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1.
The allelopathic potential of Mikania micrantha H.B.K. to affect the seed germination and seedling growth of Coix lacryma‐jobi L. was investigated. Water‐soluble allelopathic substances were found in the water extracts of M. micrantha. The effect of the water extracts on the seed germination and seedling growth of C. lacryma‐jobi was concentration‐dependent. The water extracts from the different plant parts (leaf, stem, and root) of M. micrantha differed in their effect on the germination and seedling growth of C. lacryma‐jobi, with the effect of the leaf extract being the least inhibitory. The malondialdehyde (MDA) content in the C. lacryma‐jobi seedlings increased by 64%, 45%, and 52% of the control with increasing concentrations of the extracts of the root, stem, and leaf (80, 400, and 400 g L?1, respectively). The extract from the M. micrantha roots significantly increased the catalase (CAT) activity of the C. lacryma‐jobi seedlings (48% and 54% of the control at the concentrations of 20 g L?1 and 80 g L?1, respectively). The extracts from the leaves and stems at low concentrations increased the CAT activity, but at high concentrations, the extracts decreased the CAT activity. The extracts from the roots, stems, and leaves at concentrations of 80, 400, and 400 g L?1 also significantly decreased the peroxidase (POD) activity of the C. lacryma‐jobi seedlings to 27%, 52%, and 34% of the control, respectively. These results indicate that the water extracts of M. micrantha could inhibit the seed germination and seedling growth of C. lacryma‐jobi through the regulation of anti‐oxidase activity, such as POD and CAT in the cells. The growth inhibition of the C. lacryma‐jobi seedlings is probably related to injury after oxidization of the cell membranes with the increase of MDA content.  相似文献   

2.
Cuscuta species (dodders) are widespread stem holoparasites that depend on host plants for their entire mineral and water and most carbohydrate requirements. Dodders negatively affect host photosynthesis but precise information on their impact on hosts in the presence of environmental stress factors (i.e. drought) is little known. In a pot experiment, the leaf traits, gas exchange and chlorophyll a fluorescence of the invasive climber, Mikania micrantha, parasitized by Cuscuta australis, were investigated in order to study variations of host photosynthesis in response to parasitism and drought. The results showed that the concomitant presence of C. australis infection and drought significantly impacted the leaf traits (i.e. increased leaf dry mass content), gas exchange (i.e. decreased stomatal conductance and transpiration rates and increased water‐use efficiency) and quantum yield of chlorophyll a fluorescence of M. micrantha. The presence of a single stress factor (C. australis infection or drought), however, only significantly affected the leaf traits and gas exchange of M. micrantha. These results suggested that the combined additive effects of C. australis parasitism and drought significantly suppressed the photosynthesis of M. micrantha in relation to both stomatal and non‐stomatal limitation of host photosynthesis. This study provides insights into Cuscuta–host interactions under drought conditions in the tropics.  相似文献   

3.
Crops limit light for photosynthesis and growth of weeds. We studied the effect of reduced light on performance of six weed species [one invasive species (Amsinckia micrantha), three common species (Veronica persica, Capsella bursa‐pastoris, Viola arvensis) and two less common weeds (Anagallis arvensis and Scleranthus annuus)]. In two glasshouse experiments, six light levels were achieved aiming at 0%, 20%, 50%, 80%, 90% and 95% reduction of light and corresponding with daily light integrals (DLI) of 12.4, 9.63, 7.13, 2.74, 0.95 and 0.69 mol m?2 day?1 in experiment 1 and 21.2, 18.0, 10.7, 3.71, 1.64 and 1.20 mol m?2 day?1 in experiment 2. The number of leaves was strictly controlled by DLI. Chlorophyll content index, maximum photochemical efficiency of photosystem II (Fv/Fm), stomatal conductance, flowering and dry matter were strongly reduced when DLI was reduced to 0.69–3.71 mol m?2 day?1 for all species. Threshold DLI for flowering was ca. 3.71 mol m?2 day?1 for S. annuus, V. arvensis, A. arvensis and V. persica, while C. bursa‐pastoris deviated by flowering at DLI of 0.95 mol m?2 day?1. This may explain why C. bursa‐pastoris is common in the seedbank of Danish arable soils in spite of intensive farming with well‐fertilised and dense crops.  相似文献   

