2005 Vol. 18, No. 2
Michelia chapensis,belonging to Michelia genus in the family Magnoliaceae, is a elite species for timber production and for landscaping. In this paper,the genetic diversity were investigated using RAPD technique.The total DNA were extracted following a modification of CTAB method with some adjustments. A total of 144 individuals representing 6 natural population of M. chapensis were surveyed using 19 RAPD primers.At species level,the percentage of polymorphic bands was 81.98%,Nei's gene diversity was 0.325 5 and Shannon index was 0.475 1.AMOVA showed that 29.96% of the genetic diversity resulted from differentiation among populations. The coefficient of gene differentiation(Gst)generated by POPGENE32 was 0.222 6. The 6 natural populations of M. chapensis might be divided into 2 groups used UPGMA cluster system,and the genetic diversity of second group was higher than that of the first.
In this paper,chilling injury and quality deterioration of 'Okubao'(Prunus persica (L.)Batsch cv.Okubao)peach fruit under different storage temperature strategies were studied.When stored at 5 ℃,peach fruit showed rapid increase of membrane permeability and juice extraction rate during the first 15 d and lost the ability to ripe during subsequent shelf-life at 20 ℃ for 3 d,which means severe chilling injury.Chilling injury in fruits stored at 0 ℃ occurred at 30 d,but the symptom did not show until the fruit was moved to 20 ℃ for 3 d.Precondition at 24 ℃ for 3 d before storage at 0 ℃ delayed the occurrence of chilling injury,but could not delay fruit softening and thus led to unacceptable quality.When placed at 8 ℃ for 9 d before stored at 0 ℃,membrane permeability and juice extraction were acceptable and maintained its fruit firmness,SSC and pH value,and could ripe and soften normally during shelf-life.The results indicated that cold training at 8 ℃ for 9 d was the best temperature strategy to prevent chilling injury and to keep quality of 'Okubao' peach fruit in 60 d of storage.
The Nutrients changes and the nutrient levels in different canopy layers of 2-year-old Paulownia fortunei Yulinensis in a growing season were studied under the natural condition. The results showed that: ①N concentration decreasesd as a saw shapes in the whole growing season. The highest was 42.0 g·kg-1; the lowest was 21.5 g·kg-1. P concentration decreased in the beginning and extended to be steady from June to October, then, kept the descending trend again. The highest was 2.5 g·kg-1; the lowest was 1.2 g·kg-1. K concentration decreased in the beginning and extended to be steady from June to October, then, kept the descending trend till November, and extended to be steady again. The highest was 14 g·kg-1; the lowest was 6.6 g·kg-1. ②The nutrient content of a whole tree showed descending trend in the beginning and turned to increasing trend till July and decreased till September and increased slowly till the end of the growing season. The highest contents of N,P,and K were 7.26 g·tree-1,0.37 g·tree-1,and 2.3 g·tree-1 which appeared in the end of July;and the lowest was 3.2 g·tree-1,0.16 g·tree-1,and 0.96 g·tree-1 which appeared in September. ③The nutrient content(N,P and K) per leaf kept increasing in the whole season. ④ There was no difference for nutrient element content in different canopy layers.
Based on study materials of 3 biomass research in the similar site condition of Dagangshan forest region and the observed materials of permanent sample plots of Chinese fir, this paper made a relatively detailed study on the change laws of biomass of Chinese fir plantations, and obtained the main results as follows: (1)For the same stands, except that biomass of leaves and some branches have a decreasing duration(from 5 a to 8 a), biomasses of various parts of mean individual and stand all increase with the increasing of stands age, during the quick growth years of stands, the proportions of leaves, branches and stem are weakly increasing, with above ground parts increasing and roots decreasing. In stem growth stage(12～16 a), the proportion of each organ of mean individual tends to be stable. (2)Site indices have obvious affection on the amount of biomass, biomasses of all parts and allocation rate of mean individual and stand, the affection varies with stand age, and is restricted by planting density. (3)With the increasing of planting density, the biomass of each organ of mean individual obviously decreases, the allocation rate of biomass of stem tends to decrease at any age; the discrepancies of biomasses of different stands, caused by planting density, tend to decrease with the increasing of stand age.
