Two New Species of Protocedroxylon Gothan(Pinaceae) from the Middle Jurassic of Eastern Inner Mongolia, NE China

Two new coniferous wood taxa, Protocedroxylon zhangii sp. nov. and P. zhalantunense sp. nov., are described from the Middle Jurassic Wanbao Formation in Zhalantun City, Inner Mongolia, NE China. The new discovery represents the first record of petrified wood in the Wanbao Formation, and contributes to further understanding the floral composition, especially that of the forest, of the Wanbao Formation. Anatomically, the two new species are characterized by having a mixed type of radial pitting and Abietineentüpfelung. In extant conifers, Abietineentüpfelung is considered to be characteristic of the wood of Pinaceae. The new discovery further indicates that the first occurrence of Abietineentüpfelung in conifer-like wood should be earlier than the Kimmeridgian. The palaeolatitudinal distribution pattern of Protocedroxylon indicates that the genus is a palaeobiogeographically consistent group, which was probably restricted to wetter and cooler temperate climates. In combination with distinct growth rings, the occurrence of Protocedroxylon suggests that a cool temperate and seasonal climate might have prevailed during the sedimentation period of the Wanbao Formation in eastern Inner Mongolia, NE China. Such a view is also in agreement with the palaeoclimatic conditions indicated by the plant megafossils of the Wanbao Formation.

Essential Oil Composition of Six Pinus L. Taxa （Pinaceae） from Canada and Their Chemotaxonomy

In this study six Pinus L. taxa from Canada （P. strobus L., P. parviflora Siebold ＆ Zucc., P. mugo Turra subsp, mugo, P. resinosa Sol. ex Alton, P. flexilis E. James and P. nigra J. F. Arnold） were studied to determine on chemical characters of studied taxa. For this purpose, essential oil from needles of the six Pinus taxa were investigated by HS-SPME/GC-MS. 38, 33, 39, 28, 31 and 46 compounds were respectively identified from each species representing 95.90%, 95.07%, 95.79%, 96.20%, 93.05% and 96.25% of the oil. The results have given some clues on the chemotaxonomy of this genus and are of usable potentials of the plants as renewable resources. Although the essential oil composition of studied taxa showed chemical divergences because of climatical, seasonal, geographical and geological factors, but the major compounds of plant derivatives are generally similar and the major compounds are chemotaxonomical markers for studied taxa.

Identification of Essential Oil Composition of Four Picea Mill, （Pinaceae） Species from Canada

The aim of this study was to determine the volatile composition of essential oil of four Picea Mill. species （Piceapungens Engelm., Picea mariana （Mill.） Britton, Picea glauca （Moench） Voss., Picea rubens Sarg.） needles. The volatile components extracted from these four species needles were analyzed by using headspace solid phase microextraction （HS-SPME）/gas chromatography-mass spectrum （GC-MS） and 31, 34, 27 and 24 compounds were identified representing 91.77%, 92.70% 92.38% and 94.06% of the total oil, respectively. The major constituents were found to be bornylacetate （29.40%）, camphor （26.43%）, 13-myrcene （7.47%） and camphene （7.01%） in P. pungens; camphene （22.03%）, bornylacetate （21.64%）, α-pinene （16.62%） and borneol （7.79%） in P. mariana; bornylacetate （31.25%）, limonene （17.27%）, α-pinene （15.85%）; camphene （13.65%） in P. glauca and borneol （12.38%）, α-pinene （10.36%）, germacrene D （9.86%） and δ-cadinene （8.25%） in P. rubens. This study sought to detecte new phytochemical data on the Picea genus to help chemotaxonomy and usable of studied species.

Litterfall production modeling based on climatic variables and nutrient return from stands of Eucalyptus grandis Hill ex Maiden and Pinus taeda L.

Native grasslands in the Pampas of South America are increasingly being replaced by Eucalyptus and Pinus stands.The short rotation regimes used for the stands require high nutrient levels,with litterfall being a major source of nutrient return.To model the litterfall production using climatic variables and assess the nutrient return in 14-year-old Eucalyptus grandis and Pinus taeda stands,we measured litter production over 2 years,using conical litter traps,and monitored climatic variables.Mean temperature,accumulated precipitation,and mean maximum vapor pres-sure deficit at the seasonal level influenced litterfall produc-tion by E.grandis;seasonal accumulated precipitation and mean maximum temperature affected litterfall by P.taeda.The regression tree modeling based on these climatic vari-ables had great accuracy and predictive power for E.grandis(N=33;MAE(mean absolute error)=0.65;RMSE(root mean square error)=0.91;R^(2)=0.71)and P.taeda(N=108;MAE=1.50;RMSE=1.59;R^(2)=0.72).The nutrient return followed a similar pattern to litterfall deposition,as well as the order of importance of macronutrients(E.grandis:Ca>N>K>Mg>P;P.taeda:N>Ca>K>Mg>P)and micronutrients(E.grandis and P.taeda:Mn>Fe>Zn>Cu)in both species.This study constitutes a first approximation of factors that affect litterfall and nutrient return in these systems.

