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1.
Trygve Berg 《Euphytica》2009,166(3):423-430
Farmers’ seeds are most often lumped together in one broad category called ‘landraces’. But such a category covers variety
types that reflect different levels of farmer involvement. Those differences matters when we discuss such issues as genetic
erosion, on-farm conservation and seed related policies. The term landrace can be traced to the time when ‘modern’ varieties
of cereals were introduced to European farmers in the late nineteenth century. The farmers’ varieties of the time were called
‘landraces’ and understood as seeds adapted to local growing conditions through natural adaptation usually with no intentional
selection. But the term was quickly adopted as generic for all farmers’ varieties including those that are bred and maintained
by active seed selection on-farm. Such farmer-bred varieties are better termed ‘folk varieties’. The article discusses how
interaction of crop characteristics and developing technologies resulted in the evolution of crop varieties as either landraces
or folk varieties. It is argued that vulnerability to different agents of genetic erosion and feasibility of on-farm conservation
are clearly different for the two categories of farmers’ varieties. Likewise seed policies, particularly the issue of Farmers’
Rights would benefit from clarity of type of farmers’ varieties. 相似文献
2.
Farmers' seed management practices open up new base populations for pearl millet breeding in a semi-arid zone of India 总被引:2,自引:0,他引:2
K. Vom Brocke T. Presterl A. Christinck E. Weltzien R. H. H. Geiger 《Plant Breeding》2002,121(1):36-42
Farmers in western Rajasthan (north‐west India) produce and maintain their landrace populations of pearl millet through their own distinct seed management practices. The objective of this study was to characterize morphological and agronomic variability of different traits between and within three farmers' populations using quantitative‐genetic parameters. Populations examined were a typical landrace and two modified landraces, which were generated through farmer introgression of modern varieties with different levels of subsequent selection. From these three populations, 100 random full‐sib progenies were evaluated in field trials at two locations in western Rajasthan over two years. Significant genetic variation existed within the three populations. Estimates of heritability were moderate to high for all observed traits. Predicted selection response for grain yield across environments was 1.6% for the typical landrace and 2.2% for both the modified landraces. Results suggest that the introgression of modern varieties into landraces had increased the genetic diversity. Therefore, farmers' current breeding activities could open up new resources for plant breeding programmes aiming at plant improvement for the semiarid zones of India. 相似文献
3.
A. Teshome B.R. Baum L. Fahrig J.K. Torrance T.J. Arnason J.D. Lambert 《Euphytica》1997,97(3):255-263
Fourteen phenotypic characters were chosen for the purpose of obtaining taxonomic evidence on the resemblances of 177 accessions
of sorghum from North Shewa and South Welo regions of Ethiopia. Canonical Discriminant Analysis (CDA) and Modeclus cluster
analysis were conducted to see if the 177 accessions could form clusters based on their morphological characters, and to test
the consistency of farmers’ naming of the five most common Sorghum landraces represented by 44 accessions. Multivariate analyses
grouped the 177 accessions into three clusters linked by a few phenotypic intermediate landraces. A botanical key was established
for easy classification of the Sorghum crop plants grown in the study area. The number of accessions of the five most common
landraces named by the farmers formed dissimilar groups, suggesting that farmers’ naming of these Sorghum landraces are consistent.
Midrib color, grain color, grain size, glume color, glume hairiness, and grain shape were the leading morphological characters
used by the farmers in naming these Sorghum landraces.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
It is widely recognized that conventional plant breeding has been more beneficial to farmers in high-potential environments
or those who can profitably modify their environment to suit new cultivars, than to the poorest farmers who cannot afford
to modify their environment through the application of additional inputs and cannot risk the replacement of their traditional,
well known and reliable varieties. As a consequence, low yields, crop failures, malnutrition, famine, and eventually poverty
still affect a large proportion of humanity. Participatory plant breeding (PPB) is seen by several scientists as a way to
overcome the limitations of conventional breeding by offering farmers the possibility to choose, in their own environment,
which varieties suit better their needs and conditions. PPB exploits the potential gains of breeding for specific adaptation
through decentralized selection, defined as selection in the target environment, and is the ultimate conceptual consequence
of a positive interpretation of genotype × environment interactions. The paper describes a model of PPB developed by The International
Center for Agricultural Research in the Dry Areas and used successfully in several countries in West Asia and North Africa.
