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1.
Control of Lymantria dispar L. by biological agents   总被引:1,自引:0,他引:1  
The experiment on control ofLymantria dispar L by using different kinds of biological measures, including nuclear polyhedrosis virus (NPV) ofLymantria dispar L., BtMP-342, sex-attractant as well as botanical insecticide, was carried out in the forest regions of Inner Mongolia in 2003. Two concentrations (2.632×106 PIB·ml−1 and 2.632×107 PIB·ml−1) ofLymantria dispar L. NPV were sprayed on the 2rd-instar-larvae ofL. dispar and 70% and 77.8% control effect were obtained respectively. BtMP0-342 was applied to the 3rd- and 4th-instar larvae and the control effect was around 80%. The sex-attractant provided by Canada Pacific Forestry Research Center also showed a good result in trappingL. dispar adults. The self-produced botanical insecticide, which was extracted from a kind of poisonous plant distributed in Daxing'an Mountains, China, exhibited a good control result in controlling the larvae ofL. dispar, and 82% mortality was observed when spraying primary liquid of the botanical insecticide on the 3rd–5th-instar-larvae in lab. Foundation item: This paper was supported by Natural Science Foundation of Heilongjiang Province (C0235) and Youth Foundation of Harbin City (0061218024). Biography: ZHANG Guo-cai (1964), male, Ph. Doctor Candidate, associate professor in School of Forestry, Northeast Forestry University, Harbin 150040, P. R. China. Responsible editor: Song Funan  相似文献   

2.
Female Plant Types of Ginkgo biloba L. in China   总被引:1,自引:0,他引:1  
Ginkgo biloba is a dioecious and unique species within Ginkgo family and Ginkgo genus, but it shows a big variability. From 1950s, resources of female plants in China were investigated and collected, and the seed anatomical structure and morphological characters at different development stages were observed. According to the shape, length, width and thickness of ovule bracket and seed stone, as well as the characteristics of both sides and top of the stone, the female plants of Ginkgo biloba have been divided into five types, long-stone, Buddha-finger, horse-bell, mume-stone and round-stone. In addition, the important cultivars belonging to different types were also determined. The stone weight, index of stone shape, and contents of dry matter, amylose,amylopectin, starch, rough protein, soluble sugar and hydrocyanic acid in seed kernel of each type were measured, and the qualities of seed stone were appraised, which lays a foundation for the improvement and utilization of female plant resources in Ginkgo biloba.  相似文献   

3.
The term allelopathy refers to biochemical interaction between all types of plants including microorganisms through pro-duction of chemical compounds that escape into the environment and exist widely in Quercus L. The development of investigations into types of allelochemicals, their compounding and spreading pathways, as well as expression of allelopathy in Quercus L. are re-viewed in this paper. We have closely and systematically emphasized the functional mechanisms of allelopathy in forest plants for our next research project on allelopathy in Quercus L.  相似文献   

4.
During three consecutive years, 1978–1980, cloudberries (Rubus chamaemorus L.), cranberries (Vaccinium oxycoccus L. & Vaccinium microcarpum Turcz.) and lingonberries Vaccinium vitis‐idaea L.) growing wild in Swedish forests and mires were inventoried in the annual National Forest Survey. Both the coverage and fertility of these were estimated. Observations from 42 000 test sites (314 m2 each) were processed according to geographical region, composition of tree and field layer, altitude and occurrence of draining ditches. Cloudberries cover 425 000 hectares or 1.5 % of the total investigated area (28.6 million hectares). The corresponding values for cranberries and lingonberries are 136000 hectares (0.5 %) and 1362000 ha (4.8%) respectively. Open mires have a greater degree of coverage by cloudberry and cranberry than wet forests on peat. The reverse situation is true for lingonberry. The total berry yield on peatland was estimated to 116.6 million kg (freshweight), distributed as 75.7 million kg cloudberries, 20.8 million kg cranberries and 20.1 million kg lingonberries. The corresponding production of lingonberries on mineral soils was 188.8 million kg. Both in wet forests and on mires, drained areas show lower berry production for the three species, with one exception. Lingonberries yielded better on drained mires. Productive stands of cloudberries and cranberries ought not to be drained for economic reasons.  相似文献   

