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1.
以提高胶冻样芽孢杆菌在土壤中的存活率、减缓其衰亡速率,延长存活时间,提高其对土壤难溶性钾的解钾效率为目的,利用不同种类的秸秆生物质炭与胶冻样芽孢杆菌进行复配筛选。通过室内培养试验发现,中性小麦秸秆炭可作为胶冻样芽孢杆菌较理想的载体。当土壤培养35天后,土壤速效钾含量在施用炭基解钾菌肥条件下较空白提高了28.53%,较小麦秸秆炭和纯菌液处理分别提高了20.75%、13.41%。纯菌液处理土壤中胶冻样芽孢杆菌的菌落数从1.1×10~9个/g土降为9.0×10~5个/g土,而炭基解钾菌肥处理则为1.4×10~7个/g土。田间施用炭基解钾菌肥能够提高番茄植株和果实中的全钾含量;提高番茄产量和品质,显著提高番茄Vc含量,降低硝酸盐含量。因此,中性小麦秸秆炭与胶冻样芽孢杆菌的复配能够提高菌剂的存活率,有效促进土壤中矿物态钾的释放。  相似文献   

2.
Extensive germplasm resources are present in collections of Lotus corniculatus and L. uliginosus, two forage species that are valuable in situations where other legumes are not persistent. Naturalised populations in many regions are the primary gene pool for genetic improvement of these species and interspecific hybrids are an important source of variation for agronomic and forage quality traits. Although previous research has provided evidence that selection for optimal levels of condensed tannins and herbage productivity are feasible breeding objectives, less is known about correlations of condensed tannin with other parameters of nutritive value. A germplasm collection of 38 accessions in both species from 9 geographic regions was used as a data base to determine these correlations. Forage of each accession was sampled in two successive years from a field site in south-eastern Australia and analysed for condensed tannin, in vitro digestible dry matter, nitrogen, acid detergent fibre and neutral detergent fibre. In both species condensed tannin was negatively correlated with in vitro digestible dry matter and nitrogen. This result helped to identify potentially valuable accessions with low condensed tannin (<4% of dry weight) and high in vitro digestible dry matter (>70%). One of these was an interspecific hybrid of L. uliginosus and L. corniculatus, confirming the view that interspecific hybridization would be a valuable avenue for improvement of agronomic and forage quality characters in Lotus species.  相似文献   

3.
Twenty nine germplasm lines of Chenopodium quinoa and two of Chenopodium berlandieri subsp. nuttalliae were evaluated for 12 morphological and 7 quality traits for two test seasons. The 19 traits were analyzed for cluster and principal component analysis. The first four PCs contributed 78.70 % of the variability among the germplasm lines. The first PC accounted for 39.5% of the variation and had inflorescence/plant, plant height and stem diameter as the traits with largest coefficients, all with positive sign. The characters with greatest positive weight on PC2 were days to maturity (0.309), inflorescence length (0.260) and branches/plant. All the germplasm lines were grouped into six clusters based on average linkage method. Cluster III had high values for seed yield and most of the quality traits but showed a small seed size. The dendrogram separated the two lines of C. berlandieri subsp. nuttalliae from the quinoa lines.  相似文献   

4.
赵政  陈巍  王欢  夏可心  高仁维  姜斯琪  庞冠  蔡枫 《土壤学报》2018,55(5):1243-1253
研究利用植物促生菌提高肥料效率以部分替代化肥。采用大田试验结合连续盆栽试验的方法,以100%化肥(CF)为对照,设置如下处理:75%化肥配施普通有机肥(OF)或木霉微生物肥(BF)或木霉孢子悬液(SS)。结果表明,75%化肥配施以一定量(每株50 g)木霉微生物肥可维持田间番茄稳产,与100%化肥处理产量相当;而与普通有机肥或木霉孢子悬液灌根配施则会显著降低番茄产量,连续栽种4季后,产量下降35%以上。此外,BF处理可显著提高番茄果实的品质,与CF相比,总可溶性糖和维生素C含量分别提高35%~54%和2%~23%,而硝酸盐积累量下降32%~46%。究其原因,BF处理中木霉功能菌的有效定殖促进了番茄根际细菌、真菌、放线菌的增殖,土壤养分的有效性显著提高,表现为根际微生物数量与多项土壤肥力指标呈显著相关关系。综上,木霉微生物肥与减量化肥配施,可有效保证番茄稳产,提高番茄品质,长期施用还可提高土壤微生物数量、改善土壤肥力。  相似文献   

