The lectin gene TRpL1 of tetraploid Robinia pseudoacacia L.response to salt stress

Lectins are natural proteins in animals,plants,and microorganisms and can be divided into 12 families.These lectins play important roles in various environmental stresses.Some polyploid plants show tolerance to environmental stresses and to insect pests.However,the mechanism of stress tolerance is unclear.Tetraploid Robinia pseudoacacia(4×)under salt stress showed higher tolerance than diploid R.pseudoacacia(2×).As lectin can improve stress tolerance,it was questioned whether the stress resistance of polyploid plants was related to the lectin protein.In this study,salt resistance of lectin gene TRpL1 was verified by its over-expression in plants.In addition,salt resistance of lectin protein by E.coli strains was detected.The data revealed that the over-expression transgenic plants of TRpL1 showed better salt tolerance than control plants under salt stress,and the TRpL1-expressing strain also grew better in the medium with added NaCl.Therefore,tetraploid plants can resist salt stress through TRpL1 protein regulation.

贵阳市刺槐(Robinia pseudoacacia L.)树附生苔藓植物初步调查

在"林城"贵阳,贵阳市行政区域内现有林地面积18.3万hm2,森林覆盖率为31.7%,森林覆盖率较高。树附生苔藓植物因其特殊性是可以作为城市大气污染的指示植物。树附生苔藓在贵阳分布较广泛,其中以作为贵阳市行道树或栽种树的刺槐树(Robinia pseudoacacia L.)最为典型。在贵州师范大学、花溪公园以及黔灵公园3个地点共选取了13棵刺槐树进行野外生态调查。结果发现了树附生苔藓植物8科12属14种。常见种为全缘刺疣藓Trichosteleum lutschianum(Broth.et Par.)Broth.、平锦藓Platygyrium repens(Brid.)B.S.G.、细叶小羽藓Haplocladium microphyllum(Hedw.)Broth.、矮锦藓Sematophyllum subhumile(C.Muell.)Fleisch.、真藓Bryum ar-genteumHedw.、异叶红叶藓Bryoerthrophyllum hostile(Herz.)Che和纤枝短月藓Brachymenium exile(Doz.etMolk.)Bosch et Lac.等。优势科为真藓科,其次是灰藓科,分别占总数的50%和37.5%。生活型只有矮丛集型和交织型。本次对贵阳市刺槐树附生苔藓的初步调查为进一步深入研究贵阳市树附生苔藓的多样性提供了基础资料。也是对将来监测贵阳市大气污染迈出的重要的第一步。

外来物种刺槐(Robinia pseudoacacia L.)在中国的研究进展

刺槐作为一个外来种,近年来其研究受到越来越多的关注。本文介绍了刺槐在我国的基本生长特性(包括根系、种子、叶片、花)和在不同外界条件下(光照条件、盐胁迫、氮磷沉降、干旱胁迫、重金属胁迫、密度、AM真菌)的生理生态响应研究进展。探讨了刺槐病原菌引起的病害与防治、昆虫病害与防治、刺槐的有性、无性繁殖培育以及资源的开发利用,如薪炭材料、饲料、防风固沙、蜜源植物等,讨论了刺槐入侵理论与生态风险处理措施。评述了刺槐的区域性研究进展。最后提出了针对刺槐的未来研究展望。

Assessing Adaptability of Planted Trees Using Leaf Traits: A Case Study with Robinia pseudoacacia L. in the Loess Plateau, China

Leaf trait patterns and their variations with climate are interpreted as an adaptive adjustment to environment.This study assessed the adaptability of planted black locust (Robinia pseudoacacia L.) based on the analysis of leaf traits and the comparison of its leaf traits with inter-specific ones existing in the same area.We measured some water and N use related leaf traits: leaf dry mass per unit area (LMA) and N,P and K concentrations based on both leaf area (Narea,Parea and Karea) and leaf mass (Nmass,Pmass and Kmass) of R.pseudoacacia at 31 sites along a water stress gradient in North Shaanxi Province,China.The results show that leaves of R.pseudoacacia have high Nmass and low LMA in the study area.High Nmass and low LMA are usually representative of luxurious resource use,and will advance plant resource competitiveness in high-resource conditions.As a whole,LMA-nutrient relationships of R.pseudoacacia display patterns that are fairly similar to the inter-specific relationships in both direction and intensity.The tendency for LMA and Narea to increase with decreasing water availability and the positive correlation between LMA and Narea reflect the trend for R.pseudoacacia to enhance water use efficiency (WUE) at the expense of down-regulated photosynthetic N use efficiency (PNUE) and high construction cost in dry conditions.However,the positive relationship between LMA and Narea in high mean annual precipitation (MAP) area is either unremarkable or reversed with decreasing water availability.This implies a lower photosynthetic capacity and a higher construction cost for high-LMA leaves.The inter-specific relationship between LMA and Narea is positive and does not change with water availability.This difference between inter-species and intra-species may be due to more diversified anatomies and more specialised structures for inter-species than intra-species.The failure of R.pseudoacacia adaption to dry conditions reflected by LMA-Narea relationship may be partially responsible for the emergence of rampike and dwarf forms found frequently in dry conditions.Incorporating intrinsic characteristics of planted trees into vegetation restoration project will be instructive and meaningful for species selection.

