牡丹‘乌龙捧盛’组培苗生根及生根解剖学研究

The tissue-cultured seedlings of tree peony ‘Wulong Pengsheng’ were used to study the effects of different plant growth regulators, culture methods, and holdfast on rooting. The morphological structure change during rooting was also observed using the method of paraffin section. The result showed that the best combination of plant growth regulators for rooting was IBA 3.0 mg·L^-1 + NAA 0.6 mg·L^-1. The treatment under the temperature of 4℃ for ten days was benefit to rooting, and the rate could reach 75.67%. It was identified that the adventitious root primordia of shoot in vitro originated from the vascular cambium cells, especially, the cross areas of cambium and pith ray and they started to differentiate at the 5th day and lasted to the 12th day. If the shoots were cultured in the root inducing medium for 12 days, it would lead to not only descend of rooting rate, but also showing callus of stem base, and leaf senescent. However, if they were transferred into the medium without hormone in time, the root primordial protruded the epidermis and developed normally after 5 days’ culture.     

喷施营养液和NaHSO3对'蓝星'高山桧扦插生根的影响

In this study, we investigated the optimal concentration of nutrient-mist and NaHSO₃ for cutting propagation of Juniperus squamata 'Blue Star' , as well as the variation in the contents of chlorophyll in leaves, and solubility carbohydrate,soluble protein and other nutrition in leaves and bases of cuttings during rooting. Cuttings of grade Ⅲ (the lenghth of cutting bases lignified from 0.1 to 0.2 cm) was treated by 1/4MS+NaHSO₃(200 mg·L^-1),and the rooting rate rose 35% and root qualities were improved compared with control experiment, for there were different effects among three grade cuttings. The treatment of grade Ⅲ cuttings also resulted in higher content of soluble sugar and starch of those bases during rooting, especially obviously different for fifteen days, but less effect on the chlorophyll and some nutrition content of cutting leaves.     

不同品种油茶嫁接苗根系生长动态研究

The growth dynamics of root system and aboveground of the grafted seedlings of different Camellia oleifera cultivars are studied by skeleton method and root scanning. The results of 8-months’ observation on grafted seedlings of 5 C. oleifera cultivars showed that: the growth of aerial parts and root of the C. oleifera seedlings were not entirely in sync, during the time of low temperature from November to February, the root system still in sustained growth though the aerial parts of the 5 cultivars grew slowly. Remarkable differences were existed in root length, root surface area, root volume, root biomass and other indicators after 11-months’ growth. The mean value of total length of root-system was up to 243.3 cm and 143.4 cm for the minimum, the mean value of total root surface area was up to 50.2 cm² and 31.7 cm² for the minimum, the mean value of root volume of the C. oleifera seedlings was up to 0.843 cm³ and 0.578 cm³ for the minimum which lived 11 months after grafting. All the root length, root surface area, root volume of the 5 cultivars have remarkable differences.     

Vegetative propagation of Prunus africana: effects of rooting medium, auxin concentrations and leaf area

The region of West and Central Africa is endowed with high-value fruit trees and medicinal plants, which are currently traded locally as well as on regional and international markets. Unfortunately, they are all exploited from the wild and there has been little or no focussed effort to domesticate and cultivate them. Prunus africana is one of these important medicinal plant under domestication. A series of nursery experiments were conducted to assess the effects of rooting medium (sawdust, sand and a 50:50 mixture of sand and sawdust), auxin concentration (0, 50, 100, 150, and 200 μg IBA), and leaf area (0, 5, 10, 20, and 25 cm²) on rooting success of juvenile cuttings of P. africana. The percentage of cuttings rooted was significantly greater (P < 0.05) in sawdust (80%), than in sand alone (72%) or in mixture with sawdust (71%). Leaf area also significantly affected the percentage of rooting. Leafless cuttings did not root and were all dead by week 6, but in leafy cuttings rooting ability increased proportionally with leaf area up to 20 cm² (79%). Larger leaf cuttings (25 cm²) rooted at the same level as those of 20 cm². The cuttings with the largest leaves also had the greatest mean number of roots per cutting (14 roots cutting⁻¹), while those with the smallest (5 cm²) leaf area produced the fewest roots (5 roots cutting⁻¹). The application of auxin (IBA) promoted rooting (P < 0.05) up to an optimum application of 100–200 μg IBA per cutting, but 300 μg was supraoptimal. It can be concluded that P. africana is amenable to vegetative propagation. This revised version was published online in June 2006 with corrections to the Cover Date.     

