1998 Vol. 11, No. 4
The responses of A.cacia melanoxylon,A. meamsii,A. implexa, A. dealbata to rhizobial inoculation were reported in this paper. The results showed that the height,total biomass and nodule biomass of inoculation of Acacia with different rhizobium strains were 1.353 8～2.602 6,1.178 5～3.357 9 and 0.022 4～1.026 1 times higher than those of the controls;the height ,total biomass and nodule biomass of inoculation of different Acacia species/provenances with the same sets of rhizobium strains were 0.026 4～1.098 2, 0.018 2～2.814 8 and 0.647 0～2.111 5 times higher than those of the controls. The N concentration and total nitrogen of inoculated seedlings were 0.085 8～0.775 5 and 0.116 4～2.625 0 times higher than those of the controls. Most of the fixed nitrogen by nodules were transported and stored in aboveground than in underground plant parts.A correlation existed between the fixed nitrogen and the height of seedlings.
A technique for mass proliferating mini shoot scions in vitro of the prcocious walnut cultivars (Juglans regia) has been established. Tests on the proliferation were carried out and presented in this paper.The results showed that it was the suitable time to collect the shoot node explants in tree for in vitro culture when the shoots grew to form 8～10 nodes. The shoot tip and the fourth and fifth nodes under the shoot tip in the shoot had highest survival and germination rate after being sterilized and cultured in vitro. The proliferation rate and the quality of mini shoot scion was obviously influenced by th BA level in DKW medium,the temperature for culture and the proliferation subculture interval,and the best results were achieved when BA in the medium was 0.5～1.0 mg/L,changing temperature of 25±3 ℃ in day and 18±2 ℃ at night and 20 d interval of proliferation subculture.The treatment of cutting off the shoot tips (about 0.5 cm) of the deteriorated shoots clump could partly recover its growth vigor and inhibited its flowering in vitro.From our tests, a modified DKW medium was developed which could dismiss the deterioration phenomenon.After being applied in our lab,the modified DKW demonstrated a better medium for mass proliferation of the mini shoot scion of precocious walnut cultivars.
The seed oil of Camellia grijsii (GRI) and C.oleifera (OLF), olive oil (OLV) and olein (OLN) after enzymolisis etc.were added to MEM medium to culture the human diploid foetal lung fibroblasts(2BS). The results showed the similar antisenile effects of the seed oil of C.grijsii and olive oil. Significant lower accumulation of LPO in cell membrane tested at 46th generation of the above two groups than that of OLF,unsaponifiable fraction of GRI(NSG),OLN+NSG and OLN groups were found. The lifespan of cells in GRI and OLV groups wast 2 generations longer than that in OLF group. The comparison of morphology of 2BS under microscope revealed the same sequence as the result of LPO testing and lifespan observation. Preliminary conclusion is that an appropriate existence of linoleic acid is essential to prolong the lifespan of 2BS with the main component of oleic acid in certain edible oils,and there are some active components in unsaponifiable fraction of GRI which could delay the aging process of 2BS.
A progeny test trial with 31 families of Casuarina junghuhniana was established at Yangxi of Guangdong. After planting,tree heights were measured for 6 times and DBH was for 5 times. Based on 12 quantity or quality traits of the 31 families,analysis of variance,covariance,correlation,variance component were carried out to estimate genetic variation coefficient (Gcv),family heritability(hf2),early-late correlation of tree height(H) and DBH ,phenotypic and genetic correlation and genetic gain. Results showed that there are significant correlation in heights from the 5 months to 5 years and DBH from 1 year to 5 years after planting. There were significant differences in 12 trait values between families. Genetic variation coefficients of tree height, DBH,single tree volume(V),pole height(Hs) and crown width(Cm) were respectively 35.56%、33.44%、93.02%、30.91% and 22.53%,other trait values were 3.95%～16.02%. Analysed the phenotypic and genetic correlation of 13 trait values. Calculated the heritablities for 12 traits,except survival percentage heritability was 0.55,the other 11 traits of heritabilites were 0.80～0.94. When selection portorption was 20%,genetic gains of main growth traits in H,DBH and V were respectively 24.03%,22.38% and 60.90%,and genetic gains of main quality traits in stem straightness,permanent branch density,survival percentage,stem persistence and tree health level were 6.85%～15.17%. Finally,using breeding values and selection indexes,evaluating the 31 families of performance and found out some dominant families.
