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1.
This study aimed to investigate the effect of inoculation with plant growth-promoting Rhizobium and Pseudomonas species on NaCl-affected maize. Two cultivars of maize (cv. Agaiti 2002 and cv. Av 4001) selected on the basis of their yield potential were grown in pots outdoors under natural conditions during July. Microorganisms were applied at seedling stage and salt stress was induced 21 days after sowing and maintained up to 50% flowering after 120 days of stress. The salt treatment caused a detrimental effect on growth and development of plants. Co-inoculation resulted in some positive adaptative responses of maize plants under salinity. The salt tolerance from inoculation was generally mediated by decreases in electrolyte leakage and in osmotic potential, an increase in osmoregulant (proline) production, maintenance of relative water content of leaves, and selective uptake of K ions. Generally, the microbial strain acted synergistically. However, under unstressed conditions, Rhizobium was more effective than Pseudomonas but under salt stress the favorable effect was observed even if some exceptions were also observed. The maize cv. Agaiti 2002 appeared to be more responsive to inoculation and was relatively less tolerant to salt compared to that of cv. Av 4001.  相似文献   

2.
Grains of 80 accessions of nine species of wild Triticum and Aegilops along with 15 semi-dwarf cultivars of bread and durum wheat grown over 2 years at Indian Institute of Technology, Roorkee, were analyzed for grain iron and zinc content. The bread and durum cultivars had very low content and little variability for both of these micronutrients. The related non-progenitor wild species with S, U and M genomes showed up to 3–4 folds higher iron and zinc content in their grains as compared to bread and durum wheat. For confirmation, two Ae. kotschyi Boiss. accessions were analyzed after ashing and were found to have more than 30% higher grain ash content than the wheat cultivars containing more than 75% higher iron and 60% higher zinc than that of wheat. There were highly significant differences for iron and zinc contents among various cultivars and wild relatives over both the years with very high broad sense heritability. There was a significantly high positive correlation between flag leaf iron and grain iron (r = 0.82) and flag leaf zinc and grain zinc (r = 0.92) content of the selected donors suggesting that the leaf analysis could be used for early selection for high iron and zinc content. ‘Chinese Spring’ (Ph I ) was used for inducing homoeologous chromosome pairing between Aegilops and wheat genomes and transferring these useful traits from the wild species to the elite wheat cultivars. A majority of the interspecific hybrids had higher leaf iron and zinc content than their wheat parents and equivalent or higher content than their Aegilops parents suggesting that the parental Aegilops donors possess a more efficient system for uptake and translocation of the micronutrients which could ultimately be utilized for wheat grain biofortification. Partially fertile to sterile BC1 derivatives with variable chromosomes of Aegilops species had also higher leaf iron and zinc content confirming the possibility of transfer of required variability. Some of the fertile BC1F3 and BC2F2 derivatives had as high grain ash and grain ash iron and zinc content as that of the donor Aegilops parent. Further work on backcrossing, selfing, selection of fertile derivatives, leaf and grain analyses for iron and zinc for developing biofortified bread and durum wheat cultivars is in progress. Nidhi Rawat, Vijay K. Tiwari, and Neelam Singh have contributed equally to the work.  相似文献   

3.
A fertile amphidiploid × Brassicoraphanus (RRCC, 2n = 36) between Raphanus sativus cv. HQ-04 (2n = 18, RR) and Brassica alboglabra Bailey (2n = 18, CC) was synthesized and successive selections for seed fertility were made from F4 to F10. F10 plants exhibited good fertility with 14.9 seeds per siliqua and 32.3 g seeds per plant. Cytological observation revealed that frequent secondary pairing occurred among 3 chromosome pairs in pollen mother cells of plants (F4) with lower fertility, but not of plants with high fertility (F10). GISH analysis indicated that these F10 plants included the expected 18 chromosomes from R. sativus and B. alboglabra, respectively, but they lost approximately 27.6% R. sativus and 35.6% B. alboglabra AFLP (amplified fragment length polymorphism) bands. The crossability of the Raphanobrassica with R. sativus and 5 Brassica species (13 cultivars) were investigated. Seeds or F1 seedlings were easy to be produced from crosses × Brassicoraphanus × R. sativus, and B. napus, B. juncea and B. carinata × Brassicoraphanus. Fewer seeds or seedlings were obtained from crosses × Brassicoraphanus × B. napus, B. juncea and B. carinata. However, few seeds were harvested in the reciprocals of × Brassicoraphanus with B. rapa and B. oleracea. The possible cause of fertility improvements and the potential of the present × Brassicoraphanus for breeding were discussed.  相似文献   