Genetic variability is generated by breeders, selection is conducted jointly by breeders, farmers, and extension specialists
in a number of target environments, and the best selections are used in further cycles of recombination and selection. Technically,
the process is similar to conventional breeding, with three main differences. Testing and selection take place on-farm rather
than on-station, key decisions are taken jointly by farmers and the breeder, and the process can be independently implemented
at a large number of locations. The model also incorporates seed production. Farmers handle the initial phases, multiplying
promising breeding material in village-based seed production systems. The PPB model is flexible; it can generate populations,
pure lines, and eventually mixtures of pure lines in self-pollinated crops; as well as hybrids, populations, and synthetics
in cross-pollinated crops. PPB has several advantages. New varieties reach the release phase much faster than in conventional
breeding, and are better suited to farmers’ needs and willingness to invest in inputs and management. Release and seed multiplication
activities concentrate on varieties known to be farmer-acceptable. These advantages are particularly relevant to developing
countries where large investments in plant breeding have not yielded returns, and many “improved” varieties developed through
conventional breeding are not adopted by farmers. PPB also ensures that biodiversity is maintained or increased because different
varieties are selected at different locations. In addition to the economical benefits, participatory research has a number
of psychological, moral, and ethical benefits, which are the consequence of a progressive empowerment of the farmers’ communities;
these benefits affect sectors of their life beyond the agricultural aspects. In conclusion, PPB, as a case of demand driven
research, gives voice to farmers, including those who have been traditionally the most marginalized such as the women, and
elevates local knowledge to the role of science. 相似文献
5.
Participatory plant breeding (PPB) methods were used to develop two farmer-accepted, cold-tolerant rice varieties in Nepal
— Machhapuchhre-3 (M-3) and Machhapuchhre-9 (M-9). Both were derived from the cross Fuji 102/Chhomrong Dhan. Following the
introduction of these varieties, the changes in the rice landraces and varieties that farmers grew were studied in ten villages.
In seven of them for which data were analysed for both 1996 and 1999, adopting farmers grew 18 landraces and four modern varieties
of which three, M-3, M-9 and Lumle-2, were the products of PPB. These three varieties covered 10% of the total rice area and
33% of the rice area of the adopting farmers in the seven study villages in the 1999 survey. The adoption of the PPB varieties
impacted most on the more commonly grown landraces. With the exception of two villages, the varietal richness among adopting
farmers was either static or increased, and there was an overall increase in allelic diversity. However, in future, the
increasing adoption of M-3 and M-9 could result in significant reductions in varietal richness, although, allelic diversity
may not be greatly reduced.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
6.
An on-station experiment was carried out in northern Namibia to compare local landraces of watermelon to modern varieties.
Three groups of local watermelon are distinguished by farmers in Namibia: watermelons for fresh consumption, cooking melons
used for porridge, and seed melons for oil pressing. The present study was carried out to estimate agronomic potential of
the local landraces and verify whether agronomic characteristics would justify the local groupings. Important agronomic and
fruit-quality traits (yield, earliness, fruit weight, fruit number, rind thickness, soluble solids, seed weight, and tolerance
to biotic and abiotic stress) were measured in seven landraces (three watermelons, three cooking melons and one seed melon)and
compared to three modern cultivars frequently grown in Namibia. The study revealed that well-adapted, productive Citrullus lanatuslandraces are available, and cultivated by local farmers throughout the northern regions of Namibia. Based on a combination
of agronomic characteristics these local varieties could be grouped into three distinct types: watermelons, cooking melons,
and seed melons, in agreement with farmers classification. Landrace water melons were characterized by smaller, less sweet
fruits with larger seed and a thicker rind compared to modern varieties. Yield level was comparable but development was later
and fruit number in some cases higher. Cooking water melons were less sweet than local water melon with large fruits comparable
in size to modern cultivars. The only included seed watermelon had small fruits with large seeds and low soluble sugars. Yield
varied from 118 t/ha for a giant cooking melon, out yielding all other accessions, to only 10t/ha for the seed melon type,
but with considerable variation within groups. The earliness of commercial varieties maybe of interest in developing a mixed
portfolio of short- and long-cycle landraces, whereas plant vigour, resistance and seed characters in some of the Namibian