Black locust(Robinia pseudoacacia L.)as a multi-purpose tree species in Hungary and Romania:a review

Black locust(Robinia pseudoacacia L.) was the first North-American tree species imported to Europe at the beginning of the seventeenth century. It is commonly planted worldwide because of its adaptability to environmental stresses, its valuable wood, easy propagation, frequent and abundant seed production, excellent coppicing,high seedling survival, and relatively high wood yield. In Europe, Romania and Hungary have the most highly-developed black locust growing techniques and experiences.As a result of increasing interest in black locust in many countries, this review aims to provide a comprehensive overview of state-of-the-art site requirements, propagation, improvement and management(including growth and yield as well as use in energy plantations).

匈牙利刺槐(Robinia pseudoacacia L.)改良的繁殖方法(英文)

在匈牙利,匈牙利刺槐(Robinia pseudoacacia L.)是重要的成林树种之一,且该树种的重要性在世界其它国家也日益增加。该树种的生产通常有两种方法:种子和根插条。组织培养对该种来说是一种相对较新的方法。对于在各种环境条件下大规模地生产苗木来说,种子栽培是相对简单的方法,机械化方法比较容易且生产成本相对较低。根插条和组织培养对于优势个体或品种繁殖是有价值的。利用这些方法,所选出的树木的优势品质可以在无性系得以保存。近期实验表明,微繁殖树木可以成功地移植到土壤中,在野外生长。

Effects of different supplements on tetraploid black locust (Robinia pseudoacacia L.) silage

Preparation of silage is a common method to preserve green forage.It plays an important role in improving forage utili-zation, solving the problem of forage provision and meeting the nutritional needs of livestock in winter and spring.The effects of various supplements on tetraploid black locust (Robinia pseudoacacia L.) silage were studied by analyzing its color, odor, texture, pH value, the composition and amount of organic acids, the ammonia-N/total-N ratio, crude protein, neutral detergent fibers and acid detergent fibers.Our results show that the silage quality of wilted tetraploid R.pseudoacacia preserved alone is acceptable, while adding brown sugar and Yishengkang to tetraploid R.pseudoacacia foliage improved its quality.The treatments consisting of the tetraploid R.pseudoacacia mixed with 33% and 50% corn stalk achieved the best silage quality in terms of pH value (p<0.01), amount of lactic acid (p<0.01), the ammonia-N/total-N ratio (p<0.01) and the fermentation quality.These treatments also resulted in a high content of crude protein and lower amounts of acid detergent fibers.The treatment consisting of the tetraploid R.pseudoacacia mixed with 20% corn stalk was also good in the quality of its fermentation.

Symbiotic nitrogen fixation in black locust (Robinia pseudoacacia L.) seedlings from four seed sources

We conducted a greenhouse experiment to investigate the role of seed source in growth and symbiotic nitrogen fixation of black locust (Robinia pseudoacacia L). Seeds from different sources were planted in the same environmental conditions and inoculated with a suspension of mixed Rhizobium. We used the modified 15 N isotope dilution method to estimate biological nitrogen fixation of Robinia trees. Different Robinia seed sources differed significantly in terms of tissue dry weight (50.6 80.1 g), total N (1.31-2.16 g) and proportion of nitrogen derived from the atmosphere ( 0-51%). A higher nitrogen fixation rate of Robinia trees was associated with higher dry weight. Moreover, the leaves of Robinia proved to adequately represent the nitrogen fixation capacity of entire plants. Our results confirmed that assessment of seed sources is a useful way to improve the nitrogen fixation capacity and therefore the growth rate of Robinia.