4.
Increasingly, weeds have been taking on global distributions. With the proliferation of invasive weeds has come the challenge of managing these species over broad geographical regions, with diverse habitats and political jurisdictions. Here, we review the management of Mikania micrantha Kunth (Asteraceae; mile‐a‐minute) throughout its invaded range, extending through most of the Pacific islands and southern and south‐east Asia. Context matters when determining the best course of action for managing M. micrantha, as it has invaded a large variety of agricultural and natural systems. In Queensland, Australia and Florida, USA, M. micrantha has been targeted in relatively successful eradication campaigns, highlighting the importance of early detection and rapid response methods, while elsewhere in its invaded range, populations are either still increasing or showing limited signs of decline. An inter‐regional approach to research and management should incorporate successful management strategies employed throughout the invaded range including, but not limited to, chemical and cultural control practices, manual and mechanical control, classical biological control using the rust fungus Puccinia spegazzinii, plant–plant competition and integrated approaches utilising two or more control methods concurrently. Additional knowledge of M. micrantha genetics is required to determine if management approaches could be fine‐tuned for particular populations. Countries bordering the Mekong River formed a network in 2011 to co‐ordinate the management of invasive species such as M. micrantha. Expanding such a collaborative approach to other regions could further reduce populations of M. micrantha and limit its spread.  相似文献   

5.
Atrazine carryover often limits growers to production of atrazine-tolerant crops the year following application, and allows the increase of triazine-tolerant weed species such as Panicum miliaceum L. (wild proso millet). Tiriazine-resistant Brassica napus L. cv. ‘Triton’ (oilseed rape) was tested to characterize the nature of interspecific interference with P. miliaceum. In a greenhouse study, atrazine at 2.2 kg ha?1 depressed oilseed rape fruit (siliqua) number and fruit dry weight, and delayed flowering, but did not significantly affect height or weight of shoots, Oilseed rape fruit weight was reduced at 200 P. miliaceum plants m?2. fruit number and shoot weight were inhibited at 400 weeds m?2. and height was reduced and flowering delayed at 600 weeds m?2. Number and weight of fruits were reduced by one-third after 8 weeks of interference as compared to oilseed rape grown with the weed for 4 weeks. Oilseed rape height was reduced by 29% and shoot weight by 55% by 600 weeds m?2 and 2–2 kg ha?1 atrazine, while fruit number and weight were reduced by 72%. Oilseed rape shoot weight was reduced by 74% by 600 weeds m?2 for 12 weeks of interference, while fruit number and weight were reduced by 85% and 82%. respectively. In a field study, fluazifop reduced early season P. miliaceum cover by 72%, but did not increase oilseed rape cover. Mid-season P. miliaceum shoot weight was decreased by 97% by fluazifop and oilseed rape shoot weight was increased by 34%. P. miliaceum control increased oilseed rape biomass by 38% at 89 days, but biomass of oilseed rape sown at 11.2 kg ha?1 with 2.2 kg atrazine ha?1 was not decreased by P. miliaceum interference at 89 days.  相似文献   

6.
Mikania micrantha H.B.K., one of the top 10 worst weeds in the world, is now spreading quickly in southern China. Disturbance can fragment and spread the stolons of M. micrantha. A greenhouse experiment was conducted in order to assess the regeneration capacity of single‐node fragments with varying stolon thickness (diameters of 3.01, 2.49 and 1.96 mm), internode lengths (2 and 8 cm) and leaf presence status (with and without leaves). The results indicated that an increasing stolon thickness, internode length and the presence of leaves all increased the survival rate of the clonal fragments. An increasing stolon thickness, internode length and the presence of leaves also increased the growth of the clonal fragments and the presence of leaves exhibited the strongest effect. An increasing internode length and the presence of leaves also reduced the amount of time that was needed for emergence, while the effect of the stolon thickness was not significant. None of the effects of the interactions was significant, although the interaction between the stolon thickness and the internode length was nearly significant for fragment survival. These results suggest that M. micrantha has developed a strategy to cope with disturbance by storing reserves in the stolons and leaves, which could increase its regeneration capacity after fragmentation. Currently, the management of M. micrantha (such as manual or mechanical control) should avoid the generation of the small clonal fragments of M. micrantha, while repeated control with short time intervals is necessary in order to prevent reinvasion from the stolon fragments.  相似文献   

