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1.
Detailed karyotypes and 4C DNA amounts have been studied in five cultivars of Cajanus cajan and 20 species belonging to Cajanus, Rhynchosia, Dunbaria, Flemingia and Paracalyx. C. cajan shows intraspecific variability and its karyotype is most similar to that of C. cajanifolius (sect. Cajanus) in the morphology and number of satellite chromosomes and the lack of any correlation between chromosome size within the complement and asymmetry. Karyotypes of C. lineatus and C. sericeus belonging to sect. Atylia are similar with respect to maximum r-index and the ratio of longest and shortest chromosomes in their respective complements. C. acutifolius (sect. Frutocosa) is distinct in having a very low ratio (1.44) between the longest and the shortest chromosomes, while in C. albicans, C. goensis, C. scarabaeoides (sect. Cantharospermum) there is no chromosome pair with r-index >2.0. C. mollis and C. volubilis (sect. Volubilis) show similarity with regard to ratio between the longest and the shortest chromosomes and a distinct chromosome pair with an arm ratio of 2.7 and C. platycarpus is distinct (sect. Rhynchosoides) in having the smallest ratio (1.36) between the longest and the shortest chromosomes. 4C DNA amounts in Cajanus and Rhynchosia vary between 3.28 pg to 11.69 pg and 4.92 pg to 11.13 pg respectively, while in Dunbaria, Flemingia and Paracalyx these vary between 4.70 and 7:06 pg. In the genus Cajanus karyotypic features and 4C DNA amounts agree with the sectional classification and bring out a close relationship between C. cajan and C. cajanifolius. This is supported by studies based on seed protein patterns, isozyme analysis, trypsin and chymotrypsin inhibitor patterns, RFLP and RAPD data and crossability relationships. A clear relation between DNA amount and abnormalities effecting the extent of pairing and recombination in interspecific hybrids shows the importance of this study in developing future breeding programme involving C. cajan and its wild relatives that are of potential value.  相似文献   

2.
Pigeonpea [Cajanus cajan (L.) Millsp.] is an important legume crop in South Asia, East and southern Africa, and the Caribbean. Pod fly (Melanagromyza obtusa Malloch) and pod wasp (Tanaostigmodes cajaninae La Salle) are important constraints to increase the production and productivity of pigeonpea under subsistence farming conditions. Host plant-resistance can be used as an important component for the management of these pests, and therefore, we evaluated 28 accessions of wild relatives of pigeonpea for resistance to these pests. There were significant inter- and intra-species differences in the relative susceptibility to pod fly and pod wasp damage. Accessions belonging to Cajanus scarabaeoides (L.) Thouars, C. sericeus (Benth. ex Bak.) van der Maesen, Rhynchosia bracteata Benth. ex Bak., C. acutifolius (F.v. Muell.) van der Maesen, C. lineatus (W. & A.) van der Maesen, and C. albicans (W. & A.) van der Maesen showed resistance to pod fly damage, while those from C. platycarpus (Benth.) van der Maesen, C. cajanifolius (Haines) van der Maesen and R. aurea DC. were susceptible. For the pod wasp, some of the accessions from C. scarabaeoides, C. albicans, Flemingia stricta Roxb., and R. bracteata (Roxb.) Wight showed a resistant reaction, while ICPW 83 belonging to C. scarabaeoides showed a susceptible reaction. ICPW 141, ICPW 278, and ICPW 280 (C. scarabaeoides), ICPW 214 (R. bracteata), ICPW 14 (C. albicans), and ICPW 202 (F. stricta) showed resistance to both pod fly and pod wasp damage. There was considerable variation in accessions belonging to different species for their susceptibility to pod fly and pod wasp, which can be exploited to breed for resistance to these pests. There was a negative association between pod wasp and pod borer damage, and therefore, it is important to keep track of the relative susceptibility of pigeonpea genotypes to pod wasp, while breeding for resistance to pod borers.  相似文献   