5.
6.
The extent and patterns of distribution of genetic variation among 80 sorghum (Sorghum bicolor (L.) Moench) germplasm accessions from Ethiopia and Eritrea were investigated using RAPD with 20 oligonucleotide primers. The primers generated a total of 147 polymorphic bands across the 80 accessions with a mean of 7.35 bands per primer. Estimation of the extent of variation by the Shannon-Weaver diversity index revealed an intermediate level of overall variation (H = 53), although the levels varied among regions of origin of the accessions. Partitioning of the total variation revealed considerable variation (77%) within the region of origin of the accessions and the remainder (23%) among regions of origin. Similarly, a large portion (94%) of the total variation was found within the adaptation zones compared to among the adaptation zones (6%). The results suggest a weak differentiation of the sorghum material both on regional and agro-ecological bases, which could be ascribed to the high rate of outcrossing in cultivated sorghum and its free natural hybridization with its wild and weedy relatives, as well as to seed movement by humans. The average genetic dissimilarity was found to be 36% among the 80 accessions and 13% among the 15 regions of origin. Cluster analysis failed to group accessions of the same region or the same adaptation zone, which further confirmed the weak differentiation of the material studied. The clustering pattern of the regions of origin was broadly concordant with previous clustering patterns obtained using morphological characters, in which regions with broad agro-climatic conditions were grouped together.  相似文献   

7.
A total of 3600 entries of tef [Eragrostis tef (Zucc.) Trotter] germplasm collections representing 36 populations from six regions of Ethiopia were evaluated for phenotypic diversity in six qualitative and phenologic characters. High values of Shannon–Weaver diversity index ( ) were recorded for most characters in each population. Monomorphism was high for anther color (purple) and panicle form (loose). Larger variances for were obtained among regions than among populations within a region from hierarchical analysis of variance. Significant (P<0.05) to highly significant (P<0.01) t-values were observed among values of some regions for seed color, panicle form and days to maturity. A substantial level of variance (P<0.05) was obtained for populations within altitudinal zones only for days to maturity. Altitudinal zones exhibited similar levels of diversity across characters for these collections. Generally, considerable variations important for tef improvement work have been observed and regions with highest diversity for some traits have been suggested for future in situ or ex situ germplasm conservation works. Although similar mean diversity indices were obtained among regions, they were non overlapping.  相似文献   

8.
Wild populations of Vitis vinifera L.␣have been located in Portugal. Morphological characterization was carried out in three populations located in Alcácer do Sal, Castelo Branco, and Montemor-o-Novo, and then compared using multivariate discriminant analysis. These populations were from three different hydrological basins, therefore cross-pollination was not possible. It was verified that in each population all plants were different. The data suggest that the frequency of female and male plants is rather variable in wild populations. The morphology of the adult leaf, from the Alcácer do Sal population, had particular features when compared with Castelo Branco and Montemor-o-Novo populations, which were more homogeneous. The length of teeth compared with width at the end of the base, and the density of prostrate hairs between and on main veins (lower side) were the variables which allowed the best discrimination among populations.  相似文献   

9.
Ten traditional, Turkish okra cultivars (Bat? Trakya, Akköy 41, Kabakl? II, Denizli, Denizli uzun, Bornova (TR-57377 and TR-57420), Amasya Çiçek, Bal?kesir T-1, A?lasun/Burdur) and one commercial cultivar (Sultani/May Seed Company) were selected to represent the variability within domestic okra germplasm from the Anatolian Plateau. Replicated field trials were conducted to evaluate a total of 21 morphological, horticultural and physiological characteristics. Principal component (PC) analysis revealed that first two PC axes explained 49.66% of the total multivariate variation with the first six PC axes explaining 84.23%. The first PC axis separated number of locules, mature pod length and internode length, while the second PC axis separated pod yield/plant, pod number/plant, pedicel length and number of branches. All 21 characters were statistically significant among the cultivars and had at least one high coefficient in at least one of the first six PC axes, which demonstrated that all of them served as distinguishing characters among the cultivars. By using the unweighted pair-group method with arithmetic average four main clusters were consistently formed across all years. The four clusters were also related to the eco-geographic distribution of the cultivars. Each cluster members were also described for their main characteristics, which also provide useful criteria for further evaluation of okra germplasm across Turkey.  相似文献   