landraces may be important traits for breeding for both local purposes and for commercial varieties.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
F. Mekbib 《Euphytica》2006,152(2):163-176
Sorghum (Sorghum bicolor (L.) Moench) is the fifth most important cereal crop worldwide and it is the fourth most important crop in Ethiopia. The national average yield amounts 1302 kg/ha. In order to assess the achievement in farmer breeding various types of research were undertaken. These include survey research to quantify the trend in productivity, the level of and reasons for adoption of improved varieties, yield performance and preference evaluation of farmers’ varieties (FVs) and improved varieties (IVs). As per the trend analysis over the last four decades, total production and yield per hectare has increased by 11.63 and 14.2%, respectively. However, area allocated to sorghum has decreased over years by −2.93%. The lack of consistent productivity is attributed to the fluctuation of environmental factors. Sorghum production in Ethiopia is predominantly based on varieties developed by farmers. The share of IVs is very low. FVs and IVs are adopted by 87.3 and 12.7% of the farmers, respectively. Besides, the adoption of IVs is limited to the lowland crop ecology. The comparative yield of FVs is higher than IVs by 132%. On top of yield, farmers do prefer their varieties for other multipurpose values namely feed, fuel wood and construction material. FVs under production are identified in each wereda. Farmer breeding has been successful compared to four decades of formal breeding. On the other hand, both farmer and formal breeding are not without weaknesses; a comparative balance sheet is outlined for both. Ideotypes for the three major crop ecologies are suggested and integrated plant breeding is anticipated to develop the proposed ideotypes thereby increase sorghum productivity in the region. 相似文献
8.
P. E. Abidin F. A. van Eeuwijk P. Stam P. C. Struik M. Malosetti R. O. M. Mwanga B. Odongo M. Hermann E. E. Carey 《Plant Breeding》2005,124(5):491-497
Sixteen sweet potato varieties were evaluated for fresh storage root yield in 20 trials during 2000–2001 for three seasons in four locations in Uganda. Of the 16 varieties, 11 were developed by farmers and five by a central breeding programme. The behaviour of the varieties was quantified in terms of wide adaptation (genotypic mean across trials), specific adaptation (genotypic predictions for specific locations) and stability (Shukla stability variance). With respect to all three aspects of yield behaviour, farmer varieties performed on average better than the official varieties. The results illustrate the potential that farmer varieties can have in the improvement of sweet potato in Uganda and other regions where high diversity of sweet potato landraces exists. 相似文献
9.
Pearl millet (Pennisetum glaucum (L.) R. Br.) cultivars for marginal, arid environments need to combine the adaptation to stress conditions of indigenous landraces with an improved yield potential and disease resistance, to allow them to both perform well in farmers fields and to meet the requirements for cultivar release. This paper evaluates landrace-based topcross hybrids (adapted landraces crossed on high-yielding male-sterile lines), as a quick and efficient way of achieving this objective. Topcross hybrids showed a consistent increase in biomass production across all test environments, including the harsh arid zone environments. Depending upon the plant type of the male-sterile used to make the hybrid, this was expressed as increased grain yield only, or increased grain and fodder yields. The downy mildew (Sclerospora graminicola) reaction of the topcross hybrids was determined by the reaction of the male-sterile line used, with the resistant male-sterile producing resistant topcross hybrids and vice-versa. Topcrossing adapted landraces on high-yielding male-sterile lines thus provides an opportunity to improve disease resistance and grain and/or fodder yields, with no apparent loss of adaptation to the marginal environments in which the landraces have evolved.ICRISAT Journal Article no. 1575 相似文献
10.
Experimental results and farmer surveys from a Mexican community located in the buffer zone of a biosphere reserve indicate
that farmers' seed selection practices protect the phenological integrity of their traditional maize varieties as they define
them, despite numerous factors contributing to genetic instability. Analysis of morphological and genetic data suggests that
when subjected to significant gene flow through cross-pollination, ear characteristics are maintained through farmers' selection
even though other characteristics may continue to evolve. Because the effects of farmers' selection practices are confined
largely to ear characteristics, their practices appear to offer only limited scope for variety improvement. Farmers' expectations
of what they can achieve through seed selection are similarly limited. These findings suggest complementary roles for professional
breeders and Mexican farmers in enhancing mass selection methods to improve maize landraces on farms – if farmers themselves
perceive benefits from the collaboration.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
11.
