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1.
As part of an investigation into the agricultural potential of under-exploited Mediterranean Viceae, anti-nutritional factor concentrations were measured in the seed of 7 species. These included: V. sativa(subsp. amphicarpa(L.) Batt., subsp. macrocarpa(Moris) Arcang, subsp. nigra(L.) Ehrh., subsp. sativa), V. ervilia L., V. faba L. (var. faba, var. minor Peterm.), V. narbonensis L. (var. aegyptiaca Kornhuber ex Asch. et Schweinf., var. affinis Kornhuber ex Asch. et Schweinf., var. jordanica H. Schaef., var. narbonensis, var. salmonea(Mout.) H. Schaef.), and relatives, including V. johannis Tamamsch., (var. johannis, var. procumbens H. Schaef.), V. hyaeniscyamus Mout., and V. serratifolia Jacq. Both quantitative and qualitative differences in seed chemistry were observed. Condensed tannins, phenolics and proteinase inhibitors were found in varying concentrations in all taxa. The highest concentrations of phenolic secondary metabolites (0.8–1.4% leucocyanidin equivalents, 9.5–16.4 mg/g phenolics) were found in V. faba, the V. narbonensis relatives and V. sativa subsp. macrocarpa. These taxa also tended to contain low levels of proteinase inhibitors (0.25-0.55 mg trypsin/mg protein), whereas the opposite was the case for V. ervilia(2.1 mg t/mg p). V. narbonensis was intermediate both in terms of tannin and proteinase inhibitor levels. In contrast, the non-protein amino acids tended to be more specific in their distribution. Concentrations of canavanine varied from 0.04-0.11% in the seed of V. ervilia, and may constrain the end-use of the grain, given that pigs are sensitive to concentrations as low as 0.08% in their diet. In V. sativa variation of -glutamyl--cyanoalanine within and between subspecies (0.41–1.36%) is not sufficient to make the grain palatable to monogastrics, since > 0.075% inclusion in the diet causes mortality in chicks. In V. narbonensis, there was no significant variation between most varieties for -glutamyl-S-ethenyl cysteine (GEC), a non-protein amino acid peptide which reduces grain palatability. However, lower concentrations were found in V. n. var. jordanica and its near relatives, V. johannis, V. hyaeniscyamus and V. serratifolia(1.3-1.6%, compared with 1.9+/–0.02% in all remaining V. narbonesis sub-species). Anti-nutritional factor concentrations were used to visualize taxonomic relationships using hierarchical cluster analysis. The V. narbonensis varieties were closely aligned with their near relatives, V. johannis, V. hyaeniscyamus and V. serratifolia. In contrast V. faba was positioned closer to the V. sativa subspecies than either to V. narbonesis or its near relatives. V. ervilia was the most distantly related species. Across all taxa proteinase inhibitors and condensed tannins or total phenols were negatively correlated (r=– 0.72, P < 0.009). This may be a mechanism which minimizes wasteful resource allocation to chemical defense, because the 2 anti-nutritional factors are functionally substitutable, since they both reduce the availability of protein in plant material. Thus taxa investing in high concentrations of proteinase inhibitors do not duplicate chemical defense mechanisms by simultaneously producing large amounts of tannins and phenolics.  相似文献   

2.
Low molecular weight carbohydrates of seeds of 10 species of Vicia, namely: V. angustifolia, V. articulata, V. cordata, V. ervilia, V. johannis, V. macrocarpa, V. monantha, V. narbonensis, V. pannonica and V. sativa were analyzed by the high resolution gas chromatography method. Seeds of the investigated species contain common (glucose, fructose, myo-inositol, sucrose, galactinol, di-galactosyl myo-inositol and raffinose family oligosaccharides—RFOs) and species-specific carbohydrates (d-pinitol and its α-d-galactosides—in V. articulata, V. monantha and V. pannonica or d-ononitol and its galactoside—in V. ervilia). Among the species containing in seeds RFOs as the main α-d-galactosides (V. angustifolia, V. cordata, V. johanensis, V. macrocarpa, V. narbonensis and V. sativa), an additional subgroup can be separated, which contains a set of unknown compounds (found in V. angustifolia, V. cordata and V. macrocarpa). Moreover, several other unidentified carbohydrate-containing compounds were detected exclusively in seeds of V. ervilia. The concentrations of total soluble carbohydrates (TSCs), including sugars, RFOs, cyclitols and galactosyl cyclitols and unknown compounds, in seeds differ significantly (P < 0.05) among the species. RFOs and sucrose are the main fractions in TSCs, with the exception of V. pannonica seeds, containing more galactosyl pinitols, and V. ervilia, in which unknown compounds account for 50% of TSCs. In V. ervilia RFOs occur at the lowest concentration (9.32 mg g?1 seeds), and the concentration of DGMI (di-galactosyl myo-inositol) is comparable with that of RFOs, which is unusual among all the investigated Vicia species.  相似文献   

