首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 681 毫秒
1.
Anchote (Coccinia abyssinica) is plant endemic in Ethiopia with a high calcium content grown for its edible tuberous roots. In spite of its importance as food security crop, there is no information available on molecular genetic diversity of this crop. Therefore, the aim of this study was to assess genetic diversity within and among 12 populations of anchote using ISSR markers. Using nine ISSR primers, a total of 87 scorable bands was generated of which 74 were polymorphic. Within population diversity based on polymorphic bands ranged from 13.8 to 43.53 % with a mean of 33.05 %, Nei’s genetic diversity of 0.04–0.156 with a mean of 0.12, Shannon information index of 0.07–0.23 with a mean of 0.175 and analysis of molecular variation (AMOVA) of 51.4 % were detected. With all diversity parameters, the highest diversity was obtained from Gimbi, Bedele and Ale populations, whilst the lowest was from Manna. AMOVA showed a 48.56 % between populations variability and significantly lower than that of within population variation. Population differentiation with FST was 48.56 %. From Jaccard’s pairwise similarity coefficient, Decha and Nedjo were most related populations exhibiting 0.76 similarity and Manna and Nedjo were the most distantly related populations with similarity of 0.52. The only pentanucliotide primer used in the study, Primer 880 (GGAGA)3, showed a unique band in some individuals that appeared to be associated with morphological quantitative traits (lowest seed number, high protein content, largest fruit size and smallest vine length). Illubabor and Gimbi populations exhibited highest genetic diversity so that the populations should be considered as the primary sites in designing conservation areas for this crop.  相似文献   

2.
Soil salinity presents a serious threat to crop production. The relatively poor tolerance to this stress agent exhibited by conventional crops incentivizes the search for alternative producers of food and forage in salinity-affected environments. Halophytes belonging to the genus Salicornia L. have been suggested as being able to provide both forage and edible seed oil. Here, a set of 14 Salicornia europaea L. accessions was investigated for their ability to produce seed oil and forage in response to a range of salt concentrations (100, 300 and 600 mM NaCl) in the water used for irrigation. Seed of the accessions was collected from diverse sites close to saline rivers and the sea in Iran. Salinity was shown to have a major effect on biomass yield, and on seed oil yield and composition. The ratio of unsaturated to saturated fatty acids in the seed oil was remarkably high. Forage yield was highest when irrigated with 300 mM NaCl for most of the accessions, while a level of 600 mM NaCl suited the production of seed oil.  相似文献   

3.
Sorghum, Sorghum bicolor (L.) Moench is an important food security crop widely grown by smallholder farmers in sub-Saharan Africa (SSA), including Ethiopia. In SSA, the potential of sorghum production and productivity has not been realised due to an array of constraints. Colletotrichum sublineolum disease is one of the main biotic constraints causing significant yield losses. The objectives of this study were to assess farmers’ perception, preferences and constraints to sorghum production and productivity in western Ethiopia, and to identify key drivers for anthracnose resistance breeding. A participatory rural appraisal study was undertaken in six selected districts in the East Wellega and West Shewa Administrative Zones in Ethiopia. Data were collected through structured questionnaires involving 165 respondent farmers. Further focus group discussions were held with 180 farmers and development agents. Sorghum is the third most preferred cereal crop after Eragrostis tef and Zea mays in western Ethiopia. About 79% of interviewed farmers cultivated sorghum during the study season. Farmers perceived that sorghum production is constrained by anthracnose disease, bird attack, loose smut and covered smut diseases. The most important farmer-preferred traits in sorghum varieties in the study areas were anthracnose resistance and tolerance to bird attack. Breeding sorghum varieties with the farmer-preferred traits is an important consideration to enhance productivity and adoption of improved sorghum cultivars in western Ethiopia.  相似文献   

4.
植物诱发突变技术育种研究现状与发展前景   总被引:5,自引:2,他引:3  
自1928年以来,诱发突变技术应用于农作物新材料创制和优良新品种培育已经在解决世界粮食安全与营养供给中发挥显著作用。据不完全统计,截至2009年9月,世界上60多个国家在170多种植物上利用诱发突变技术育成和推广了3088个突变品种,其中中国在45种植物上育成了802个突变品种,占目前国际诱变育成品种数据库中总数的四分之一而位居世界第一。中国育成的突变品种年最大种植面积900万hm2,每年为国家增产粮、棉、油10~15亿kg,社会经济效益超过20亿元。近年来,加速器离子束辐照、空间环境诱变等新型诱变手段,以及传统核辐射诱变技术的有效利用等在我国农作物诱变改良与新基因挖掘中的应用日趋活跃。植物基因组学和高通量DNA技术(如TILLING等)的发展将把传统诱变育种推向分子突变育种新时代,并将在支撑我国及世界粮食安全领域发挥更大作用。  相似文献   