3.
The comparative morphology of the seeds of three Australian Citrus species, C. australasica C. inodora and C. garrawayi, was studied. Their seed characteristics were broadly similar to those of the cultivated species of the genus, when observed under light and scanning electron microscopy. Citrus garrawayi differed in seed shape (rounded to triangular) and seed coat morphology (i.e., thicker with longer epidermal protrusions) from C. australasica and C. inodora (rounded surface with flat underside in shape). The well-developed minute epidermal protrusions on the seed coat of C. garrawayi were more similar to those in the cultivated species, C. × sinensis and C. × aurantium. In contrast, the surface topography of C. australasica and C. inodora seeds was more like that of the cultivated species, C. × aurantifolia and C. × limon. Seed morphology, especially surface topography, was found to be a useful tool for taxonomic identification in Australian wild citrus.  相似文献   

4.
A total of 198 accessions representing 18 species of the genus Cajanus, assembled at the ICRISAT genebank, was characterized for 27 morpho-agronomic traits at ICRISAT farm, Patancheru, India. Newman–Keuls test of significance for mean values indicated significant differences among the species for one or more traits under study. Mean diversity for all traits was maximum in C. scarabaeoides (H′ = 0.590 ± 0.010). First three principal components (PCs) captured 84.3 % of total variation among all species. Cluster analysis resulted in three clusters. C. albicans and C. mollis formed Cluster 1; C. cajanifolius, C. crassus and C. platycarpus formed Cluster 2 and C. acutifolius, C. scarabaeoides, C. lineatus and C. sericeus formed Cluster 3. C. platycarpus for extra early flowering (34–40 days); C. scarabaeoides for early flowering (51–118 days); C. albicans for broad pods; C. mollis, C. albicans, C. cinereus for more seeds per pod (>6) and C. crassus, C. cajanifolius, C. mollis, C. platycarpus and C. albicans for high seed protein (>30 %) were found as promising sources. Long duration perennial species such as C. crassus, C. mollis and C. albicans are good sources for forage. Five accessions (ICP 15661, ICP 15664, ICP 15666, ICP 15668 and ICP 15671) of C. platycarpus, two accessions (ICP 15653 and ICP 15658) of C. mollis and one accession each of C. acutifolius (ICP 15611), C. albicans (ICP 15620), C. cajanifolius (ICP 15632), C. crassus (ICP 15768), C. lineatus (ICP 15646), C. scarabaeoides (ICP 15922) and C. sericeus (ICP 15760), found as promising for multiple trait combinations are useful in pigeonpea improvement programs.  相似文献   

5.
ABSTRACT

Common vetch (Vicia sativa L.) is an important legume cultivated for feed grain and forage in the Mediterranean and Central Asia regions. Little information is available about the changes in seed mass, chemical composition, and mineral concentration in the developing seeds of common vetch. Therefore, the objective of this experiment was to study the changes in seed mass, moisture content, fat, fiber, proteins, carbohydrates, reducing sugars, and macro- and microelements in common vetch seeds sampled at four pod developmental stages described based on pod color. Common vetch pods were harvested at four pod developmental stages: 1) full-size seed (FS), 2) greenish-yellow pods (GY), 3) yellow pods (Y), and 4) brown pods (B). Common vetch seeds attained maximum mass accumulation when pod color turned to yellow (the Y stage), which was a good indication of seed physiological maturity in common vetch. Results showed that ash, fat, fiber, protein, and carbohydrate content increased between the FS and GY stage. There was no significant change in the accumulation of these components at the Y stage as compared with the GY stage. During the desiccation phase (the Y to B stage), there was an increase in carbohydrate and reducing sugars and a decrease in proteins. Seed content (μg seed?1) of macro- and microelements levels increased as the seed matured, reaching the maximum level by the GY stage [for phosphorus (P), sodium (Na), zinc (Zn), and manganese (Mn)], the Y stage [for copper (Cu)], and the B stage [for potassium (K) and iron (Fe)]. These results suggest that the majority of seed chemical composition was accumulated by the GY stage where farmers can harvest common vetch seed without reducing seed mass and nutrient loss. These data serve as a useful characterization of changes in chemical composition based on pod developmental stages for further studies.  相似文献   

6.