匈牙利刺槐((Robinia pseudoacacia L.)林的经营研究(英文)

匈牙利刺槐((RobiniapseudoacaciaL.)是在17世纪初从北美引入到欧洲的第一个森林树种。在匈牙利,刺槐是非常重要的速生树种,为经济和生态目的,可以成功营造刺槐人工林。结合该树种的生长特点选择营林措施,可以最大限度的提高刺槐人工林的成活率和生产力。本文根据林分结构和森林产量长期实验林的研究成果,提出了刺槐林的抚育作业次序。制定好的营林计划和模式将会培育出效益刺槐林,并能使土地经营者更好地接受该树种。同时,刺槐也是一个非常有用的能源生产树种,本文展示了对这方面的研究成果。图2表1参8。

Early evaluation of micropropagated black locust (Robinia pseudoacacia L.) clones in Hungary

In Hungary, black locust (Robinia pseudoacacia L.) is one of the most important exotic species, forming entire stands. Its importance is increasing in many other countries. As a result of a new selection program eight black locust clones have been improved for establishing clone trials and a seed orchard. In this study juvenile growth and stem quality of micropropagated clones of black locust were evaluated on a marginal site in central Hungary. At ten years old, the clones 'MB17D3/4' and 'PV201E2/4' appeared to be especially promising for high quality wood production under arid hydrological conditions. A tissue culture method can be considered a suitable tool of propagating superior individual trees and offers new prospects for the rapid cloning of selected genotypes.

Changes in diversity,composition and assembly processes of soil microbial communities during Robinia pseudoacacia L.restoration on the Loess Plateau,China

Robinia pseudoacacia L.(RP)restoration has increased vegetation cover in semi-arid regions on the Loess Plateau of China,but ecological problems have also occurred due to RP restoration,such as reduced soil moisture.Further,it is still uncertain how microbial diversity,composition and assembly processes change with RP restoration in semi-arid regions.Therefore,amplicon sequencing of small subunit ribosomal ribonucleic acid(16S rRNA)and internal transcribed spacer(ITS)genes was performed to study soil bacterial and fungal diversity,composition and assembly processes at four study sites with different stand ages of RP plantations(Y10,RP plantation with stand ages less than 10 a;Y15,RP plantation with stand ages approximately 15 a;Y25,RP plantation with stand ages approximately 25 a;and Y40,RP plantation with stand ages approximately 40 a)along a 40-a chronosequence on the Loess Plateau.The diversity of soil bacteria and fungi increased significantly during the restoration period from 10 to 15 a(P<0.05).However,compared with Y15,bacterial diversity was lower at Y25 and Y40,and fungal diversity remained stable during the restoration period between 25 and 40 a.The relative abundances of Proteobacteria and Ascomycota increased during the restoration period from 10 to 15 a.Conversely,after 15 a of restoration,they both decreased,whereas the relative abundances of Actinomycetes,Acidobacteria and Basidiomycota gradually increased.The variations in soil bacterial communities were mainly related to changes in soil total nitrogen,nitrate nitrogen and moisture contents,while soil fungal communities were mainly shaped by soil organic carbon and nitrate nitrogen contents.Bacterial communities were structured by the heterogeneous selection and stochastic process,while fungal communities were structured primarily by the stochastic process.The RP restoration induced an increase in the relative importance of heterogeneous selection on bacterial communities.Overall,this study reveals the changes in microbial diversity,community composition and assembly processes with RP restoration on the Loess Plateau and provides a new perspective on the effects of vegetation restoration on soil microbial communities in semi-arid regions.

Intensive Agricultural Practices as Enhancers of the Dispersion of Invasive Species:Notification of the Observation of a Case with Robinia pseudoacacia L.in Alentejo(Southern Portugal)

Invasive forest species are a recurring problem,which in Portugal assume a somewhat mediatic role,both because of the impacts they cause on biodiversity,but also because they enhance the accumulation of high amounts of fuel load,increasing the risk of forest fires.However,in some areas of the country,such as the Alentejo(South of Portugal),the scarcity of water did not allow,until now,the dispersion and rapid growth of some of these species,namely Robinia pseudoacacia,which has always remained under control,and it was never a real problem.However,with the growth of intensive farming practices,associated with vineyards,olive groves and almond trees,water and nutrients became available,enabling this species to grow and disperse.This communication presents an observation of several sets of R.pseudoacacia specimens growing with different agricultural holdings,raising the hypothesis that intensive farming practices may,in the short term,contribute to the dispersion of invasive species in regions where they were not a problem,if the situations reported are not followed up and studies are carried out to confirm the observations described.