5.
Enset, Ensete ventricosum, is a crop that contributes to food security for more than 20 % of Ethiopia’s population. One clone never fulfills all the ecological and social requirements and hence farmers maintain a diverse range of enset cultivars on their farm. The objective of this work was to assess morphological and use value related characterization and document the indigenous knowledge of farmers on classification, cultivation and utilization of enset. A total of 280 farm households in seven zones were surveyed using individual household interviews. The observed traits showed low to high levels of variability among enset clones with a Shannon–Weaver diversity index (H′) value of 0.154–0.827 for bulla (extracted starch) quality and midrib color, respectively. Moreover, the overall H′ mean of 0.399 confirmed the existence of low to medium levels of phenotypic variation. The mean squares due to genotypes were highly significant (P ≤ 0.01) for all the quantitative traits studied, suggesting the presence of substantial genetic variability among the 165 enset clones. Kocho (fermented starch) yield had significant positive correlation with bulla quality and plant vigor. Knowledge of farmers’ practices is currently used to validate agronomic innovations and inform the setting up of a network of phenotype collections managed by farmers.  相似文献   

6.
Cassava (Manihot esculenta Crantz) is an important food security crop or resource for poor rural communities particularly in Africa. The crop’s ability to produce high yields even under poor conditions and storability of its roots underground for longer periods or until needed makes it a model ‘food security crop’. In Benin Republic, cassava has been recognized as one of the major crop contributing towards dynamic value chains generating incomes for small-holder farmers. The crop is grown all over the country, however, the increased production are mainly recorded from far south and central parts of the country. Genetic improvement of cassava in Benin Republic is limited because of poor knowledge of genetic diversity present within the country. The main objective of this study was to assess the genetic diversity and relationships among elite cassava varieties collected from different regions of Benin using fluorescently labelled simple sequence repeat (SSR) markers and to compare the results with farmer’s knowledge and morphological traits. A total of 96 cultivars collected from major cassava growing areas such as Southern and Central Benin were classified into 24 different groups using farmers’ knowledge, while classification based on 18 morphological traits resulted in five groups. In total, sixteen SSR markers were tested for molecular analysis of the ninety-six cassava varieties. Among the sixteen, twelve SSR markers gave good banding pattern and were used to genotype the varieties. An average of 3.58 and 0.47 for number of alleles and polymorphism information content respectively was observed. The observed heterozygosity (Ho) ranged from 0.23 to 1.0 with an average of 0.66 indicating moderate level of diversity among the cultivars. Based on the proportion of shared alleles and hierarchical clustering, the 96 elite cassava varieties were classified as 74 unique varieties. Principal component analysis and analysis of molecular variance revealed no significant variation between the regions thus, explaining regular exchange of planting materials among cassava farmers across various regions. The moderate level of genetic diversity in famer’s field, revealed in the present study, is a good indication of the need for broadening the genetic base of cassava in Benin Republic and establishing a formal breeding program in the country.  相似文献   

7.
Sulfur (S) is one of the severely limited nutrients in rainfed semi‐arid tropical Alfisols. Its application plays an important role in improving the yield and quality of oilseed crops. To identify the optimum level of sulfur for greater yield and oil content in the sunflower crop (MSFH‐8) through suitable sources, a field experiment involving varying levels of S through two sources (gypsum and elemental S) in combination with standard levels of nitrogen (N) and phosphorus (P) was conducted on a sandy loam soil (Typic Haplustalf) at Hayathnagar Research Farm of Central Research Institute for Dryland Agriculture, Hyderabad, situated at an altitude of 515 m above mean sea level and on 78° 36′ E longitude and 17° 18′ N latitude. The response to S application in sunflower crop in terms of growth parameters, yield components, nutrient uptake, and seed oil content was conspicuous. The application of graded levels of sulfur at rates of 20, 40, and 60 kg ha?1 applied through elemental S significantly increased the seed yield of the sunflower crop over the control by 5.4, 10.7, and 18.1% respectively, whereas the corresponding increases in case of gypsum (CaSO4·2H2O) were 25.1, 28.8, and 33.9% respectively. The greatest seed yield of sunflower (1175 kg ha?1) and percentage oil content (39.7%) was obtained with 60 kg S ha?1 through gypsum under rainfed conditions. Our study clearly indicated that the application of S at relatively high levels significantly increased the uptake of N, P, and S. The percentage oil content in seed recorded a positive and highly significant relationship with the uptake of N (r = 0.958**), P (r = 0.967**), and S (r = 0.951**), signifying the importance of balanced nutrition in influencing the oil content of seed in sunflower. The application of S through gypsum at rate of 60 kg S ha?1 along with 40 kg N and 30 kg P2O5 ha?1 was most superior in enhancing the seed yield and percentage oil content in seed.  相似文献   

