Genome wide investigation of Hsf gene family in Phoebe bournei:identification,evolution,and expression after abiotic stresses

Heat shock transcription factors(Hsfs)have important roles during plant growth and development and responses to abiotic stresses.The identification and func-tion of Hsf genes have been thoroughly studied in various herbaceous plant species,but not woody species,especially Phoebe bournei,an endangered,unique species in China.In this study,17 members of the Hsf gene family were identi-fied from P.bournei using bioinformatic methods.Phyloge-netic analysis indicated that PbHsf genes were grouped into three subfamilies:A,B,and C.Conserved motifs,three-dimensional structure,and physicochemical properties of the PbHsf proteins were also analyzed.The structure of the PbHsf genes varied in the number of exons and introns.Pre-diction of cis-acting elements in the promoter region indi-cated that PbHsf genes are likely involved in responses to plant hormones and stresses.A collinearity analysis dem-onstrated that expansions of the PbHsf gene family mainly take place via segmental duplication.The expression levels of PbHsf genes varied across different plant tissues.On the basis of the expression profiles of five representative PbHsf genes during heat,cold,salt,and drought stress,PbHsf pro-teins seem to have multiple functions depending on the type of abiotic stress.This systematic,genome-wide investigation of PbHsf genes in P.bournei and their expression patterns provides valuable insights and information for further func-tional dissection of Hsf proteins in this endangered,unique species.

Effect of Environmental Gradients on the Quantity and Quality of Fallen Logs in Tsuga longibracteata Forest in Tianbaoyan National Nature Reserve, Fujian Province,China

We investigated the quantity and quality 0f fallen l0gs in different Tsuga l0ngibracteata f0rest c0mmunities in the Tianba0yan Nati0nal Nature Reserve. We used redundancy analysis t0 determine the spatial distributi0n 0f fallen l0gs in the different f0rest c0mmunities and t0 analyze the relati0nships am0ng stand structure, t0p0graphic fact0rs and human disturbance. The v0lume, c0vered area, mean l0g length and number 0f fallen l0gs differed significantly am0ng f0rest types （P 〈 0.05）, but mean diameter at breast height sh0wed n0 significant difference （P 〉 0.05）. The l0g v0lume and c0vered area in different f0rest types sh0wed the f0ll0wing trend： T. l0ngibracteata pure f0rest 〈 T. l0ngibracteata ＋ Olig0staehyum scabrifl0rur 〈 T. l0ngibraeteata ＋ hardw00d 〈 Rh0d0dendr0n simiarum ＋ T. l0ngibraeteata 〈 T. l0ngibraeteata ＋ Phyll0stachys heter0cycla pubescens. The spatial distributi0n patterns 0f l0gs quantity and quality indicated that l0g v0lume and c0vered area were str0ngly affected by envir0nmental fact0rs in the f0ll0wing 0rder： human disturbance 〉 elevati0n 〉 sl0pe p0siti0n 〉 b0le height 〉 tree height 〉 sl0pe aspect 〉 density 〉 basal area 〉 sl0pe gradient. The relative c0ntributi0n 0f envir0nmental variables 0n the t0tal variance was t0p0graphy （76%） 〉 disturbance （42%） 〉 stand structure （35%）. T0p0graphy and disturbance c0mbined explained 8.2% 0f the variance. Fallen l0~s auantitv and aualitvwere negatively related t0 elevati0n and sl0pe p0siti0n, and p0sitively ass0ciated t0 human disturbance. The l0g v0lume decreased fr0m n0rthern t0 s0uthern sl0pes. Envir0nmental fact0rs had the highest impact 0n class I （slightly decayed）, and l0west impact 0n class V （highly decayed）.

