2004 Vol. 17, No. 2
Total 54 seedlets (sources) of 11 exotic alder species were tested on field experiment at Fuyang(120°19′ N,30°12′ E),Zhejiang. All of the 3～4 month-old seedlings of 20 seedlets of five species of Alnus viridis,A.crispa, A.sinuata,A.hirsuta and A.jorullensis, died in summer because of being unable to tolerate the higher temperature and arid weather. Other 6 species of foreign alders were able to survive and grow. Of them, European alder (A.glutinosa) displayed the best, no damage in summer was found,the average heigh of its 4 sources reached to 2.18～2.48 m for two year old seedling, the growth speed was equal to Sichuan alder (A.cremastogyne) . The saw-leaf alder (A.serrulata) grew normally and had no damage too. But red alder (A.rubra) and thin-leaf alder (A.tenuifolia) were seriously injured by high temperature and aridity in summer, leaves scorched and shedding,shoot diebacked, even a few plants died in July to August. Glay alder (A.incana) and tooth-leaf alder (A.rugosa) were lightly damaged in summer. In addition,Taiwan alder (A.formosana) had the longest growing time,it grew rapidly,however it was easy to receive the frost injury in northern Zhejiang. Signifficant differences for some physiological indexes were found among alder species. For European alder, saw-leaf alder and grey alder, the authors could select the fine seed sources to expand the experiment of introducing, European alder might be especially hopeful to be popularized in the plain area of middle and lower reaches of Yangtze River.
Native plant species were studied in the neem(Azadirachta indica) plantation in Yuanmou County of Yunnan by analying the genus areal-types and four diversity indexes (Gleason index,Simpson's diversity index,Shannon-Weiner index and Pielou's evenness index). According to the genus areal-types, the main areal-types were Pantropic and Cosmopolitan, indicating that the tropical component was the most abundant.It was consistant with the climate of the Dry-Hot Valley in Yuanmou County. Four diversity indexes showed the same results: (1)the species richness, diversity indices and evenness declined with the increase of coverage of neem plantation; (2)the number of species and the number of each species were not influenced evidently by the shadow of neem plantation in low coverage(40%),while this influence was very evident in high coverage(40%); (3)the growth of other plant species was restrained by the defoliatation and deadwood of neem in the neem plantation, some species grew very well.
Insect feeding trials were conducted indoors to determine the effects of seed lectins from Robinia pseudoacacia on the utilization and transformation of Lymantria dispar after fed on soaking leaves with the seed lectins.The seed lectins showed significant antimetabolic effects towards fourth larvae of Lymantria dispar and the mortality of larval was high (59%).
The characteristics of lac insect foraging behavior and its preference to host branch in foraging were studied.The results were as follow:when foraging,lac insects move forward,had no choice to moving way,seldom study foraging experience each other,and followed ESS strategy.The ratio of hosted branch below 1 year old was more than 95%,1 to 2 year old was 5%,Kerria lacca hardly hosted on branch over 2 year old.The distribution of lac insects on branches had no relation with orientation.The diameter of hosted branches ranged from 0.47 cm to 1.60 cm,and the ratio of these branches reaches 88%,which diameter ranged from 0.6～1.1 cm.On erect branches,lac insects distributed around the branch,but on most decline branches,lac insects only settled on shaded parts.Comparison anatomy results showed that:the periderm and cortex of 2 year old branch were thicker than that of 1 year old branch,and the layer of sclereids and fibres in 2 year old branch was thicker than that of 1 year old branch by 27 μm.The distance from periderm to phloem of 2 year old branch was farther than that of 1 year old branch.The periderm and cortex of upper parts were thinner than that of basic parts in the same branch.The phloem of sun shined parts was thinner than that of shaded parts in the same branch.Besides these,the keratinization of host tree suberin and tinsel on epiderm also inhibited lac insect foraging.
The effects of Pear-Wheat inter-cropping with big spacing and several rows on water, yields and land utilization in the Huang-Huai-Hai Plain,were studied in this paper. The results indicated that the wheat transpiration in inter-cropping decreased by 21.6% compared to sole wheat field （CK1）.The soil water content in the range of 0.0～3.0 m away from the pear rows decreased but increased away from 6.0～25.0 m. In general, the soil water capacity of 0～200 cm depth and water utilization efficiency by wheat in the inter-cropping increased by 18.1% and 8.7% compared to CK1 repectively. The wheat yields in inter-cropping increased by 6.6% compared to CK1.The land equivalent ration（LER） was 1.19. So, it is feasible that this kind of inter-cropping will be developed in the Huang-Huai-Hai Plain as for the above-mentioned results.