Village seed systems and the biological diversity of millet crops in marginal environments of India 总被引:1,自引:0,他引:1
The study relates village seed systems to biological diversity of millet crops grown by farmers in the semi-arid lands of Andhra Pradesh and Karnataka, India. In these subsistence-oriented, semi-arid production systems the environment is marginal for crop growth and often there is no substitute for millet crops. Across communities, farmers grow 13 different combinations of pearl millet, sorghum, finger millet, little millet, and foxtail millet varieties, but individual farmers grow an average of only 2–3 millet varieties per season. The “village seed system” in this study refers to all channels through which farmers acquire genetic materials, separate from or in interaction with the commercial seed industry, observed at the local level. Data are compiled through household surveys and interviews with traders and dealers in village and district markets. Based on the concept of the seed lot, several seed system parameters are defined and measured by millet crop. Most seed transactions, including gifts of seed, appear to be monetized. Seed supply channels differ by improvement status of the genetic material. Regression results confirm that seed system parameters are statistically significant determinants of the spatial diversity of millet crops measured at the village level. Furthermore, both the trade through weekly village markets (shandies) and through the formal seed supply channel contribute positively to the breadth of genetic materials in these communities. Ways should be found to strengthen and improve the overall efficiency of the seed system, including both formal and informal channels, in order to reduce the costs to farmers of procuring and managing diverse crop varieties. 相似文献
12.
MA Yan-Ming FENG Zhi-Yu WANG Wei ZHANG Sheng-Jun GUO Ying NI Zhong-Fu LIU Jie 《作物学报》1962,46(12):1997-2007
Grain yield is one of the most important goals in wheat breeding, and agronomic or yield-related traits can directly reflect the characteristics of varieties. In order to determine the evolution of genetic diversity in agronomic traits of Xinjiang winter wheat varieties and their adaptabilities to different ecological environments, 134 winter wheat landraces and 54 moderns bred varieties from Xinjiang were selected for agronomic trait investigation. They were planted in three different ecological environments (Urumqi and Yining in Xinjiang province, and Tai’an in Shandong province) for two consecutive growth seasons, and nine agronomic and yield-related traits were surveyed and analyzed. The estimated broad sense heritability of nine agronomic and yield traits was in descending order: plant height > grain width > grain length/width ratio > spike length > spikelet number > thousand- kernel weight > grain number per spike > grain length > fertile spikelet number. Correlation analyses of nine agronomic and yield traits showed that these traits were correlated with each other. It was found that the plant height, spike length and grain length/width ratio of landraces were higher than that in modern bred varieties, but the grain number per spike, thousand kernel weight, grain length and grain width in landraces were less than that in modern bred varieties. However, the correlation coefficient of these nine traits was higher in modern bred varieties than that in landraces. These variations reflected the evolution of Xinjiang winter wheat varieties in agronomic traits in recent years. This study may provide important information for breeders to select the breeding parents in different winter wheat regions. 相似文献
13.
A. M. Osman C. J. M. Almekinders P. C. Struik E. T. Lammerts van Bueren 《Euphytica》2008,163(3):511-522
Main stream commercial onion breeders do not select varieties for organic farming, but solely for conventional farming. Seed
companies consider the organic market too small to justify investments in breeding for this sector. In order to study if their
varieties also suit organic farmers’ needs we interviewed four Dutch commercial onion breeders on their breeding programme
and selection criteria and compared the outcome with a variety profile composed of the priority traits of Dutch organic farmers.
Breeders gave priority to the same storage and bulb quality traits that are demanded by organic farmers, because organic onions
are exported to conventional supermarkets that apply the same quality standards to organic and conventional onions. However,
organic farmers also need varieties that perform well in the field. Breeders give low priority to field selection. Furthermore,
three of the four seed companies only breed hybrids. The cytoplasmic male sterility system used to produce these hybrids does
not comply with organic principles. We conclude that at present breeders can provide varieties that meet organic farmers’
demands for storability and quality traits, but they should give higher priority to field selection to also improve required
field traits. The latter will only occur, if in future the organic seed market will grow. If the organic sector wants varieties
developed according to its own principles, it should either set up its own onion breeding programme or seek alliances with
breeding companies that are prepared to harmonize their breeding methodology with the organic principles. 相似文献
14.