3.
Seventy three accessions of the sevenVicia species belonging to Sativa speciescomplex were screened for nuclear and organellar restriction fragmentlength polymorphic (RFLP), and random amplified polymorphicDNA (RAPD) markers. Total genomic DNAs of 73 accessions wasrestricted with three enzymes, and the restriction fragments werehybridized to the wheat rDNA probe pTa71 (containing 18S, 5.8Sand 25S rDNA genes, and spacers), and faba bean probes Ver6-5 (entire intergenic spacer flanked by small part of25S and 18S fragments) and Ver 18-6 (part of thecoding region of the gene and internal transcribed spacers). InXbaI digests, 16 repeat unit length classes in24 combinations were identified. Digestion withEcoRI and DraI gave2–4 and 1–3 fragments, respectively, with detectablehybridization to the probes, indicating the existence of internalXbaI sites. All the accessions produced 3.5 EcoRI fragment arising fromcoding region of the repeat unit. Four hundred and eighteen RAPDmarkers among 45 accessions were identified with 14 arbitrary10-base primers. The percentage of polymorphic bands withinspecies ranged from 20 in V.angustifolia to 98% inV. nigra. Both RFLP andRAPD markers were unable to assess the relationships betweenaccessions within species as there was often much closer resemblancesbetween certain accessions of different species rather than betweenaccessions within each taxon. This analysis supports the view basedon morphological, cytogenetical and crossability data that it is notpossible to classify Sativa species complex into a small finitenumber of taxa which are clearly circumscribed, and that the complexrepresents a unique case of rapid evolution and incipient speciation.A study of chloroplast and mitochondrial RFLPs was undertaken toanalyze phylogeny through maternal lineage. Chloroplast DNArestriction fragment patterns, using 13 restriction endonucleases,revealed 92.6 to 99% homology between the seven species.Twelve enzyme-probe combinations yielded identical fragmentpatterns for all the seven species. The molecular sizes of thechloroplast DNAs obtained were similar (121.5–123.5), indicating that they had all lost one of theinverted repeats. Total DNAs digested with three restriction enzymesand hybridized to six heterologous probes of mitochondrial originyielded monomorphic bands in five enzyme—probe combinationsacross all the 73 accessions. In other combinations as well,40–66 accessions yielded monomorphic profiles. The smallvariation in the remaining accessions was not species-specificsince the same profiles were present in more than one species. Theseresults i) strongly suggest that the seven species within thecomplex share a common ancestor, or direct lineage and, ii)indicate that these species should be relegated to a rank, perhaps ofsubspecies, within V.sativa species complex.  相似文献   

4.
Field evaluation of an Amaranthus genetic resource collection in China   总被引：1，自引：0，他引：1  
A total of 229 genotypes of 20 Amaranthus species from the United States Department of Agriculture – Agricultural Research Service (USDA – ARS) National Plant Germplasm Amaranth Collection was evaluated in field experiments in Beijing and Wuhan, China, in 1994. Agronomic traits, including plant height, maturity, leaf number and color, stem color, seed color, branch number, 1000-grain-weight, yield per plant, and resistance to stresses (including diseases) were measured. The results indicated: 1. Many of the species were sensitive to daylength; 2. Cultivated genotypes generally had higher grain yield but were more seriously affected by diseases than non-cultivated species; 3. There was wide diversity in agronomic traits among Amaranthus species and among genotypes within the same species, and several genotypes were identified that appeared to carry favorable agronomic traits of immediate use in cultivar improvement; 4. For introduction of genotypes for use in plant breeding in China, selection should be partially based on matching the climates of the location of origin and the target area for production.  相似文献   