Cotton (genus Gossypium) is an important agricultural crop around the world because of its fiber. Gossypium turneri Fryxell is a wild cotton species endemic to the state of Sonora (northwestern Mexico), whose status has been recently raised to endangered in the IUCN Red List. This species has invaluable characteristics that could be useful in the cultivated cotton gene pool. Despite its importance, G. turneri has been studied very little. To the best of our knowledge, no previous study has characterized its seed morphology and cytogenetics. Therefore, in the present study the seed morphology and karyotype of G. turneri were analyzed. Seeds of G. turneri have nonuniform oval shape and brown-gray color. This species produces short fibers attached to its seed surface that are not long enough for commercial use. Our seed sizes were greater than those previously described for G. turneri and other diploid cottons. The length and width of seeds were 8.80 mm and 4.83 mm, respectively. Traits such as embryo and seed coat were measured and carefully observed, and gossypol glands were observed only in the embryo during the evaluation of internal features of seeds. Cytogenetic analysis revealed 26 chromosomes (2n?=?2x?=?26) in mitotic cells of G. turneri. The karyotype analysis showed mainly metacentric (m), submetacentric (sm) and subtelocentric (st) chromosomes. Our results reveal important biological traits of G. turneri that could be considered in future studies to improve cultivated cotton.

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7.
Diversity in morphological characters of 206 accessions of 14 wild Vigna species from India was assessed. Of these, 12 species belonged to Asian Vigna in the subgenus Ceratotropis and two were V. vexillata and V. pilosa belonging to subgenus Plectotropis and Dolichovigna, respectively. Data on 71 morphological traits, both qualitative and quantitative, were recorded. Data on 45 qualitative and quantitative traits exhibiting higher variation were subjected to multivariate analysis for establishing species relationships and assessing the pattern of intraspecific variation. Of the three easily distinguishable groups in the subgenus Ceratotropis, all the species in mungo-radiata group, except V. khandalensis, viz. V. radiata var. sublobata, V. radiata var. setulosa, V. mungo var. silvestris and V. hainiana showed greater homology in vegetative morphology and growth habit. The species, however, differed in other plant, flower, pod and seed characteristics. Within species variation was higher in V. mungo var. silvestris populations and three distinct clusters could be identified in multivariate analysis. V. umbellata showed more similarity to V. dalzelliana than V. bourneae and V. minima in the angularis-umbellata (azuki bean) group. Within species variations was higher in V. umbellata than other species in the group. In the aconitifolia-trilobata (mothbean), V. trilobata populations, were more diverse than V. aconitifolia. The cultigens of the conspecific wild species were more robust in growth, with large vegetative parts and often of erect growth with three- to five-fold increase in seed size and seed weight, except V. aconitifolia, which has still retained the wild type morphology to a greater extent. More intensive collection, characterisation and conservation of species diversity and intraspecific variations, particularly of the close wild relatives of Asian Vigna with valuable characters such as resistance to biotic/abiotic stresses, more number of pod bearing clusters per plant etc. assumes great priority in crop improvement programmes.  相似文献   

8.
Inappropriate sulfur and potassium fertilization, particularly with continued soil nutrient mining and yearly fluctuations in rainfall, are major factors contributing to slow growth and low seed quality of canola in northwestern Pakistan. A field experiment was conducted in 2007–2008 on a sulfur (S) and potassium (K) deficient clay loam soil under irrigation at the research farm of NWFP (Northwest Frontier Province) Agricultural University, Peshawar, Pakistan, with an objective to determine response of phenology and seed quality of Brassica oilseed rape versus mustard to S and K fertilizer application. Twenty treatments in a randomized complete block design were consisted of two oilseed genotypes [rape (B. napus canola) and mustard (B. juncea canola)], at three rates each of S (15, 30, and 45 kg S ha?1) and K (30, 60, and 90 kg K ha?1), plus control (no K and S applied). Days to flowering, pod formation, seed filling duration and maturity were enhanced with K and S fertilization compared to control plots. The species B. napus took more time to flowering, pod formation, seed filling duration and maturity compared to B. juncea. Both genotypes responded positively for seed quality (oil and protein content) to K and S fertilization, but the magnitude of response varied with level and combination of K and S fertilization. Delay in the phenological stages showed negative relationship with oil and protein content in seed of both genotypes. It is concluded that a combination of 60 kg K ha?1 + 30 kg S ha?1 would accelerate phenological development and improve seed quality of rape and mustard in the study area.  相似文献   