5.
Defence proteins are a kind of chemical defence compounds. They play a key role in plant restraining biotic and abiotic harm. To illuminate activities of some defense proteins associated with age or plant family of larch, the larch needles were collected from two different families of Korean larch, Larix olgensis and a hybrid larch, L.kaempferi × L. gmelinii, respectively, and then the activities of defence proteins in those were tested using a UV spectrophotometry. The results showed that the activities of protective enzymes at the16-/17- and 19-year-age groups were higher than those at the other age groups in the both larch species. While the activities of polyphenol oxidase(PPO) at the 16-/17-year-age group and phenylalanine ammonia-lyase(PAL) and protease inhibitors at the 19-year-age group were the highest among all age groups.Then, compared with L. olgensis, the hybrid larch had significant effects on the activities of protective enzymes.The effects of plant family on the activities of PAL and chymotrypsin inhibitor were significantly different, and then those on the activities of PPO were not significantly different. The effects of the two families in L. olgensis on the activities of trypsin inhibitor(TI) were significantlydifferent, while those in the hybrid larch on the activities of TI were contrary. To conclusions showed that the different age and plant family significantly affected the activities of defence proteins in the needles of two larch species, and then enhanced the larch resistance to pests. These could play a key function in forestry tree genetic improvement and management in future.  相似文献   

6.
如今,在西方国家正流行一种R.E.A.L饮食,它适应于那些忙碌人们的营养需要,不仅让人满足、使人快乐,激励大脑,而且还让身体保持健康。R是常规饮食在固定的时间里吃营养平衡的食物可以阻止血糖降低。大脑需要葡萄糖和氧气的按时供应,所以按时  相似文献   

7.
Plant flowering and breeding characteristics are important for us to understand the reproduction of plant populations. In this paper, we studied the reproduction characteristics of Jatropha curcas in Yuanjiang County (23°36′N, 101°00′E), Yunnan Province. The plant produces flowers in dichasial inflorescences. Normally, the flowers are unisexual, and male and female flowers are produced in the same inflorescence. Only a few male flowers are produced in an inflorescence, and fruits are produced only through pollination between different flowers from the same or different plants. By the treatments of emasculation, bagging and artificial pollination in this experiment, there were few but same fruit set ratios when the inflorescences were emasculated, bagged, or bagged with net, except artificial pollination treatments, which showed that Jatropha curcas could produce fruit through apomixis but not wind pollination. When the inflorescences were unbagged, unemasculated and with free pollination treatments, or bagged, emascu- lated and with artificial cross-pollination treatments, or unbagged, emasculated and with free pollination treatments, there were many fruits produced. It showed that Jatropha curcas shows outcrossing, is self-compatible, and demanding for pollinators. Normally, the male flowers open first and a few flowers bloom in one day in a raceme. These flowers last a long time in bloom. However, a large number of female flowers open from the third to the fifth day, with some female flowers opening first in a few raceme. This shows a tendency to promote xenogamy and minimize geitonogamy.  相似文献   

8.
1INTRODUCTIONElaeagnusangusifoliaLisahighlytolerantnativewoodyspeciesinsouthernEuropeandAsia.Itmaybeusedinreforestationandsoil-waterconservationandforanexcellentwindbreaktoarrestwind(Bertrand,1985;LiShaozhong,etal,1997),materialsoffragranceandmedicineandnutritivefood(ChangZhaofeng,etal,1994;Goncharova,1997;Rasekh,1999;Ahmadiani2001;JiangFashou,etal,2002).Insomepreviousresearches,BA,2ip,KN(Bertrand,1985,Economou,1988)andBA(Iriondo1995;Mariella,1996)wereusedinshootmultiplicationofE…  相似文献   

9.
SeveralcontentswithintheprovenancetrialandpopularizationprojectofPinusmassonianaL.inGuangxihavebeenincludedinthenational6th5-yearplan,7th5-yearplan,8th5-yearplanand9th5-yearplanscientificandtechnologicalprograms.Ithasobtainedagreatachievementthroughtheeffortofmorethan20years.Evaluatingtheeconomicperformanceoftheprojectnow,anddothenewquestintakingthegaugeofmethod,inordertogetteach-inwithcolleaguesandexperts.1PINUSMASSONIANAL.POSITIONINTHEECONOMICDEVELOPMENTINGUANGXIChina…  相似文献   

10.
冯养正  LI Yi  LIAO Zhao-jun 《沙棘》2006,19(1):33-35
Total flavones ofHippophae rhamnoidesL.(TFH)is clinically usedtotreat angina pectoris,alsohas antiarrhythmic effect[1,2]Our former study showsthat total flavones ofHippophae rhamnoidesL.(TFH)canincrease the cadiac function of rats.Thisstudy observed the effects of TFH on the cardiacfunction and hemodynamics of normal subjects.1Materials and Methods1.1DrugsTFHwas manufactured by Hua Xi pharmaceuti-cal factory.Placebo contained starch.1.2InstrumentsRM-6000,8-channel physiological recor…  相似文献   

