Evaluation of Nutritional Composition of Two Fonio Ecotypes Grown in Casamance (Sénégal)

In order to better understand the cultural route, biochemical and nutritional composition of two ecotypes of fonio, a study was carried out in village of Tambananing located approximately 7 km from Sédhiou. The objective of studies was to determine nutritional composition of two ecotypes of fonio: the first called momo in short-cycle mandinka (75 - 90 days) and the other called medium-cycle dibong (90 - 110 days). For this, samples of two ecotypes were collected in an experimental field which was split into two equal parts, one sown with the momo ecotype and the other with the dibong ecotype. The nutritional composition (sugars, fats, proteins, minerals, ash, etc.) and the physicochemical properties (pH, humidity, water activity, color, etc.) of fonio’s were determined by appropriate physicochemical methods. The two ecotypes exhibited quite similar physicochemical properties. The levels of biochemical compounds were relatively close with protein contents of 7.05 ± 0.06 mg/100g for the momo ecotype and of 8.02 ± 0.04 mg/100g for the dibong ecotype, in carbohydrates (76.37 ± 1.2 mg/100g for momo and 78.7 ± 1.5 mg/100g for dibong) and in fat (2.92 ± 0.05 mg/100g for momo and 3.14 ± 0.004 mg/100g for dibong). Identical mineral element contents were found except for iron, an element for which the contents were 10.80 ± 0.008 mg/100g for the momo ecotype and 99.59 ± 0.005 mg/100g for the dibong ecotype. Thus, two ecotypes of fonio present a fairly interesting nutritional composition and their consumption deserves to be popularized and could contribute effectively to fight against the problems of malnutrition of certain vulnerable groups.

Physiological Adaptation of Habitat by Ion Distribution in the Leaves of Four Ecotypes of Reed (Phragmites australis)

The ion levels in the epidermal bulliform cells of epidermis, mesophyll cells and cells of the vascular bundle sheath of four ecotypes of reed (Phragmites australis (Cav.) Trin. ex Steud.) were determined by means of X_ray microanalysis. The results indicated that higher K +, Na +, Ca 2+ , Mg 2+ and Cl - were distributed in the vascular bundle sheath cells than in mesophyll cells and epidermal bulliform cells of the swamp ecotype. Higher Ca 2+ was found in the bulliform cells than in mesophyll cells and vascular bundle sheath cells, higher Mg 2+ in the mesophyll cells and higher K +, Na + and Cl - in the vascular bundle sheath cells of the dune ecotype. Higher Na + and Mg 2+ was determined in the mesophyll cells than in the bulliform cells and vascular bundle sheath cells, and higher K +, Ca 2+ and Cl - in the vascular bundle sheath cells of the light salt meadow ecotype. In the heavy salt meadow ecotype, higher Na + and Mg 2+ were accumulated in the bulliform cells than in mesophyll cells and vascular bundle sheath cells, but higher K +, Ca 2+ and Cl - in the mesophyll cells. Furthermore, the distributional conditions of the above five ions in leaf cells of the four ecotypes and their significance in the physiological adaptation of reed to habitat were discussed in detail.

Effects of Different Sowing Dates and Sites on Starch RVA Profile Characteristics of Different Ecotypes of Rice (Oryza sativa, L. japonica)