Pinus bungeana is a peculiar valuable tree species to China. The character of low growth obstructed its popularity. In this experiment, 7 kinds of ectomycorrhizal preparations were used to treat the rhizosphere soil of P. bungeana seedlings, and the infection ability of ectomycorrhizal preparation and its effect on accelerating the growth of P.bungeana were analyzed. The results were as follows: (1) Mycorrhizal treatment could accelerate effectively the increments of height, basal diameter, dry weight and lateral roots. (2) Mycorrhizal treatment raised the contents of N, P, K and chlorophyll. (3) The excellent fungi strains Boletus edulis and Xerocomus chrysenteron which could accelerate the growh of P. bungeana in Beijing were selected.
Twenty-two months' test in Yuanmou dry-hot valley showed there was high significant increase effect for Azadirachta indica young plantation's fertilization. The most effective treatment was N150P150K50 according to the growth response of N,P and K on young plantation, whose height growth increment was 1.9 times that of non-fertilizer treatment. The growth increment of basal diameter was 2.7 times that of CK. The index of fertilizing effect of these treatments reached 2.86～14.17. The growth of height, and basal diameter of Azadirachta indica young plantation were sensitive to P and N. The result of partial correlation analysis showed there existed positive correlation between young plantation's growth and N,P and K. However, only N and P had significant effect on the growth of Azadirachta indica young plantation.
Three isolates (Bh1, Bh2, Bh3) of Beauveria bassiana separated from Tessaratoma papillosa were studied by comparing the speed of hyphas growths, yield of coniolia, bioassays to T. papillosa, in order to control the insects in the field. The results showed that Bh1 was an excellent isolation to T. papillosa, which could be produced in a large-scale and used to control the insects in the middle and southern of Fujian Province.
Trails on the effects of various nutrition supply conditions on Acer truncatum were conducted. The size of plant, branching pattern and biomass of 2 years old A. truncatum under 9 different treatments were measured and analyzed. The result showed that the different nutrition supply conditions significantly affected the architecture of A. truncatum. This leaded to significant different on growth, biomass and distribution of A. truncatum. Fertilization treatments should be selected by cultivation aims. The treatment N0P250K75 was the best for horticulture tree cultivation with basal diameter of 2.85 cm, height of 1.26 m, crown of 0.59 m2, which were respectively 34.26%、51.66% and 140.23% higher than that of non-fertilizing treatment. The treatment N0P125K37.5 was the best for foliage-usage forest cultivation with total biomass dry weight of 438 g, root biomass dry weight of 192 g, stem and branch biomass dry weight of 159 g, leaf biomass dry weight of 88 g, which were respectively （83.42%）、60.10%、98.13% and 113.44% higher than that of non-fertilizing treatment. Its root/shoot biomass dry weight was （0.81）, which was 18.30% less than that of non-fertilizing treatment.
Taking Shixia watershed as the research object, the vegetation coverage, intensity of soil and water erosion, land use ratio, control degree, the ratio of income per capita and local average were used to calculate the evaluation index value by fuzzy comprehensive evaluation method. Base on the standards established according to critical value of sustainable development index, some conclusions were got. The results showed that Shixia watershed belonged to unsustainable development stage in 1991 and sustainable development stage in 1999.
Making use of the methods of multi-scale ordination(Ver Hoef Glenn-Lewin,1989),the pattern intense and pattern consistence index(Dale Zbigniewicz)and the moving weight average quadrat scores(Noy-Meir Anderson),the paper analyzed the vegetation pattern characters of the natural Nitraria tangutorum communities in half fixed dunes outside the Huanghe River irrigating oasis and the well water irrigating oasis including pattern scale,species combination at different scale,behavior of the vegetation along the transect,pattern intense and pattern consistence.The results showed that both the two half fixed Nitraria tanguiorum communities were shrub patterns controlled by single species.The association of same species were different at different scale and under different environment condition.The average number of pattern scale was more,pattern scale was larger,the corresponding pattern intense was lower,and the pattern consistence was smaller in Nitraria tangutorum communities of half fixed dunes outside the Huanghe River irrigating oasis,contrasting with that outside the well water irrigating oasis.