11.
Incoming shortwave global radiation (Q g) and photosynthetically active radiation (PAR; Q pa as a fraction of full daylight, relative irradiance (%Q), were measured at the same time in young stands of Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.). Measurements were made on three levels above ground: 20 cm above ground and 50 and 15 % of stand height. Stands of three heights (75, 150 and 300 cm) were studied during two months. The stands were created by arranging young trees cut from natural stands, in nine quadratic spacings: 0.1, 0.2, 0.3, 0.4, 0.5, 0.7, 1.0, 1.4 and 2.0 m. The leaf area index (L) was estimated. Differences in %Q‐values for Q pa and Qg in the same species and at the same stand height and level of light measurements above ground were significant only in 150 and 300 cm stands. In 75 cm high stands of Scots pine, the %Q was <60% at spacings <0.2 m and in 75 cm high stands of Norway spruce, the %Q was <60% at spacings <0.3 m. Only at 0.1x0.1–0.3x0.3 m, %Q was <20% in Norway spruce stands. In 150 cm stands %Q<20% was measured at spacings <0.7 m in Norway spruce and <0.5 in Scots pine. In 300 cm stands of Norway spruce it was measured up to 1.2 and in Scots pine <1.1 m. Light extinction coefficients, K and Kg for spruce and pine stands were 0.17–0.40 and 0.16–0.31 respectively. Some practical implications of the study are presented. Lack of light (%Q<10%) as a single factor of seriously suppressed growth and development of broad‐leaved plants and suckers by competition in young stands of spruce and pine only occur in dense stands 0.3x0.3 m‐1.1xl.l m (8000–100000 stems/hectare). Competition by light on a regenerated area generally occurs in the level of 50% of tree height (150–300 cm) and higher due to the rapid growth of broad‐leaved trees (sprouts) compared with planted conifers but the light intensity at these levels %Q>10%.  相似文献   

12.
《中国林学(英文版)》2004,6(4):F003-F003
Chinese parasoltree (Firmiana simplex (L.) W. Wight) is a deciduous tree and belongs to the family Sterculiaceae. Its bark is green and smooth with vertical thin pale stripes. Its leaves are simple, alternate,deciduous, large, deeply palmately lobed with an entire margin and long stout petiole. F. simplex is andromonoecius. It flowers are in yellow terminal panicle, blooming in June and July.  相似文献   

13.
Aloe vera Linn. (Syn. Aloe barbadensis Mill; Gwar-patha in Hindi) belongs to family Liliaceae. The plant, for its medicinal properties, has commercial value. Some of the genotypes of Aloe vera are consumed as a vegetable and processed to make curry and other edible products. We report here on the development of an efficient method for rapid clonal propagation by shoot proliferation from axillary meristem(s) of selected germplasm of Aloe vera. Explants were pretreated with 0.1% aqueous solution of both streptomycin and bavistin separately, each for 15 min. These were surface sterilized with 0.1% aqueous solution of mercuric chloride (HgCl2) for 4–5 min and washed several times with autoclaved water. These were kept in a chilled, sterile antioxidant (200.0 mg L?1 of ascorbic acid, 50.0 mg L?1 of citric acid, and 25.0 mg L?1 of polyvinylpyrrolidone; PVP) solution and cultured on semi-solid Murashige and Skoog's (MS) medium. The bud explants produced multiple (10.3 ± 0.675/explant) shoots on MS medium containing 13.32 μM of 6-Benzylaminopurine (BAP) and 100.0 mg L?1 of ascorbic acid, 50.0 mg L?1 each of citric acid and PVP, with 25.0 mg L?1 each of arginine and adenine sulphate as additives. The shoots were further multiplied by (a) repeated transfer to fresh MS medium with additives + 13.32 μM BAP, and (b) subculturing on MS medium with a lower (4.44 μM) concentration of BAP. On MS medium containing 4.44 μM of BAP and additives, a maximum number (27.8 ± 0.63) of shoots were produced. In liquid MS medium with 4.44 μM of BAP, the rate of shoot multiplication increased and the vigor of the shoots improved. One hundred percent of the cloned shoots rooted under in vitro conditions on hormone-free half-strength MS salts containing 200.0 mg L?1 of activated charcoal at 32 ± 2°C. The cloned shoots treated with 2.46 mM of indole-3-butyric acid (IBA) or 2.473 mM of β-naphthoxyacetic acid (NOA) for 5 min rooted under ex vitro conditions in the greenhouse. The rooted plants were hardened in the greenhouse and stored under an agro-net house. The cloned plants were transferred under different field conditions at various sites in Western Rajasthan. These plants grew normally. The higher rate of shoot multiplication and easier approach of direct rooting and hardening make this method superior to the methods previously reported on cloning/tissue culture of Aloe species. From a single shoot bud, approximately 5000 plants can be produced within 180 days.  相似文献   