Leaf C:N:P stoichiometric homeostasis of a Robinia pseudoacacia plantation on the Loess Plateau

Homeostasis is the adaptability of a species to a changing environment.However,the ecological stoichiometric homeostasis of Robinia pseudoacacia L.in diff erent climatic regions is poorly understood but could provide insights into its adaptability in the loess hilly region.This study sampled 20 year-old R.pseudoacacia plantations at 10 sites along a north–south transect on the Loess Plateau.Variations in the ecological stoichiometric characteristics of leaf and soil carbon,nitrogen,and phosphorus were analysed and homeostatic characteristics of leaf ecological stoichiometric parameters in diff erent climates were identifi ed.Factors aff ecting leaf stoichiometry were assessed.The results show that R.pseudoacacia leaves were rich in nitrogen and defi cient in phosphorous during tree growth and development.Nitrogen and phosphorous levels in the soils of the loess region were lower than the average in soils in the rest of China.All ecological stoichiometric parameters of R.pseudoacacia leaves in two diff erent climates were considered“strictly homeostasis”.Precipitation,available phosphorus,and soil C:P were the main factors aff ecting the variation of C:N:P stoichiometry of R.pseudoacacia leaves.R.pseudoacacia in the loess hilly region has strong ecologically homeostatic characteristics and suggests that it is well-adapted to the area.

Accumulation of heavy metal in Platanus orientalis, Robinia pseudoacacia and Fraxinus rotundifolia

Plants are capable of reducing environmental pollutions through uptaking contaminants in their tissues. In the study site, twenty one-year-old leaves and shoots as well as twenty soil samples were sampled and analyzed by Inductively Coupled Plasma (ICP). We investigated the uptaking ability of lead (Pb) and cadmium (Cd) by the leaves and shoots of Platanus orientalis, Robinia pseudoacacia and Fraxinus rotundifolia in Karaj city, the western Tehran, Iran. We also evaluated the total metal accumulation capacity by using metal accumulation index (MAI). Results indicated that there was no significant difference in uptaking contents of Cd and Pb in the leaves among the trees. However accumulation of Cd in shoots of F. rotundifolia and R. pseudoacacia was significantly higher than that of P. orientalis. The accumulation of Pb in shoots of R. pseudoacacia was significantly higher than the other species. The amount of Pb in the soil of the study area was significantly higher than Cd. Concentrations of Cd and Pb in leaves of the three species are in the ranges of 2.4 2.7 mg Kg-1 and 7.1 14.4 mg Kg-1 , respectively. R. pseudoacacia had the highest MAI value for leaves (2.21) and F. rotundifolia had the highest MAI value for shoots (2.4).

Impacts of mixed litter decomposition from Robinia pseudoacacia and other tree species on C loss and nutrient release in the Loess Plateau of China

The productivity of Robinia pseudoacacia(R.p.) pure forest usually declines at the late growth stage,and reforming it into mixed forests could be a promising way to resolve this problem. When choosing a suitable tree species that can be mixed with R.p., the interspecific relationship is an important issue. Therefore, we gathered the autumn litter fall from R.p. and 10 other species from the Loess Plateau of China were mixed in dual species litterbags(R.p.+each other species) and buried them in soil for a 345 days lab decay incubation. We measured the litter mass loss and nutrient contents to determine whether the nutrient release was affected by mixed species litter decomposition. The impacts of mixed litter decomposition on macro-elements release were more obvious than on micro-elements. The litters with similar substrate quality might show variable impacts on nutrients release in mixed decomposition. The C loss and release of nutrient was improved by descending order when R.p. litter was mixed with Hippophae rhamnoides, Ulmus pumila, Populus simonii, Larix principis-rupprechtii and Quercus liaotungensis(Q.l.). But, except for Q.l., only the other species were recommended as suitable mix-plants for R.p. since promoting a high turnover of the nutrient in the litter compartment and a rapid availability for tree.

Selection and characterisation of lactic acid bacteria isolated from different origins for ensiling Robinia pseudoacacia and Morus alba L.leaves

The objective of this study was to isolate lactic acid bacteria(LAB) strains from different origins and to select the best strains for ensiling Robinia pseudoacacia(RB) and Morus alba L.(MB)leaves. The LAB strains were inoculated into the extracted liquid obtained from RB and MB leaves to evaluate the fermentation products. 11 LAB strains were selected for further experiments based on the highest products of lactic or acetic acid, including 1 strain of Weissella confusa, 2 of Lactobacillus reuteri and 8 of Lactobacillus plantarum.The API 50 CH fermentation experiment indicated that all of the selected 11 LAB strains utilised most of the carbohydrates. All the strains grew at temperatures between 10 and 45°C and at a p H of 3.5 to 4.5; however, L. reuteri F7 and F8 tolerated a p H as low as 3.0. All 11 LAB strains showed antibacterial activity against Listeria monocytogens, Escherichia coil, Salmonella sp. and Acetobacter pasteurianus; however, after excluding the effect of organic acids, only F7 and F8 still exhibited antibacterial activity. The present study indicated that the selected 11 LAB strains could be used to prepare silages of RB and MB leaves, especially L. reuteri F7 and F8.