In the Andean region, the Preduza project and its partners combined breeding for durable disease resistance using locally
adapted cultivars and farmer participatory methods. The approach taken resembles participatory variety selection (PVS). Farmers
participated in the selection of advanced materials, rather than finished cultivars. This paper describes this approach and
reports experiences with farmers–breeders collaboration.
As breeders involved farmers as participants, they learned more about the most important criteria of male and female farmers
for preferred cultivars in the marginal environments of Andean cropping systems. This approach encouraged the use of locally
adapted cultivars (often landraces), made the breeders less dependent on foreign materials, and has resulted in selection
and development of new wheat, barley, common bean, quinoa, potato and maize cultivars.
Breeding programmes based on crossing locally adapted cultivars followed by selection by the breeders in the early phases
of the breeding programmes and by participatory selection with the farmers in the more advanced stages of the breeding programmes
appeared successful. It became clear that breeders must be well acquainted with the farmer preferences such as the requirements
for specific agronomic, storage, processing and marketing traits.
Over a period of five years the centralized formal breeding approach predominantly based on material produced by the international
institutes was replaced by decentralized breeding approaches based largely on local germplasm with extensive farmer participation. 相似文献
15.
16.
The Ethiopian peasant farms are characterized by highly varied micro-environments differing in characteristics such as topography,
soil type, water, temperature and fertility. The bulk of the durum wheat planting material currently in use on these farms
is largely represented by traditional farmers' varieties/landraces.
These traditional farmers' varieties/landraces generally, are stable but low yielding, and often fail to adequately meet the
level of productivity essential for production beyond subsistence level, unless they are enhanced to improve their competitiveness
with modern varieties in respect to yield. Improving the productivity of landraces, while maintaining an appreciable level
of genetic diversity is crucial to yield stability. This could be achieved by developing composites that are formed by bulking
together three or more potentially high yielding spikes (agrotypes) that vary for various morphologic and agronomic characteristics,
but due to their similarity in plant height, maturity, glume color and seed color give the composite a uniform field appearance
like a modern variety.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
17.
转型时期杂交水稻的困境与出路 总被引:8,自引:0,他引:8
杂交水稻技术是我国自主创新并领先于世界的重大技术, 杂交水稻技术在水稻生产中的成功应用为保障我国粮食安全做出了巨大贡献。由于杂交稻品种选育策略和种子生产与经营方式没有适应目前水稻生产的转型变化, 最近几年我国杂交稻的种植面积有下降的趋势。这并不是杂交稻技术本身的问题, 国内外的生产实践证明杂交稻仍然代表先进的水稻生产技术。如果我们尽快地调整杂交稻的育种目标, 培育出适合于轻简化和机械化水稻生产方式、综合抗性好、资源利用效率高、稻米品质优良的杂交稻组合, 通过轻简化和机械化栽培技术降低杂交稻的种子生产成本和种子价格, 我国的杂交稻有望迅速走出目前的困境。 相似文献
18.
Summary Pure line selection for grain yield applied within four durum wheat local landraces (Triticum turgidum L. var durum) was studied in an effort to determine: (i) the agronomic performance of selected line mixtures (bulks) and their value as
potential new cultivars, (ii) the effectiveness of pure line selection for grain yield within local landraces and (iii) the
correlated selection response of yield components and kernel quality traits. Four local durum wheat landraces were used. Two
of them, Mytilini-1 and Mytilini-2 are still cropped in some rural areas of the island Mytilini whereas the other two, Limnos
and Mavragani are maintained in the Greek Gene Bank. Following their preliminary evaluation for agronomic performance under
current growing conditions, 100 individual plants from each landrace were randomly selected. Selected plants (pure lines)
were field evaluated head to row during 1997–98 and 1998–99 growing seasons. Based on grain yield performance, bidirectional
selection, high vs low, was practised within each landrace. Thus the five higher yielding lines and their corresponding lower
ones from each landrace were identified. Selected lines, with no further progeny testing, were pooled using a balanced seed
composite to form the high yielding five line bulk and its respective low counterpart. The resulting 16 bulks (eight high
and eight low) along with their four source landraces and two commercial varieties, Mexicalli and Simmeto, used as checks,
entered field testing for agronomic performance in two and one location during 1999–00 and 2000–01 growing seasons respectively.
