Analysis of mitochondrial DNA of an endangered beech species,Fagus hayatae Palibin ex Hayata

Mitochondrial DNA restriction fragment length polymorphisms were used to examine cytoplasmic diversity within a relic-like population of Fagus hayatae, located in northern Taiwan. Fifteen trees were surveyed for three restriction endonucleases (BamHI, EcoRI and HindIII) and five mitochondrial gene probes (atpA, atp6, atp9, coxI and coxII). The analysis failed to reveal any polymorphisms, an observation that suggests cytoplasmic uniformity in the F. hayatae population examined. It is also interesting to note that the chondriome type of our F. hayatae samples is very close to that characteristic of F. crenata populations in the southernmost area of Japan.     

Effects of radial growth rate on selected indices for juvenile and mature wood of the Japanese larch

To examine the differences between juvenile and mature wood, 12 aged sample trees from two areas of Nagano Prefecture were harvested; and the radial development of tracheid length, the ring density, and the relation of the radial growth rate (observed by ring width) with some selected indices of ring structure were investigated. The results proved that the radial variation of tracheid length with ring number can be described by a logarithmic formula, and both plantations reached the demarcation of juvenile and mature wood at age 18. With the segmented regression method, we also analyzed radial variation of mean density and found that the demarcation of juvenile and mature wood was at age 15 for sample trees from Saku and at age 21 for those from Yabuhara. By using the results of estimates from juvenile and mature wood based on ring density, we found that high growth rates resulted when producing lower-density wood during the juvenile period, but these rates did not occur during the mature period. The basic reason for this phenomenon is the variation in patterns of earlywood and latewood in juvenile and mature wood, respectively. This result advised us that when managing plantations of Japanese larch it is necessary to take different measurements at different growth periods.     

农牧交错带人工草地放牧对奶牛生产性能的影响

研究不同放牧制度和强度对在“多年生禾草+紫花苜蓿(Medicago sativa)”人工草地上放牧奶牛的采食量、产奶量、乳成分及体重和体况分的影响。结果表明:轮牧制奶牛的采食量低于连续放牧制,中度放牧低于轻度放牧。轻度轮牧有较高的体增重和较小的体况分损失,连续放牧则相反。轮牧制奶牛的产奶量显著高于连续放牧制,中牧高于轻牧。不同放牧处理对乳成分的影响不显著,轻度轮牧的乳脂率低于中度轮牧和连续放牧,轻度轮牧的乳蛋白最高,乳糖和乳干物质含量则无显著变化。     

Relationship Between Coleoptile Length and Drought Resistance and Their QTL Mapping in Rice

By using a set of recombinant inbred line(RIL)population involving in 195 lines derived from a cross of Zhenshan 97B (lowland variety)and IRAT109(upland variety),the correlation analysis between coleoptile length(CL)and drought resistance index (DRI)and their QTL identification were conducted.There existed a significantly positive relationship between CL and DRI with the correlation coefficient of 0.2206**under water stress conditions.Under normal and water stress conditions,a total of eleven and four QTLs for CL and DRI,respectively,were detected on chromosomes 1,2,4,5,6,7,9,11 and 12 by using a linkage map including 213 SSR markers,which explained 4.84%to 22.65%of phenotypic variance.Chromosomes 1 and 9 possessing the QTLs for DRI harbored simultaneously QTLs for CL,and qCL9 shared the same chromosome location with qDRI9(RM160-RM215).Comparing the QTLs related to drought resistance in other studies,QTLs for CL and DRI were located in the same or adjacent marker interval as those related to root traits,such as number,dry weight,depth,and length of root.Moreover,sixteen and three pairs of epistatic loci for CL and DRI were found,which accounted for 56.17%and 11.93%of the total variation in CL and DRI,respectively.     

Mapping of a New Gene Wbph6（t） Resistant to the Whitebacked Planthopper, Sogatella furcifera, in Rice

A rice population consisting of 90 TN1/Guiyigu F3 lines was employed to analyze the linkage between DNA markers and a new gene Wbph6(t) conferring resistance to whitebacked planthopper, Sogatella furcifera By using the mapping approach of bulked extremes and recessive class, Wbph6(t) was mapped onto the short arm of chromosome 11 with a genetic distance of 21.2 cM to SSLP marker RM167.     

构筑乌江生态屏障打造余庆秀美山川

余庆县于2004年3月荣获"全国绿化模范县"光荣称号,这是对余庆绿化成绩的充分肯定。       

台州城市林业建设存在问题、对策及设想(下)

最近,台州市委市政府提出实现林业现代化的宏伟目标,要实现林业现代化,必须首先实现城市林业现代化,如果没有发达的城市林业作支撑,就根本谈不上实现林业现代化。文章针对台州实际,提出台州城市林业建设指导思想、原则、目标、具体内容及措施等新思路,为保障台州城市建设可持续发展和生态市建设提供生态参考。       

长春森林文化建设

创建"森林城"的理念与成功实践,在文化领域把森林文化与汽车文化、电影文化、教育文化及建筑文化紧密结合形成具有鲜明地域特色的长春森林文化,亦是长春市的城市名片。解读长春森林文化还让我们从一个绿色广场谈起。       

南粤大地一明珠——花城锦绣出奇景云山珠水泛绿舟

城市化进程中的广州面临着城市污染和城市病日愈加重的挑战。解决温饱后的广州人目前最关心的是生态环境的改善。人们已经认定最佳的生态环境是森林,最便捷的生活环境是功能齐备的城市,只有森林与城市两者融合才是理想的人居生活环境。市政府清楚的认识到改善城市生态环境对促进经济可持续发展的重要性,森林是陆地生态系统的主体,城市森林建设是改善城市生态环境的突破口。广州市林业局在市府的正确领导下,在营造"城在林中,林在城中"这一伟大生态工程中狠下功夫,以人为本,作了许多实实在在的顺应民意的事。现将主要成绩、基本经验和今后打算简介如下。       

绿色屏障护京城

如果你在北京能够生活上一年以上时间,你会被北京三季有花、四季常青景色所吸引,你会为绿色和鲜花带来的温馨而陶醉。作为生活在北京的一员,我感受到了身边绿年色环境的变换,也为北京的这种变化而骄傲。