Quantitative survey and research on barnacle species attaching to mangroves,the relationship between barnacle quantity and biological and ecological factors,barnacles harm to artificial young mangrove trees and their chemical control was conducted.The results showed:there existed two barnacle species on artificial young mangrove trees,namely Balanus reticulatus and Chthamalus sinensis.The barnacles quantity attaching to mangroves had positive correlation with their habitat seawater salinity,tide inundating depth and tide flooding ratio. On the other hand,the decortication of trunk of some mangrove trees such as Kandelia candel,Sonneratia caseolaris and other marine algae’s attaching to mangrove tree trunk decreased barnacles’ quantities to some degree.Large scale of barnacles attaching to young mangrove trees (1～3 a) reduced the increment of tree height and trunk diameter,caused tree trunk in deformation and even death. Low toxic chemicals blended with red paint(1:1 000～2 000) was smeared on young mangrove tree trunks to which barnacles attached,the control effect was up to 100 percent;whereas low toxic chemicals diluted in water was sprayed on the trunks,branches and leaves of young mangrove trees,the control effect was not obvious.
Four strains GW-1,GW-5,GW-10 and GW-16 isolated from Phyllostachys pubescens roots are identified and studied. According to the research on morphology,physiological and biochemical character,these strains all belong to Bacillus polymyxa. Their optimum temperature for nitrogen fixing is 30～35 ℃ for GW-1,30 ℃ for GW-5 and GW-16,35 ℃ for GW-10. Optimum pH for nitrogen fixing is 7.5 for GW-1 and GW-10,7.0 for GW-5,6.0～7.5 for GW-16. Many carbon sources can be used by these four strains,but the highest nitrogenase activity can be obtained when the carbon sources is the mixture of glucose,sucrose and malic acid. Under different culture time condition the highest nitrogenase activity is 156.90,89.37 nmol (C2H4)·h-1 ·bottle -1 for GW-1 and GW-5 in 96 h,56.63,83.64 nmol (C2H4)·h-1 ·bottle -1 for GW-10 and GW-16 in 72 h.
Two kinds of lac insect (Kerria chinensis,K.lacca) were radiated in this radiation experiment. The different stage of lac insect (larva,adult) are radiated by several dosages of Co 60. Tests showed that lac insects in the second stage are all dead after radiation of 500～2 000 rad,female insect of K.chinensis with pregnancy egg time 2～3 stage radiated by 1000 rad can produce new generation. female insect of K. lacca with pregnancy egg time 5～6 stage radiated by 11 000 rad occasionally produce new generation. The egg amount and amount of secreting lac are similar to those of the normal,effective production and sex ratio are higher than those of the normal,group density on branch is lower than the normal in the generation of K. lacca after radiation. The sex ratio of the female,group density on branch are higher than those of the normal,egg amount and amount of secreting lac are normal in the generation of K.chinensis after radiation.
This article deals with the correlation among the occurrence period of Dendrolimus superans (Butler),phenology and 24 solar terms as well as its occurrence amount,warm rain coefficient in May and overwintering larva′s shit in Yakeshi forest destrict from 1993 to 1995. We set up the regressive estimate model of the volume of occurrence (y):ŷ =196.268 0-23.517 0x1,ŷ(larva)=2.449 9+0.073 2x2,ŷ(adult)=11.970 0+0.027 8x2,in which the warm rain coefficient and larva′s shit act as dependent variable. The reasearch proves that it makes a great differencc to the height,the chest diameter and the volume of tree when loss amounts of Larix gmelinii leaves go beyond 45 percent in the total. Before the middle of May,the numbers of the trees which have insects is over 40 percent of the total trees,and the mature larvae adult insect density in each tree is over 50 heads and the young larvae density is over 101 heads,control measure should be adopted.
Pine caterpillars are the most destructive forest pests in China. A very important aspect,that is, the traditional knowledge of these insects from ethnic communities in the mountain regions,especially in Yunnan,has long been ignored in studying them. Working in these areas, we found that many indigenous groups such as Hani,Dai and Lafu minor nationalities favor eating the pupae of pine caterpillars and this phenomenon is very popular in some areas. According to our investigation,this practice is related to poverty in history;the first ethnic group using the pupae as food might be the Kaduo,a branch of Hani,in Mojing;and this tradition dated back from as early as late Qing Dynasty or before. This traditional knowledge shows us that these pests could be turned into resources and controlled through exploiting and utilizing them.