Neem grows well in the hot-dry valley in China, but it is easy to be harmed by cold.The cold resistance of 4 provenances was valued through tissue browning method, membrane fatty acid analysis and the electric conductivity method which Logistic equation was used to determine the inflexion temperature.The results showed that:(1)neem is a plant which has low cold resistance,short cold temperature below 0 ℃ can damage its tender leaves, and 1h temperature below -1 ℃ will lead part of infant seedlings to death; (2) the cold resistant capability has no distinct difference among neem provenances; (3) membrane fatty acid content of leaves has no correlative relation with cold resistance; (4)the medium lethal temperatures of 4 neem provenances are -1.651,-1.675,-1.75,-1.682 ℃.According to the results above-mentioned and the results of freezing experiment, the cold resistance sequence of neem provenances is IND95003IND95004IND95001IND95002.The results showed that it should be careful to import neem to cold zones in China, and IND95003 can be used in the zones with light frost.
Using data from permanent sample plots, this paper studied the dynamics of diameter structure of Chinese fir plantations and affection of density on it, some criterions was adopted such as skewness, kurtosis, variance coefficient, cumulative diameter distribution curves and frequency distribution and so on. The results show:1.In the age range of 6～20,the value of skew changes from negative to positive, the absolute value of skew first gets small,then change to big, at any time, high density stands have the bigger skew, the higher the density of stands is, the earlier the skew varies from negtive to positive;2.The variance law of kurtosis with age is not obvious,kurtosis of stands with low density is bigger than stands with high density, and the value of kurtosis,both of them,tends to 0 at last.3.The diameter variance coefficient shows weakly increasing trendency with age on the whole, and declines in earlier stage,then increases after canopy closure. non-evenness quality of high density stands is relatively big,and the bigger the density is, the earlier the variance coefficient of diameter shows increasing trendency.4.At any range of cumulative frequency distribution,the more smaller the density is, the bigger the middle value of diameter class is, which benefits the formatioin of middle and big wood.5.The size-class distribution testifies these conclusions.
For better understanding the annual and year after year changes and regularities of gutta-percha content in samara of Eucommia ulmoides and for providing scientific theory for effective use of gutta-percha, studies were conducted in 2002 at the experimental demonstration base in Songxian County, Henan Province. Typical sample-tree selection and random selection were applied in this study. Integrated extraction was used to test the gutta-percha content rate. The results showed that gutta-percha content changes in samara could be divided into two stages. The content in kernel and pericarp performed a close relation with the growth of samara, which increased rapidly along with the samara's growth before the samara stopped to grow; while the content increased slowly after the samara's development. The gutta-percha content was in stable among the fruits from different ages of trees. Outstanding production increase was achieved through setting up orchards by grafting female branches on mature trees and by planting grafted saplings. Therefore, high-yield gutta-percha orchard could be established either by planting grafted saplings or by grafting female branches.
Schima superba provenance trails including 36 seed sources from 7 provinces, located at Chun'an City of Zhejiang and Jianou City of Fujian, were used to study geographic variation for 12 seedling characteristics (seedling growth, root character and leaf shape,etc.).The result of variance analysis indicated that there existed significant differences among provenances for nine seedling traits except for taproot length, lateral root length and aged leaf color in late autumn. A classical latitude clinal variation pattern was found for seedling height, leaf character (number, width, thickness), and tender leaf color in late autumn, and the local temperature of seed sources was the main climatic factor which led to the variation pattern. Compared with the northern provenances, the southern ones had higher growth rate and more leaves, however,the leaf became thinner and narrower. Color change of tender leaf of southern provenances was sensitive to cold signal in late autumn. In addition, the precipitation amount of seed sources was main factor effecting phenotypic differences of seed traits. At last, recommended for seedling height, 10 superior provenances were selected respectively for two experimental locations and these provenances almost came from the natural distribution area about at latitude 25° N.
The activation agents were used to treat water-soluble phosphate and be compound to expert fertilizers of Citrus grandis Osbeck and their field biological effect and mechanism were studied on the produce terra of Citrus grandis Osbeck in Meizhou of Guangdong.The results are as follows: (1) The P nutrition of leaves at every growth period of the tree were improved,accordingly the yield and the quality of Citrus grandis were increased markedly when the special fertilizers contained activated phosphate were used to the produce terra of Citrus grandis in Meizhou.(2)The Fe and Mn elements in the lateritic red earth derived from arenaceous shale are closely correlated to the efficiency of P elements. Si can benefit the release of P in soil,and proper Ca also increase the activity of P element.(3)The activation agents can control the release of water-soluble P so as to stabilize the P supply from soil. (4)The lateritic red earth derived from arenaceous shale is the same basalt-latolol soil of other zonality and other mother material as the control mechanisms of activation agents to P is to adjust the contents of Fe,Al and Mn in soil so as to realize the activation of P in soil-plant system.