8.
Twelve pumpkin cultivars (Cucurbita maxima D.), cultivated in Iowa, were studied for their seed oil content, fatty acid composition, and tocopherol content. Oil content ranged from 10.9 to 30.9%. Total unsaturated fatty acid content ranged from 73.1 to 80.5%. The predominant fatty acids present were linoleic, oleic, palmitic, and stearic. Significant differences were observed among the cultivars for stearic, oleic, linoleic, and gadoleic acid content of oil. Low linolenic acid levels were observed (<1%). The tocopherol content of the oils ranged from 27.1 to 75.1 microg/g of oil for alpha-tocopherol, from 74.9 to 492.8 microg/g for gamma-tocopherol, and from 35.3 to 1109.7 microg/g for delta-tocopherol. The study showed potential for pumpkin seed oil from all 12 cultivars to have high oxidative stability that would be suitable for food and industrial applications, as well as high unsaturation and tocopherol content that could potentially improve the nutrition of human diets.  相似文献   

9.
大豆是重要的粮食和经济作物,是植物蛋白和植物油的主要来源,也是禽畜养殖业的主要饲料蛋白来源。我国作为世界第一大豆消费国,85%的大豆需要依赖进口,对国家粮食安全构成严重威胁。为探讨提升我国大豆产能的路径,振兴大豆产业,保障国家粮食安全提供参考,通过查阅文献与生产实际相结合的方法,针对我国大豆单产水平低、总产量不足,种植面积小、提升空间有限,大豆生产成本高、效益低,种植补贴政策不完善等影响大豆产业发展的问题,提出促进我国大豆产能提升的途径:从产量突破性品种培育、栽培技术改进和高产竞赛方面依靠科技进步提高大豆单产;从东北地区大豆面积恢复、西北地区大豆种植、盐碱地开发利用、大豆玉米带状复合种植推广等方面多渠道扩大大豆种植面积;完善大豆补贴及保险政策;从产教融合上提升人才培养质量,振兴大豆产业。  相似文献   

10.
Experiments were conducted on mustard (Brassica campestris cv.B9) in an old alluvial soil zone of Crop Research and Seed Multiplication Farm, Burdwan University, Burdwan, West Bengal, India, during the winter seasons of 2011–2012 and 2012–2013. The aim was to evaluate the use of vermicompost prepared from municipality waste and Eichhornia mixture and its efficacy on crop growth and yield. Different combined doses of vermicompost, dried cow dung and chemical fertilizer along with Azotobacter and phosphate-solubilizing bacteria compared to full recommended dose of chemical NPK fertilizer (100:50:50) were used to develop an alternative farming technology for sustainable crop production and conservation of natural resources. The variety B9 gave a significantly higher seed yield and oil content along with other growth and yield-contributing factors as well as being the most economically viable option against treatment T4 (i.e. 75% NPK + vermicompost at 2.5 tons per hectare) among all the treatments applied for the experiment and was found to be superior to other treatments in old alluvial soil of Burdwan, India. In both the experimental years, seed yield and oil content were found to be the best for the treatment T4 and was better than using chemical fertilizer.  相似文献   

11.
Sweetpotato (Ipomoea batatas L. (Lam)) is a nutritious food security crop for most tropical households, but its utilisation is very low in Ghana compared to the other root and tuber crops due to lack of end-user-preferred cultivars. Knowledge on the genetic control of important traits such as dry matter, starch and sugar content of sweetpotato storage roots in a breeding population is critical for making breeding progress in developing sweetpotato varieties preferred by farmers and consumers. This study used diallel mating design to elucidate general combining ability and specific combining ability, to determine the gene action controlling storage root dry matter, starch and sugar content in sweetpotato and the heterotic potential of the traits to facilitate the crop’s improvement for increased utilisation. A general model for estimating genetic effects, GEAN II, was used to analyse the data. Genetic variability was seen for dry matter, starch and sugar content of sweetpotato and much of this genetic variation was additive in nature. The study also revealed significant heterosis in sweetpotato which offers opportunity for breeding non-sweet, high dry matter sweetpotato varieties that are preferred by farmers and consumers in Ghana.  相似文献   