10.
One hundred and thirty SSR markers from wheat, maize and sorghum were screened for the transferability to Paspalum. The transfer rate was 67.5, 49.0 and 66.8% respectively. This would be a very efficient approach for DNA marker development for species which are not well studied molecularly. The polymorphism level for transferred SSR markers was 51.5% within species (Paspalum vaginatum) and 87.1% among Paspalum species. The high level of polymorphism is directly related to the high degree of heterozygosity maintained by its way of reproduction, i.e. self-incompatibility. Forty transferred polymorphic SSR markers were selected and used for characterization and evaluation of seventy-three Paspalum accessions. In total, 209 polymorphic bands were detected from these 40 SSR markers, with an average of five polymorphic bands per marker. The Paspalum accessions clustered into three major groups. Two very similar dendrograms can be generated from either 109 or 209 polymorphic bands. This led us to determine that 18 of the transferred SSR markers were sufficient for genetically differentiating the investigated germplasm accessions. The number of SSR markers required for germplasm characterization and evaluation is discussed. This is the first report of the transfer of SSR markers from major field crops to newly emerged environmental turfgrasses.  相似文献   

11.
Patterns of geographical diversity, and the relationship between agro-morphological traits and fatty acid composition were assessed for 193 safflower (Carthamus tinctorius) accessions representing forty countries. Accessions were assigned to eight groups based on geographical proximity. Cluster and Principal Component analyses were performed to assess patterns of diversity among the accessions and to select the most distant accessions from each of eight groups for analysis of randomly amplified polymorphic DNA (RAPD) markers. There was a large amount of diversity for agro-morphological traits, fatty acid composition, and RAPD markers. Most correlations among different traits were rather low. Plant height showed a positive correlation with days to flowering (r = 0.63**). Palmitic acid was positively correlated with stearic acid and oleic acid values, and negatively correlated with linoleic acid (< 0.01). Oleic acid and linoleic acid showed a strong negative correlation (r = −0.89**). The first three principal components together explained 59% of the variation, however, neither principal component analysis (PCA) nor marker analysis revealed a clear relationship between diversity pattern and geographical origin. Accessions from some geographical regions tended to group together, such as accessions from South Western Asia, Central Western Europe, and the Mediterranean region. The correlation between the morphological matrix and the genetic matrix based on RAPD markers was not significant (r = 0.027). Wide diversity in safflower germplasm indicates a considerable potential for improving this crop for both agronomic and quality traits.  相似文献   

12.
The aim of this study is to characterize 10 European chestnut (Castanea sativa Mill.) accessions which were selected among 80 accessions at the end of a selection study in Nazilli in Turkey. During the harvest periods in 2001, 2002 and 2003, European chestnut accessions were examined. Nineteen morphological, pomological and biochemical characters were used. Significant genotype×year interaction were found for all traits but one. Multivariate methods, including cluster and principal component analysis were performed to characterize the accessions. The first five principal components account for 86.44% of the total variance of all traits, indicating a high degree of correlation among the characteristics analyzed. High level of phenotypic proximity was found between the accessions N-20-2 and N-5-1 based on pomological, morphological and biochemical characteristics.  相似文献   