The paper dealed with the absorbtion and accumulation P nourishmet in mycorrhiza of Dendrobium candidum.The results showed that the effect of P with different origin to the seedling growth was different. The dry weights of treatment 3（ KH2PO4） and treatment 6（ FePO4） were 0.018 and 0.019 g respectively, which were 2.62 and 2.78 times than that of treatment 1. The difference was significant. The effect of different concentration of dissoluble P（KH2PO4） to the mycorrhiza tissue culture seedling of Dendrobium candidum, primarily expressed in seedling height, stem and dry weight etc. Treatment 3 was the most suitable and proper density was 0.25 g· L-1. Compared with treatment 9（CONTROL）, the seedling height, stem and dry weight of treatment 3 were 2.64, 2.16 and 3.87 times respectively. Through the analysis to the N, C, P nutrient absorption and accumulation, treatment 3 was 1.72, 1.40 and 11.53 times than that of CONTROL. The result of test on the effect of different available P to propagational growth of Dendrobium candidum mycorrhiza fungi F9903 showed that, when the culture solution contained 1 mg of P content was 22.76% in KH2PO4, the effect of mycelium multiplication was the best, the dry weight was up to 1.256 mg·mL-1,114.2 times that of its inoculum size. In the pillar type diagram of the dry weight of the symbiosis mycorrhiza fungi hypha and the tissue culture seedling with mycorrhiza of Dendrobium candidum in the different density of P nourishment, the shape of diagram and the trend were similar.
Individual variation of gutta-percha content in barks of Eucommia ulmoides and the correlations between gutta-percha content character in bark and several macroscopic properties were systematically studied by means of selecting the typical plants and random sampling. The result showed that the differences of DBH (diameter at breast height), the bark thickness and gutta-percha content in bark were in significant level among various clones. The gutta-percha content rate among different Eucommia clones had a significant negative relation with the phellem thickness and the ratio of phellem to bark thickness and it also negatively related to DBH, which indicated that larger DBH and thicker phellem led to less gutta-percha accumulations. Gutta-percha content in unit volume of bark related positively significantly with gutta-percha content rate in bark and volume weight of the bark.
Experiments of using Baktop capsules to control termite were made in Yuhang of Zhejiang Province from 1997 to 2003. The contact poisoning effects of 5 different dosages(62.5,125,250,500,1 000 mg·kg-1) were all 100%,and the mortality of the least dosage,62.5 mg·kg-1,was also 100% after 3 days. The expellable effect and the wood resistance to termite were very excellent though termite could pass through a short distance in the poisonous soil treated by the least dosage,62.5 mg·kg-1. The results of field soil treatment test showed that control effect of the poisonous soil treated by 250～1 000 mg·kg-1 Baktop to termite was positively correlated with the dosages of pesticide.The control effect of 1 000 mg·kg-1 was 100% after 5 years,and 80% after 6 years.The results also showed that efflorescence had no effect on the control effect of Baktop.The control effect of Baktop capsules to Reticulitermes speratus was better than that of to Coptotermes formosanus.
The growth curves of MZ rhizobium and 217 phosphobacteria were drawn in four media in this study. The results showed that these two strains could both grow well in BSE medium. Based on the conventional media, the optimized media of MZ rhizobia and 217 phosphobacteria were obtained from orthogonal tests. Furthermore, the optimized media were testified to be more suitable for the growth of both of the strains, with more live bacteria, by the growth curves got afterwards. The tight relationship between pH level, phosphate-dissolving and bacterial growth ability was also discussed in the study on the phosphate-dissolving ability.
The effect of the supplement of antibiotics on induction and growth of camellia callus was studied. Kannamycin and Hygromycin were more sensitive to growth of callus of C.chekiangoleosa than that of C.magniflora. Growth of callus would be limited by Kannamycin at 50～60 mg·L-1 and Hygromycin at 25～30 mg·L-1. The leaves of C.grijsii seeding could not induced callus when Kannamycin and Hygromycin arrived the same concentration. Carbenicillin could accelerate induction of callus at certain degree but didnot affect the growth of callus. Amoxicillin inhibited slightly the growth of callus. Cefotaximes reduced both the ratio. According to the effect of inhibiting Agrobacterium tumefaciens, concertration of Carbenicillin and Amoxicillin were 250 mg·L-1 and 125 mg·L-1 respectively in the study of transformation.