[Objective] This study aimed to investigate the effects of different sowing dates and sites on starch RVA profile characteristics of different ecotypes of japonica rice. [Method] Five different ecotypes of japonica rice were sown at seven different dates in four rice planting regions in Jiangsu Province to analyze the differences in starch RVA profile parameters among different rice varieties. [Result] Among eight parameters of rice starch RVA profile, peak time exhibited no significant differences among different sites, while other seven parameters varied significantly or extremely significantly among different sites, sowing dates and varieties. Specifically, rice variety exerted the most significant effects on rice starch RVA profile parameters. Starch RVA profile characteristics varied significantly among different ecological conditions but exhibited no significant differences among different latitudes. To be specific, in different sites, peak viscosity （PKV）, hot paste viscosity （HPV） and breakdown viscosity （BDV） demonstrated a descending order of Huai＇an 〉 Suzhou 〉 Lianyungang 〉 Yangzhou. Cool paste viscosity （CPV） and consistence viscosity （CSV） were higher in the north than in the south; specifically, CPV and CSV were significantly higher in Lianyungang and Huai＇an than in Yangzhou and Suzhou. Setback viscosity （SBV） showed an increasing trend with increasing latitude; specifically, SBV was significantly lower in Suzhou than in other three sites. Pasting temperature （PAT） and peak time （PET） changed slightly among different latitudes. With the postponing of sowing date, peak viscosity （PKV）, hot paste viscosity （HPV）, cool paste viscosity （CPV） and peak time （PET） showed a decreasing trend, setback viscosity （SBV） and consistence viscosity （CSV） increased, breakdown viscosity （BDV） increased first and then decreased, whereas pasting temperature （PAT） decreased first and then increased. Furthermore, rice starch RVA profile parameters showed the same variation trend with sowing date in different sites; early sowing within suitable sowing dates could effectively improve the parameters of rice starch RVA profile. However, different parameters exerted different variations among different sites and most parameters were higher in the north than in the south, which indicated that starch RVA profile parameters were significantly affected by sowing date in the north of Jiangsu Province. Among eight starch RVA profile parameters, setback viscosity exhibited the maximum variation coefficient, while peak time exhibited the minimum variation coefficient. Among five rice varieties, Nanjing 46 exhibited the highest peak viscosity and breakdown viscosity and the lowest setback viscosity and consistence viscosity, suggesting that Nanjing 46 had the most appropriate starch RVA profile characteristics and the best cooking and eating quality. Lianjing 4 exhibited relatively high peak viscosity and breakdown viscosity, and relatively low setback viscosity and consistence viscosity, suggesting that Lianjing 4 had good starch RVA profile characteristics. Different sowing dates and sites exerted significant effects on starch RVA profiles of different eco- types of japonica rice. Rice starch RVA profile characteristics varied significantly among different sites but exhibited no significant variations among different latitudes. In addition, starch RVA profile characteristics varied significantly among different sowing dates. Therefore, early sowing of the same variety was conducive to improving starch RVA profile characteristics in appropriate planting regions. [Conclusion] This study provided a theoretical basis for producing high-quality rice and improving the eating quality of rice in Jiangsu Province.

Leaf Micro-Morphology in Two Ecotypes of Ashleaf Maple Adaptated to Different Survival Environments

Through one hundred years of adaptation in China, The Acer negundo Linn. (as hlea f maple), originally grown in North America, has developed morphological charact er istics to cope the severe situation of its habitats. Two ecotypes from different vegetation belts in the ecotone of eastern Inner Mongolia Autonomous Region wer e detected. Although there was no macroscopic difference, contrasting micro-ch a racteristics had been observed between the two sources. The leaves from more dro ught and warmer zone were found with more trichomes, more and smaller stomata, l arger subsidiary cells, thicker palisade and flatter epidermal wax than those of leaves from the more humid and colder zone. Microstructures of the leaves from xeric sources can more effectively reduce leaf temperature and conserving water than those of mesic sources. Intra-species difference of the two ecotypes is th e result of adaptation in different environments. This should be considered when characteristics of foliage are used as characters of species in taxonomy.

Differences in response of desert plants of different ecotypes to climate warming:a case study in Minqin, Northwest China

Globally climates are warming. How do desert plants of different ecotypes respond to the climate change？ This paper studied the differing responses to climate warming shown by desert plants of different ecotypes through analyzing the phenology and meteorological data of 22 desert plant species growing in Minqin Desert Bo- tanical Garden in Northwest China during the period 1974-2009. The results indicate： （1） The temperature in the study area has risen quickly since 1974, and plants＇ growing periods became longer. The spring phenology of mesophytes advanced, and the autumn phenology of xerophytes was delayed; （2） The starting dates of spring phenophase of mesophytes and xerophytes differed significantly and both showed an advancing trend; （3） The spring phenology of mesophytes advanced by more days than that of xerophytes, whereas the autumn phenology of mesophytes was delayed by less days than that of the xerophytes; and （4） Mesophytes are more sensitive than xerophytes to rising temperature in spring and falling temperature in autumn. These findings are of value in plant management and regional introduction of different species.