4.
About 65 years ago, more than 150 Swiss maize landraces (Zea mays L. ssp. mays) of the flint type were collected and conserved ex situ. Due to the climatically and culturally diverse environment of the Alps, a considerable genetic diversity of this material was assumed. To prove this, an efficient method was required to carry out genetic profiling of all the accessions in the Swiss Gene Bank. Simple sequence repeat marker (SSR) profiling in combination with the visualization of the polymerase chain reaction (PCR) products on agarose gels was chosen. Here a set of 19 different landrace accessions was analyzed to: (i) investigate their genetic diversity, (ii) investigate and display the population structure and (iii) determine whether DNA bulks rather than single plants can be used for such analyses. Four repeated samples of one accession were found to be much closer to one another than to the rest of accessions. Furthermore, specific alleles were identified for several accessions. The PCR products of the bulked DNA samples represented only a small part of the variation revealed by the analysis of individuals. Loci with four base repeat motifs performed better in the analysis of bulks than loci with other repeat motifs. The correlation between genetic distance matrices, based on the analysis of individuals and bulks, respectively, was significant. Thus, the single plant approach allowed for sufficient differentiation of accessions, and DNA bulks visualized on agarose gels led to correlated genetic distances although a limited number of alleles were detected. Although the limited resolution of agarose gels likely causes some bias, profiling of larger sets with the individual plant approach appears feasible and more informative compared to the bulk analysis we conducted.  相似文献   

5.
Neglected and underutilized species often play a vital role in securing food and livestock feed, income generation and energy needs of rural populations. In spite of their great potential little attention has been given to these species. This increases the possibility of genetic erosion which would further restrict the survival strategies of people in rural areas. Ziziphus spina-christi is a plant species that has edible fruits and a number of other beneficial applications that include the use of leaves as fodder, branches for fencing, wood as fuel, for construction and furniture making, and the utilization of different parts e.g. Fruits, leaves, roots and bark in folk medicine. Moreover, the plant is adapted to dry and hot climates which make it suitable for cultivation in an environment characterized by increasing degradation of land and water resources. Lack of research in Z. spina-christi hinders its successful improvement and promotion. Therefore, studies are needed to fully exploit this species. This article aims at summarizing information on different aspects of Z. spina-christi to stimulate interest in this crop which is of importance in Sudan and other countries of the semi-arid tropics.
Amina Sirag SaiedEmail:
  相似文献   

6.
Solanum pimpinellifolium, due to its close relationship to S. lycopersicum, has been a genetic source for many commercially important tomato traits. It is a wild species found in the coastal areas of Peru and Ecuador. In this study, the genetic variation of S. pimpinellifolium was studied using the diversity found in 10 microsatellites in 248 plants spread throughout its entire distribution area, including Ecuador, which has been underrepresented in previous studies. Peruvian and Ecuadorian accessions are genetically quite differentiated. A possible cause of these differences could be the non-uniform nature of the coastal Ecuadorian and Peruvian climates, seeing as an important correlation between genetic differentiation and climate has been found. In addition, Ecuadorian and south Peruvian accessions have a lower genetic diversity and a higher homozygosity due to their higher autogamy, lower population size, and possible colonization bottlenecks. The Galápagos Islands population is an extreme case, with no diversity, likely caused by a recent colonization from the northern continental Ecuadorian region where genetically identical plants have been found. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Elena Zuriaga and José M. Blanca contributed equally to this work.  相似文献   

7.
A pot experiment was conducted to evaluate the influence of pre-inoculation of cucumber plants with each of the three arbuscular mycorrhizal (AM) fungi Glomus intraradices, Glomus mosseae, and Glomus versiforme on reproduction of the root knot nematode Meloidogyne incognita. All three AM fungi tested significantly reduced the root galling index, which is the percentage of total roots forming galls. Numbers of galls per root system were significantly reduced only in the G. intraradices + M. incognita treatment. The number of eggs per root system was significantly decreased by AM fungus inoculation, no significant difference among the three AM fungal isolates. AM inoculation substantially decreased the number of females, the number of eggs g−1 root and of the number of eggs per egg mass. The number of egg masses g−1 root was greatly reduced by inoculation with G. mosseae or G. versiforme. By considering plant growth, nutrient uptake, and the suppression of M. incognita together, G. mosseae and G. versiforme were more effective than G. intraradices.  相似文献   