Data for grain yield and yield components (1000 kernel weight, number of kernels, and productive tillers) along with kernel
quality data (protein content and vitreous) were recorded. Data for grain yield indicated that the landraces studied seemed
to be line mixtures, as expected, since they responded to bidirectional phenotypic pure line selection. The high yielding
bulks were of interesting agronomic performance, equivalent to or significantly better than that of the commercial checks
and are worth further testing as potential cultivars. Selected high bulks of Mytilini 2 landrace significantly outyielded
both the source landrace and the commercial checks maintaining the high protein content of the source landrace, which was
significantly higher than checks. This performance provides evidence that the within landraces selection of lines combining
high grain yield with high protein content seems to be feasible. In conclusion, evidence is presented that genetic variability
seems to be available within the landraces studied which could be worth using in breeding programs. Furthermore the simple
pure line selection breeding effort undertaken seemed to be effective in developing line bulks with promising performance
and worth further testing as potential cultivars. 相似文献
19.
Elaine McElhinny Eduardo Peralta Nelson Mazón Daniel L. Danial Graham Thiele Pim Lindhout 《Euphytica》2007,153(3):373-384
Summary Field trials were carried out in Ecuador with two indigenous communities, Ninín Cachipata and La Esperanza, to determine farmers’
preferences for quinoa (Chenopodium quinoa Willd.) cultivars and to improve PPB processes. More women than men participated, reflecting that quinoa, a primarily subsistence
crop, is mainly managed by women. Farmers’ field selection criteria for quinoa in the field were mostly based on yield, earliness
and plant colour; however only breeders’ measurements of yield and panicle height significantly correlated to farmer selection
scores. Older women gave higher scores than younger women or men, apparently due to a concept of no cultivar being without
value. Working in same gender pairs improved evaluation richness. INIAP technicians were more discriminating in their evaluations
than farmers. They also used additional selection criteria of disease resistance and uniformity. At seed selection, farmers
from Ninín Cachipata, where food security is not assured, chose lines based on yield, while farmers from La Esperanza, where
resources are less limiting, also considered seed size, colour, saponin content and marketability. Field characteristics were
not taken into consideration at seed selection, signifying that farmers are less interested in those characteristics, or that
it was difficult for them to correlate field data when presented in tabular form with seed characteristics. Future trials
with small farmers should have fewer lines or replications to avoid farmer fatigue during evaluation. Farmers who grow primarily
for subsistence in semi-arid environments have more interest in growing quinoa, and more to gain from having improved cultivars;
therefore future participatory efforts should focus on them. 相似文献
20.
Kuljit Kaur Cheema Navtej S. Bains Gurjit S. Mangat Aparna Das Yogesh Vikal Darshan S. Brar Gurdev S. Khush Kuldeep Singh 《Euphytica》2008,160(3):401-409
Modern rice varieties that ushered in the green revolution brought about dramatic increase in rice production worldwide but
at the cost of genetic diversity at the farmers’ fields. The wild species germplasm can be used for broadening the genetic
base and improving productivity. Mining of alleles at productivity QTL from related wild species under simultaneous backcrossing
and evaluation, accompanied by molecular marker analysis has emerged as an effective plant breeding strategy for utilization
of wild species germplasm. In the present study, a limited backcross strategy was used to introgress QTL associated with yield
and yield components from Oryza rufipogon (acc. IRGC 105491) to cultivated rice, O. sativa cv IR64. A set of 12 BC2F6 progenies, selected from among more than 100 BC2F5 progenies were evaluated for yield and yield components. For plant height, days to 50% flowering and tillers/plant, the introgression
lines did not show any significant change compared to the recurrent parent IR64. For yield, 9 of the 12 introgression lines
showed significantly higher yield (19–38%) than the recurrent parent IR64. Four of these lines originating from a common lineage
showed higher yield due to increase in grain weight and another three also from a common lineage showed yield increase due
to increase in grain number per panicle. For analyzing the introgression at molecular level all the 12 lines were analyzed
for 259 polymorphic SSR markers. Of the total 259 SSR markers analyzed, only 18 (7.0%) showed introgression from O. rufipogon for chromosomes 1, 2, 3, 5, 6 and 11. Graphical genotypes have been prepared for each line and association between the introgression
regions and the traits that increased yield is reported. Based on marker trait association it appears that some of the QTL
are stable across the environments and genetic backgrounds and can be exploited universally. 相似文献