7.
Self-incompatibility in Mikania micrantha in South China   总被引：1，自引：0，他引：1  
Mikania micrantha is a successful invasive weed in many parts of the world, but we do not know how its mating system may have contributed to this. Therefore, its mating system was studied in an open M. micrantha population during the flowering seasons of 2004 and 2005. Pollen/ovule ratio was determined and pollination treatments were applied on entire inflorescences to estimate the seed/ovule ratio. The pollen/ovule ratio of M. micrantha was 4008, and seed/ovule ratio was 0.56 for open pollination and 0.0034 and 0.0038 for wind pollination and selfing respectively. These data indicate that the weed is self‐incompatible and needs insect pollination.  相似文献   

8.
Endozoochory is known as an important mechanism for the spread of weeds. We carried out experiments to assess the fate of seeds of several weed species (Convolvulus arvensis, Cuscuta campestris, Rumex crispus, Hordeum spontaneum and Sorghum halepense) after passing through the gut of sheep and goat. Eighteen animals of both sheep and goat received diet mixed with seeds of the weed species or control with only wheat bran (five weed species + control × three replications). Results showed that a higher proportion of seeds were missing after passage through the sheep gut than in goats. In goats, a greater proportion of seeds were dead after passage, but the number of seeds collected from dung was also greater. Weed species differed, with the highest seed recovery and viability in Cuscuta campestris. Based on time of seed passages through the animal gut estimated for the different weed species, we recommend that sheep should be kept in a corral for 96 hr to minimise seed transportation via their faeces. For goats, if R. crispus and C. arvensis seeds could be excluded from the diet, then maintaining them for 96 hr in an animal stall would ensure little seed transportation via dung, but we found R. crispus and C. arvensis seeds to be present and viable in goat dung even 120 hr after feeding. Very large numbers of viable seeds can be found in goat and sheep dung, so the use of rotted manure is highly recommended to avoid transportation of viable seeds via manure fertilisers.  相似文献   

9.
The response of Cuscuta campestris Yuncker, a non‐specific above‐ground holoparasite, to amino acid biosynthesis inhibitor (AABI) herbicides, was compared with other resistant and sensitive plants in dose–response assays carried out in Petri dishes. Cuscuta campestris was found to be much more resistant to all AABI herbicides tested. The I50 value of C. campestris growth inhibition by glyphosate was eightfold higher than that of transgenic, glyphosate‐resistant cotton (RR‐cotton). The I50 value for C. campestris shoot growth inhibition by sulfometuron was above 500 μM, whereas that of sorghum roots was only 0.004 μM. Cuscuta campestris exposed to glyphosate gradually accumulated shikimate, confirming herbicide penetration into the parasite and interaction with an active form of the target enzyme of the herbicide, 5‐enolpyruvylshikimate‐3‐phosphate synthase. More than half of the C. campestris plants associated with transgenic, glyphosate‐resistant sugarbeet (RR‐sugarbeet) treated with glyphosate or with transgenic, sulfometuron‐resistant tomato (SuR‐tomato) treated with sulfometuron recovered and resumed regular growth 20–30 days after treatment. New healthy stems developed, followed by normal flowering and seed setting. The results of the current study demonstrate the unique capacity of C. campestris to tolerate high rates of AABI. The mechanism of this phenomenon is yet to be elucidated.  相似文献   

10.
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11.
The benefits of conservation agriculture (CA) and associated technologies are not equal for all agro ecosystems. This study used a field experiment to examine winter-wheat yield and weeds under conservational and conventional systems in the central region of Spain. The three tillage treatments were conventional tillage (CT), minimum tillage (MT) and no-tillage (NT). The climatic conditions influenced wheat yield, yield components, soil water content and weeds. When the autumn-winter rainfall was abundant and constant (69.7% of annual rainfall), wheat grain yield (4465?kg?ha?1) and yield components (3897?kg?ha?1 of straw biomass and 584.5 ear m?2) were highest. Wheat grain yield was highest with NT: 3549.9?kg?ha?1 (compared to MT: 2955.1?kg?ha?1 and CT: 2950.3?kg?ha?1) and ear number per m2 was significantly lower with MT (332 no ear m?2, compared to 426 and 411.6?ear?m?2 in CT and NT-systems respectively). Soil water content, at earing stage, was the highest in NT (27.36% of soil moisture) while MT showed the lowest content (11.83% of soil moisture). The higher weed measurements (means of 2.557 plants m?2; 1.443 species m?2 and 2.536 g m?2) was with higher annual rainfall (488?mm). Throughout the experiment it was the dominant presence, in MT-wheat plots, of Lolium rigidum Gaudin (with means from 4.87 to 7.71 plants m?2), which reduced the ear number per m2. Our study revealed that in the short term, under semi-arid conditions, only the adoption of NT system (rather than MT) showed economic benefits.  相似文献   