8.
Deforestation in southeast Brazil has led to the extinction of Hymenaea courbaril var. stilbocarpa and ex situ conservation has been established. In this study, the levels of genetic diversity and the effective population size of H. courbaril in a germplasm bank were investigated using six nuclear microsatellite loci. A total of 79 and 91 alleles were found in 65 seed-trees and their 176 offspring, respectively. Offspring have a higher average number of alleles per locus (= 15.2) than seed-trees (= 13.2), but lower observed heterozygosity (offspring: H o = 0.566; seed-trees: H o = 0.607). The estimate of outcrossing rate shows that the study population is perfectly outcrossed (t m  = 0.978, > 0.05). Significant deviations from random mating were detected through mating among relatives and correlated matings. The average variance in effective population size for each family was 2.63, with a total effective population size retained in the bank of 170.1. These results confirm that the preserved population of H. courbaril retains substantial genetic variability. Moacyr Antonio Mestriner and Ana Lilia Alzate-Marin—CEEFLORUSP Members.  相似文献   

9.
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   

10.
Root colonization and mitigation of NaCl stress on wheat seedlings were studied by inoculating seeds with Azospirillum lipoferum JA4ngfp15 tagged with the green fluorescent protein gene (gfp). Colonization of wheat roots under 80 and 160 mM NaCl stress was similar to root colonization with this bacterial species under non-saline conditions, that is, single cells and small aggregates were mainly located in the root hair zone. These salt concentrations had significant inhibitory effects on development of seedlings, but not on growth in culture of gfp-A. lipoferum JA4ngfp15. Reduced plant growth (height and dry weight of leaves and roots) under continuous irrigation with 160 mM NaCl was ameliorated by bacterial inoculation with gfp-A. lipoferum JA4ngfp15. Inoculation of plants subjected to continuous irrigation with 80 mM NaCl or to a single application of either NaCl concentration (80 or 160 mM NaCl) did not mitigate salt stress. This study indicates that, under high NaCl concentration, inoculation with modified A. lipoferum reduced the deleterious effects of NaCl; colonization patterns on roots were unaffected and the genetic marker did not induce undesirable effects on the interaction between the bacterium and the plants.  相似文献   

11.
Calamintha nepeta and Micromeria thymifolia have been traditionally used in the Mediterranean area as condiments and medicinal plants for a long time. Whereas in parts of Italy C. nepeta (special recipes have been developed in Lazio and Tuscany) is also an established garden plant showing different evolutionary products and their interaction among each other and the wild progenitor, M. thymifolia is being developed into a new crop plant. Both plants and their uses are described with regard to Italy. There is a marked tendency to broaden the use of condiments and spices which results in new crop plants which have to be documented and elaborated in further studies. Many species of Labiatae are predisposed to use by man and new items can be found even in areas which have to be considered as well studied.  相似文献   

12.
Two introduced wild species Helianthus annuus L. and H. petiolaris Nutt. have become widespread in central Argentina and overlap the sunflower crop region. Intermediate off-type plants between the wild and cultivated species are often found, which is of concern because of the recent release of imidazolinone resistant varieties and the likely use of genetically modified sunflower cultivars. The progeny of 33 off-type plants obtained from 14 representative sites of the diffusion area were studied to confirm hybrid origin. Germination, survival, morphological traits and days to flowering confirmed hybridization between crop and both wild species, when compared to eight accessions of typical wild plants. Some progenies were presumably crop–wild H. annuus hybrids, some originated from the cross of cultivated plants and H. petiolaris, and two were the advanced generation of a cultivated hybrid. Hence, morphological traits are a good clue for the identification of spontaneous hybrid plants at field. The results indicate that crop–wild hybridization and introgression occur at various places in central Argentina. This fact may represent a way to herbicide resistance escape and future transgene escape if GM sunflower cultivars are released for commercial use.  相似文献   

13.
Allanblackia parviflora A. Chev. (Clusiaceae Lindley) is an indigenous tree species which is found in the rain forest regions of Ghana. It is a potential candidate fruit tree species being introduced in agroforestry systems. Information on genetic diversity, reproductive biology and fruit yield are not known. Field expeditions to seven populations of Allanblackia parviflora in Ghana were undertaken in 2003–2006 during which fruits were collected from 109 trees for characterization. The species was found to be dioecious. The colour of flowers varied from whitish to reddish. No ecological differences in number of fruits per tree, fruit shape and seed health were observed. However, large variations in fruit size and shape were observed among individual trees sampled. A high heritability (h 2 = 0.822) in fruit size and genetic gain (G = 20.1%) in fruit size for selection of trees with above average fruit size were observed. A positive significant correlation was observed between fruit size and seed weight (R = 0.54, P < 0.05; Fig. 6). The results suggest that selection and cloning of trees with large fruits could lead to higher yield of seeds for oil production.  相似文献   