Taking 6-year-old Choerospondias axillari pure stand and mixed with Cunninghamia lanceolata in different patterns and 5-year-old Choerospondias axillaris stands in different densities as trial sites,the early growth pattern of Choerospondias axillaris,difference of plantation growth on different site conditions,the influence of different planting density on early growth of Choerospondias axillaris,the stand productivity when mixed with Cunninghamia lanceolata in different patterns,the difference of biomass and effect on soil fertility were studied.The results showed that Choerospondias axillaris grew fast in the early stage.On the site with medium fertility,the mean height increment,mean dbh and stock volume of 6-year-old Choerospondias axillaris were 8.53 m,9.74 cm and 86.08 m3 respectively.The growth differences under different site conditions were significant.The influence of planting density on the early growth of Choerospondias axillaris demonstrated the higher the density,the higher the stock volume and the height of branch,and the smaller the crown width.The Choerospondias axillaris stand mixed with Cunninghamia lanceolata could promote the growth of latter and benefit the fertility maintenance.The results showed that the pattern of Choerospondias axillaris and Cunninghamia lanceolata mixed in the ratio of 3∶1 had the highest productivity and biomass,i.e.stock volume 76.42 m3·hm-2,biomass 41.512 7 t·hm-2,which were 74.55% and 97.27% higher compared with that of pure Cunninghamia lanceolata stand respectively.It was proved that this pattern was worth to be extended.
One year old seedlings of baldcypress （Taxodium distichum） were grown in pots under greenhouse conditions with varying soil water contents （W1,flooding;W2,waterlogging;W3,75% of field water capacity;W4,50% of field water capacity;W5,25% of field water capacity） to study the effects of soil water contents on nutrient uptake and allocation of baldcypress. The treatment lasted 130 days, and the results are as follows: （1）The total N concentration of root, stem and leaf of baldcypress increased with increasing of soil water contents, and the total P concentration of root, stem and leaf of W3 among five water treatments was the lowest, flooding or drought stress increased the total P concentration, and the total Ca, K, Na, Mg and Fe concentration in root, stem and leaf had different changing tendency; （2） The order of total N, P, Ca, K, Na, Mg and Fe concentration in root, stem and leaf was in the order of leafrootstem; （3） The total accumulation of nutrients in baldcypress decreased with decreasing of soil water contents, and the allocation ratio of root and stem increased with decreasing of soil water contents, while the allocation ratio of leaf decreased significantly with decreasing of soil water contents.
The variance and genetic analysis results involving 6 Eucalyptus wetarensiss provenances showed that there were highly significant differences in growth and other characteristics among provenances. The heritabilities of provenances and individuals ranged 68.65%～93.45% and 42.20%～82.63% for different characteristics studied, respectively. Growth characteristics were closely correlated with branch size （BR） and under branch height （BH） and crown （CW） except stem form （SF） and the rate of survival (SUR). At an age of 4.5 year old, the mean value of individual volume （SV） of the fastest provenance （No.17931） was 0.089 70 m3 and 1.858 7 times of the worst provenance. The provenance （No.17834） owned the best form characteristics and survival rate. By using synthetical evaluation, three good provenances （No.17834, No.17831 and No.17835） were selected. Meanwhile, the breeding value of all provenances were also estimated.
The mountain vegetation in rocky land of Taihangshan Mountain was studied.Ten kinds of indicators for evaluating soil and water conservation benefit of mountain land vegetation are given on the basis of comprehensive investigation of the typical vegetation. By index mensuration of water-source conservation efficiency and mud-sand analysis in the runoff plot of different vegetation type, it is showed that optimizated vegetation structure with high function of soil and water conservation and water-source conservation construction is important content for vegetation recovery and protective forest system construction in rocky land of Taihangshan Mountain.
An electronic dictionary of English, Latin and Chinese names of tree species (TreeName 1.0) was developed, providing searches for names of tree species, genus and family in any of the three languages. The electronic dictionary contains thousands of names of tree species and brief species descriptions, providing a rapid, accurate and efficient powerful tool as a dictionary for those working with forestry and plant sciences. The software was developed in Visual C++, using dialogue boxes as the search interface and file system based databases as the framework of the software. Flexible function modules were used in the design. In addition to its strong capacity of providing searches, the software was also designed to allow users to create or update their own customizable database of names of tree species. The software can be extended to cover names of plants, animals, birds, insects and any other biological organisms. The software provides incomparable advantages over the traditional printed dictionary.