Cloning of sft-4 and its influence on vitality and virulence of pine wood nematode,Bursaphelenchus xylophilus

In our previous screening of the transcriptome of the causal agent of the devastating pine wilt disease,pine wood nematode(PWN,Bursaphelenchus xylophilus),after treatment with the nematicide fomepizole,Surfeit locus gene sft-4,which encodes a regulatory factor,was found to be downregulated.In situ hybridization results showed that the sft-4 was continuously expressed from egg to adult and was especially high in the reproductive system.Here in a study of the effect of RNA interference(RNAi)of sft-4 and recombinant SFT-4 on PWN activity,treatment with sft-4 dsRNA inhibited feeding,reproduction,oviposition and egg hatching of PWN with the greatest inhibition on reproduction and oviposition,whereas recombinant SFT-4 had the opposite effect.In addition,RNAi of sft-4 changed the female–male ratio and lifespan of PWN.In bioassays of PWNs,with RNAi of sft-4 on seedlings and 2-year-old Pinus thunbergii trees,none of the treated plants developed symp-toms during the monitoring period,indicating that virulence of PWNs was either significantly weakened.These results indicate that the influence of sft-4 on PWN pathogenicity may be mainly through regulating reproductive function of PWN and its lifespan.

基于8hm^2样地的天山云杉林蒸腾耗水从单株到林分的转换

为了准确地估算天山北坡中部天山云杉森林的林分蒸腾耗水量,设置了8hm2固定样地,在每木调查的基础上,通过对7株标准木连续晴天液流的观测,得到胸径与液流速率和胸径与边材面积的拟合方程,最终计算得到了林分的蒸腾耗水量,确定了估算该森林群落蒸腾耗水的最小取样面积,并且讨论了最小取样面积随样地位置的变化。结果表明:①在自然生长系,天山云杉林分最大蒸腾耗水量、平均蒸腾耗水量同种植密度呈Extrem函数分布;当种植密度达到1200株/hm2时,林分最大蒸腾耗水量达到最大,为77.27 t/hm2d;②对林分蒸腾耗水量的测算存在明显的最小取样面积,最小取样面积随取样点的不同而略有差异,取样起始点在本8hm2固定样地的上线和下线处时最小取样面积为4hm2,取样起始点在本8hm2固定样地的中部时最小取样面积为2.56hm2,这对于更加精确地估算天山北坡天山云杉森林的蒸腾耗水量提供了理论依据。

A New Species of the Extinct Genus Schizolepis from the Jurassic Daohugou Flora,Inner Mongolia,China with Special Reference to the Fossil Diversity and Evolutionary Implications

Schizolepis daohugouensis sp. nov. is described from the Jurassic sediments of Daohugou flora, from Ningcheng County, Inner Mongolia Autonomous Region, China. The female cone is slender, cylindrical in shape, seed scale complexes are loosely and helically arranged on the cone axis at intervals of 3-5 mm. The seed scales are bilobed and divided almost from the base; the scales have no evident petiole but an articulation at the region of attachment to the cone axis. Each lobe of the seed scales is oval in shape, widest at the lower middle part; lobes are obtusely pointed with entire margins. Bract scale is fan shaped. Based on the records of Schizolepis, this is the first report of the occurrence of female cone of Schizolepis with the seed scales, the winged seeds and vegetative branches preserved together in the Jurassic deposits. The new discovery provides evidence that confirms the phylogenetic position of Schizolepis to the extant Pinaceae.

Development of ecoregion-based merchantable volume systems for Pinus brutia Ten. and Pinus nigra Arnold. in southern Turkey

Estimating individual tree volume is one of the essential building blocks in forest growth and yield models. Ecologically based taper equations provide accurate vol- ume predictions and allow classification by mer- chantable sizes, assisting in sustainable forest management. In the present study, ecoregion-based compatible volume systems for brutian pine and black pine in the three ecoregions of southern Turkey were developed. Several well-known taper functions were evaluated. A second- order continuous-time autoregressive error structure was used to correct the inherent autocorrelation in the hierar- chical data, allowing the model to be applied to irregularly spaced and unbalanced data. The compatible segmented model of Fang et al. （For Sci 46：1-12, 2000） best described the experimental data. It is therefore recommended for estimating diameter at a specific height, height to a specific diameter, merchantable volume, and total volume for the three ecoregions and two species analyzed. The nonlinearextra sum of squares method indicated differences in ecoregion and tree-specific taper functions. A different taper function should therefore be used for each pine spe- cies and ecoregion in southern Turkey. Using ecoregion- specific taper equations allows making more robust esti- mations and, therefore, will enhance the accuracy of diameter at different heights and volume predictions.