In 1995,the community characteristics of the ever-green broad-leaved second growth and the Chinese fir plantation were investigated in Damaoshan Mountain,Jiangxi Province. Their biodiversity difference were studied and their forest growth condition and the amount of above-ground biomass compared. The results show there are distince differences of community characteristics between them,and the biodiversity indices (Simpson diversity index,species richness of community,community evenness) of the second growth are higher than those of the plantation,under the same site conditions stock and growth in unit area of the second growth are lower than those of the plantation,but above ground biomass of the second growth is higher. All these results proved that the closing of forest area played a positive role in protecting biosources and biodiversity.
In this paper,the methods of breaking the seed dormancy and stimulating the seed germination for Cercis chinensis were studied. The results showed that the seed dormancy of this species could be broken through corrosion with high concentrated H2SO4 for 30 min and then with stratification in 13～17 ℃ for 20～30 d. The optimal germination results were obtained through culturing the seeds in darkness under 20 ℃ at night and 30 ℃ in daytime.The germination rate,the survival rate of seedlings,the germination index,the vitality index and the average total length of stem and root per individual were respectively 82%,80%,9.41,73.78 and 7.92 cm under these conditions,and those were respectively 90%,83%,9.09,71.0 and 8.81 cm if the seeds were soaked in solution of gibberellin for 24 h.
During the adult′s replenishing nutrient period, chemical control is the effective way of cotrolling the population of Monochamus alternatus by spraying pesticides.After three different spraying treatment of mixing fenthion, polyvinyl alcohol (PA) and deltamethrin,and at the same time,feeding treated twigs in laboratory as auxilizary means.As result,chosed the best type of pesticides:fenthion(12%):PA(9711)(40%):deltamethrin (12%) diluting 150:10:2000,can remain at least 20 days′ extended controlling, and reduce ratio of death of Pinus massoniana at 100%,twigs′ 96.4%. Methamidophos (50%) 1:3 as the efficient type for ejecting pesticides into trunk at 0.5 m height from ground,but dense adult population can cause much more flunctuation. PA(9711) can sustain longer extended controlling period than BA 154 as adeherent substances,respectively,with 50% fenthion on Pinus massoniana and feeding the adults with these treated branches in laboratory,and PA(9711) attributes to extend fenthion 28 days′ ability,so it can use as the optimum auxiliary solvent,but BA 154 became resistant to fenthion.
The results of study on the 10 a loblolly pine provenance test in Fuyang City of Zhejiang Province showed that the distinct differences in main traits relating to the provenance evaluation of construction timber existed among provenances in juvenile wood stage,the phenotypic variation coefficients of growth traits were 10%～30%,of traits of wood physic-mechanical properties and tracheid morphological features were about 5%,all of these traits were genetically controlled with above moderate broad sense heritabilities,the simple phenotypic correlations between growth traits and wood property traits were weak. The results of multitrait selection using preliminary index showed provenances of RL31,RL26,RL30,RL22,CL8 were good for construction timber,their average genetic gains of stem volume,wood density,crushing strength,modulus of elasticity were 5.96%,5.44%,3.17%,4.87% respectively compared with the average value of the test stand.
Losing a certain number of one-year-old needles will have a significant effect on the height growth of Pinus tabulaeformis and the length of needles in the following year:the greater the loss,the more serious the effect. After two years,they will return to the normal status although still be different in height growth. If the losing is a small number of two-to-three-year-old needle,the pines have compensation and super-compensation effect,but if one-year-old needle,they have not. In the years when the pine caterpillar burst out and 95% of the one-to-two-year-old needles are lost,the pines will return to normal status in three years if the site situations are good and they will not if the site situations are poor,for example,a dry southern slope. So,in the control of pine caterpillar,making the widest possibility to reduce the loss of one-year-old needles is a key to ensure the normal growth of pine trees.
The application of molecular markers to related studies of forest trees has great merits to those fields that include construction of genetic linkage map,comparative genome mapping,QTL detecting, marker-assisted selection (MAS),phyolgeny as well as population variation and bio-diversity. Up to now,there were about 20 tree species which have been genetically mapped with molecular marker method,in which comparative studies of genomes have been carried out on several species. More than ten QTLs have been detected and MAS is ongoing on a few species. Molecular marker technology is also an important tool for estimating population genetic structure and diversity level,and identifying phylogenetic process and relatedness for a certain taxon of forest tree.