Control of Leaf Spot Diseases on Ecotypes of Faba Bean (<i>Vicia faba</i>L.) Produced in the Andean Region of Bolivia

The basin of Lake Titicaca is a faba bean-producing microregion of Bolivia where the crop is destined for export. The most commonly cultivated ecotypes “Gigante de Copacabana” and “Usnayo” are affected by diseases that can cause production losses. The aims of the present work were to identify the causal agents of leaf spot affecting these ecotypes, to record disease intensity levels, and to estimate their effect on production. In 2004 and 2005, leaflet, stem and pod samples were taken from faba bean plants with leaf spot growing in the Lake Titicaca area, and from plants in an experimental plot established to determine the effect of five different treatments on production and disease intensity: T1 = Control;T2 = seed treatment with Trichoderma sp. + alternate foliar spraying with benomyl and mancozeb;T3 = seed treatment with fludioxanil/metalaxyl M + alternate foliar spraying with benomyl and mancozeb;T4 = foliar spraying with Trichoderma sp.;T5 = alternate foliar spraying with cymoxanyl and mancozeb-chlorothalonil. Microscopic analysis of the samples revealed the presence of new fungal pathogens for faba beans in Bolivia (Cladosporium sp., and Lepthosphaerulina sp.) as well as emerging fungal pathogens (Botrytis cinerea, B. fabae, Ascochyta fabae, Alternaria sp. and Cercospora sp.). None of the treatments affected the disease progression curve (DPC) for incidence, although effects were seen with respect to disease severity. The seed + foliar treatments (T2 and T3) were more effective at controlling disease than leaf treatments on their own (T4 and T5). Modelling analysis showed faba bean leaf spot disease to be moderately destructive. Compared to chemical treatments, biocontrol with Trichoderma spp. preliminary was found to provide good control of the disease. Losses due to leaf spot disease of 36% were recorded, and a strong correlation detected between yield and disease severity.

Morphometric Traits Differentiation and Phenotypic Diversity of Two Snail Species Ecotypes Archachatina marginata and Achatina fulica in the Western Highlands of Cameroon

This study was conducted from June 2021 to January 2023 to assess the genetic diversity of giant African snails in the western highlands of Cameroon. A total of 652 snails were randomly collected from the wild in three localities in the western highlands (Bafang, Bafoussam, and Santchou). The study revealed significant variations in morphobiometric characteristics both between species and localities. The predominant shell coloration was brownish with yellow zigzag stripes (65%), while the dominant coloration for shell openings was whitish (48%). Regarding foot coloration, both brown with spotted black and black with spotted brown colorations were dominant (29%). The highest recorded live weight of snails (39.33 ± 34) was found in the species Archachatina marginata. In terms of length measurements (in mm), the length of the right and left sides of the shell was higher in the A. fulica species (49.8 ± 19.7 mm and 40.07 ± 18 mm, respectively). Bafang exhibited the highest values for shell length (56 ± 11 mm) and shell width (46.52 ± 11.46 mm). A. fulica recorded the highest shell length (81.5 ± 27 mm), while A. marginata recorded the highest shell width (49.6 ± 12.1 mm), with the highest values observed in A. fulica from fulica having a slightly higher aperture width value (30 ± 10 mm) compared to A. marginata, while A. marginata had the highest value for aperture length measurement (54.5 ± 12 mm). A. fulica also exhibited the highest values for the length from apex to the first whorl and the length from left to right of the first whorl (43.2 ± 18 mm and 39 ± 19.8 mm, respectively). Strong and positive correlations were observed between the live weight of snails and body measurements regardless of species, except for the number of whorls, which showed very weak or negative correlations with other body measurements. The results of Hierarchical Cluster Analysis (HCA) revealed three distinct snail population types. These findings provide valuable insights into the phenotypic diversity of edible land snails in the western highlands of Cameroon and can be considered in improvement and conservation programs aimed at enhancing snail meat yield.

Seasonal changes of endogenous ABA and cytokinins in environmental adaptation of different ecotypes of reed plants

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Intraspecific diversity: adaptive differentiation of Picea mongolica W. D. Xu ecotypes

Picea mongolica W. D. Xu is an endemic and endangered species which is only found in semi-arid areas of northern China. It has been widely used as an afforestation tree in the establishment of the Three-North Shelterbelt System for its adaptation to arid soils and as a virescent tree in urban gardens and streets for its beautiful shape. Due to different microenvironments, P. mongolica populations may differentiate into many ecological groups with different adaptive abilities. Long-term adaptation to a dry environment makes P. mongolica differentiate into different ecotypes. Typical ecotypes are P. mongolica f. purpurea （Fp）, P. mongolica f. rubra （Fr） and P. mongolica f. viridis （Fv）. Our results show that cone size is clearly not uniform among different ecotypes; the largest cones are found in the Fv ecotype and the smallest in Fp. There were also distinct differences between these ecotypes in terms of height and length of squama. At the molecular level, the zymograms of peroxidase and lipase prove the existence of different ecotypes in P. mongolica. The results are useful for investigating and managing this rare spruce species in China.