Regeneration patterns in Mexican pine-oak forests

Background: Global change is causing an increase in the incidence of natural and anthropogenic disturbances on forests, which frequently interact synergistically and promote changes in forest structure, composition and functioning. In this study we evaluate the regeneration of Pinaceae and Fagaceae species in pure and mixed stands in Mexico to determine if current regeneration patterns are indicative of changes in the relative dominance of these two tree families, as observed in other temperate regions. We also identify the environmental factors that determine the regeneration patterns of Pinaceae and Fagaceae species in these forests.Results: We use data from two consecutive surveys of the National Inventory of Forests and Soils of Mexico(INFyS),obtained in 2004–2009 and 2009–2014. Our results show that the spatial patterns of regeneration are affected by forest structure, by climate, by the type and intensity of disturbances and by land tenure. Importantly, the presence and abundance of Fagaceae regeneration is generally higher than that of Pinaceae, and tends to be favoured(relative to Pinaceae) under warmer climates and by the presence of wildfires.Conclusions: The higher regeneration of Fagaceae relative to Pinaceae under warmer and fire-prone conditions could have important impacts on the composition and functioning of Mexican temperate forests under ongoing climate change, as well as affect their resilience to future disturbances.

Fertility variation in endemic populations of Ehrami black pine (Pinus nigra Arnold. subsp. pallasiana var. pyramidata)

Fertility variation and effective number of parents were estimated in the 100 individuals from each of three plantation populations (P1, P2 and P3) of the endangered Pinus nigra. subsp. pallasiana var. pyramidata established in the Isparta-Golcuk district in southern Turkey in 1990. Potential relations between cone yield and growth characters (height, diameter at breast height, diameter at base and crown diameter) were also investigated. Large differences were found among populations and within populations for cone production and growth characters. Mean cone production was eight (ranging from 6.5 in P2 to 9.1 in P1) for the three populations. The 10 most productive individuals for cones produced 32% of the total cones in P1, 39% in P2 and 34% in P3; 21, 16 and 6 individuals, respectively did not produce any cones in the populations. According to the correlation analyses, the relation between cone yield and growth characters changed for the populations, while height, diameter at breast height and crown diameter were positively significantly correlated (r = 0.182, 0.135 and 0.209; p ≤ 0.05) with cone production for the three populations. Fertility variation was 1.81 in total of three populations, ranging from 1.72 in P3 to 3.45 in P1). Effective number of parents was 142 (55.2 of number of parents censused; 29%, P1; 49.8%, P2; 58.3%, P3).

Problems in the Field of Systematics and Investigation of Conifers in Russia

The largest and most important family in Russian conifers is Pinaceae （27-29 species）. The most important problems in the field of systemitics concern some critical taxa. In the result of author＇s research, the new signs of vegetative and reproductive organs have been checked out and elaborated. It leads to the clarifying of new taxonomic status and geographical distribution of certain critical taxa. A set of species are threatened and need special measures which are included into the Red Data Book of Russian Federation. for their conservation. There are 13 species and one variety

Cytotoxic terpenes from Abies sibirica

One new and 16 known compounds were isolated from Abies sibirica. Their structures were assigned mainly on the basis of NMR and MS spectroscopic data. In bioassay for anti-proliferative activity against four human tumor cells, compound 7 exhibited selective anti-proliferative activity against COLO-205 tumor cell with an IC50 value of 0.9 μg/mL.

Forrestiacids C and D,unprecedented triterpene-diterpene adducts from Pseudotsuga forrestii

Forrestiacids C(1)and D(2),a pair of C-25 epimeric triterpene–diterpene adducts were isolated from the needles and twigs of the vulnerable conifer Pseudotsuga forrestii.This unprecedented class of compounds might be generated via an intermolecular Michael addition reaction of a rearranged 6/6/5/5-fused spiro-lanostene with an abietene.Their structures were established by spectroscopic data and X-ray crystallography.The adducts showed inhibitory activities against the ATP-citrate lyase(ACL)and acetyl-CoA carboxylase 1(ACC1),two rate-limiting enzymes in the de novo lipogenesis pathway.

PALEONTOLOGY (2)PALEOBOTANY

20082462 Huang Pin(Nanjing Institute of Geology and Palaeontology,Chinese Acade- my of Sciences,Nanjing 210008,China);Li Jianguo Sporopollen Assemblages from the Xishanyao and Toutunhe Formations at the Honggou Section of the Manasi River,Xin- jiang and Their Stratigraphical Significance (Acta Micropalaeontologica Sinica,ISSN 1000—0674,CN32—1189/Q,24(2),2007,p. 170—193,1 illus.,3 tables,4 plates,59 refs.) Key words:palynological assemblage, biostratigraphy,Xinjiang The Honggou section is located at