9.
ABSTRACT

In this study, effects of foliar boron treatments on yield and yield components of fenugreek plants were assessed with the aid of principal component analysis (PCA) analysis. Experiments were conducted over the experimental fields of Erciyes University Agricultural Research and Implementation Center during the summer growing seasons of the years 2017 and 2018. Gürarslan fenugreek variety was used as the plant material of the experiments. Four different foliar boron (H3BO3) doses (control, 100, 200, 400, and 800 mg lt?1) were applied to fenugreek plants. Plant height, number of branches per plant, number of pods per plant, number of seeds per pod, pod length, the first pod height, thousand-seed weight, biological yield, seed yield, and harvest index were measured. Variance analysis revealed that only the seed yield of 2017 was significant (p < .05) and the other parameters were not found to be significant (p > .05). PCA analysis was performed to classify and characterize boron doses based on yield and yield components of fenugreek plants. PC1 and PC2 explained about 82% in total variation in 2017 and about 83% in 2018. In both years of the experiments, the greatest biological and seed yields were obtained from 800 mg lt?1 boron treatments. Therefore, 800 mg B lt?1 was recommended to get high seed yield from fenugreek plants.  相似文献   

10.
Acacia tortilis (Forsk.) Hayne ssp. raddiana (Savi) Brenan (Family Fabaceae; subfamily Mimosoideae) is a pioneer tree of dry areas. In spite of its several uses, there are no any published studies which deal with genetic diversity of Acacia tortilis (Forsk.) Hayne ssp. raddiana (Savi) Brenan in Tunisia. For this reason, here we study its genetic diversity with morphometric (only in Tunisian populations), chromosome counting, and cytometric (in Tunisian and Ziambabwean populations) approaches. Morphological field studies of four Tunisian populations (Bouhedma, Haddej, Hajeb and Gtar, respectively, designated as A, B, C, D) of A. tortilis (Forsk.) Hayne ssp. raddiana (Savi) Brenan using a general linear model (ANOVA) revealed statistically highly-significant differences between populations for all examined characters (P < 0.0001). Significant differences were found also between genotypes for the majority of morphological traits (P < 0.0001) except the width of 10 pods (laP), weight of 10 pods (Wt) and seed number of 10 pods (Sn) (P ≥ 0.110). The variability in the tree, pod and seed characters can be exploited for agro-industrial purposes. The DNA amount and chromosome numbers of populations Umguza and Gwaii River from Ziambabwe and of Tunisian populations A, B, C and D were determined. Tunisian populations had 2C nuclear DNA contents of 2.95–3.03 pg, and were shown to be tetraploid (2n = 4x = 52), whilst the two Ziambabwean populations had 1.39–1.40 pg and were diploid (2n = 2x = 26). It is suggested that the Tunisian populations are paleotetraploids, adapted to the more-arid local conditions.  相似文献   

11.
12.
13.
Crambe abyssinica Hochst. ex R.E. Fries (n = 45) is an industrial oilseed crop that is high in erucic acid. It is most closely related to C. hispanica L. (n = 30) and C. glabrata DC. (n = 15), although the latter species is most often included in the synonymy of C. hispanica. The species complex extends throughout the Mediterranean region, Ethiopia and East Africa. Crambe abyssinica is endemic to Ethiopia, C. glabrata to Spain, Portugal and Morocco, and C. hispanica is distributed in the Mediterranean region and Middle East. The present study compared genetic relationships among C. abyssinica, C. hispanica and C. glabrata and attempted a taxonomic separation of them using traditional morphological traits, agronomic and seed quality data, chromosome number, and various molecular data sets including nuclear-DNA based RAPD data, chloroplast (cpDNA) restriction site data and ITS sequence data for the internal transcribed spacer region of the nuclear ribosomal DNA. The three species can be distinguished most reliably by chromosome number. Accessions could generally, but not always, be distinguished morphologically by plant branching pattern, fruit articulation and colour, leaf pubescence and leaf shape. cpDNA restriction site data and ITS sequence data, two relatively conserved DNA data sets, supported the recognition of C. glabrata as a distinct species separate from the C. hispanica/C. abyssinica accessions. Within the latter group, both RAPD data and field evaluation data revealed greater amounts of genetic variation in C. hispanica compared with accessions of C. abyssinica, with the latter included as a subset of C. hispanica. Crambe glabrata was genetically distinct for all data sets and warrants separate species status.  相似文献   