12.
The seed oils from fifteen hybrid Hibiscus varieties were analyzed for desmethyl sterol content to identify bioactive compounds that could promote the use of these oils for edible applications. Hibiscusis being developed as a new crop with edible and nutraceutical applications for the component tissues and tissue extracts. Previously, hybrid varieties were developed for ornamental purposes on the basis of flower morphology and color. Currently, the effects of selective breeding on seed oil components are of interest as these represent potential natural products with bioactive properties. In the present study, sterol structures were identified as the corresponding trimethyl silyl ether derivatives obtained from the unsaponifiable fraction of the seed oils. This material contained an average of 32 wt % sterols and exhibited a relative composition of sitosterol, 76.3%; campesterol, 10.3%; stigmasterol, 7.3%; 5-avenasterol, 4.4%; and cholesterol, 0.6%. The content of 5-avenasterol showed statistically significant variation among the hybrid varieties with a range of 1.2-5.8%.  相似文献   

13.
Vernonia galamensis is a new potential industrial crop with very high content of vernolic acid in the seed oil. The species is known to naturally grow as a weed in fields or in woodlands under a wide range of agroecological conditions of Africa. In order to study the existing variability in Ethiopia, germplasm collection was carried out. Vernonia grows wild in various ecosystems. Ten regions were explored from North, South, East, Southeast, Southwest and Central Ethiopia. A diverse range of habitats having different altitudes and ecological conditions was explored. Altitude of collecting sites varied between 1250 and 2050 m, and soil pH from 5.1 to 8.5. The most common soil type was sandy loam, and the organic matter content varied from 0.2% to 12.9%. At 80 sites, about 480 accessions were collected including different maturity time, plant type, flower color, and branching patterns as well as fatty acid composition. The mean vernolic acid content of the seed oil of the accessions was 74%, and ranged from 34% to 87%. A wide variability in composition of other fatty acids was observed. It was not possible to find Vernonia in some locations that were earlier indicated by herbarium specimens collected since 1840. This could be a sign of change in land use system and environmental degradation and, hence, loss of genetic resources of the species.  相似文献   

14.
African locust bean is an important non-timber leguminous tree species for food security in Sahelian zones of Africa. Despite its multipurpose uses by local inhabitants, not much is known about its nutritional importance and ethnobotany in Ghana. For this, one thousand farmers randomly selected from five towns in the transitional zone of Ghana were surveyed using participatory rapid appraisal tools and techniques. The major uses of the plant in the survey area include food, medicine and firewood. Men are involved in the collection of the fruits and women process the seed into “dawadawa”, a protein rich condiment. Folk names of the plant in the study area means a mother or helper indicating the importance of the plant in nutrition and food security. The leaf, bark, root and fruit of the plant are used to treat various medical problems including fever, diarrhoea, stomach problems, boils and burns. Bad odour, limited market access, lack of elite genotypes, bush fires and tedious labour operations were the main constraints of African locust bean production in Ghana. Results on the stages of domestication show that African locust bean is in early stages of domestication which suggest that the respondents are aware of the food value and have a sense of ownership of the crop. Proximate composition of the pulp and the dehulled seed was determined using the official method of the Association of Official Analytical Chemists revealed that the pulp contains 2.47 % ash, 2.15 % protein, 1.33 % fat, 6.9 % fibre and 74 % carbohydrates. The dehulled bean contains 3.91 % ash, 20.93 % protein, 26.33 % fat, 4.92 % fibre and 34.18 % carbohydrates. These findings justified urgent need to domesticate, conserve natural populations and to develop improved varieties to ensure food and nutrition security and health in Africa.  相似文献   

15.
An idea is advanced for the composition of seed base collections. Policy planning needs to be rethought as to the inventory of base collections. Curators often concentrate on the storage of unadapted cultivated materials while neglecting select improved cultivars and crop wild relatives. The fact that germ plasm customized to the farmer's immediate needs is present in low numbers in cold chambers suggests that base collection management operates at a relative distance from a market economy intent on food production. This attitude is antithetic to food security and raises the need for expert questioning on proper gene bank management. The view put forwarded here is that three major areas should head the inventory of base collections in genebanks, viz. landraces, improved breeding materials of multiple categories, and crop wild relatives. Base collections must ultimately serve society by becoming repositories for regulating and replenishing agricultural stocks, should stochastic catastrophe strike in the farm. The relentless pace of environmental degradation means that conservation per se is the top priority for crop wild relatives.  相似文献   