13.
Inter simple sequence repeat (ISSR) markers were used to evaluate levels of genetic similarity among Coffea arabica L. accessions from Tanzania and to estimate levels of genetic similarities in C. arabica and diploid coffee species. The six ISSR primers used generated a total of 82 fragments and the dissimilarity values ranged from 0.21 to 1. Mean dissimilarity values between provenances (0.56–0.85) were higher than within provenances (0.37–0.68). Cluster analysis based on Nei’s genetic distances showed C. arabica provenances grouping based on geographical origin. Two major clusters were formed that constituted of provenances from Kilimanjaro and Arusha in one sub-cluster; Tanga and Morogoro in the other; the second cluster had Mbeya provenances and diploid species, respectively. The implication is that Mbeya provenances are different from the rest of Tanzanian C. arabica. A principal coordinate analysis (PCA), whose first three coordinates explained 43% of the variation, showed similar groupings as in the cluster analysis. A separate cluster analysis of diploid species showed a distinct separation of the three species used. ISSR data gave results similar to previous findings from random amplified polymorphic DNA(RAPD) analysis. The results also confirm the limited diversity present in cultivated C. arabica in Tanzania  相似文献   

14.
Six phenotypic characters and three withanolide markers were assessed in 25 accessions of Withania somnifera collected from different states of India for studying genetic variability. The variability ranges observed at phenotypic and chemotypic levels were polymorphic. Based on D2 values and PCA (Principal Component Analysis) of phenotypic traits like plant height, no. of branches/plant, no. of seeds/berry, root length, root diameter and root yield, these 25 accessions were grouped in five clusters. The relative contribution of each character towards genetic divergence was worked out. Five accessions–AGB002 (Rajasthan), AGB003 (J&K), AGB004 (Madhya Pradesh), AGB006 (J&K) and AGB009 (Punjab) representing clusters 2 and 4 exhibited maximum intra and inter-cluster divergence. Cluster 5 representing accession AGB053 (Andhra Pradesh) was having mixed traits. Chemically most of the accessions in cluster 3 showed uniformity in presence of three marker withanolides Withaferin A, Withanone and Withanolide A in the leaves.  相似文献   

15.
16.
Modeling how crop plants evolve under domestication requires estimating among-plant variation in important parameters of the reproductive system, including fecundity – the number of propagules produced – and propagule quality. Measuring these traits poses particular problems in vegetatively propagated crop plants. Unlike seeds, vegetative propagules are not intrinsic biological entities but are prepared by farmers. Propagule number and quality are thus determined by the interaction between plant traits and how farmers prepare propagules. We conducted observations, interviews and experiments to study this interaction in cassava grown by Makushi Amerindians, examining how both sources of variation, in plant traits and in farmers’ practices, combine to determine the number and quality of propagules produced. Increased stake mass, determined mostly by stem diameter, leads to increased yield and also to increased asexual ‘fecundity’ of the resulting plant. Farmers’ practices reflect knowledge of this relationship. Diameter is the key criterion in the selection of stems for stakes. Larger diameters are preferred; when thinner stems are used, stakes are cut longer, partially compensating for reduced mass. These results suggest that conscious and unconscious selection to increase ‘fecundity’ and propagule quality in cassava would act to favor plants with thicker stems. Mean stem diameter is greater, and variation in stem diameter is lower, in little-branched plants. Selection for increased asexual ‘fecundity’ can thus have led to reduction in the degree of branching, one of the most striking differences between domesticated cassava and its wild ancestors. Measuring variation in asexual fecundity is a key step in analyzing evolution of the mixed clonal/sexual reproductive systems that characterize many vegetatively propagated crop plants.  相似文献   