Seven species of wild perennial plants were chosen as experimental materials, the salt resistance of these plants were studied. The salt matrix include NaCl and Na2SO4, the salt content is 0, 2.5 g·kg-1,5 g·kg-1 and 10 g·kg-1.The results showed that all the plants could not germinate with the salt of 10 g·kg-1.All these plants could germinate and grow in the saline soil with the salt content of 2.5 g·kg-1.In this treatment the most rate of germination was Viola prionantha（46.35% more than that of control）. When the salt content is 5 g·kg-1, only Iris lacteal, Taraxacum mongolicum,and Coronilla varia could germinate and grow,but the germination delayed, and the rate of germination decrease markedly. The salt treatment made the proline increased markedly,but less effect on soluble sugar when treated as 2.5 g·kg-1 or 5 g·kg-1. When the plants were treated as 5 g·kg-1, the content of MDA increased markedly.It suggested that it was seriously harmful to plants as salt content 5 g·kg-1.
The difference of chemical composition among five acacia species woods (Acacia auriculaeformis, A. crassicarpa, A. cincinnata, A. mangium and A.melanoxylon ) were compared. The ash, holocellulose, α-cellulose, 1%NaOH extractive, benzene-ethanol extractive, pentosan,lignin and relative crystallinity contents were investigated. By this study, the chemical composition variable disciplinarians among the five acacia species woods were found. The results showed that they had almost the same chemical properties for A. auriculaeformis, A. crassicarpa and Acacia mangium; the chemical composition of A. crassicarpa had significant differences with that of A. cincinnata and A. melanoxylon, while the chemical composition between Acacia magnium and A. cincinnata as well as between A. cincinnata and A. melanoxylon also had remarkable difference. The contents of holocellulose for the woods (Acacia auriculaeformis, A. crassicarpa, A. cincinnata, A. mangium and A.melanoxylon) were 71.25%, 70.84%, 75.47%, 72.38% and 71.77% respectively;the contents of α-cellulose:45.30%, 46.47%, (50.15%), 46.48% and 43.99%;the contents of lignin:22.83%, 24.12%, 18.54%, 21.98% and 20.77%; the contents of relative crystallinity:58.74%, 43.36%, 43.42%, 39.74% and 41.89%;the contents of 1%NaOH extractive:22.02%, (21.20%), 22.73%, 22.00% and 26.20%;the contents of pentosan:22.98%, (21.20%), 24.68%, 23.20% and 24.72%;the contents of benzene-ethanol extractive:5.78%, 5.38%, 6.13%, 6.20% and 6.25%。
One thousand and fifty eight species of medical plants belonging to 471 genera and 132 families were found in Baotianman,Henan Province. Of which 15 families such as Rosaceae, Compositae, Liliaceae, Ranunculaceae, etc. occupied 38 % of the total, 18 genera including Artemisia, Polygonum, etc. made up 20.6%. The plants using rhizomes as medical materials accounted for 28.6% of the total, the ratio of the species living in forests was 43.8% of the total. The results showed that the richness of Chinese medical plant resources was high in this area, forests were the resource pool of medical plants. To protect and utilize the medical plants properly, four aspects should be emphasized:(1) Law-making and law-executing should be strengthened about the collection, utilization and commerce of the wild biological resources. (2) Science research about medical plants should be strengthened.(3) Arboretum of medical plants should be built.(4) Breeding bases about the high value medical plants should be established.