Low temperature, IBA concentrations and optimal time for adventitious rooting of Eucalyptus benthamii mini-cuttings

Eucalyptus benthamii is a forest species of economic interest that has difficulty with seed production and also is considered to have difficulty with adventitious rooting using propagation techniques,such as cutting or mini-cutting.We aimed to assess the adventitious rooting percentage under different storage times in low temperatures and at various IBA(indole-3-butyric acid) concentrations to determine the optimal time of permanence for rooting Eucalyptus benthamii minicuttings in a greenhouse.Shoots collected from mini-stumps cultivated in a semi-hydroponic system were used to obtain the mini-cuttings.For the first experiment,the mini-cuttings were stored at 4℃ for 0(immediate planting),24,48,72,96 and 120 h.The second experiment evaluated the rooting dynamic to determine the optimal time of permanence for minicuttings in a greenhouse.The basal region of the mini-cutting was treated with various IBA solutions:0(free of IBA),1,000,2,000,3,000 and 4,000 mg·L-1.Every seven days(0(immediate planting),7,14,21 and 28 days),destructive sampling of the mini-cuttings was performed to evaluate the histology of the adventitious rooting.Eucalyptus benthamii minicuttings should be rooted immediately after the collection of the shoots.The 2,000 mg·L-1 IBA concentration induced a greater speed and percentage of adventitious rooting,and an interval of 35 to 42 days was indicated for permanence of the mini-cuttings in the greenhouse.Exposure to low temperature induced adventitious root formation with diffuse vascular connections.     

不同基质配方对金叶榆容器苗质量的影响

Through Ulmus pumila cv. 'Jinye’ container-growing seedling cultivation experiment with 4 types of media or 9 media formulas, the seedling height, the stem and crown diameter indexes of U. pumila cv. jinye were measured. These indexes were significantly or extreme significantly different among various media. The growth of seedling root system varied with different media. The rooting and root number in soft media were much better than that in dense media. According to the growth traits of above-ground and underground parts of U. pumila cv. jinye seedlings, the medium suitable for U. pumila cv. jinye seedling growth was defined as media type I, whose ratio of C/N was 17.7—18.1, the density was higher than 0.26 g·cm^-3. Grown on this medium, the height, stem diameter and crown diameter of U. pumila cv. jiny were 1.34—1.57 m, 1.36—1.50 cm and 59.6—73.9 cm, respectively. The results of experiment showed also that the physical property played an active role in cultural media, so a good initial medium could provide great assistance of fertilization and water management in seedling culture.     

花吊丝竹组培快繁育苗技术研究

The rapid propagation technology of Dendrocalamus minor var. amoenus was studied by investigating the effects of some factors such as selection of explant, phytohormone, culture method etc. The results show that: The best month for explant collection of D. minor var. amoenus is May and June. The best position for explant collection is middle-upper part knot of semi-lignification branch. The clump shoot could be induced in medium with 3/4MS+BA 4 mg·L^-1+KT 1 mg·L^-1+CW 100 mL·L^-1. The optimal medium for subculture of D. minor var. amoenus is 3/4MS+BA 2 mg·L^-1+KT 1 mg·L^-1+CW 100 mL·L^-1. Liquid medium is beneficial for improving growth condition and proliferation rate of clump shoot. The medium 1/5MS+IBA 8 mg·L^-1+ NAA 4.5 mg·L^-1 + KT 0.1mg·L^-1 is a relative suitable rooting medium for D. minor var. amoenus, with the rooting method of synchronized treatment first and then rooting. The survival rate of seedlings could be higher than 90% in substrate of fine river sand∶peat soil=3∶ 1.     

Regeneration and gene transformation systems of Robinia pseudoacacia ‘Idaho’ mediated by Agrobacterium tumefaciens

Robinia pseudoacacia ‘Idaho’ is one of several multi-purpose trees used in ornamental, soil and water conservation, fodder and nectar sources. Plant abiotic stress tolerance transformed by genes could meet the requirements for reclamation of arid or alkalid lands and vegetation restoration. For this paper, we studied the effects of auxin and cytokine on Idaho locust in vitro regeneration and the establishment of gene transformation systems for plants mediated by Agrobacterium tumefaciens. Results showed that the ratios of cytokinin and auxin were the major factors affecting adventitious bud differentiation on a MS medium; the concentration of 0.5 mg&#8226;L^–1 6-BA benefitted callus proliferation and 0.25 mg&#8226;L^–1 IBA promoted shoot rooting; however, a higher IBA concentration will inhibit rooting. The most effective antitoxin for screening transgenic Idaho locust shoots was G418 and the most sensitive concentra-tion of it was 8 mg&#8226;L^–1.     