Yellowing of disease? Or differentiating for adaptation? Study on Cinnamomum camphora ecotypes

Cinnamomum camphora （L.） Presl is an evergreen broad-leaved tree of the Lauraceae family, widely distributed in the sub-tropical areas in the south of China and used as a virescent tree in urban gardens and streets in Shanghai for its beautiful shape and intensive stress-resistance. However, yellowing of C camphora in recent years casts doubt about its significance. We believe the green-leaved and yellow-leaved C camphora might be two different ecotypes, and tentatively refer to the green-leaved C camphora as C camphora f. viridis f. nov （CCV） and the yellow-leaved as C camphora f.flavus f. nov （CCF）. We studied their differences and arrived at the following conclusions： 1） compared with CCF, the area of lamina of CCV is significantly larger and the amount of chlorophyll （Chl） significantly higher; 2） the lamina and palisade tissues of CCV are significantly thicker than those of CCF, but its cuticle is significantly thinner; 3） the shape of the stomata of CCV is different from that of the CCF; the stomatal density and stomatal index of CCV are significantly lower than those of CCF. These results show that C camphora might evolve adaptive dif- ferentiation in some aspects which can be used in virescence in urban streets and gardens.

The adaptive significance of differences of root morphology, anatomy and physiology from three ecotypes of reed(Phragmites communis Trin.)

Reeds are widely distributed in drought and high salt conditions of northwestern China. Leaf epidermal micromorphology, anatomy, chloroplast ultrastructure and physio-chemical characteristics due to long-term adaptation in the natural habitats of common reed （Phragmites communis Trin.） contrasted considerably among three different ecotypes： dune reed （DR）, Gobi salt reed （GSR） and swamp reed （SR）. The main objective of the present study is to determine the adapting characteristics of morphology, anatomy and physiological responses of thin roots in DR, GSR and SR. The results show that root length density was higher in SR and few root hairs were observed in DR. Cross-section anatomical features show that each ecotype has an endodermis and exodermis, while cortex thickness and proportion of root cortical aerenchyma and stele in root structure varied among the three ecotypes. The stele and xylem share a larger area in DR compared to GSR and SR. GSR has a large proportion of the cortex with radialized distribution of aerenchyma cells spacing, and the cortex has a peripheral, mechanically stiff ring in the exodermis. SEM and TEM microscope images show that GSR has a scle- renchyma ring with high lignification in the exodermis. The physio-chemical parameters show that GSR had a higher level of stress tolerance than DR. These findings indicate that developed water-absorbing tissues were largely distributed in the root structure of DR, and a main framework with supporting function spacing with aerenchyma was dominant in GSR in the long term adaptation to their natural habitats, respectively.

Comparative Analyses of Stomatal Size and Density among Ecotypes of <i>Aster hispidus</i>(Asteraceae)

To determine the size and the density of stomata among different environments, we conducted anatomical analyses using Aster hispidus var. hispidus (open field), As. hispidus var. leptocladus (serpentine soil), and As. hispidus var. insularis (coastal). The stomatal size was not significantly different among these ecotypes but the density of stomata in the serpentine and coastal ecotypes was significantly lower than that of As. hispidus var. hispidus, which suggests that these ecotypes have experienced selection that reduced the density of stomata for adaptation to the dry conditions of serpentine and coastal areas.

Environmental conditions and genetic differentiation:what drives the divergence of coexisting Leymus chinensis ecotypes in a large-scale longitudinal gradient?