Effects of forest cover types and environmental factors on soil respiration dynamics in a coastal sand dune of subtropical China

Trees on sand dunes are more sensitive to environmental changes because sandy soils have extremely low water holding capacity and nutrient availability. We investigated the dynamics of soil respiration(Rs) for secondary natural Litsea forest and plantations of casuarina,pine, acacia and eucalyptus. Results show that significant diurnal variations of Rsoccurred in autumn for the eucalyptus species and in summer for the pine species, with higher mean soil respiration at night. However, significant seasonal variations of Rswere found in all five forest stands. Rschanged exponentially with soil temperatures at the 10-cm depth; the models explain 43.3–77.0% of Rs variations. Positive relationships between seasonal Rsand soil moisture varied with stands. The correlations were significant only in the secondary forest, and the eucalyptus and pine plantations. The temperature sensitivity parameter(Q10 value) of Rsranged from 1.64 in casuarina plantation to 2.32 the in secondary forest; annual Rswas highest in the secondary forest and lowest in the pine plantation. The results indicate that soil temperatures and moisture are the primary environmental controls of soil respiration and mainly act through a direct influence on roots and microbial activity. Differences in root biomass, quality of litter,and soil properties(pH, total N, available P, and exchangeable Mg) were also significant factors.

In vitro propagation of a medicinal plant: Tripterygium wilfordii Hook f.

In this study a reliable protocol was developed for the establishment of commercial in vitro cultures of Tripterygium wilfordii Hook f.. Juvenile shoots from one-year-old elite plants were used as the source of explants. New axillary shoots were obtained after 30 days of culture on a MS medium supplemented with BAP （2.0 mg.L^-1） and NAA （0.1 mg.L^-1）. The optimal multiplication medium was a modified MS medium supplemented with BAP （1.0 mg.L^-1） and NAA （0.1 mg.L^-1）. This yielded a multiplication rate of 2.4 for each subculture. Slightly more than 92% of shoots rooted when cultured on a modified MS medium containing IBA （0.2 mg.L^-1） and activated charcoal （0.5 mg.L^-1）. Activated charcoal promoted both a strong and a high rooting rate during the rooting phase. Plantlets were transferred to pots for a short acclimatization stage in a greenhouse where 95% of the plantlets survived. This highly reproducible procedure can be adopted for large-scale propagation of T. wilfordii.

Spatio-temporal Variation of Landscape Heterogeneity under Influence of Human Activities in Xiamen City of China in Recent Decade

Xiamen is an economically competitive and highly urbanized city along the coastal area of Fujian Province, China. The research on spatio-temporal variation of landscape heterogeneity under the influence of human activities is of great importance to the further study on the relationship of landscape pattern and ecological process. It is also crucial to the discovery of spatial variation and intensity distribution of human activities. The research analyzed the intensity of human impacts and the spatial variation features and dynamics of landscape patterns by introducing statistical theories and approaches. We analyzed spatio-temporal variation of landscape heterogeneity using the geostatistical techniques, such as semivariogram and Kriging interpolation.Results show that there is a higher correlation between landscape heterogeneity indexes and human impact index. Both the indexes show a moderate spatial autocorrelation as well as an obvious characteristic of anisotropy. From 1998 to 2008, the spatial differentiation of the changes in the intensity of human activities and the changes in landscape heterogeneity shows that the landscape patterns in Xiamen are closely related with the urban land utilization methods, the condition of traffic and geographical location and the physical geographical condition such as the terrain and the ecological environment. The process of urbanization has a significant impact on the urban landscape pattern.

The Effects on the Cutting Propagation of Cinnamomum micranthum in Different Seasons

Cinnamomum micranthum is one of China Third-class Endangered Tree Species. The seedlings of C. micranthum are difficult to obtain. It is important to study the cutting propagation of C. micranthum in different seasons to improve the rooting rate for providing seedling propagation technique for the afforestation industry. In this study,the optimal season for the cutting propagation of C. micranthum was summer( May),providing 80. 6% rooting rate. The rooting rate in Summer was 33. 4% higher than that in Spring( March). This technique is important to make the best use of rare C. micranthum resources and to provide plenty of seedlings for afforestation and greening industry.

Improvement of the tissue culture technique for Melaleuca alternifolia

Tea tree oil is extracted from the leaves and twigs of Melaleuca alternifolia （Maiden ＆ Betche） Cheel, and it is widely used in medicines, food preservatives, cosmetics and health care products. Traditional propagation of M. alternifolia from seeds does not necessarily transfer the desired characteristics from their mother trees, the seedlings are not uniform, and the multiplication rate from cuttings is relatively low. For these reasons, it is necessary to develop tissue culture techniques for this species. This study showed that an efficient explant initiation medium for M. alternifolia was MS 1/2 ＋ BA 0.6mg L^-1 ＋NAA 0.1 mg L^-1＋sucrose 30g L-l, which yielded a 75.9 % initiation rate. An efficient multi- plication medium was MS ＋ BA 0.3 mg L^-1＋ NAA 0.15 mg L^-1 ＋ sucrose 30 g L^-1, which yielded a 4.3 multiplication rate and 3.2 cm shoot length. The rooting medium was MS 1/2 ＋ IBA 0.1-0.25 mg L^-1 ＋ sucrose 15 g L^-1, which yielded a 100 % rooting rate, 2.94-3.32 roots per individual and 1.36-1.44 cm root length. Local red-core soil was suitable as a transplant medium, and yielded 98 % survival. This study improved the tissue culture technique for mass-propagation of M. alternifolia, enabling the production of high quality plants for market.