5.
A plant growth-promoting rhizobacterium (Azospirillum brasilense Sp7) and a bio-control fungus, which can solubilize insoluble phosphorus (Trichoderma harzianum Rifai 1295-22), were evaluated for their single and combined effects on dry bean (Phaseolus vulgaris) and wheat (Triticum aestivum L.) grown in soil. A pot experiment with bean and a field experiment with both bean and wheat were established. In contrast to single inoculation of Trichoderma, the single inoculation of Azospirillum and the double inoculation did not significantly (P >0.05) increase nodule numbers and nodule mass at 45 days after planting in pot grown beans. However, the Azospirillum inoculation with supplementary phosphorus significantly (P <0.05) increased nodule mass. There were no significant (P >0.05) differences among the inoculation treatments for plant dry weight, total plant nitrogen, and total plant phosphorus at 45 days after planting in both pot and field experiments with bean. However, the combined inoculation and rock phosphate application at 1 Mg ha–1 significantly (P <0.05) increased bean seed yield, total seed nitrogen and phosphorus in the bean field trial. This treatment more than doubled the mentioned properties compared to the control. The microbial inoculations, with the exception of the combined inoculation, significantly (P <0.05) increased total seed nitrogen, but never affected seed yield in the wheat field trial (P >0.05). The combined inoculation improves many plant and yield parameters and, therefore, has some advantages over single inoculation provided that rock phosphate was supplied at an amount not exceeding 1 Mg ha–1. Higher rock phosphate application rates decreased many plant and yield parameters in our study.This work was carried out at Gaziosmanpaa University, Tokat, Turkey.  相似文献   

6.
Strongly reducing organic substances (SROS) and iron oxides exist widely in soils and sediments and have been implicated in many soil and sediment processes. In the present work, the sorptive interaction between goethite and SROS derived from anaerobic decomposition of green manures was investigated by differential pulse voltammetry (DPV). Both green manures, Astragalus sinicus (Astragalus) and Vicia varia (Vicia) were chosen to be anaerobically decomposed by the mixed microorganisms isolated from paddy soils for 30 d to prepare different SROS. Goethite used in experiments was synthesized in laboratory. The anaerobic incubation solutions from green manures at different incubation time were arranged to react with goethite, in which SROS concentration and Fe(II) species were analyzed. The anaerobic decomposition of Astragalus generally produced SROS more in amount but weaker in reducibility than that of Vicia in the same incubation time. The available SROS from Astragalus that could interact with goethite was 0.69 ± 0.04, 0.84 ± 0.04 and 1.09 ± 0.03 cmol kg−1 as incubated for 10, 15 and 30 d, respectively, for Vicia, it was 0.12 ± 0.03, 0.46 ± 0.02 and 0.70 ± 0.02 cmol kg−1. One of the fates of SROS as they interacted with goethite was oxidation. The amounts of oxidizable SROS from Astragalus decreased over increasing incubation time from 0.51 ± 0.05 cmol kg−1 at day 10 to 0.39 ± 0.04 cmol kg−1 at day 30, but for Vicia, it increased with the highest reaching to 0.58 ± 0.04 cmol kg−1 at day 30. Another fate of these substances was sorption by goethite. The SROS from Astragalus were sorbed more readily than those from Vicia, and closely depended upon the incubation time, whereas for those from Vicia, the corresponding values were remarkably less and apparently unchangeable with incubation time. The extent of goethite dissolution induced by the anaerobic solution from Vicia was greater than that from Astragalus, showing its higher reactivity.  相似文献   

7.
The genetic diversity of 58 wild and weedy populations representing taxa within the V. sativa aggregate from the former USSR, 4 cultivars of V. sativa, 2 accessions of V. cordata and 3 accessions of V. macrocarpa from Mediterranean countries were analysed using randomly amplified DNA fragments (RAPDs) and seed protein electrophoresis (SDS-PAGE). Interspecific variation between taxa in the V. sativa aggregate could readily be detected using both techniques. RAPDs and seed protein patterns were found to be an effective means of identifying accessions that cannot be identified clearly by morphological criteria alone. RAPD and seed protein analysis revealed a clear relationship between observed genetic variation of populations and their geographical distribution. Populations from each region had their own gene pools. Geographical variation was detected in V. segetalis. The degree of genetic divergence between local populations was usually related to proximity. In several locations where wild and weedy populations of different V. sativa agg. taxa grow sympatrically, intermediate forms could be detected at the DNA and protein levels. Both RAPD and seed protein analysis support the view that the V. sativa aggregate consists of 8 taxa warranting recognition at the species level. Several species in this aggregate are evolving intra-specific groups which can readily be detected at the molecular level.  相似文献   

