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1.
Cucumis silentvalleyi (Manilal, T. Sabu et P.J. Mathew) Ghebretinsae et Thulin and Cucumis indicus Ghebretinsae et Thulin are two rare narrow endemics of Western Ghats of India. Both have morphological resemblance but distinguishable by a few key characters like shape of the leaf, ovary and fruit, and chromosome number. While both are edible and non-bitter, their distribution is mutually exclusive, but overlapping with Cucumis sativus var. hardwickii (Royle) Alef. (the wild and feral form of C. sativus L.). Interspecific crossability studies indicate that both are related to each other and to a lesser extent to Cucumis setosus Cogn. and Cucumis melo L. Being incompletely described, a comparative account of their morphology, phenology, distribution, ecology and conservation are provided.  相似文献   

2.
Recent research point to the Indian wild taxa of Cucumis callosus (Rottler) Cogn. as the wild progenitor of melon (C. melo L.). Overlapping distribution with cultivated and weedy and feral forms of melo and normal fertility of F1 and BC1 generations of its cross with cultivated melon indicate its progenitor status. A perusal of herbarium data indicate its natural distribution pattern in the region comprising Vindhya Hills and Aravalli mountain ranges extending northwards to Indo-Gangetic plains and southwards to the Deccan plateau touching rain shadow areas of Western Ghats. Characterised by drought tolerance and field resistance to a host of pests and diseases, it is conspicuously absent in the high rainfall areas of Western Ghats and upper Himalayan region. Based on its morphological distinction and F1 and BC1 fertility with C. melo, a subspecific rank within C. melo is postulated. First-hand information on its occurrence, distribution and crossability relationship with other Indian taxa of Cucumis are given.  相似文献   

3.
Cucumbers (Cucumis sativus) are considered to be native to India. The germplasm of cultivated and wild relatives is shown to grow in very diverse agroecological conditions of the country. The north-eastern region is shown to nold special significance for wild and cultivated germplasm. The disease and specific adaptation characters are bionted out. Future scope for commercial growing and research needs are emphasised.  相似文献   

4.
A cucurbit species named Praecitrullus fistulosus (Stocks) Pangalo, which thrives in India, is considered to be a distant relative of watermelon. Recent experiments indicated that it has mild resistance to whiteflies (Bemisia tabaci). However, our attempts to cross various US plant introductions (PIs) of P. fistulosus with watermelon or other Citrullus PIs have not been successful. Thus, to determine genetic relatedness among those species, phylogenetic analysis [based on simple sequence repeat (SSR)–anchored (also termed ISSR), and randomly amplified polymorphic DNA (RAPD) markers] was conducted among PIs of P. fistulosus, Citrullus lanatus var. lanatus (watermelon), C. lanatus var. citroides and the wild Citrullus colocynthis. Phylogenetic relationships were also examined with Cucumis melo (melon), Cucumis sativus (cucumber), and wild Cucumis species including C. africanus, C. metuliferus, C. anguria, C. meeusei, and C. zeyheri. Wide genetic distance exists between Citrullus and Cucumis groups (8% genetic similarity). Phylogenetic relationships among Citrullus species and subspecies are closer (25–55% genetic similarity) as compared with those among most Cucumis species (14–68% genetic similarity). P. fistulosus appeared to be distant from both Cucumis and Citrullus species (genetic similarity between P. fistulosus and Cucumis or Citrullus groups is less than 3%). Although wide genetic differences and reproductive barriers exist among cucurbit species examined in this study, they are still considered as potential germplasm source for enhancing watermelon and melon crops using traditional breeding and biotechnology procedures.  相似文献   

5.
6.
Feeding trials were carried out to assess the ability of a giant vampyrellid soil amoeba to attack and lyse spores of fungi. Of 24 species of fungi studies, 15 were perforated in the same manner as was reported for Cochliobolus sativus. This giant amoeba is nutritionally versatile and can feed on bacteria, flagellates, blue green algae, diatoms and nematodes. Seven other soil amoebae failed to lyse conidia of C. sativus.  相似文献   