Aims The two coexisting Leymus chinensis ecotypes exhibit remarkable divergences in adaptive strategies under drought and salinity in semi-humid meadows and semi-arid steppes.In order to detect the major genetic and environmental factors dominating the intraspecific phenotype variations and ecotype formation,the questions regarding the two distinct phenotypic forms(ecotypes)in L.chin-ensis were addressed:(i)did environments drive the L.chinensis ecotype formation?(ii)was there a molecular basis for the morphological divergence between the two ecotypes?(iii)which driving force dominated the intraspecies divergence,divergent natural selection,genetic drift or stabilizing selection?Methods We applied a series experiments on demographical,morphological and physiological traits of two Leymus chinensis ecotypes with gray green(GG)and yellow green(YG)leaf color in nine wild sites along a longitudinal gradient from 114°to 124°E in northeast China.The environmental data including mean annual precipitation,mean annual temperature,elevation and soil properties were collected.We compared the differences of morphological,physiological and genetic differentiations between the two ecotypes.Important FindingsThe GG type exhibited stronger fitness than YG type from the population densities,morphological traits(e.g.shoot height,leaf area,leaf and seed weights et al.),leaf mass per area(LMA)and physiological traits[relative water content(RWC),proline,soluble sugar contents].Most of above phenotypes(e.g.total shoot densities,spike length et al.)were significantly correlated with mean annual precipitation,mean annual temperature and soil water content(SWC),rarely a correlated with soil pH and soil nutrient.Transplanted populations showed convergence trend by their leaf chlorophyll contents and osmotic adjustments(proline and soluble sugar contents)in the greenhouse,but still exhibited their divergences between two ecotypes in the outdoor transplantation,suggesting that whether L.chinensis ecotype differentiated could be largely affected by the environmental conditions.Furthermore,by the comparison result of quantitative genetic variation(Q_(ST))values from phenotypes with theoretical neutral genetic differentiation(F_(ST)),differentiation in phenotypic traits greatly surpassed neutral predictions,implying that directional natural selection played a crucial role in L.chinen-sis ecotype differentiation.In addition,microsatellite analysis from Neighbor-joining tree and Bayesian assignment generated into two groups according to ecotypes,indicating molecular genetic differentiation also propelled the two ecotypes divergence.We conclude that L.chinensis population variations were driven by combing divergent natural selection(precipitation,temperature and SWCs)along the large-scale gradient and significantly intrinsic genetic differentiation.

New insights into diet breadth of polyphagous and oligophagous aphids on two Arabidopsis ecotypes

We investigated whether plant ecotype might affect aphid performance and behavioi. The probing behaviors of the polyphagous aphid Myzus persicae and the oligophagous aphid Brevicoryne brassicae on two ecotypes of Arabidopsis thaliana, WS and Col-0 were recorded using the direct current electrical penetration graph method (DC-EPG). Myzus persicae displayed a significant preference for the WS ecotype but was not greatly disturbed on Col-0, while B. brassicae discriminated between the two A. thaliana ecotypes, feeding less on WS than on Col-0. A Principal Component Analysis of aphid probing behavior data recorded on Col-0 and WS ecotypes showed that the one of M. persicae was positively correlated with the phloem ingestion phases while the one of B. brassicae was more related to nonfeeding phase. The survival of the aphid species was followed during early larval stages on the two ecotypes and a significantly higher mortality was observed of B. brassicae neonates compared to M. persicae. Both reared on WS. Moreover, transcriptomic analysis of non infested plant leaves from both ecotypes was monitored and underlined constitutive differences between Col-0 and WS gene expression that might explain the different aphid behaviors. Among a unigene set comprising 39 042 sequences for A. thaliana, 6% were differently expressed affecting, for example, the secondary metabolites and cell wall pathways: two third upregulated in WS and one third upregulated in Col-0. Thus, the "ecotype” variable should be taken into account when setting up a plant-insect experimental research.

Effects of Silicon at Different Concentrations on Morphology and Photosynthetic Physiological Mechanism of Japonica Rice

[Objective] The aim was to explore effects of silicon at different concentrations on morphology and photosynthetic physiological mechanism of japonica rice. [Method] Seedlings of japonica rice were treated with silicon at different concentrations （0, 30, 80, 130 and 180 mg/L of sodium silicate）; silicon contents were measured with Molybdenum blue spectrophotometric method in root, stem and leaf; plant height, root length and number in different treatment groups were measured with tools; chlorophyll a and b, and a/b in leaf and stem of rice in different groups were measured. [Result] Silicon contents in vegetative organs were as follows： stem〉leaf〉 root; when silicon was 80 mg/L, japonica ecotype was shortest; when silicon was 30 mg/L, root length of the rice was shortest and root number was least; when silicon was 30 mg/L, contents of chlorophyll a and b were highest and chlorophyll a/b achieved the peak when silicon was 80 mg/L. [Conclusion] Silicon at proper concen- tration would improve lodging-resistance and efficiency of photosynthesis, further enhancing yield of japonica rice.