12.
The effects of a range of herbicide doses on crop–multiple weed competition were investigated. Competitivity of Galium aparine was approximately six times greater than that of Matricaria perforata with no herbicide treatment. Competitivities of both weeds decreased with increasing herbicide dose, being well described by the standard dose–response curve with the competitivity of M. perforata being more sensitive than that of G. aparine to a herbicide mixture, metsulfuron‐methyl and fluroxypyr. A combined model was then developed by incorporating the standard dose–response curve into the multivariate rectangular hyperbola competition model to describe the effects of multiple infestation of G. aparine and M. perforata and the herbicide mixture on crop yield. The model developed in this study was used to predict crop yield and to estimate the herbicide dose required to restrict crop yield loss caused by weeds to an acceptable level. At the acceptable yield loss of 5% and the weed combination of 120 M. perforata plants m?2 and 20 G. aparine plants m?2, the model recommends a mixture of 1.2 g a.i. ha?1 of metsulfuron‐methyl and 120 g a.i. ha?1 of fluroxypyr.  相似文献   

13.
The effects of sub‐lethal dose of herbicide and nitrogen fertilizer on crop–weed competition were investigated. Biomass increases of winter wheat and a model weed, Brassica napus, at no‐herbicide treatment with increasing nitrogen were successfully described by the inverse quadratic model and the linear model respectively. Increases in weed competitivity (β0) of the rectangular hyperbola and parameter B in the dose–response curve for weed biomass, with increasing nitrogen were also successfully described by the exponential model. New models were developed by incorporating inverse quadratic and exponential models into the combined rectangular hyperbola with the standard dose–response curve for winter wheat biomass yield and the combined standard dose—response model with the rectangular hyperbola for weed biomass, to describe the complex effects of herbicide and nitrogen on crop–weed competition. The models developed were used to predict crop yield and weed biomass and to estimate the herbicide doses required to restrict crop yield loss caused by weeds and weed biomass production to an acceptable level at a range of nitrogen levels. The model for crop yield was further modified to estimate the herbicide dose and nitrogen level to achieve a target crop biomass yield. For the target crop biomass yield of 1200 g m?2 with an infestation of 100 B. napus plants m?2, the model recommended various options for nitrogen and herbicide combinations: 140 and 2.9, 180 and 0.9 and 360 kg ha?1 and 1.7 g a.i. ha?1 of nitrogen and metsulfuron‐methyl respectively.  相似文献   

14.
Investigation of the germination of six tropical arable weeds With the six tropical arable weeds studied, Ageratum conyzoides, Blechum brownei, Crassocephalum crepidioides, Mikania micrantha, Paspalum conjugatum and P. paniculatum, the lowest temperatures at which germination occurred were in the range 10–15(20)°C, the highest up to 40°C, with the optimum between 20°C and 35°C. Ageratum conyzoides and C. crepidioides had lower limits of germination temperature than the other species, which explains their comparatively greater incidence at high altitudes. The germination temperatures of both representative temperate species, Alopecurus myosuroides and Chenopodium album were 5 (minimum), 15–25 (optimum) and 40°C (maximum). The germination of A. conyzoides, C. crepidioides and M. micrantha was reduced by an osmotic potential of - 1 bar. At -4·7 bar only P. paniculatum of the tropical species germinated to a small extent whilst Al. myosuroides and Ch. album were not affected. After storage for a year in dry conditions all six tropical species only germinated when exposed to light. After 20 months, C. crepidioides and P. paniculatum would also do so in the dark.  相似文献   