8.
Since autumn-sown faba beans possess several advantages including higher seed yield over the spring cultivars, the study was aimed to screen and select cold tolerant accessions of faba beans (Vicia faba L.) and compare these to wild species in the highland of the west Mediterranean region, Turkey. A total of 114 accessions of Vicia species including 109 accessions of faba bean, three accessions of narbon bean (V. narbonensis L.) and two accessions of V. montbretii Fisch. et C.A. Mey. were screened for cold tolerance at seedling stage in two successive years, 2005–2006 and 2006–2007 growth seasons. Accessions were evaluated for cold tolerance using a 1 (Highly cold tolerant)-5 (Highly cold susceptible) visual scale. Considerable variation was found for cold tolerance and some agronomical characteristics in faba beans. Wild relatives of faba bean were found to be more tolerant to cold than those of cultivated faba beans. Although some pigmented accessions were free from freezing damage at −9.6°C without snow cover, accessions with white flowers were damaged. The proposed screening technique could easily be used to evaluate many faba bean accessions for cold tolerance. To increase yield, it was concluded that the cold tolerant accessions with high yield could be grown as autumn-sown crop in the target environment.  相似文献   

9.
The earthworm population in a winter cereal field in Ireland was studied over a 3-year-period and its effects on soil and N turnover were assessed. The mean annual population density was 346–471 individuals m-2 and the mean biomass was 56.9–61.2 g m-2. Twelve species were recorded, the most abundant being Allolobophora chlorotica followed by Aporrectodea caliginosa, and 242 mg at 5°C to 713 mg at 10°C in the case of juvenile Lumbricus terrestris. Gut contents (dry mass of soil) comprised 6.7–15.5% of the A. caliginosa live mass, and 9.7–14.7% of the Lumbricus terrestris mass. Annual soil egestion by the field population was estimated as 18–22 kg m-2. Tissue production ranged from 81.7 to 218.5 g m-2, while N turnover resulting from mortality was calculated as 1.5–3.9 g m-2 depending on the year and the method of calculation. Earthworms were estimated to contribute an additional 3.4–4.1 g mineral N to the soil through excretion, mucus production, and soil ingestion. Independent estimates of N output via mucus and excretion derived from 15N laboratory studies with Lumbricus terrestris were 2.9–3.6 g m-2 year-1.  相似文献   

10.
Iran is one of the primary centers of diversity for wheat and its relatives. Wild wheats, in particular diploid species, are extensively distributed in various parts of Iran. Of these, the existence of two “A" genome donor species, i.e., T. baeoticum and T. monococcum, has already been reported in Iranian floras. However, the existence of the other important “A" genome donor, i.e., T. urartu, has not been clearly reported. In a germplasm collection survey in several regions of Iran, T. urartu was identified, collected, and described, and is reported here for the first time. In a detailed and extensive taxonomic program, the collected germplasms of the above three species were studied. Morphological characters and species-specific traits of the three species were evaluated and compared. Using the monographs by Gandilyan (1980) and Dorofeev et al. (1979) for the collected germplasms, 14 varieties were identified of T. boeoticum, 3 varieties of T. urartu, 2 forms of T. monococcum. Of these 5 varieties of T. baeoticum ssp. baeoticum (var. albinigrum, var. garniense, var. zuccarinii, var. baeoticum, var. pseudobaeoticum), 3 varieties of T. baeoticum ssp. thaoudar (var. abovjanii, var. albinigrescens, var. ebrahimzadehae, var. viridinigrireuteri) and 1 variety of T. monococcum (var. mansfeldii) are new to Iran. In addition, 1 variety of T. baeoticum ssp. baeoticum (var. khorramabadicum), 3 varieties of T. baeoticum ssp. thaoudar (var. ebrehimeadena var. taleghanicum, var. ilamicum) and 2 varieties of T. urartu (var. iranicum, var. sardashticum) are new to the wheat botany.  相似文献   