14.
The present study was conducted to isolate and characterize rhizobial strains from root nodules of cultivated legumes, i.e. chickpea, mungbean, pea and siratro. Preliminary characterization of these isolates was done on the basis of plant infectivity test, acetylene reduction assay, C-source utilization, phosphate solubilization, phytohormones and polysaccharide production. The plant infectivity test and acetylene reduction assay showed effective root nodule formation by all the isolates on their respective hosts, except for chickpea isolate Ca-18 that failed to infect its original host. All strains showed homology to a typical Rhizobium strain on the basis of growth pattern, C-source utilization and polysaccharide production. The strain Ca-18 was characterized by its phosphate solubilization and indole acetic acid (IAA) production. The genetic relationship of the six rhizobial strains was carried out by random amplified polymorphic DNA (RAPD) including a reference strain of Bradyrhizobium japonicum TAL-102. Analysis conducted with 60 primers discriminated between the strains of Rhizobium and Bradyrhizobium in two different clusters. One of the primers, OPB-5, yielded a unique RAPD pattern for the six strains and well discriminated the non-nodulating chickpea isolate Ca-18 from all the other nodulating rhizobial strains. Isolate Ca-18 showed the least homology of 15% and 18% with Rhizobium and Bradyrhizobium, respectively, and was probably not a (Brady)rhizobium strain. Partial 16S rRNA gene sequence analysis for MN-S, TAL-102 and Ca-18 strains showed 97% homology between MN-S and TAL-102 strains, supporting the view that they were strains of B. japonicum species. The non-infective isolate Ca-18 was 67% different from the other two strains and probably was an Agrobacterium strain.  相似文献   

15.
The karyomorphology for eight diploid species of Arachis belonging to three sections has been described for the first time, Sect. Extranervosae: A. macedoi (2n = 20m) and A. retusa (2n = 14m + 6sm); Sect. Heteranthae: A. sylvestris (2n = 16m + 4sm); Sect. Procumbentes: A. chiquitana (2n = 18m + 2sm); Sect. Arachis: A. cruziana (2n = 18m + 2sm), A. herzogii (2n = 18m + 2sm), A. simpsonii (2n = 20m) and A. williamsii (2n = 20m). A pair of satellited chromosomes was observed in all species. A chromosomes were found in A. chiquitana, A. herzogii and A. simpsonii. Karyotypic differences between sections were observed, but not enough to establish a characteristic karyotype pattern for each section. However, the species may be differentiated by the presence of A chromosomes, the type and position of satellites, and the karyotype formulae. These results are discussed with regard to karyotype evolution in Arachis to contribute to understanding the role of chromosome changes in the evolution of the genus.  相似文献   

16.
17.
Pandanus tectorius Parkinson ( P. fascicularis Lam.) of the family Pandanaceae constitutes one of the major bioresources of Ganjam coast, Orissa; used mainly in small scale perfume industry for aromatic compound extracted from the male inflorescences. In order to establish genetic diversity, if any related to perfume yield, samples of P. tectorius representing male populations from seven locations representing populations I–VII along the coastline of Orissa, India, were analysed for somatic chromosome number, 4C genomic DNA content, randomly amplified polymorphic DNA (RAPD) as well as phytochemicals. The somatic chromosome number in all the populations I–VII was 2n = 60. The chromosomes were of minute size without showing any remarkable structural variation. Like wise the average 4C DNA content was 5.09 pg (≅4,912 Mbp) that showed no intra- or inter-population differences. Out of 54 decamer primers tested, a total of 1,260 amplicons were obtained from 34 primers accounting 43.49% polymorphism. Molecular phylogenetic analysis of the seven populations revealed two distinct branches, with populations II and III in one and the rest populations in the other branch of the phylogenetic tree. It was important to note that the unique populations II and III confined to the Ganjam coast of Orissa having RAPD markers: OPA 09–940 bp, OPA 09–705 bp, OPC 14–1,500 bp, OPC 14–700 bp, OPC 20–1,475 bp, OPC 20–1,350 bp, OPC 20–920 bp and OPC 20–700 bp, were distinguished form the rest of the populations. The aforesaid populations (II and III) are well known to produce aroma of high quality and yield, composed of primarily phenyl ethyl methyl ether (66.8–83%) and terpinen-4-ol (5–12%) along with a number of other phyto-chemical compounds that support the flourishing perfume industry and livelihood of the local people in the region. The findings underscored the possible role of local eco-geography in contributing to the micro-evolution of unique high perfume yielding genotypes of P. tectorius that represented populations II and III at Ganjam coast, which were genetically distinct from the rest of the populations revealed by RAPD analysis.  相似文献   