17.
The olive belongs to Olea, a complex genus and to a species with six subspecies. Subsp. europaea includes both the cultivated olive and the oleaster, the wild ancestor of the olive. Little is known on the phenotype of fruits from subsp. cuspidata. We aimed to compare europaea and cuspidata trees for oil content and composition and to verify whether natural hybrids may exist between the two subspecies. Specimens were from Kenya and putative natural hybrids between cuspidata and europaea were from Stellenbosch (South Africa). Cultivar and oleaster trees were sampled in France (continental and Corsica), Italy (Continental and Sardinia) and Tunisia. We have examined the fruit (drupe) structure between subsp. cuspidata and europaea and extracted oil from the pulp, seed and total drupe. Comparison for oil content was made between the cultivated olive and the oleaster and some cuspidata trees from Kenya. A few of cuspidata individuals from Botanical gardens do not enable phenotyping for oil content and composition. Oil composition analyses were performed for the main fatty acids to compare the three taxa. We used microsatellite markers at 11 loci to compute genetic distances between cuspidata, oleaster and cultivar trees and to reveal eventual hybrids. The SSR polymorphisms were huge between the two subspecies and they revealed that putative hybrids were true hybrids sampled around olive orchards. The whole comparison of oil content shows that olive cultivars display higher oil content than the subsp. cuspidata and that the oleaster trees are intermediate, whereas for oil composition of the drupe, cuspidata from Kenya shows less oleic acid than europaea. However, the cuspidata trees show seed oil composition similarities with the other two taxa. The discussion deals with possible reasons to explain the differences and of the possible uses of these taxa for breeding both the olive and brown olive. H. Hannachi and H. Sommerlatte have equal contribution in the article.  相似文献   

18.
Knowledge of habitat and feeding ecology is essential for developing an effective conservation management plan for threatened primates. Despite having been rediscovered nearly a decade ago, very little is known of the critically endangered cao vit gibbon (Nomascus nasutus) or its habitat. We analysed forest cover, made direct observations and conducted interviews of local elders to better understand forest changes and to determine the forest characters and species important to the survival of the gibbon. Interviews indicated human-induced forest resource exploitation focused on species-specific and larger trees most easily accessed. Gibbon forest habitat comprised four primary forest types. The mean canopy height over the whole site was 10.52 m. Gibbons consumed 81, or nearly half of the tree and liana species recorded in the site; however, only 19 species provide 77.8% of the diet. Six of the 19 food species were logged for different reasons throughout the history of the site. We conclude that effective conservation management of primates with highly limited distributions, focused dietary needs, and in degraded ecosystems will require active forest restoration, such as planting important food species in degraded sites.  相似文献   

19.
Butterfly pea, Clitoria ternatea is used in Africa as a companion crop and in the United States as an ornamental. The USDA, ARS, PGRCU curates 28 butterfly pea accessions. Butterfly pea accessions were transplanted from about 30-day-old seedlings to the field in Griffin, GA around 01 June 1999, 2003, 2006–2007 or directly sown in 2001. At 50% maturity, 19 accessions were characterized for morphology, phenology, and evaluated for regeneration. High quality plants regenerated from all accessions produced 6 to more than 3,400 total seeds. Butterfly pea can be successfully grown and regenerated in Griffin, GA. Coefficients of variation and principal component analysis revealed considerable variability among accessions for morphological and reproductive traits. Butterfly pea has potential to be used as a nutraceutical, pharmaceutical, or food. The flavonoid quercetin has been shown to reduce upper respiratory infections in humans while delphinidin and malvidin identified in butterfly pea flowers may inhibit various forms of cancer.  相似文献   

20.
A population viability analysis is important for the management of endangered populations and requires the estimation of survival parameters. The long-tailed bat (Chalinolobus tuberculatus) is one of only two native terrestrial mammals currently found in New Zealand and is classed as vulnerable. Its viability in temperate beech (Nothofagus) forest, Eglinton Valley, Fiordland, New Zealand was estimated using mark-recapture data collected between 1993 and 2003 using the Program MARK. Survival was estimated based on a total of 5286 captures representing 1026 individuals. Overall annual survival varied between 0.34 and 0.83 but varied significantly among three sub-populations and with sex and age. Females generally had a higher survival rate compared to males; and adults had higher survival relative to juveniles. Survival of all bats was lower in years when the number of introduced mammalian predators was high and when the winter temperature was warmer than average. High numbers of introduced predators occurred during three of the 10 years in the study. Climate change may mean that the conditions that promote high predator numbers may occur more frequently. A preliminary population viability analysis using a projection matrix on the overall adult female population showed an average 5% decline per year (λ = 0.95). Increased predator control targeting a range of predators is required in years when their numbers are high in order to halt the decline of this population of long-tailed bats. Population estimates using minimum number alive estimates supported the population estimates derived from Program MARK and a population viability analysis using matrices.  相似文献   

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