14.
Twigs of 2–3-year-old Platanus occidentalis L. were used as experimental material to find the causes for the contamination and browning in the initial stages of tissue cultures. To compare the degree of browning of explants picked off from different growing seasons, the experimental material was excised from trees on each of the first ten days in January, March, May and July, 2006. The results indicated that the contamination and browning rates of the material cut off in January (14.2% and 30.6%, respectively) and March were somewhat lower than those in July. The pretreatment of soaking the explants in different anti-oxidants and absorbents at the same time could diminish some side effects. The pretreatment of using 10 g·L–1 vitamin C reduced the contamination and brown-ing rate effectively. An orthogonal experiment showed that the optimal factor and level arrangement is 0.5 mg·L–1 BA, 2.0 g·L–1 ac-tive carbon and 1.5 g·L–1 PVP which resulted in a browning rate of only 16.5%. In general, sampling period, physical properties and pretreatment of explants are the main factors responsible for the contamination and browning of material in the initial stages of P. occidentalis tissue cultures.  相似文献   

15.
A survey on the symptom and severity of the leaf spot disease of Pongamia pinnata L. was conducted in the nurseries of the Institute of Forestry and Environmental Sciences, University of Chittagong (IFESCU), Bangladesh Forest Research Institute (BFRI) and Aronnak Nursery in Chittagong. The highest infection percentage and disease index were found in IFESCU nursery, followed by BFRI and the lowest was recorded in Aronnak nursery. The associated organism of leaf spot disease of P. pinnata was isolated from the diseased plant parts and the pathogenicity was established with the isolated fungus. Colletorichum gloeosprioides Penz was proved to be pathogenic. The inhibition of mycelial growth of C. gloeosporioides was observed and identified as suitable fungicides (Bavistin, Cupravite and Dithane M-45) and doses (0.05, 0.10, 0.50, 1.00, 1.50 and 2.00). The lowest and highest mycelial growth were respectively found on Bavistin and on Cupravite at the concentration of 0.05 after 8th day of incubation. It indicates that out of the three tested fungicides, Bavistin showed most effective, followed by Diathane M-45, and Cupravite was ineffective for its very little inhibition on mycelial growth.  相似文献   

16.
First‐year seedlings of five latitudinal populations of Acer platanoides were subjected to decreasing photoperiod treatment under three different temperature regimes. The depth of the induced dormancy was quantified as the number of days to bud burst (DBB) under defined conditions favourable to growth. The results suggested a close relationship between autumn temperature and the strength of the induced dormancy, with high temperatures combined with short days leading to a deeper stage of dormancy. Northern and continental populations generally had bud burst earlier than southern. The results are discussed in relation to hypotheses for dormancy induction and release.  相似文献   

17.
The injury tolerance of cell plasma membrane and the correlative enzymes activities of plasma-membrane protection system in the Ulmuspumila leaves treated by nine concentrations (0.3%, 0.6%, 0,9%, 1,2%, 1.5%, 1.8%, 2,1%, 2.4%, 3.0%) of Na2CO3 and NaHCO3 mixtures were studied in a greenhouse of Northeast Forestry University, Harbin, China. The rate of electrolyte leakage (REL) and SOD (Superoxide dismutase) activity in leaves of different samples were determined. Results showed that the REL in leaves of U. pumila presented a slowly increasing trend at the salt concentrations less than 1.5%, which indicated that cell plasma membrane of U. pumila leaves had rather strong resistance to the injury of salt ion, and had a significant increase at the salt concentrations more than 1.5%. The SOD activities in leaves of U, pumila presented an increased trend at salt concentrations less than 1.5%, the growth of seedlings did not decline, and tress and leaves had no symptom of injury, while the salt concentrations exceeded 1.5%, SOD activities sharply decreased and REL increased promptly.  相似文献   

18.
The aim of this research was to evaluate the effects of osmopriming and different hydropriming treatments on the vigour and germination of China aster(Callistephus chinensis) seeds. Seed vigour and germination tests were conducted at 10,20 and 30°C in darkness for untreated,osmoprimed and hydroprimed seeds. The following parameters and categories of seeds and seedlings were evaluated:the mean germination time(MGT) ,T10,T50,U75-25,U90-10,the percentage of germinating seeds(Gmax) ,germination capacity,percent...  相似文献   

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