4种山茶花营养成分及有害元素含量分析

The nutritional components and poisonous elements in flowers of Camellia chekiangoleosa, C. polydonta, C. semiserrata and C. azalea were studied. The results indicated that the soluble sugar content of the four Camellia flowers had no difference. The maximum protein content was 82.9 g·kg^-1, detected in the flower of C. semiserrata. And the minimum protein content was 56.8 g·kg^-1, found in C. azalea. Vitamin C and β-carotene contents in C. azalea and C. semiserrata were higher, and in C. polydonta and C. chekiangoleosa were lower. The total amino acid contents of the four Camellia were 68.41、67.26、50.77、66.87 g·kg^-1 respectively, the essential amino acid contents were 33.86、32.70、27.21、33.79 g·kg^-1 respectively, and the proportion of essential amino acid in total amino acid of the four Camellia were 49.50%, 48.62%, 53.59% and 50.53% respectively. The contents of Ca, Mn and Cu in C. chekiangoleosa were the highest. Zn and Se contents were the maximum and Ca was the minimum in C. polydonta. The contents of Fe and Se were the lowest in C. semiserrata. Fe content were the maximum and Mn, Zn and Cu the minimum in C. azalea. The trace element contents in the flower of the four Camellia species followed the order of Mn, Fe, Zn, Cu, Se, but the content of Fe was higher than that of Mn in C. azalea. The contents of Pb, Cd, As and Hg of the four Camellia flower were all lower than the permissible amount.     

苗期寄主配置对印度檀香幼苗生长影响的研究

The effects of pot host (Kuhnia rosmarinifolia) configuration on the growth of Indian sandalwood (Santalum album L.) seedlings were studied by container culture experiment using split plot design. ANOVA results showed that the configuration time of pot host affected the height (p<0.001), ground diameter (p=0.038), biomass (p=0.039) as well as haustoria amount (p=0.016) of S. album seedlings significantly after 5 months’ growth, while statistically differences were not found for the quality index (p=0.120). The amount of K. rosmarinifolia as well as the interaction between amount and configuration time did not show significant differences on the above indices. Earlier configuration of the pot host was good for the growth of S. album, and it was the best when disposing the pot host in the same time with the transplantation of S. album seedlings from seed bed to containers. In consideration of nursery practices, the ideal pot host amount was 2 or 3, under such a configuration model, the growth of S. album seedlings achieved the best performance for most indices, including an average height of 29.43 cm, an average ground diameter of 0.41cm, an average biomass of 3.06 g, an average haustoria number of 151, and an average quality index of 0.402 after 5 months growth.     

不同激素处理和基质配方对楸树嫩枝扦插生根的影响

在计算机智能控制温室中,保证生根期空气温度18～28℃,空气相对湿度90％～95％,以圆基长果楸为材料进行了楸树嫩枝扦插对比试验并对生根率及生根性状进行了研究.对比了ABT-1和NAA两种激素的不同浓度、不同处理方法、不同处理时间的组合,以及泥炭、珍珠岩、河沙、蛭石不同配比的基质组合对生根的影响.结果表明:1 000 ...     

Can prescribed fire be used to maintain fuel treatment effectiveness over time in Black Hills ponderosa pine forests?

We determine the time frame after initial fuel treatment when prescribed fire will be likely to produce high enough mortality rates in ponderosa pine (Pinus ponderosa var. scopulorum Dougl. ex Laws.) regeneration to be successful in maintaining treatment effectiveness in the Black Hills of South Dakota. We measured pine regeneration in disturbed stands and young pine growth rates to estimate the susceptibility of pine regeneration to prescribed fire with time since initial treatment. We also determined surface fuel accumulation rates for stands after prescribed fire to help estimate likely fire behavior in maintenance prescribed fire. Given our estimates of regeneration density and tree size, and likely fire behavior, we then used small pine tree mortality—fire effect relations to estimate the effects of prescribed fire on developing understory pine at specific times since initial treatments.     