16.
油菜种子油酸含量的遗传改良   总被引:3,自引:1,他引:2  
杜海  郎春秀  王伏林  陈锦清  吴关庭 《核农学报》2011,25(6):1179-1183,1220
油菜是我国重要油料作物,菜籽油是我国城乡居民消费的主要食用油之一。菜籽油中的油酸营养价值很高,同时油酸也是一种重要工业原料。本文从国内外高油酸油菜育种现状、油菜籽油酸含量的诱变改良、遗传调控以及分子标记鉴定和QTL定位等几个方面介绍了油菜种子油酸含量遗传改良研究进展,旨在为今后进一步开展油菜高油酸育种研究提供参考。  相似文献   

17.
This paper reports the first ever investigation of the chemical components/composition of the seeds of Amaranthus pumilus (a threatened amaranth species) and compares the results to those of the more commonly cultivated Amaranthus hypochondriacus (Plainsman). This study clearly revealed that much genetic diversity exists between these species, indicating that potential breeding possibilities for the improvement of more commonly cultivated amaranth lines do exist. A. pumilus offers a much larger and more desirable seed size and weight (2-3-fold higher), permitting greater biomass production, in addition to lower levels (half) of free carbohydrate for improved value/performance in diabetic-type diets. In addition to the higher edible oil content found in A. pumilus, its lower saturated/unsaturated ratio (one of the lowest thus far measured) makes it potentially a better source of nutritional oil. In addition to the 2-fold-higher quantity of vitamin E found in A. pumilus, the higher levels of squalene also found may one day serve as a renewable crop source of this compound and may diminish the world's dependence upon marine animals. Considering the imminent danger posed to the survival of the seabeach amaranth in its native environment, it is hoped this study will raise public awareness of the importance of this species and thereby protect it from reaching extinction.  相似文献   

18.
The amphidiploid species Brassica carinata A. Braun is believed to have originated in the plateaus of Ethiopia and has been cultivated there as an oilseed crop since antiquity. The species possesses agronomically important genes of rare occurrence. Although there is a large number of collections in Ethiopia, information on the extent of their genetic diversity is very limited. Thirty-six accessions of ecologically diverse regions were tested at three locations and multivariate analyses on 13 morphological and seed characters were performed. There was generally a large amount of divergence in all characters. Geographic isolation of genes, however, was not observed. Both principal component and cluster analyses disclosed complex relationships among the accessions and characters. Accessions with potential genes of interest to improve earliness, yield components and oil and protein contents have been identified. Length of growing period and yield components contributed most for divergence and clustering pattern. Oil, glucosinolate and protein contents also varied among the accessions but not so much between clusters. Increasing protein in high-glucosinolate genotypes reduced oil content and should be more efficient in genotypes of low-glucosinolate genetic background.  相似文献   

19.
Crude vegetable oils are usually oxidatively more stable than the corresponding refined oils. Tocopherols, phospholipids (PL), phytosterols, and phenols are the most important natural antioxidants in crude oils. Processing of vegetable oils, moreover, could induce the formation of antioxidants. Black cumin (Nigella sativa L.), coriander (Coriandrum sativum L.), and niger (Guizotia abyssinica Cass.) crude seed oils were extracted with n-hexane and the oils were further fractionated into neutral lipids (NL), glycolipids (GL), and PL. Crude oils and their fractions were investigated for their radical scavenging activity (RSA) toward the stable galvinoxyl radical by electron spin resonance (ESR) spectrometry and toward 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical by spectrophotometric method. Coriander seed oil and its fractions exhibited the strongest RSA compared to black cumin and niger seed oils. The data correlated well with the total content of polyunsaturated fatty acids, unsaponifiables, and PL, as well as the initial peroxide values of crude oils. In overall ranking, RSA of oil fractions showed similar patterns wherein the PL exhibited greater activity to scavenge both free radicals followed by GL and NL, respectively. The positive relationship observed between the RSA of crude oils and their color intensity suggests the Maillard reaction products may have contributed to the RSA of seed oils and their polar fractions. The results demonstrate the importance of minor components in crude seed oils on their oxidative stability, which will reflect on their food value and shelf life. As part of the effort to assess the potential of these seed oils, the information is also of importance in processing and utilizing the crude oils and their byproducts.  相似文献   

20.
Genetic Resources and Crop Evolution - Soybean is a high-nutritional crop that provides a sustainable source of dietary protein and edible oil for human consumption and animal diet. In this...  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号