7.
Northeast India is rich in Citrus genetic diversity representing several wild and cultivated species. Besides commercially cultivated species, several wild, semi-wild and domesticated species namely Citrus indica, C. macroptera, C. ichangensis, C. latipes, C. megaloxycarpa and C. assamensis are found to grow in Northeast India. These species have great potential in improvement of Indian Citrus industry being source of genes for combating biotic and abiotic stresses. The natural diversity of these genetic resources is shrinking at alarming rate due to large scale deforestation, shifting cultivation practiced in these areas and climate change scenario in this important hotspot of biodiversity. Socio-economic importance of each species have been studied during surveys and interesting domestication trends were observed based on their cultural and economic significance, which led to “in situ on farm” conservation of C. indica, C. macroptera and threat to C. megaloxycarpa and C. ichangensis. Consequently, genetic resources of most of these species are facing severe threat of extinction necessitating policy interventions and adoption of dynamic conservation and management strategies. Species specific conservation strategy especially through “in situ on farm” conservation has been proposed with suitable sites in Northeastern Indian states based on population structure and suitability of habitat. Farmers’ support through “The Biological Diversity Act, 2002” and “The Protection of Plant Varieties and Farmers’ Rights Act, 2001” of India would bring the required impact on management of these complex genetic resources of Citrus. In the present study, we have documented the current status, socio-economic potential, domestication trends and associated traditional knowledge of these wild and semi-wild Citrus species occurring in Northeast India and enumerated suitable conservation strategies and desired policy interventions for their dynamic conservation and sustainable utilization.  相似文献   

8.
Total seed storage protein of 9 accessions of cultivated C. cajan and 10 wild Cajanus species was reported and compared by sodium dodecyl sulphate polyacrylamide gel electrophoresis. A considerable variation was detected among the protein profiles of different accessions of C. cajan while those of wild species were very specific and distinctly different from each other. Relative similarities between various taxa were estimated by Jaccard's similarity index and cluster analysis was performed to produce a UPGMA dendrogram. The clustering of 10 wild species and C. cajan more or less agrees with their sectional classification and available data based on morphological characteristics, crossability, genome pairing in hybrids and nuclear RFLPs. The species closest to C. cajan is C. cajanifolia although the accessions of C. cajan also share some bands present in the profiles of C. scarabaeoides, C. goensis, C. lineatus, C. acutifolius and C. volubilis. This points towards polyphyletic origin of the cultigen which has been discussed in this paper.  相似文献   

9.
Genetic relationships among 88 accessions from nine of the dozen species of Cucurbita (Cucurbitaceae) were assessed from polymorphisms at 74 SSR (simple sequence repeat) loci originating from C. pepo and C. moschata, yielding a total of 315 alleles distributed among 17 linkage groups, with an average of 4.3 alleles per locus. Genetic distance (GD) values were calculated, a principal coordinate analysis conducted, and a dendrogram constructed. Average within-species genetic distance values ranged from 0.07 for C. ecuadorensis and C. ficifolia to 0.46 for C. pepo. Each species was clearly defined, as all mean within-species GD values were lower than the respective mean between-species GD values. C. okeechobeensis had the most central position in the genus Cucurbita, with the lowest average GD to the other species, 0.61. C. foetidissima, the only xerophytic species examined, was the most distant, with a mean GD of 0.73 to the other species. C. pepo and C. ficifolia were the most outlying of the mesophytic species. Mean across-species GDs generally corresponded with crossability. However, there were some outstandingly low GD values between particular accessions of Cucurbita pepo, the economically most important species, and disease-resistant wild species, particularly C. okeechobeensis but also C. foetidissima. The results suggest that more intensive search and collection of C. okeechobeensis populations would likely yield genotypes that are more compatible with C. pepo. Moreover, successful application of genetic resources in the genus Cucurbita might be facilitated by using GD values obtained from SSR polymorphisms as a guide in choosing parents for interspecific crossing.  相似文献   