In Vitro Propagation of Ardisia mamillata Hance

Ardisia mamillata Hance is a rare plant with highly ornamental and medicinal value. The traditional propagation methods for A. mamillata by seeds or cutting provided low proliferation rate. This study is to optimize the propagation technique of A. mamillata by tissue culture and set up an industrial production system to provide plenty of A. mamillata seedlings for the human demand. The optimal initiation medium for A. mamillata is MS +2.0 mg/L BA +0.1 mg/L NAA +30 g/L sugar, providing76.4% initiation rate. The optimal shoot proliferation medium for A. mamillata is MS+1.0 mg/L BA+0.1 mg/L NAA+30 g/L sugar, providing 4.56 fold proliferation rate and3.10 cm shoot in height. The optimal shoot elongation medium for A. mamillata is MS+0.5 mg/L BA+0.1 mg/L NAA+30 g/L sugar, providing 2.77 fold proliferation rate and 4.27 cm shoot in height. The optimal rooting medium for A. mamillata is 1/2MS+0.1 mg/L IBA +15 g/L sugar, providing 99.7% rooting rate, 4.0 roots per individual,7.53 cm root in length and 3.94 cm shoot in height. This provides a reliable mass propagation method for A. mamillata.

Comparison of the Effects of Pesticide Application on Biston suppressaria Larvae in Different Damage Stages

[Objective] The paper was to determine the optimal control period of Biston suppressaria, the most serious defoliator in eucalyptus forests in southern Fujian Province. [Method] By spraying 2% abamectin + Bacilus thuringiensis powder in the forest, the first generation larvae of B. suppressaria was controlled in the early damage stage(May 2), middle damage stage(May 13) and late damage stage(May 30), respectively.[Result] When 500 g of pesticide was sprayed per 667 m^(2) in the early damage stage of the first generation larvae, the population reduction rate was97.5 % at 5 d post spraying. When 500 g of pesticide was sprayed per 667 m^(2) in the middle damage stage, the population reduction rate was 95.3% at 5 d post spraying. When 1 000 g of pesticide was sprayed per 667 m^(2) in the late damage stage, the population reduction rate was 83.9%, conspicuously lower than those in the early and middle damage stage. If pesticides were sprayed in the early and middle damage stage, the second gen-eration larvae would not cause harms, but the second generation larvae would cause slight harms if pesticides were sprayed in the late damage stage.[Conclusion] Control before the middle damage stage has significant effect on improving the control effect and reducing losses while reducing the usage of pesticides.

Correlation between Inclusion Contents in Casuarina spp. Twigs and Its Resistance to Lymantria xylina

[ Objective ] The paper was to explore the correlation between inclusion contents in Casuarina spp. twigs and its resistance to Lymantria xylina. [ Method] Three types of representative Casuar/na spp. strains including resistant strains （Zhanjiang 3, Hui 76, Hui 83, Guangdong A8-2）, moderate resistant strains （Pingtan 2, Hui 1, Long 7-18） and susceptible strains （Dongshan 2, Guangdong 501, Kang[eng） were tzst~ as materials to determine the contents of six kinds of inclusions, total phenol, tannin, flavonoids, protein, soluble sugar and polysaccharide. [ Result] The resistant strains had higher flavonaids, tannin and total phenol contents and lower soluble sugar and protein contents than the susceptible strains, while the content of polysaccharide acted randomly. The grey correla- tivity analysis showed that resistance degree, pupation rate and pupal weight had high correlation with protein and soluble sugar contents, with correlation index equal to or above 0.500 0. [ Conclusion] The study provided a theoretical basis for screening and promotion of resistant strains against L xylina.