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1.
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   

2.
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   

3.
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   

4.
Three test series were planted on sites selected for their contrasting properties to study the genotype × site interaction. Various clones of Salix alba (8 clones in the 1980 series), S. dasyclados (8 clones in 1982 series) and S. viminalis (6, 9, 13 clones in the various series) were included. Growth capacity, survival and infection by rust fungi were analysed. Interspecific variation was seen at some of the sites in the 1982 series but it was pronounced in the 1980 series where 5. viminalis outgrew 5. alba at all sites. Intraspecific variation could be seen for growth capacity, survival and rust resistance. A genotype × site interaction was detected for all variables studied. Some of the interaction, especially at the species level, can be explained by the variation in susceptibility to rust fungi and preference for soil types. In the breeding work with Salix the genotype × site interaction must be considered.  相似文献   

5.
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   

6.
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   

7.
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   

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

9.
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   

10.
Old provenance experiments with Scots pine and Norway spruce in Finland were used for assessing the long‐term effects of the projected climatic change on forest trees. The northernmost origins showed an increase in wood production when transferred southwards into a climate with an annual mean effective temperature sum close to that which is expected in northern areas as a result of the projected climatic change. A model is constructed with the estimated changes in wood production as a function of the annual mean temperature sum at the original location and the change in the annual mean temperature sum caused by the geographical transfer. The major changes in wood production are expected to occur in the northernmost areas of tree growth.  相似文献   

11.
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   

12.
13.
Total genomic DNA was extracted from leaves of Ginkgo biloba L. by the method of hot CTAB. After determining quantification of DNA sample by microclorimetric spectrophotography, Arabidopsis-type telomere primer and Sau3AⅠ cassette primer were used to isolate telomere-associated sequences from G. biloba L. by the method of cassette-ligation-mediated polymerase chain reaction (PCR). Using this method, two telomere-associated sequences, TAS1 and TAS2, were isolated. The authors preformed Southern hybridization of EcoRⅠ-treated G. biloba genomic DNA with each clone. The hybridization pattern showed that the clones obtained were derived from G. biloba genomic DNA. There are the Arabidopsis-type TTTAGGG tandem repeats in telomeres of G. biloba.  相似文献   

14.
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   

15.
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   

16.
Three different LED lamps with continuous spectra were compared against commonly used fluorescent lights. The lamps were characterized by light output, energy consumption and spectral quality for plant growth. The biological effects of light quality were compared by pre-cultivating seedlings of Picea abies (L.) Karst. and Pinus sylvestris L. under each spectrum for 35 days in a growth chamber with controlled temperature, humidity and photoperiod. The seedlings were then transplanted and cultivated for one vegetation period at the nursery, then planted outdoors on a forest field trial and followed for three years. The seedlings showed similar growth performance for all spectra tested. LED lamps have several advantages to fluorescent light such as energy consumption, longer life span and adjustable light intensity. Regarding light intensity the effects on growth performance were studied for both species using the most promising LED spectra. The photosynthetically active radiation (PAR) was maintained at 50, 100, 200 and 400 μmol?m?2?s?1. Unlike energy consumption, seedling development did not display a linear relationship to light intensity. Instead, the results show an optimum light level between 100 and 200?μmol?m?2?s?1 for the shade tolerant Picea abies seedlings and a level of around 200?μmol?m?2?s?1 for the more shade intolerant Pinus sylvestris seedlings.  相似文献   

17.
The objective of this study was to analyse the conditions for forest production on open, low‐production peatlands in Sweden with respect to climate, and water and nutrient regimes. The study focused on survival and growth of Scots pine (Pinus sylvestris L.) seedlings, planted 18 yrs ago in five experimental areas evenly distributed between south and north Sweden. Different ditch spacing and NPK fertilizer treatments were combined systematically in all experiments. Survival was positively correlated with temperature sum, fertilization and drainage intensity. Tree growth was not influenced by variations in temperature sum after merely draining, but in combination with fertilization, growth was strongly correlated with climate. In the southern experiments, fertilization increased stand growth eight to nine times, whereas stands on the northern sites did not respond to fertilization. The most important fertilizer element was P. The application of N had no effect on growth. More intensive drainage increased stand growth by 60%. In the southern areas, height development in the most intensive drainage and fertilizer treatments indicates a mean annual increment of 6–7 m3 ha?1, and no sign of decline in growth was seen. Turf‐planting had positive effects on both survival and growth, especially in less intensively drained plots. A large proportion of damaged trees was observed in the experiment. The frequency of damaged trees was positively correlated with treatment intensity but negatively correlated with temperature sum. The results show clearly that merely draining is not sufficient for successful afforestation of low‐production peatland sites. Fertilization by P and K is a necessary prerequisite, but the effect of fertilization varies with climatic conditions, probably owing to the amount of plant‐available N.  相似文献   

18.
The implementation of a management-protection program, using suitable cultivation practices, contributes to rehabilitating marginal areas prone to prolonged waterlogging and preserving biodiversity. Three hybrid poplar clones (‘I-488’, ‘Rimini’ and ‘D-64’) were tested to assess their degree of tolerance to waterlogging by imposing four water regimes over a 1?year period: control (C), non-preconditioned (NPr), and two levels of flood preconditioning (Pr10 and Pr20). During the 2nd?year, waterlogging (1.9?±?0.7?mg/l O2) was imposed on plants from NPr, Pr10 and Pr20 treatments for 60?days followed by drainage. Survival rate, dry mass production, net photosynthesis and relative damage to membrane structural integrity were evaluated. The treatment response varied among clones and levels of preconditioning. Less pronounced damage to ‘I-488’ clones in comparison to those of ‘Rimini’ and ‘D-64’ indicates its superior tolerance to waterlogging. Preconditioning treatments (Pr20) and, to a lesser extent (Pr10), significantly improved the ability of the clones to tolerate flooding, suggesting that the application of a Pr20 preconditioning treatment in the nursery before outplanting would give hybrid poplar clones the morpho-physiological advantages necessary to counteract the arduous conditions on inundated sites.  相似文献   

19.
After‐effects of maternal soil treatment, controlling for photoperiod and weather conditions, were tested in a nursery experiment with Pinus sylvestris L. seedlings. Three full‐sib crosses were replicated in 4 different soil treatment plots of a grafted experimental seed orchard (63"54'N). Weight of filled seeds, percentage of empty seeds, first year hypocotyl and epicotyl length, and autumn frost hardiness (from artificial freeze testing) were evaluated. Systematic effects from maternal soil treatment were small compared to family differences for all characters studied. However, epicotyl length of the progenies showed a positive relationship with N needle content of the mother grafts. The results also indicated an important interaction between maternal soil treatment and autumn frost hardiness of the families. It is suggested that the altered mother tree treatment could lead to a change in progeny performance, corresponding to a 1.5 degree difference in latitudinal origin of natural stand seedlings. The results demonstrate the advantages of providing the mother tree with uniform conditions in early progeny testing.  相似文献   

20.
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   

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