10.
Citrus indica and C. macroptera are the wild endangered species of Citrus occurring in northeastern India. Surveys were undertaken in this region for ascertaining distribution, studying variability and for collection of germplasm of these two species. C. indica, an endemic species of this region, was collected from the Citrus Gene Sanctuary located in buffer zone of Nokrek Biosphere Reserve in the Garo hills of Meghalaya. In addition, a putative natural hybrid of C. indica and C. limon was collected for the first time from the south Garo hills. C. macroptera had much wider distribution and was collected from Mizoram and Meghalaya states. In Jantia hills of Meghalaya, natural populations of this species are in a highly threatened state. The two species were unevenly distributed all over the explored territory. Morphological characterization of leaves, fruits and seeds indicated the presence of sizable variability within collected accessions of these two Citrus species. Indigenous technical knowledge gathered on the use and socio-economic importance indicated commercial potential for these two species in northeastern India. However, lack of cultivation of these species and clearing of forest cover at an alarming rate has led to an urgent need to adopt complementary conservation strategies to safeguard these species and to ensure their availability for future utilization. A major emphasis on developing methods for their propagation, multiplication and regeneration in in situ and ex situ conditions is required.  相似文献   

11.
Immature fruits of cultivated species of Luffa are commonly used as summer vegetable in India. Rich morphological variability occurs in cultivated species of Luffa in different growing regions of the country. To study morphological variability in cultivated and wild Luffa from different agro-ecological regions of India, a total of seventy accessions were assembled. Morphological variations in leaf, fruit and seed characters were found to delimit cultivated and wild Luffa species. Cluster analysis revealed two major clusters, one comprising of 36 accessions of Luffa acutangula and the other of 30 accessions belonging to L. aegyptiaca. A local cultivar “Satputia” (L. hermaphrodita) was classified along with cultivated L. acutangula and wild L. acutangula var. amara. Wild species namely L. graveolens and L. echinata were clustered closer to the L. acutangula.  相似文献   

12.
The object of the study comprised 54 grass pea (Lathyrus sativus) accessions originating from Czech Republic, Hungary, Slovak Republic, Poland, Ukraine and Russia together with 18 red pea (Lathyrus cicera) accessions from Greece, Spain and Italy. The plants were grown under the same conditions in Poland. Some phenological and morphological traits of plants as well as some seed morphological properties and nutritive value were investigated. Lathyrus sativus seeds contained more protein (average 300?g vs. 255?g?kg?1 dry matter (DM)), whereas the differences in the average contents of the other basic nutrients between both these species as well as between particular accessions were not substantial. Except for a low level of methionine, the protein of both species showed fairly high concentration of other exogenic amino acids (EAAI around 63–64%). Fat of both L. sativus and L. cicera seeds was found to contain a high level of polyunsaturated fatty acids (66.9 and 58.6%, respectively), mainly linoleic (57.4 and 47.2%, respectively). The researched L. sativus accessions had a quite low level of β-ODAP (733?mg with a range of 0.583–1.340?mg?kg?1 DM). Slightly higher content of this ANF (1,168?mg with 911–1,349?mg?kg ?1 DM) in L. cicera seeds was noted. Average tannin concentration in the L. sativus and L. cicera accessions reached 3.3 and 6.4?g?kg?1 DM, respectively. Average content of this ANF in L. sativus significantly correlated with the colour of both, flowers and seeds; with generally, a darker colour associated with higher levels of tannins.  相似文献   

13.
The North East India houses around 130 ethnic tribal communities which exhibits unique tradition, dialect and culture. These communities collect edible plants from wild forming a common practice for livelihood and subsistence even today. Of the varieties of plant consumed, ferns and fern–allies also constitute an important food supplement. An inventory survey was conducted in order to assess the wild edible ferns and fern–allies which are used as vegetables by various ethnic communities of North East India. Altogether, twenty-three (23) ferns and fern–allies are found to be edible, and used in preparing various cuisines. Four species viz. Diplazium esculentum (Retz.) Sw., Huperzia phlegmaria (L.) Rothm., Huperzia squarrosa (G. Forst.) Trevis. and Nephrolepis cordifolia (L.) C. Presl were cultivated in small scale for consumption and horticultural purposes, while the rest of the species were directly harvested from wild habitat. Role of these ferns in local cuisines, other reported uses and bioactive components were discussed. The study also emphasises on future development of ferns and its allies as potential vegetables in North East India.  相似文献   