15.
Sustainable cropping systems based on low inputs have received much attention, even if they may lead to the establishment of a competitive weed flora. This study, conducted from 2011 to 2014 in a Mediterranean environment, evaluated the changes in weed community composition in two cropping systems [conventional (CONV ) and organic (ORG )] with different soil tillage [inversion tillage (IT ) and non‐inversion tillage (NoIT )] in a wheat–tomato–chickpea rotation that began in 2000. The treatments were replicated three times according to a randomised complete block design. The organic system was managed according to EU regulations. Inversion tillage consisted of mouldboard ploughing to a depth of 30 cm, while NoIT consisted of subsoiling to a depth of 20 cm. Weed control was based on herbicide application in CONV and mechanical weeding in ORG . The organic non‐inversion system showed the highest weed biomass (134, 128 and 195 g dry matter (DM ) m?2 in wheat, tomato and chickpea, respectively) and weed density (66, 77 and 76 plants m?2 in wheat, tomato and chickpea, respectively), as well as community richness. However, ORG always increased weed diversity, even if annual dicotyledon species were abundant in ORG ‐IT and perennial dicotyledon species in ORG ‐NoIT . The conventional system enhanced the relative frequency of both annual (CONV ‐IT ) and perennial (CONV ‐NoIT ) grasses. There was a negative correlation between density of perennial weeds and crop yield (r 2 = 0.24, P  <  0.001). Therefore, in the Mediterranean environment, combining organic practices with non‐inversion tillage could lead to the establishment of perennial weeds that are difficult to control, thus requiring specific weed management practices.  相似文献   

16.
Helopeltis theivora Waterhouse (Heteroptera: Miridae) is a major sucking insect pest of tea (Camellia sinensis) which feeds on a wide variety of alternative host plants. Feeding biology and fitness traits of H. theivora, on two alternative host plants, viz., Mikania micrantha (Asteraceae) and Psidium guajava (Myrtaceae), besides C. sinensis (Theaceae), were studied along with corresponding levels of xenobiotic defense enzymes. C. sinensis is the preferred host of H. theivora. The development time of H. theivora is significantly shorter on C. sinensis (13.3?±?0.16?days) than on the two other hosts, M. micrantha (14.2?±?0.22?days) and P. guajava (14.7?±?0.23?days). Similarly, the fecundity (C. sinensis: 172.6?±?4.5 eggs/female, M. micrantha: 128.6?±?4.4 eggs/female, P. guajava: 118.7?±?3.3 eggs/female), oviposition period (C. sinensis: 24.1?±?0.7?days, M. micrantha: 22.5?±?0.6?days, P. guajava: 21.7?±?0.8?days) and hatchability (C. sinensis: 80.9?±?1.9%, M. micrantha: 69.4?±?1.6%, P. guajava: 64.1?±?1.7%) are recorded to be significantly higher on C. sinensis. The age at reproductive maturity and egg incubation periods were lower on C. sinensis than on the two other host plants. Host-based variation in H. theivora fitness traits is interpreted in light of differential activity of three principal xenobiotic detoxifying enzymes, the general esterases (GEs), glutathione S-transferases (GSTs) and cytochrome P450 monooxygenases (CYPs). The activities of these enzymes in H. theivora were significantly enhanced when the insect fed on M. micrantha and P. guajava as compared with on C. sinensis.  相似文献   

17.
Stratospheric ozone (O3) depletion has led to increased terrestrial ultraviolet‐B (UV‐B) radiation (290–320 nm). Leaves exposed to this radiation produce UV‐absorbing compounds in the epidermal cells, which protect plants from UV‐B damage. To determine the role of UV‐absorbing compounds in the UV‐B sensitivity of weeds (common chickweed (Stellaria media), downy brome (Bromus tectorum), green smartweed (Polygonum scabrum), redroot pigweed (Amaranthus retroflexus), spotted cat’s‐ear (Hypochoeris radicata), and stork’s‐bill (Erodium cicutarium)) seedlings were exposed to 0, 4 (field ambient), 7 (18% O3 depletion) and 11 (37% O3 depletion) kJ m?2 d?1 of biologically effective UV‐B radiation in a greenhouse. Ultraviolet‐absorbing compounds were extracted from the second true‐leaf (0.5 cm2 samples) with methanol : distilled water : HCl (79 : 20 : 1) in an 85°C water bath for 15 min, and the absorbance of the extracts measured at 300 nm. The shoot dry biomass was recorded to determine the susceptibility to UV‐B radiation. Common chickweed was the most sensitive and green smartweed the least sensitive weed to UV‐B radiation. The latter accumulated more UV‐absorbing compounds and this accumulation occurred earlier compared with common chickweed. As UV‐BBE radiation levels increased from 0 to 11 kJ m?2 d?1, the green smartweed shoot biomass did not decline. However, the biomass of all five susceptible species declined despite an increase in the UV‐absorbing compounds in response to increased UV‐B radiation. Therefore, formation of a ‘UV‐screen’ in these species is not sufficient to fully prevent UV‐B damage. When the concentration of UV‐absorbing compounds in the six species was plotted against their susceptibility to UV‐B radiation, no relationship was observed. Thus, while the accumulation of UV‐absorbing compounds may be a major factor in the protection of certain species against UV‐B radiation and may offer some degree of defence in other species, it does not explain UV‐B susceptibility differences in weedy species in general.  相似文献   