腾冲红花油茶果实成熟度及堆沤处理对油产量及其品质的影响

选择38个腾冲红花油茶优株,设置八成熟采果、近生理成熟采果与及时脱粒、堆沤12d后脱粒组合而成的4种果实采收脱粒处理,对其主要产量、品质指标进行测定和分析.结果表明:4种处理间产量、品质达极显著差异(P＜0.01);果实八成熟采收导致产量严重损失,其仁油率、籽油率、果油率分别降低11.9％、18.2％和31.7％,籽油酸价亦降低10.5％而利于储存;近生理成熟采收“堆沤”处理与及时脱粒比较,其仁油率降低4.5％,而籽油酸价则提高7.3％;因此,腾冲红花油茶果实宜在生理成熟时采收并及时脱粒.研究结果为确定腾冲红花油茶果实合适采收期和采后处理方式提供了技术依据.     

Aromatic plant-derived essential oil: an alternative larvicide for mosquito control

Five aromatic plants, Carum carvi (caraway), Apium graveolens (celery), Foeniculum vulgare (fennel), Zanthoxylum limonella (mullilam) and Curcuma zedoaria (zedoary) were selected for investigating larvicidal potential against mosquito vectors. Two laboratory-reared mosquito species, Anopheles dirus, the major malaria vector in Thailand, and Aedes aegypti, the main vector of dengue and dengue hemorrhagic fever in urban areas, were used. All of the volatile oils exerted significant larvicidal activity against the two mosquito species after 24-h exposure. Essential oil from mullilam was the most effective against the larvae of A. aegypti, while A. dirus larvae showed the highest susceptibility to zedoary oil.     

Photosynthetic characteristics of Fagus sylvatica and Quercus robur established for stand conversion from Picea abies

Efforts in Europe to convert Norway spruce (Picea abies) plantations to broadleaf or mixed broadleaf-conifer forests could be bolstered by an increased understanding of how artificial regeneration acclimates and functions under a range of Norway spruce stand conditions. We studied foliage characteristics and leaf-level photosynthesis on 7-year-old European beech (Fagus sylvatica) and pedunculate oak (Quercus robur) regeneration established in open patches and shelterwoods of a partially harvested Norway spruce plantation in southwestern Sweden. Both species exhibited morphological plasticity at the leaf level by developing leaf blades in patches with an average mass per unit area (LMA) 54% greater than of those in shelterwoods, and at the plant level by maintaining a leaf area ratio (LAR) in shelterwoods that was 78% greater than in patches. However, we observed interspecific differences in photosynthetic capacity relative to spruce canopy openness. Photosynthetic capacity (A₁₆₀₀, net photosynthesis at a photosynthetic photon flux density of 1600 μmol photons m⁻² s⁻¹) of beech in respect to the canopy gradient was best related to leaf mass, and declined substantially with increasing canopy openness primarily because leaf nitrogen (N) in this species decreased about 0.9 mg g⁻¹ with each 10% rise in canopy openness. In contrast, A₁₆₀₀ of oak showed a weak response to mass-based N, and furthermore the percentage of N remained constant in oak leaf tissues across the canopy gradient. Therefore, oak photosynthetic capacity along the canopy gradient was best related to leaf area, and increased as the spruce canopy thinned primarily because LMA rose 8.6 g m⁻² for each 10% increase in canopy openness. These findings support the premise that spruce stand structure regulates photosynthetic capacity of beech through processes that determine N status of this species; leaf N (mass basis) was greatest under relatively closed spruce canopies where leaves apparently acclimate by enhancing light harvesting mechanisms. Spruce stand structure regulates photosynthetic capacity of oak through processes that control LMA; LMA was greatest under open spruce canopies of high light availability where leaves apparently acclimate by enhancing CO₂ fixation mechanisms.     

Antibacterial activity of plant extracts from Brazilian southeast region

A screening was conducted with 26 plants collected in the Brazilian southeast region, to identify plant extracts with antibacterial properties against Aeromonas hydrophila, Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus. Initially, the agar diffusion method was employed. Then, those extracts presenting activity were submitted to a broth microdilution assay to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). It was observed that 13 of the tested extracts showed antibacterial activity. The best results were obtained with those from Lantana lilacina and Phyllanthus tenellus.     