14.
About 90% of chickpea (Cicer arietinum L.) in the world is grown under rainfed conditions where drought is one of the major constraints limiting its productivity. Unlike the cultivated chickpea, wild Cicer species possesses sources of resistance to multiple stresses; we therefore evaluated perennial wild Cicer species for resistance to drought. C. anatolicum, C. microphyllum, C. montbretii, C. oxydon and C. songaricum were compared with special checks; C. echinospermum, C. pinnatifidum and C. reticulatum and five cultivated chickpeas. After the cultivated chickpeas were killed, accessions were evaluated using a 1–5 scale, where 1 = highly drought resistant (no visible drought effect and full recovery after three successive wiltings) and 5 = highly drought susceptible (leaves and branches dried out, no recovery at all). All accessions of perennial wild Cicer species were significantly superior to those annual wild species and the cultivated chickpeas including the best drought tolerant chickpea, ICC 4958 under drought conditions. Perennial wild Cicer species did not only recover after wilting and drying out above ground level, they also tolerated high temperatures up to 41.8°C. But, they do not cross with the cultivated chickpeas. C. anatolicum should be taken account in long term breeding programs because it has closer affinities to the first crossability group than the others.  相似文献   

15.
A study was undertaken to know the difference/diversity between pigeonpea and its closely related wild species C. cajanifolius by studying their morphology, crossability, cytology of the hybrid between the two, and molecular studies. Studies revealed that there are at least 5–6 traits that separate the two species such as flower morphology, pod color and morphology, pod constriction, seed color and strophiole, 100 seed weight that separate C. cajan from C. cajanifolius. Molecular studies revealed that a genetic dissimilarity index value ranging from 0.81 to 0.94 exists between the two species.  相似文献   

16.
Crop wild relatives (CWR) have recently received significant attention due to their value as plant genetic resources and their contribution to world food security. We present a prioritized checklist of CWR in Spain in which the criteria of crossability with crops of economic importance, endemicity and threat status have been taken into account. First, we selected a list of genera corresponding to the most relevant crops for Spain and at the international level. These crops were classified into use categories (Food, Forage & Fodder, Ornamental, and Industrial & Other uses) depending on their main use. The wild plant species native to Spain belonging to these genera were then listed. After evaluation by national experts in plant breeding, the resulting checklist contained 929 species. Further selection based on crossability, endemicity and threat status led to the generation of the Prioritized Spanish Checklist of crop wild relatives containing 578 species. Thirty-two percent of these species belong to the Forage & Fodder use category, 28% to the Ornamental category, 24% to the Food category and 16% to the Industrial & Other uses category. Thirty-five percent of the prioritized species are endemic to Spain, and over one-fourth are classified under some category of threat according to the International Union for Conservation of Nature. Endemicity and threat status rates in the Prioritized Spanish Checklist of CWR were higher than those found in the prioritized CWR inventories of other countries. A ex situ assessment reporting number of accessions showed that 70% of the prioritized Spanish CWR have accessions preserved in genebanks.  相似文献   