18.
BACKGROUND: Herbicide‐resistant crop technology could provide new management strategies for the control of parasitic plants. Three herbicide‐resistant oilseed rape (Brassica napus L.) genotypes were used to examine the response of attached Cuscuta campestris Yuncker to glyphosate, imazamox and glufosinate. Cuscata campestris was allowed to establish on all oilseed rape genotypes before herbicides were applied. RESULTS: Unattached seedlings of C. campestris, C. subinclusa Durand & Hilg. and C. gronovii Willd. were resistant to imazamox and glyphosate and sensitive to glufosinate, indicating that resistance initially discovered in C. campestris is universal to all Cuscuta species. Glufosinate applied to C. campestris attached to glufosinate‐resistant oilseed rape had little impact on the parasite, while imazamox completely inhibited C. campestris growth on the imidazolinone‐resistant host. The growth of C. campestris on glyphosate‐resistant host was initially inhibited by glyphosate, but the parasite recovered and resumed growth within 3–4 weeks. CONCLUSION: The ability of C. campestris to recover was related to the quality of interaction between the host and parasite and to the resistance mechanism of the host. The parasite was less likely to recover when it had low compatibility with the host, indicating that parasite‐resistant crops coupled with herbicide resistance could be highly effective in controlling Cuscuta. Published 2009 by John Wiley & Sons, Ltd.  相似文献   

19.
Although preference for NH4+, NO3? or a combination of the two often differs among species, we know little about the responses of invasive plants to different inorganic N forms. Furthermore, many studies have suggested that an increase in N availability may facilitate further invasions. However, most of these studies predicted the positive feedback without considering the preference for N forms of invasive plants. Therefore, we cultivated four common invasive species (Mikania micrantha, Ipomoea cairica, Wedelia trilobata and Bidens pilosa) in South China with hydroponic media containing different forms of N (i.e. NO3?, NH4NO3 and NH4+) at equimolar concentrations. Our results showed that the N forms significantly affected the growth, biomass allocation and physiological traits of the plants. All four invasive plants supplied with NO3? alone had better performance and greater allocation to root biomass than did plants that were supplied with NH4+ alone. Moreover, the photosynthetic rate, pigment content and photosystem II activity of plants supplied with NO3? or NH4NO3 were significantly higher than those of plants supplied with NH4+alone. The results suggested that all four invasive plants preferred NO3? rather than NH4+, and changes in NO3? played an important role in furthering the invasions of these plants than did changes in NH4+. Our results implied that decreasing NO3? may be a useful tool for controlling and managing invasive plants preferring NO3?. In addition, this study highlighted the importance of considering plant N form preference to better understand plant invasions.  相似文献   

20.
The objective of this study was to investigate the potential of native Thai species for reclaiming salt-affected areas in Thailand. Plant species diversity in Nakhon Ratchasima Province in northeast Thailand, and their soil characteristics (texture, electrical conductivity (ECe), exchangeable sodium percentage (ESP), and pH) were measured. A total of 19 species in 16 genera of 12 families were found, among which the most abundant species belonged to the Poaceae and Cyperaceae families. The highest values of ECe were found near the surface (0–20?cm) with an average range between 30–80?dS?m?1, while lower values in the range of 15–25?dS?m?1 were found at lower depths (20–100?cm). Soil conditions in the subplots with plant coverage showed lower ECe and ESP when compared to plots without vegetation. Seeds from the three most frequently occurring species, including Azima sarmentosa, Gymnosporia mekongensis, and Buchanania siamensis, were then tested for germination at different salinities. Seeds of all three species germinated at high salinities, from 25–45?dS?m?1, with total germination ranging 40–90%. Together with the ability to germinate at high salinities, these native species showed deep, rapid root elongation, likely to escape high surface ECe levels (approximately the top 30?cm). Planting these species in areas with vegetation coverage would aid successful reclamation of saline areas. Reclaiming salt-affected soils will not only improve local farmer’s economic status, but can also reduce the extent of deforestation, benefiting the entire ecosystem.  相似文献   

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