18.
Simple sequence repeats (SSRs), highly dispersed nucleotide sequences in genomes, were used for germplasm analysis and estimation of the genetic relationship of the D-genome among 52 accessions of T. aestivum (AABBDD), Ae. tauschii (DtDt), Ae. cylindrica (CCDcDc) and Ae. crassa (MMDcr1Dcr1), collected from 13 different sites in Iran. A set of 21 microsatellite primers, from various locations on the seven D-genome chromosomes, revealed a high level of polymorphism. A total of 273 alleles were detected across all four species and the number of alleles per each microsatellite marker varied from 3 to 27. The highest genetic diversity occurred in Ae. tauschii followed by Ae. crassa, and the genetic distance was the smallest between Ae. tauschii and Ae. cylindrica. Data obtained in this study supports the view that genetic variability in the D-genome of hexaploid wheat is less than in Ae. tauschii. The highest number of unique alleles was observed within Ae. crassa accessions, indicating this species as a great potential source of novel genes for bread wheat improvement. Knowledge of genetic diversity in Aegilops species provides different levels of information which is important in the management of germplasm resources.  相似文献   

19.
Waxy maize is a special type of cultivated maize and has grown in China for long history. However, the evolution and origin of waxy maize still remain unknown. We analyzed the origin and evolution of waxy maize by sampling DNA sequences from four taxa with eight populations: waxy maize and other maize cultivars from Southwest China or America (Zea mays L. ssp. mays), parviglumis (Z. mays L. ssp. parviglumis Iltis et Doebley), three more distant species within this genus (Z. luxurians (Durieu et Ascherson) Bird, Zea perennis (Hitchcock) Reeves et Mangelsdorf, and Zea diploperennis Iltis, Doebley et Guzman), and a representative of sister genus (Tripsacum dactyloides L.). We sequenced 20 sequences and downloaded 26 sequences from NCBI for the glb1 locus, which encodes a nonessential seed storage protein. Within the Zea genus samples, the waxy maize has the minimum sequence diversity, which contains 31.1% of the level of diversity of parviglumis and 58.5% of the level of diversity of normal maize from Southwest China. Sequence variation within glb1 locus is consistent with neutral evolution in all four taxa according to Tajima’D test. From the NJ tree for glb1 sequences waxy maize formed two main groups which are intermixed with normal maize sequences. These results suggest that the Chinese waxy maize originate from a single gene mutation from normal maize. Combined with the history of maize dispersal in China we can even think that Chinese waxy maize was divergenced from Chinese flint maize.  相似文献   

20.
Lotus (Nelumbo nucifera Gaertn. ssp. nucifera), one of 12 aquatic species used as vegetable, has been cultivated for more than 2,000 years, and now has been widely cultivated in almost all provinces in China. The largest area under cultivation of lotus is located in the regions surrounding mid-down Yangtse River, including Hubei, Jiangsu, Zhejiang, Anhui, Jiangxi and Hunan provinces. According to different purposes or morphological differences, the Chinese lotus (N. nucifera ssp. nucifera) is usually classified into three types: rhizome lotus, seed lotus and flower lotus. Rhizome lotus is mainly cultivated in Hubei, Jiangsu, Anhui and Zhejiang provinces; Seed lotus in Jiangxi, Fujian and Hunan, and flower lotus in Wuhan, Hubei province, and Beijing. Up to the year 2002, a total of 572 lotus accessions (including landraces, cultivars and breeding lines) were conserved in National Garden of Aquatic Vegetable, Wuhan, Hubei province, including those collections from 153 counties in 18 provinces, and lines bred by breeders. Out of these accessions, 310 were rhizome lotus which contains 201 landraces and 109 breeding lines; 229 were flower lotus including 172 cultivars and 57 breeding lines; and the rest 33 were seed lotus with 18 cultivars.  相似文献   

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