Nutrients of green and senesced leaves of a Robinia pseudoacacia plantation along a latitudinal gradient on the Loess Plateau,China

Plantations have been widely established to improve ecosystem services and functioning.Black locust,Robinia pseudoacacia L.is a common,widely planted species to control soil erosion on the Loess Plateau.Previous studies have focused on economic values but the interactions between soil and plant carbon(C),nitrogen(N)and phosphorus(P)remain unknown.Investigating variations of soil,green and senesced leaf C,N and P levels in R.pseudoacacia along a latitudinal gradient is useful to understanding its ecological functions.The results show that soil C,N and senesced leaf N and P significantly decreased with an increase in latitude,but there were no significant changes in the senesced leaf C and soil P.The resorption efficiency of N was related with latitude and soil N levels,and the relation between green leaf N and soil N was significant.These relations suggest that soil N was the key in affecting green leaf N levels.At higher latitudes,senesced leaves had lower N levels associated with higher N resorption efficiency to maintain a stable N content in green leaves.With a decrease of soil N,R.pseudoacacia can enhance N resorption efficiency to meet the demand of growth.Thus,it is an important species for reforestation,especially in nutrient-poor environments.

Robinia pseudoacacia leaves improve soil physical and chemical properties

The role of the leaves of Robinia pseudoacacia L., which is widely distributed in the arid lands, on improving soil physical and chemical properties was analyzed at various incubation periods. The incubated soils added with 0, 25, 50 and 75 g Robinia pseudoacacia leaves were tested after consecutive incubation intervals of 6, 8 and 10 months and the different soil parameters were measured. The results showed the increases in organic matter (OM), extractable K, cation exchange capacity (CEC), aggregate stability and water holding capacity, but the decreases in pH value and bulk density after 6 months' incubation. The gradual decrease in change rates of soil properties indicated less microbial population and organic residual mineralization under acidic conditions, which were resulted from fast decomposition of leaves after the first 6 months incubation. The increases in soil organic matter content, extractable K, CEC, aggregate stability and water holding capacity and the decreases in soil pH and bulk density provide favorable conditions for crop's growth.

Cadmium and lead effects on chlorophyll fluorescence,chlorophyll pigments and proline of Robinia pseudoacacia

Heavy metal contamination is one of the most important abiotic stresses affecting physiological activities of plants.We investigated the effects of cadmium(Cd) and lead(Pb) on chlorophyll fluorescence(Fv/Fm,Fo,and Fm),photosynthetic pigments(chlorophyll a and b),and proline in one-year-old seedlings of Robinia pseudoacacia.The seedlings were treated twice over a period of 10 days with Cd and Pb at concentrations of 0,250,500,1000 and2000 mg L-1.Saline solution containing Cd and Pb was sprayed on the leaves.Chlorophyll and proline contents were measured after 10 days.Chlorophyll fluorescence of R.pseudoacacia was affected slightly by high concentrations(1000,2000 mg L-1) of Cd and Pb.Chlorophyll a and a/b increased at 1000 and 2000 mg L-1of Cd and proline content of leaves was similar in all treatments of Cd and Pb.Our results indicated that photosynthetic sensitivity of R.pseudoacacia to Cd and Pb contamination was weak.Photosystem II chlorophyll pigments were not damaged by Pb and Cd stress.We conclude that chlorophyll fluorescence along with chlorophyll and proline contents are useful indicators of Cd and Pb stresses in R.pseudoacacia which widely planted in urban polluted regions in Iran.

Increased salinity and groundwater levels lead to degradation of the Robinia pseudoacacia forest in the Yellow River Delta

Forest degradation is a worldwide problem,although its causes vary due to geographical and climatic differences and man-made causes.In recent years,the Robinia pseudoacacia forest in the Yellow River Delta has suffered severe degradation.The causative mechanisms were investigated in the field over two years,and the results show that increased forest degradation was reflected by increased tree mortality,high leaf and soil sodium salt levels and groundwater depth.Average tree diameters decreased,and leaf chlorophyll and soil microbial contents decreased.Redundancy discriminate analysis(RDA)showed that degradation of the forest was correlated positively with soil salt content,but negatively with groundwater depth.Correlation analysis showed that 0.79%–0.95%soil salt content and above 1.20 m groundwater depth caused the death of R.pseudoacacia trees due to localized anthropogenic economic activities,such as rice farming,that disrupted the original water–salt balance.Measures are recommended to prevent further degradation and restore degraded forests.