11.
Using Tn5 mutagenesis of lysogenic Sinorhizobium meliloti strain L5–30 (L54), three neomycin-resistant transconjugants differing in phage-resistance profiles were isolated. Two of them increased the dry weight of plants and were capable of establishing root nodules, whereas the third one was ineffective. The bacterium-phage interaction did not have observable consequences in the Medicago sativa - S. meliloti symbiosis because it did not affect the number of nodules on M. sativa or plant dry weight.  相似文献   

12.
Increasing and maintaining crop residues in predominantly cereal-based rotations of the US Pacific Northwest is critical to controlling soil erosion. The core collection of lentil (Lens culinaris Medik.) germplasm comprising 287 accessions was evaluated for variation in phenological, morphological and growth parameters including seed yields and residue amounts over a two-year period under conventional tillage and no-till conditions. The objectives of this study were (i) assess lentil genetic variation in germplasm for variation in biomass production and seed yield, (ii) assess the relationship of phenological and morphological traits with biomass and seed yield and (iii) identify high biomass producing germplasm for use as parents in the breeding program. Days to flowering and days to maturity ranged from 31 to 78 and from 71 to 106 days, respectively. Time to flowering in terms of cumulative heat units was a more efficient measurement than days to flowering. Plant height and plant canopy width had a significant association with total biomass, seed yield and residue amounts. Total biomass ranged from 788–6389 kg ha–1 under conventional tillage, while the range under no-till conditions was 1045–6195 kg ha–1. Most of the lines with higher biomass also produced the highest seed yields and residue amounts. Overall, only one accession produced more residue than `Laird'. In the more favorable environment of 1997, six accessions exceeded the control cultivars, `Laird' and `Indianhead', for residue amounts, and seven and twenty-four accessions exceeded control cultivars, `Pardina' and `Brewer', for seed yield. Results indicated that plant height, canopy width at maturity and seed yield explained most of the variation in biomass and residue production. Large seeded germplasm consistently had a longer reproductive growth period than small seeded accessions and had 17%, 7% and 21% more biomass, seed yield and residue, respectively. Our data indicated significant variation in lentil germplasm for biomass, seed yield and residue amounts to warrant their use in the breeding program.  相似文献   

13.
DNA variation was studied at the intra- andinterspecific levels within the genus Passiflora, with particular emphasis on the subgenusTacsonia and its relationship with the subgenusPassiflora. AFLP fingerprints were generated for35 accessions from 21 species, 14 of which belong to subgenusTacsonia, and four to subgenusPassiflora. The morphologically intermediateP. manicata (subgenusManicata) was also included, as wereP. trinervia (subgenusPsylanthus) and P.alnifolia (subgenus Decaloba). The two latter were used as outgroup species. Twoprimer combinations generated 34–80 scorable fragments pergenotype for a total of 260 fragments. Polymorphism analyses spannedthe levels from individual genotype to section. SubgenusTacsonia presented wide genetic variability atboth intra- and interspecific levels, particularly within wildspecies. The classification based on these markers generally agreeswell with current taxonomic definitions of common species, but lesswith definitions of sections. A geographical component was evident inthe intraspecific variation of P.mixta, P.tripartita var. mollissimaand P. tarminiana, withwider variation in Ecuador and Peru than in Colombia and Venezuela.These same three species, plus P.cumbalensis, formed adjacent clusters, showingcloser affinity with each other than with the other species ofsubgenus Tacsonia. As expected, P. manicata clustered at anintermediate position between subgenera Tacsoniaand Passiflora.  相似文献   

14.
China, the native home of ramie (Boehmeria nivea (L.) Gaud. var. nivea), possesses many wild species in the genus Boehmeria Jacq., including many those rare valuables in some characteristics such as stress resistance and fiber qualities that can be used for biological engineering, genetics and breeding research. From 1995 to 1999, 130 samples of the genus Boehmeria that belong to 22 species and 6 varieties, were collected in 34 counties of 14 provinces in China in the region of N18.8–34.2° and E101–121°. The gene pool of wild species of the genus Boehmeria was constructed at Yichun, Jiangxi Province and 77 samples belonging to 8 species and 4 varieties were conserved alive. The collected species are classified into 5 sections i.e. Boehmeria, Tilocnide Bl., Zollingerianae Satake, Phyllostachys W. T. Wang and Duretia Bl., according to the morphology. They may also be divided into hygric type, moderately hygric type, semi-shade-hygrophyte and xeromorphy, based on their ecological adaptability and primitive growing circumstances. The distribution of the wild species and populations in the genus Boehmeria is related to the altitude.  相似文献   