Field experiments were conducted in Beijing to study the impact of burning, cutting, and chemicals treat on the spreading of Virginia creeper (Parthenocissus quinquefolia). Groundcover and growth vigiour were determined after treatments to assess control efficacy. It was indicted that burning in the early spring could reduce groundcover up to 36.2% in average 30 d to 60 d after burning;Cutting at the basement(0 cm), 20 cm or 40 cm of stem decreased groundcover by 38.2%, 26.7% or 21.9% 50 d after cutting respectively. Applied glyphosate at 1 500 g·hm-2alone or combined 100 g·L-1 glyphosate (750 g·hm-2) with 100 g·L-1 sulfometruon-methyl(75 g·hm-2)strongly inhibited the growth of Parthenocissus quinquefolia,the control efficacy was up to 24%～38%.It was concluded that the risk of Parthenocissus quinquefolia could be managed by using burning, cutting, and some chemicals.
According to the natural characteristics of the hilly region in Tanhang Mountain, the screening trial on the superior species of water soil conservation tree, forage grass,herb adaptable for agroforestry was conducted in order to optimize the agroforestry structure. The results showed that Rhus typhina Nutt.,Robinia pseudoacacia L., Acer truncatum Bge.Ailanthus altissima Swingle,Platycladus orientalis (L.) Franco were the superior species of water soil conservation tree adaptable for agroforestry in the limestone hilly region,and that Medicago sativa L. was the most superior species of forage grass, Pseudostellaria heterophylla Miq., Pinallia ternnata Briet., Blettilla striata (Thunb.) Rchb. f. and Asarum sieboldii Miq. were the superior species of herb.
The results showed that PDA was a more suitable medium for isolation culture of Lactarius hatsutake.Through tissue separation, the pure mycelium could be obtained.When fruit bodies of L. hatsutake from different districts isolated at the same condition, the growth velocity of mycelium was different. Mycelia grew faster on PDA, MMN,Yeast-glucose -gallium,while slowly and weakly on the medium of MS, Cha, and peptone. Using liquid ferment Mycelia of L. hatsutake as inoculum to nursery stock of Masson Pine, mycorrhigal seedling could be formed. Formed mycorhiza could improve the growth of Masson Pine, and achieve the aim of taming culture, which will provide a new way for multi-management of forest production.
A new heart rot pathogen,Phellinus gilvus (Schwein.:Fr.) Pat., was reported from Sichuan of China. It mainly attacked Castanopsis fargesii, and caused a white rot of stem and butt. Its illustrated description was given in detail based on the material from China. The characteristics of the pathogen were provided, and the symptom, damage and distribution of the disease were supplied.
The progress,problems exited and development trends in genetic diversity of phenotype and allozyme in the past 30 years were reviewed.The phenotype diversity was rich,and the variation of morphological characteristics among populations followed certain geographical variation pattern.The genetic parameters at allozyme were as follows:polymorphic loci percentage 23%～84.6%,mean number of alleles per locus 1.33～2.70,expected heterozygosity 0.016～0.306,number of effective alleles 0.23～1.32,gene differentiation coefficient 0.022～0.110.The variation among populations was 2%～13% of the total while the variation within population was 87%～98%.The coupling study was conducted on the genetic diversity of Picea at phenotype,allozyme and DNA levels.The further studies would be focused on the research on the factors influencing genetic diversity and its structure as well as its application in gene resource conservation strategies.
Anoplophora glabripennis, Xylotrechus rusticus,Potosia (Liocola) brivitarsis and Ambrostoma quadriimpressum adults were controlled by injecting 0.8 mL imidacloprid per centimeter DBH on willow, poplar and elm trees in the field.Result showed that 285 adults of A.glabripennis were killed on 15 willow trees in 10 days with 25% imidacloprid insecticide and 281 adults were killed with 15% imidacloprid insecticide under same conditions.724 adulds of P. (Liocola) brivitarsis were killed on 10 willow trees in 10 days with 10% imidacloprid insecticide.50 adults of X.rusticus were killed on 5 poplar trees in 7 days and 146 adulds of A.quadriimpressum were killed on 4 elm trees in 5 days with 25% imidacloprid insecticide.Result showed that imidacloprid insecticide is a high effective systemic for these 4 species of pests.