. coronarium.

Due to the great potentiality regarding the use of Hedychium coronarium in folk medicine and also as a bioremediator in effluent treatment, this study aimed to diagnose leaf and rhizome in order to elucidate structural and phytochemical results. Hedychium coronarium leaf is amphistomatal, with predominance of stomata on the abaxial surface. On both leaf surfaces, there are epicuticular wax projections over the anticlinal walls from epidermal cells. The dorsiventral mesophyll presents multiseriate (3 layers) hypoderm on both sides. The chlorophyllian parenchyma is differentiated into palisade (1-2 layers) and spongy (4-5 layers) with many intercellular spaces and some crystalliferous idioblasts. In the midrib, the aerenchyma occurs in a single arc on the abaxial surface. The vascular bundles are randomly distributed and present different sizes: small, medium and large, involved by fibers. The smallest bundles are found on the abaxial rib surface. The leaf phytochemical analysis showed the presence of saponins and lack of tannins, anthraquinones, alkaloids and flavonoids. Using thin-layer chromatography, the presence of caryophyllene and myrcene was detected in the crude essential oil obtained from H. coronarium leaves.

Inflorescence and flower development in the Hedychieae (Zingiberaceae): Hedychium coccineum Smith.

The inflorescence of Hedychium coccineum Smith is thyrse, and the primary bracts are initiated in a spiral phyllotactic pattern on the sides of the inflorescence dome. Cincinnus primordia are initiated on the flank of the inflorescence apex, in the axils of primary bracts. This primordium subsequently develops a bract and a floral primordium. Then, the floral primordium enlarges, flattens apically, and becomes rounded. Sepals are initiated sequentially from the rounded corner of the primordium ring sepal initiation, and the floral primordium continues to enlarge and produces a ring primordium. Later, this ring primordium separates three common primordia surrounding a central cavity. The adaxial common primordium is the first separation. This primordium produces the posterior petal and the fertile stamen. The remaining two common primordia separate and produce respectively a petal and a petaloid, the inner androecial member. As the flower enlarges, the cavity of the floral cup becomes a rounded-triangular apex; these apices are the sites of outer androecial primordium initiation. The abaxial outer androecial member slightly forms before the two adaxial members develop. But this primordium ceases growth soon after initiation, while the two posterior primordia continue growth to produce the lateral petaloid staminodes. During this stage, gynoecial initiates in the floral cup and continues to grow until extending beyond the labellum.

Soil fertility and the impact of exotic invasion on microbial communities in Hawaiian forests.

Exotic plant invasions into Hawaiian montane forests have altered many important nutrient cycling processes and pools. Across different ecosystems, researchers are uncovering the mechanisms involved in how invasive plants impact the soil microbial community-the primary mediator of soil nutrient cycling. We examined whether the invasive plant, Hedychium gardnerianum, altered microbial community composition in forests dominated by a native tree, Metrosideros polymorpha, under varying soil nutrient limitations and soil fertility properties within forest plots of the Hawaii long-term substrate age gradient (LSAG). Microbial community lipid analysis revealed that when nutrient limitation (as determined by aboveground net primary production [ANPP]) and soil fertility were taken into account, plant species differentially altered soil microbial community composition. Microbial community characteristics differed under invasive and native plants primarily when N or P was added to the older, highly weathered, P-limited soils. Long-term fertilization with N or P at the P-limited site led to a significant increase in the relative abundance of the saprophytic fungal indicator (18:2 omega 6c,9c) under the invasive plant. In the younger, N-limited soils, plant species played a minor role in influencing soil microbial community composition. We found that the general rhizosphere microbial community structure was determined more by soil fertility than by plant species. This study indicates that although the aggressive invasion of a nutrient-demanding, rapidly decomposable, and invasive plant into Hawaiian forests had large impacts on soil microbial decomposers, relatively little impact occurred on the overall soil microbial community structure. Instead, soil nutrient conditions were more important determinants of the overall microbial community structure within Hawaii's montane forests.

[The disease and its control on zingiberaceous plants in South China Botanical Garden].

The common diseases on the zingiberaceous plants and their occurrence and damage as well as control have been investigated in the ginger garden of South China Botanical Garden recently. The results show that 2 bacterial and 13 fungous diseases are common. To control them effectively, cultural methods such as selecting loose, fertile soil as planting field with good drainage and proper shade; applying healthy and vigor seeds, seedlings and rhizomes for propagation; regulating plant density; fertilizing reasonably, practicing in rotation; irrigating moderately; sanitizing the field opportunity are mostly recommended. The application of chemical and biological pesticides to protect the beneficial organisms is also stressed.