Study on two spacing trials of short-rotation Eucalyptus urophylla showed that: (1) The more the planting density,the bigger the stand volume;the planting density may be increased to 2 500～3 000 trees/ha instead of 1 667 trees/ha which is the popular spacing in forest practice. (2) The more the planting density,the stronger the storm-resistance in 5 spacings of the trial. (3) Planting density has no remarkable effect on wood fibre length,width and basic density.
The differentiation of flower bud and development of male gametophyte in Calycanthus chinensis have been studied. The flower bud differentiates in centropetally and multiserial archesporial cells are formed at the hypodermal position of anther. The microspore tetrads are arranged in tetrahedral pattern. In about 7～8 layer cells of the anther wall developed in dictyledonous type,multinucleate tapetum,which may divide transversally or obliguely,get to degenerate when the microspore mother cells undergo meiosis,and remain in a parietal position until these cells are absorbed completely by the pollen grains. So it belongs to secretory type. However,2 of middle layers are still remain. As the pollen grains are shed,they are at 2 cell stage.
Suillus luteus (L.ex Fr.) is a superior mycorrhiza fungi being symbiosis with Pinus massoniana in the subtropical area of China. The fungi is widely distributed and has been effectively applied to the pine. In order to examine the liquid cultural conditions of the S. luteus, the temperature,pH,carbon sources,nitrogen sources and C/N for the growth and the propagation of the fungi were tested in the study. The results showed that for the growth and propagation of the hyphae of the strain S.l, the suitable temperature range was 20～30 ℃, the optimum 25 ℃;the suitable pH was 3～8,the optimum 4～4.5. All the carbon sources tested can be absorbed (glucose,fructose,saccharose,amylomaltose,ethanol,mannitol, soluble starch,dextrin) but the optimum was soluble starch;all the nitrogen sources [(NH4)2SO4,(NH4)2HPO4,NH4NO3,KNO3,Urea,tartaric acid,aminoacetic acid,glutamic acid],except inorganic nitrogen (KNO3),can be absorbed but the optimum was glutamic acid. A wider range of C/N was effective but the optimum was 20:1.
Seven exotic poplar clones were introduced to Minhou County,Fuzhou City from Australia and Pakistan. Cultivation trial have been conducted on sandy riparian site of Minjian River and along the road sides for six years. On the sandy riparian site of Minjiang River,the height and DBH of the deciduous poplar clones S7C3,S7C20,ST92 and Y706 exceed and are close to that of control clone Populus×euramericana cv."San Martino" I 72/58.The average height is 11.2 m and the average DBH 16.1 cm for the five year old control clone.Three semi-evergreen poplar clones A-65/27,A-65/31 and A-61/186 can not endure frequent and prolonged floods and have a lower growth rate. However,they are suitable for road side planting. The average height is 20.0 m and 15.8 m and the average DBH is 25.5 cm and 29.4 cm correspondingly for six year old semi evergreen poplar clones A-65/27 and A-61/186. Seven introduced polar clones are promising fastgrowing deciduous tree species for Fuzhou area.The performance of the three semi evergreen poplar clones is different from that in Australia,they keep green leaves on trees all the year round in Fuzhou area,like evergreen tree species. On sandy riparian site of Minjiang River,the growth rates of S7C3 and S7C20 obviously exceed that of control clone and other clones.
The effects of applying P fertilizer on nutrition and P fraction in yellow-red soil of young Chinese-fir plantation were studied in Jiangxi Province in 1991～1994. Fertilization increased the contents of organic matter,total N and P,available N and P,Fe-P and O-P in soil. Compared with the control,the contents of organic matter,total N and available N were increased by 43%,27% and 32% in treatment 5 (N100P100/ha) and 6 (N100P100K100 /ha),total P and available P were increased by 70% and 356% in treatment 5,respectively. The increased Fe-P (except for treatment 1) and O-P (except for treatment 3) ranged 2.5～13.9 mg/kg and 6～73 mg/kg,respectively. Ca-P in soil was reduced by 0.3～9.0 mg/kg in fertilized plots. There were different changes in organic P in various fertlized plots. Organic P was reduced by 87～128 mg/kg in treatment 2,5 and 6 while it was increased by 21～97 mg/kg in treatment 1,3 and 4. Compared with the control,there was no significance in the effects of fertilization on pH value and Al-P in soils.