Growth and physiological response of six Australian rainforest tree species to a light gradient

An understanding of growth and photosynthetic potential of subtropical rainforest species to variations in light environment can be useful for determining the sequence of species introductions in rainforest restoration projects and mixed species plantations. We examined the growth and physiology of six Australian subtropical rainforest tree species in a greenhouse consisting of three artificial light environments (10%, 30%, and 60% full sunlight). Morphological responses followed the typical sun-shade dichotomy, with early and late secondary species (Elaeocarpus grandis, Flindersia brayleyana, Flindersia schottiana, and Gmelina leichhardtii) displaying higher relative growth rate (RGR) compared to mature stage species (Cryptocarya erythroxylon and Heritiera trifoliolatum). Growth and photosynthetic performance of most species reached a maximum in 30–60% full sunlight. Physiological responses provided limited evidence of a distinct dichotomy between early and late successional species. E. grandis and F. brayleyana, provided a clear representation of early successional species, with marked increase in A_max in high light and an ability to down regulate photosynthetic machinery in low light conditions. The remaining species (F. schottiana, G. leichhardtii, and H. trifoliolatum) were better represented as falling along a shade-tolerant continuum, with limited ability to adjust physiologically to an increase or decrease in light, maintaining similar A_max across all light environments. Results show that most species belong to a shade-tolerant constituency, with an ability to grow and persist across a wide range of light environments. The species offer a wide range of potential planting scenarios and silvicultural options, with ample potential to achieve rapid canopy closure and rainforest restoration goals.     

Antimicrobial activity of some endemic plants growing in the Eastern Black Sea Region, Turkey

The Eastern Black Sea Region has an extensive flora because of ample rainfall lasting all year. In this study, antimicrobial effects of 74 crude extracts of 22 endemic plants were investigated. Among the 30 active crude extracts, water-insoluble crude extracts from Betula medwediewii, Heracleum platytaenium, Primula longipes, Anthemis cretica ssp. argaea and Centaurea helenioides were the prominent ones with their MIC values.     

利用三种梢栖真菌生物防治落叶松枯梢病的研究

从落叶松梢栖真菌筛选出对落叶松枯梢病病原菌有抑制作用的菌株,对落叶松枯梢病进行生物防治。将自落叶松梢部分离到的11种梢栖真菌与落叶松枯梢病病原菌进行对峙培养,根据被覆盖程度、抑菌率、拮抗系数和防治预试验的结果,综合评价后发现:粪生粪壳、深绿木霉和球毛壳3种梢栖真菌对落叶松枯梢病有良好的拮抗作用。利用这3个菌株在黑龙江省勃利县通天一林场国富沟进行林间防治试验,结果表明:防治效果为粪生粪壳>代森锰锌400倍液>深绿木霉>球毛壳;深绿木霉和粪生粪壳喷洒浓度50%和球毛壳喷洒浓度75%时,真菌多样性最多,梢栖真菌系统较其他浓度更为稳定,与化学防治相比,既达到了防治目的又具有不污染环境的优势。     

Growth and production varies between pair-wise mixtures and monoculture plantations in North Viet Nam

The potential benefits of species mixture were investigated using pair-wise comparisons of four timber tree species in northern Viet Nam. Chukrasia tabularis, Canarium album, Michelia mediocris and Eucalyptus urophylla were grown in monocultures and in pair-wise mixtures. The trial was established as a randomized block design with each treatment replicated four times. Volume production gain or loss in mixtures was assessed by calculating a mixture index, which is defined as Relative Yield Total (RYT). At age 48 months, the trial indicated mixed performance with both positive and negative impacts of growing some species in mixtures compared to monocultures. The largest gain was shown in the mixture of a shade-intolerant species, Chukrasia with a more shade-tolerant species, Michelia (47% gain in relative yield), and Eucalyptus with Michelia (45% gain in relative yield) at the first 38 months. The other three mixtures tested, and which were not successful (i.e. had lower relative yields) at 38 months, was the mixture of all shade-intolerant species, including Chukrasia with Canarium, Canarium with Eucalyptus and Chukrasia with Eucalyptus. This suggests that species with different shade tolerances can form complementary pair-wise mixtures, but this changed significantly (P < 0.05) over the following 10 months. At age 48 months the RYT of Chukrasia with Michelia increased by 12%, those of Michelia with Eucalyptus decreased by 20% at 48 months compared to 38 months, suggesting that Eucalyptus should be thinned at around year 5 years. Likewise, the RYT of Michelia with Canarium declined significantly by 23% at 48 months. The RYT of other tested mixtures remained almost unchanged over time.