17.
18.
Chrysanthemum is one of the most important and popular ornamentals over the world. Breeding of new pedigrees depends mainly on conventional crossing. Chrysanthemum genetic resources were categorized into three groups. Here we introduce the wild species and related genera of Chrysanthemum in order to extend the genetic resources that can be used for genetic improvement of chrysanthemums by hybridization. In the genus Chrysanthemum and closely related genera, there are many wild species that are able to cross successfully with modern chrysanthemums. These represent important genetic resources for introducing new characters into florist’s chrysanthemums. The genus Chrysanthemum consists of more than 40 species distributed mainly in East Asia. More than 20 species of Chrysanthemum are native to China. Unfortunately, little of this information has been published in western languages. In this paper, we also provide an overall review of the basic information of the wild species of we have collected in China in order to understand and exploit those genetic resources much better. We have collected about 17 wild species and studied their useful characters in the past several years. These species include C. oreastrum (Hance) Y. Ling, C. hypargyrum (Diels) Y. Ling et C. Shih, C. zawadskii (Herbert) Tzvelev, C. chanetii (H. Léveillé) C. Shih, C. naktongense (Nakai) Tzvelev, C. mongolicum (Y. Ling) Tzvelev, C. argyrophyllum (Y. Ling) Y. Ling et C. Shih, C. rhombifolium (Hemsley) Y. Ling, C. vestitum (Hemsley) Y. Ling, C. dichrum C. Shih, C. glabriusculum (W. W. Smith) C. Shih, C. indicum (Linnaeus) Des Moulin, C. lavandulifolium (Fischer ex Trautvetter) Kitamura, C. foliaceum G. F. Peng, Shih et S. Q. Zhang, C. nankingense (Handel-Mazzetti) X. D. Cui, C. potentilloides (Handel-Mazzetti) C. Shih and C. maximowiczii (Komarov) Tzvelev. In addition to this genus, we have collected some species of the related genera including Brachanthemum mongolicum Krascheninnikov, B. pulvinatum (Handel-Mazzetti) C. Shih, B. gobicum Krasch, Ajania fastigiata (C. Winkler) Poljakov, A. achilleoides (Turczaninow) Poljakov ex Grubov, A. khartensis (Dunn) C. Shih, A. fruticulosa (Ledebour) Poljakov, A. pallasiana (Fischer ex Besser) Poljakov, Phaeostigma salicifolia (Mattf.) Muld., Elachanthemum intricatum (Franchet)Y. Ling et Y. R. Ling and two endemic species of Opisthopappus including O. taihangensis (Ling) Shih and O. longilobus Shih in China.  相似文献   

19.
Capsicum baccatum is one of five domesticated pepper species which, despite its morphological and ecological variability, has been underexploited for germplasm improvement. Utilizing a broad spectrum of domesticated and wild C. baccatum germplasm, we utilize AFLP markers to describe the species’ molecular diversity and population structure in the South American gene pool. Analysis of molecular variance (AMOVA) revealed greater genetic diversity in the wild form of C. baccatum (C. baccatum var. baccatum) than in the domesticated form of the species (C. baccatum var. pendulum). Both Bayesian and distance based clustering analysis, as well as principal coordinates analysis (PCA), concordantly demonstrated admixture/shared ancestry between wild and cultivated C. baccatum botanical varieties. Two principal genetic groups were identified in the domesticated C. baccatum accessions largely based on their geographic distribution in South America. One group was predominated by accessions from the western territories of the species’ distribution (Peru, Colombia, Ecuador, Bolivia, Chile and northwestern Argentina) and the second by accessions from the eastern regions, Paraguay and eastern Argentina). The two genetic groups overlapped in the geographic location of present-day Bolivia. The grouping pattern suggested that C. baccatum was domesticated in multiple sites and that its evolution took two lineages followed by lineage differentiation. The wild accessions most closely related to the cultigens were found in the highlands of Peru and Bolivia, which support the early hypothesis that this region is one of the domestication sites of this species. A Bayesian assignment analysis demonstrated that Brazilian wild forms of C. baccatum were genetically distant to all other accessions and made little to no contribution to the domesticated genepool. Moreover, results of clustering analysis suggested that C. baccatum likely originated from present day Paraguay. Analysis of inter-specific relationships across selected Capsicum species supported independent lineages for the two crossability groups within Capsicum, the baccatum species-complex (including C. baccatum) and the annuum species-complex (including C. annuum, C. chinense and C. frutescens). However, the results did not support taxonomic distinction of C. baccatum var. umbilicatum from C. baccatum var. pendulum. The present study provides new insights into the domestication of C. baccatum. The results will be useful for identifying accessions for crop improvement and guiding the development of in situ and ex situ conservation programs.  相似文献   

20.
The genetic diversity in genus Prunus is mainly confined to temperate regions of Himalaya and to a lesser extent in the sub-montane and hilly regions of peninsular India. The cultivated and wild species of Prunus have tremendous potential for improvement and utilization. This paper includes the genetic resources of cultivated and wild useful species of Prunus in India with emphasis on their distribution, potential traits/ useful characteristics and utilization. The information on potential genetic resources of Prunus would be helpful in collection, evaluation, conservation and utilization of species.  相似文献   

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