14.
Sample populations of 157 Cannabis accessions of diverse geographic origin were surveyed for allozyme variation at 17 gene loci. The frequencies of 52 alleles were subjected to principal components analysis. A scatter plot revealed two major groups of accessions. The sativa gene pool includes fiber/seed landraces from Europe, Asia Minor, and Central Asia, and ruderal populations from Eastern Europe. The indica gene pool includes fiber/seed landraces from eastern Asia, narrow-leafleted drug strains from southern Asia, Africa, and Latin America, wide-leafleted drug strains from Afghanistan and Pakistan, and feral populations from India and Nepal. A third putative gene pool includes ruderal populations from Central Asia. None of the previous taxonomic concepts that were tested adequately circumscribe the sativa and indica gene pools. A polytypic concept of Cannabis is proposed, which recognizes three species, C. sativa, C. indica and C. ruderalis, and seven putative taxa.  相似文献   

15.
The genus Persea consists of two subgenera, Persea (known as avocados) and Eriodaphne (known as aguacatillos, avocado-like species). The present study aimed to determine whether the genus Persea is a monophyletic group and whether the division into two subgenera is an artificial one. In conjunction with these goals, a hypothesis of the phylogenetic relationships among Persea species is proposed. Our results suggest that Persea is not a monophyletic group. Two clades of Persea can be recognized. The results suggest that Eriodaphne and Persea should be considered to be independent genera. Various leaf and floral characters contributed for separation into groups. The definition of Eriodaphne is based on fruit color, sessile glands at the base of the stamens, vein prominence and leaf shape. Persea is more closely related to genera Nectandra and Ocotea than Eriodaphne. The 11 species included in Persea are recognized as species. The group is defined by fruit flavor, mature leaf color, number of tertiary divergent veins, and pubescent bracts in the inflorescence. Within this group, a clade of six species in which P. guatemalensis is included is recovered by seed shape, venation pattern relief, and number of fruits per cluster. Moreover, the seed shape supports the separation of P. floccosa and P. zentmyerii. A molecular character analysis is necessary to support the Persea clades proposed herein. Nevertheless the phylogenetic relationships revealed by this study provide new bases for the selection and conservation of the species Persea.  相似文献   

16.
Thirteen landraces of cowpea (Vigna unguiculata (L.) Walp. subsp. unguiculata cv. gr. Unguiculata) have been morphologically and agronomically characterised as part of a plan for safeguarding and protecting plant biodiversity typical of Lake Trasimeno (Umbria, central Italy). Sixty plants per accession were scored for plant vigour, growth habit, flower colour, days to flowering, days to first mature pod, pod length, total number of pods produced, seed colour pattern, 100 seed weight, total seed yield and virus susceptibility. With the exception of vigour and growth habit, all landraces appeared to be well differentiated from one another for all the characters considered. Strategies and problems related to their in situ conservation are discussed.  相似文献   

