Genetic Diversity of Indocalamus Determined by Chloroplast DNA Sequence

[Objective]The aim was to research the relationship and genetic diversity of Indocalamus.[Method]Using 13 samples of Indocalamus and 3 samples of Sasa as materials,the intergenic regions of trnL-trnF gene in chloroplast were amplified by PCR,and sequence analysis and phylogenetic trees construction were carried out.[Result]Using the universal primer,the intergenic regions of trnL-trnF were amplified,the lengths of the segments varied from 1 008 bp to 1 103 bp,of which 940 bp was compared.The dendrogram of trnL-trnF sequences showed that Indocalamus and Sasa were clustered together and they were homologous by 99%.All the samples were divided into five groups,the first group included 12 samples such as Indosalamus pedalis,I.pumilus,I.victorialis,I.longiauritus,I.tessellatus,Sasa sinica,Sasa pygmaea,I.barbatus,I.guangdongensis,I.herklotsii,I.Hirtivaginatus and S.fortunei.I.decorus,I.lacunosus,I.Latifolius and I.Migoi were respectively divided into four groups.[Conclusion]The high homology of all samples showed the low evolution speed and little information sites which suggested that the phylogeny of Indocalamus could not be well resolved by the intergenic region of trnL-trnF.

Effects of key growth conditions on endogenous hormone content in tillering stem bases,germination of lateral buds,and biomass allocation in Indocalamus decorus

Physiological responses and changes in growth of Indocalamus decorus Q.H.Dai under different ecological conditions are essential for further understanding growth regulation and adaptive mechanisms and establishing an evidence-based management system for optimal growth. In this study, the endogenous hormone content in tillering stem bases, germination of lateral buds, and biomass allocation of this bamboo species in different growth environments were investigated. Among the endogenous hormones in the basal stems of tillers, indole-3-pyruvic acid and zeatin riboside were highly correlated with lateral buds that germinated to form shoots, while gibberellic acid was highly correlated with lateral buds that germinated to form rhizomes. The best lateral bud germination characteristics were achieved with full sun, a density of six plantlets per pot, and watering every 6 days. I. decorus plantlets used different resource allocation strategies depending on treatment. Different ecological factors influenced endogenous hormones in the bamboo stem base,which affected lateral bud germination and biomass allocation.

Community features of Indocalamus wilsoni in the Shennongjia Na-tional Nature Reserve, China

Four vegetation types, namely coniferous and broadleaved mixed forest, secondary deciduous broadleaved forest, open shrubs and meadow, with dwarf bamboo (Indocalamus wilsoni) are compared on their floristic composition, life form, community structure, and survivorship of bamboos. Disturbance of conifer-logging two decades ago promoted the species diversity, but negatively influenced the survivorship of dwarf bamboo which is dominate on the forest floor. Open shrubs bear more species diversity and more geophytes in its life-form spectrum than its background vegetation subalpine meadow, however, dwarf bamboo is growing much better in the open shrubs than in the meadow. It seems dwarf bamboo probably favorites to occur in the vegetation at gentle slopes with a mediate canopy cover. Its mass flowering in the secondary deciduous forest suggests that a simultaneous flowering and following dieback maybe irrupt in the recently coming years over the subalpine Shennongjia in China, which will be not only alter the floristic composition and community structure of the old bamboo stands, but also influence the survivorship of this rare species.

Comprehensive analyses of inhibition of the Chinese traditional food-packaging materials,Indocalamus latifolius leaves(Zongye)on Aspergillus flavus

Objectives:The contamination of Aspergillus flavus and aflatoxins(AFs)is one of the most serious safety problems in food and feed.The discovery and application of plant-sourced antifungal agents are hot topics in mycotoxin control.In this study,we aim to develop efficient strategies to control A.flavus and subsequent contamination by AFs.Materials and Methods:We focused on Zongye essential oil,which was extracted from Indocalamus latifolius leaves(Zongye,the traditional food-packaging materials).Its antifungal and antitoxin activities were observed by volatile test,and the significant morphological and ultrastructural variations were observed by scanning electron microscopy(SEM)and transmission electron microscopy(TEM)analyses.The main components of Zongye essential oil were analyzed by gas chromatography-mass spectrometry(GC-MS).RNA sequencing(RNA-Seq)and real-time quantitative reverse transcription polymerase chain reaction(qRT-PCR)analyses were used to reveal the inhibitory mechanism.Results:Among them,No.2 Zongye essential oil completely inhibited the growth and toxin production of A.flavus after 10μL treatment.Under Zongye essential oil treatment,evidently morphological and ultrastructural variations were observed,such as hyphae shrinkage,partial distortion,and a decrease in conidia number.Longifolene and linalool were the major constituents of Zongye essential oil,accounting for 9.55% and 7.95%,respectively,and linalool had stronger inhibitory effects on fungal growth and mycotoxin biosynthesis than longifolene.Based on the experimental results,the antifungal mechanism was proposed:down-regulations of membrane proteins(AFLA_005560,AFLA_019420,and AFLA_084310,etc.)and conidial genes(fblC,steA,and abaA,etc.)inhibited fungal development,and anti-aflatoxigenic activity might be due to significant down-regulation of AF clustergenes andglobal regulators(AtfA and AtfB).Conclusion:A novel antifungal agent,Zongye essential oil,was identified,and its inhibitory mechanism was comprehensively clarified,which is helpful to control AF contamination in an environmentally friendly way.