The tolerance of three pathogens (Pseudomonas sp.,Xanthomonas sp. and Erwinia sp.) to temperature and pH value was studied. The pathogens could induce 'Dongzao' jujube fruit decay. The results showed that the tolerance of Pseudomonas sp. to low and high temperature was 0 ℃ and 57.5 ℃, Xanthomonas sp.'s was -2 ℃ and 55 ℃, Erwinia sp.'s was 0 ℃ and 57.5 ℃. The tolerance of the three pathogens to alkalescence was more resistant, Pseudomonas sp. could not growth until pH value was 10, Xanthomonas sp. and Erwinia sp. could still growth normally when pH value was 12; at the range of acidity, when pH value was 2～4, the growth of three pathogens were inhibited. In the combination test of pH, temperature and time, when pH value range was 3～4, the treatment time was 6～8 min, the temperatures of Pseudomonas sp.,Xanthomonas sp. and Erwinia sp. were 45 ℃, 55 ℃ and 50 ℃ respectively, their growth were inhabited obviously.
Comparison research trial was conducted on Schleichera oleosa as lac host, including technology of seeding,afforestation, branch utilization and biological characteristics of Kerria lacca. The results showed that seed germination rate could be increased with the way getting rid of the capsule. Seedlings were raised in March and plant at the beginning of monsoon( It is about June and the first ten days of July in Yunnan province). The land suitable for the tree should be deep and loose soil and right drainage condition such as mid and low area of hillside. Afforestation effect could be better if the tree was planted at the south side of the hill. Young sapling could grow better with scarification and weeding and fertilizer superaddition. Schleichera oleosa was the best host tree for Kerria lacca and the output of lac was stable at winter and summer generations. It was also a favorable tree species for both keeping brood lac and for producing lac and it could be utilized by Kerria lacca once a year.
Based on the research of red soil sample that developed from granite, the results are as follows: （1） Because the content of NO3-N in soil, especially the top soil, is infected seriously by the precipitation, soil sample should be collected on the day that avoid special weather such as rain. It is better to collect on the day without raining for 3 to 5 days or 1 week after rainstorm; （2） Three keeping ways of soil sample are taken in the test, that were wind drying, cooling and freezing. Error analysis showed that the average relative error of wind drying, cooling and freezing way were -8.16%, -5.18% and 0.185% respectively. The best keeping way is freezing（in temperature of -6～-7 ℃）. （3） Through three group contrastive experiments,it was found that the best vibrating time of sample testing was 30 minutes.
The poplar canker has been an important biological disaster of poplar plantation in China, and is becoming more serious than ever before. From the viewpoints of plant histopathology, physiological pathology and pathological chemistry, this paper reviewed and summed up the achievements obtained and problems existed in the study on the interaction of poplar and canker pathogen. The authors also made some discussion on the future research in this field.
Landscape fragmentation is one of the major reasons which lead to the drastic degression or loss of biodiversity over the world.It blocked gene flow among populations, caused inbreeding depression; and altered bio-geographical environments the species depended on, and minished the living space of the species. On the other hand, fragmentation transformed the traits of ecosystems, affected energy balance and matter flow,and attracted invasion of extra-species. The paper described the above mentioned aspects in order to better understand the profound effects of landscape fragmentation on biodiversity.The issues or hot spots of future study in this field, as well as conservation approaches, were also discussed.
Total contents and components of escin were studied in seeds of Aesculus chinensis, A. chinensis var. chekiangensis and A. wilsonii collected from 8 origins. Results showed that total escin content ranged from 71.43 mg·g to 112.69 mg·g,with the highest in origin of Mabian, Sichuan Province and the lowest in origin of Kangxian, Gansu Province. It was suggested that escin content was correlated with geological zone to a certain extent. A.wilsonii was richer than that of Aesculus chinensis in escin content.The proportion of 4 types of escin varied dramatically among different origins. Component A in Mabian and Cangwang origin from Sichuan Province, Kangxian origin from Gansu Province, Mianxian origin from Shanxi Province and Xixia origin from Henan Province reached 35%～41% of total escin that was much higher than that of other components, while components D was below 15% that was only 1/3 of component A. Sum of Component A and C was nearly equal in Enshi, Hubei Province and Sangzhi, Hunan Province origins, which accounted for 58% of the total content. Lin'an origins from Zhejiang Province only got (17.17%) of component A while holding much higher proportion of component D. Statistical analysis also approved that the proportion of escin was correlated to geological zone.