17.
The Sheanut tree (Vitellaria paradoxa C.F. Gaertn.) is highly valued for oil obtained from its seeds and frequently maintained in the semi-arid parklands of sub-Saharan Africa from Senegal to Uganda. Although variation has been noted for V. paradoxa subsp. paradoxa, few studies have been undertaken on patterns of phenotypic or genotypic diversity. Results are presented from 294 accessions collected in Ghana, using easily quantifiable morphological parameters. Productive mature trees varied from shrubby multi-stemmed individuals (height <5 m) to 30-m straight-boled trees with high compact canopies. The leaf lamina (tree mean ±% coefficient of variation of total mean) varied from 9.2 to 22.5 cm (±15.0%); seed length from 1.74 to 3.74 cm (±11.7%); and fat content from 29.1 to 61.9% of dry kernel weight (±9.4%). Clinal trends significantly correlated with location parameters that in turn related to environmental variation. Population variation of seed characteristics increased to the Northeast, perpendicular to the annual movement of the inter-tropical convergence zone. It is proposed that this is a consequence of past climatic changes, coupled with a lack of methodical selection for seed type when trees are maintained on agricultural land. Isozyme analysis revealed moderate to high levels of heterozygosity (He 0.2142) and high geneflow (Fst = 0.0124, Nm = 19.9), supporting results obtained from morphological studies. Isozyme and multivariate morphology analyses showed similar but weak geographical separation patterns.  相似文献   

18.
Fifty-five Greek Vicia faba L. populations, collected from diverse areas, were planted at two dry and low fertility sites for evaluation and classification. Yield evaluation, which was carried out by Principal Component Analysis (PCA) on the basis of seven yield traits, showed the number of pods per plant, number of ovules and seeds per pod, and branching from the basal nodes to be the most important traits for population evaluation regarding yield. For population classification, four dissimilarity coefficients (Manhattan, Average Taxonomic Distance, Euclidean distance and squared Euclidean distance) and four multivariate methods (PCA, UPGMA, Neighbor-joining and Principal Coordinate Analysis) were evaluated using fifteen morphological and seven yield traits. Neighbor-joining was chosen as the most suitable multivariate method. This method combined with PCA for the seven yield traits, placed the populations into six groups. As revealed by the application of PCA on all twenty-two traits the grouping was based mainly on pod characteristics, stem thickness, plant height, 1000 seed weight and branching from basal nodes. Based on the results of the present study, a model is proposed for conserving cross-pollinated species, such as faba bean.  相似文献   

19.
Wild species of safflower, Carthamus oxyacanthus Bieb., is highly crossable with cultivated species, C. tinctorius L. and could be directly exploited in broadening safflower gene pool and improving the crop for biotic and abiotic stress environments. In this study, genetic diversity among accessions of C. oxyacanthus and their relationships with cultivated safflower were evaluated using agro-morphological traits and polymorphic inter-simple sequence repeats (ISSR) markers. Significant variation was observed among accessions particularly for seeds per capitulum, seed yield per plant, harvest index and capitula per plant. Cluster analysis based on agro-morphological traits classified the wild accessions in two groups according to their geographical regions, and separated them from the cultivated genotypes. ISSR marker also revealed a high genetic variation among the accessions, and cluster analysis based on this marker divided genotypes into four groups, with cultivated ones in a separate clade. Genetic variation observed among the wild safflower germplasm at the DNA level was higher than the agro-morphological traits, indicating that ISSR is an effective marker system for detecting diversity among safflower genotypes and their genetic relationships. Accessions of C. oxyacanthus with high genetic relationship to cultivated species could be used for interspecific hybridization in breeding programs of safflower.  相似文献   

20.
Variability studies were carried out among different accessions of Argyrolobium roseum for 12 metric traits under natural and cultivated conditions. Almost all characters showed higher values in cultivated than natural population. Leaf breadth recorded highest CV (30.59%). Highest percentage of vitexin and D-pinitol (0.208 and 0.773% dwb) was observed in RAR-7 and RAR-6, respectively, under cultivated conditions. Phenotypic coefficient was higher than genotypic coefficient of variation. The association analysis revealed that root yield had positive significant correlation with 100 seed weight (r=0.839) biomass yield (r=0.601), where biomass yield had a positive significant correlation with leaf length, single pod weight. High heritability (97.4–99.8%) coupled with moderate genetic advance ranged between (49–67%) as a percent of mean was observed for leaf breadth, pod length, total foliage biomass yield and total root yield/plant. This suggests that direct selection for these traits is suitable for the improvement of this crop.  相似文献   

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