Genetic Diversity of Cameroon Native Goat Populations Revealed by Caprine Microsatellites

A total of seventeen caprine microsatellite markers were used on 169 goats to investigate genetic diversity of eight Cameroon native goat populations and to assess genetic differentiation with the East African small goat. All microsatellites showed a high polymorphic content （PIC） of more than 0.5 in almost all ecotypes. These microsatellite markers were useful for native goat ecotypes variability assessment. Expected heterozygosity of all ecotypes was above 0.5, varying from 0.2 to 0.7. Only goats from Eastern rainforest ecotype deviated from Hardy-Weinberg equilibrium test （P 〉 0.001）. Although geographic distribution was a good indication of differentiation, there appeared a tendency of genetic exchange between various ecotypes in Cameroon native goats.

Genetic Diversity of Indigenous Chicken (Gallus Gallus domesticus) from Ecozones of Egypt and Kingdom of Saudi Arabia

Genetic diversity of two chicken ecotypes from Ismailia-Egypt (ISM) and Taif-Saudi Arabia (TA) was evaluated using 39 microsatellites. DNA was extracted from blood of 25 chickens/ecotype. The number of alleles was 157 and 138, the number of alleles/locus averaged 4.2±2.2 and 3.6±1.6, and the highest number of private alleles was 9 and 5 for ISM and TA, respectively. Percentage of shared alleles between the two ecotypes was 45%. This panel of markers is reasonably informative as the mean polymorphic information content for ISM and TA was 0.47±0.21, and 0.41±0.2. Similar average of observed heterozygosity was attained for both ecotypes. Conversely, averages of expected heterozygosity differed between two ecotypes, 0.52±0.23 vs. 0.45±0.21 for ISM and TA. 8 and 12 loci have significantly deviated from HWE of ISM and TA. Estimate of genetic distance was 0.2 and FST index was 0.29. Results showed only 6% of genetic diversity is shared between these two ecotypes.

Experiment on Organic Ecotype Soilless Culture of Vegetables

A suitable substrate formula for vegetable cultivation was selected through experimenting on the culture substrate for organic ecotype soilless culture of vegetables, and organic matter content of the substrate was 294% as name that of soil, while the content of N, P and K were 328%, 279% and 192% that of the soil, respectively. Vegetable yield with this substrate was 157%-228% that with the soil.

Revealing Toxin Signatures in Cyanobacteria: Report of Genes Involved in Cylindrospermopsin Synthesis from Saxitoxin-Producing <i>Cylindrospermopsis raciborskii</i>

Cyanotoxins are distinctive molecules in Cyanobacteria whose evolutionary origin, radiation and ecological role are still controversial. The cyanobacterium Cylindrospermopsis raciborskii is alternately capable of producing two types of potent toxins, cylindrospermopsin (CYN) or saxitoxin and analogues (SAX). It has been proposed that this species spread to all continents early in its evolutionary history and biogeographical differences in toxin production are found between populations. Most reports indicate that American strains are able to produce SAX but not CYN, while Australian strains are described to produce CYN but not SAX. Here we describe the presence of three genes belonging to the cylindrospermopsin cluster (cyr), cyrA, cyrB and cyrC, in two SAX producing South American C. raciborskii strains, MVCC14 and MVCC19, which due to their differences in morphology, growth preferences, SAX production and genetic context are defined as different ecotypes. No CYN production was detected in either strain (by ELISA) after growth under nitrogen replete or nitrogen-free nutrient conditions. Phylogenetic analyses of cyrA, cyrB and cyrC partial sequences from both strains showed high similarity (>99%) with CYN genes belonging to C. raciborskii strains from Australia and Germany and to Aphanizomenon strains. This is the first report of the presence of cyr genes in strains known to produce only SAX.

Ecotype and Regional Division of Afforestation Plants in China

The selection of afforestation plants,which is based on the ecotype of afforestatioin plant,is the key of plant engineering. There is not final verdict yet on the standard of ecotype of afforestation plant. According to the presentational feature （regional distribution,Climatic indicator）,ecotype （climatoecological type,edaphic ecotype and biota ecotype） and genetic association of afforestation plant,combined with the experience in the greening practice,the afforesting nursery stock （Arbor and Shrub ） is divided into five ecotypes while the herbaceous plant are divided into three ecotypes.