15.
The fungicide Vitavax RS and the seed polymer Extender were sequentially applied to canola seed to determine their effect on the fungal inoculum, Penicillium bilaiae. In the laboratory, the fungicide was applied at the recommended rate of 23.4 ml kg–1, and the polymer was applied by the manufacturer. Significant death of P. bilaiae occurred after 2.5 days on the Vitavax RS-treated seed and after 1.5 days with the seed treated with both Vitavax RS and Extender. In field treatments, the seed was sown at six sites in the fall just prior to freeze-up. Results from the laboratory experiment indicate that there should be no harmful effects of the Vitavax RS and Extender on the P. bilaiae at the time of seeding because the seeds were sown within 2 h of inoculation. The environmental extremes in 2001 and 2002 resulted in large variations in the data. P. bilaiae did not increase yield under these conditions.  相似文献   

16.
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17.
Summary Two annual species of Sesbania, S. aculeata and Sesbania sp. PL Se-17, were field evaluated as green manure for wetland rice in an alkaline soil. The two species were raised as a catch crop during summer in a wheat-rice rotation, and added as 24.7 and 20.8 t ha–1 of green matter, 116 and 98 kg N ha–1, respectively, after 45 days of growth. For the optimum green manuring effect on rice grain yield and N uptake, S. aculeata required 5 days of decomposition (after turning in and before rice transplantation), whereas no decomposition period was necessary for Sesbania sp. PL Se-17. The effect on grain yield and N uptake of rice was equivalent to an application of 122 and 78 kg ha–1 of chemical N, for the two species, respectively. There was no residual effect of the green manuring on the soil N status after rice harvest.  相似文献   

18.
Weedy rice is a complex of Oryza morphotypes widely distributed in commercial rice fields, which interfere with rice cultivation, seed production, industrial processing and commercialization of this crop in several countries. The objective of this study was to characterize the weedy rice complex of Costa Rica by comparing it with the cultivated and wild rice species found in the country. A collection of weedy rice accessions, representative of the morphotypes found in the country, was established and characterized. Their morphometric relationships were established by comparing 27 morphological traits with commercial rice cultivars, landraces and wild Oryza species and by performing a multivariate analysis. Twenty-one weedy rice morphotypes were identified among 735 weedy accessions by using a three-digit code based on seed characters. Three principal components (PCs) explained 66.25% of the variation observed. The first PC accounted for 36.21% of the variation and separated CCDD genome type Oryza latifolia and O. grandiglumis from AA genome species O. sativa, O. glumaepatula, O. rufipogon and O. glaberrima. The second (18.9%) and third (11.14%) PCs separated the weedy morphotype groups from the AA genome species O.sativa, O. glaberrima and O. rufipogon. The weedy morphotypes were scattered between the indica commercial rice varieties, the cluster landraces–glaberrima and O. rufipogon. Additionally, a group of morphotypes showed intermediate characteristics between O. sativa and O. rufipogon, suggesting that hybridization could have taken place in the past between these species. None of the morphotypes collected in Costa Rica clustered with the allotetraploids CCDD species or O. glumaepatula.  相似文献   

19.
We studied the dynamics of microbial C, N, and P in soil cropped with rice (Oryza sativa) and lentils (Lens culinaris) in a dryland farming system. The crop biomass and grain yield were also studied. The microbial biomass and its N and P contents were larger under the lentil than under the rice crop. Microbial nutrients decreased as the crops grew and then increased again. Farmyard manure and NPK fertilizer applications increased the level of microbial nutrients, crop biomass, and grain yield by 35–80%, 55–85%, and 74–86%, respectively. However, these applications had no significant effect on most of the soil physicochemical properties in the short term. The microbial biomass was correlated with the crop biomass and grain yield. The calculated flux of N and P through the microbial biomass ranged from 30–45 and 10–19 kg ha-1 year-1, respectively. Cultivation of a cereal crop followed by a leguminous crop sustains higher levels of microbial nutrients and hence greater fertility in impoverished tropical arable soils. The soil microbial biomass appears to contribute significantly to crop productivity by releasing nutrients, and applications of manure, either alone or with fertilizers, promote this effect more strongly than the application of NPK fertilizers alone.  相似文献   

20.
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