Dual origin of the cultivated rice based on molecular markers of newly collected annual and perennial strains of wild rice species, Oryza nivara and O. rufipogon

The direct ancestor of rice (Oryza sativa L.) is believed to be AA genome wild relatives of rice in Asia. However, the AA genome wild relatives involve both annual and perennial forms. The distribution of the retrotransposon p-SINE1-r2, a short interspersed nuclear element (SINE) at the waxy locus was analyzed in diverse accessions of the AA genome wild relatives of rice (O. rufipogon sensu lato). Most annual wild rice accessions had this retrotransposon, while most perennial types lacked this element, contradicting results to the previous studies. Results presented here suggest that O. sativa has dual origin that lead to indica-japonica differentiation. Results suggest the indica line of rice varieties evolved from the annual genepool of AA genome and the japonica varieties from the perennial genepool of AA genome wild rice.     

Diversity and differentiation of <Emphasis Type="Italic">Oryza sativa</Emphasis> and <Emphasis Type="Italic">O. rufipogon</Emphasis> in Indonesia

Analysis of the genetic structure of Indonesian Oryza sativa and O. rufipogon using neighbour-joining trees based on single nucleotide polymorphism (SNP) and simple sequence repeat (SSR) markers revealed that O. sativa in Indonesia is separated from O. rufipogon. Accessions of O. sativa in this study were differentiated into two major groups, indica and tropical japonica, excluding some varieties. SSR and SNP markers revealed the high value of differentiation (F _ST) and genetic distance (D) between indica and tropical japonica and we discovered four loci by SNP markers and one locus by SSR markers that play a role in differentiation between indica and tropical japonica. Interestingly, genetic diversity (H) in O. rufipogon was lower than that in O. sativa, however H in O. rufipogon was the highest and H in tropical japonica was the lowest when O. sativa was divided into two groups. Inbreeding coefficient (Fst) showed evidences that gene flow (Nm) between species and within species might be one of the mechanisms related to the diversification and differentiation of Indonesian rice germplasm by asymmetric pattern between species and within O. sativa as revealed by SSR and SNP markers. In addition, we found evidences on stabilizing selection in Indonesian rice germplasm and they might be the reasons why Indonesian rice germplasm did not differentiate due to source location of landrace. However, we found a weak relation between SSR and SNP markers probably due to highly polymorphic in SSR and the different properties of both markers.     

Cloning of genome-specific repetitive DNA sequences in wild rice (O. rufipogon Griff.), and the development of Ty3-gypsy retrotransposon-based SSAP marker for distinguishing rice (O. sativa L.) indica and japonica subspecies

In the rice genome, insertions and eliminations of transposable elements have generated numerous transposon insertion polymorphisms (TIPs). Common wild rice (O. rufipogon Griff.), the ancestor of Asian cultivated rice (O. sativa L.), carries abundant genetic variations. To find subspecies-specific (SS) markers that can distinguish O. sativa ssp. indica and ssp. japonica, some long terminal repeat (LTR) sequences (sc1-14) of AA genome-specific RIRE retrotransposon were isolated from O. rufipogon genome. Sequences sc1 and sc12 were successfully utilized to develop the SS marker system based on retrotransposon inserted position polymorphisms. Twenty-two SS markers (ssi1-9, ssj1-13) were developed, where ssi1-9 are the indica-specific types, and ssj1-13 the japonica-specific types. The average accuracy of these markers in distinguishing the two subspecies is over 85%. SS marker ssj-10 can distinguish the two subspecies at 100% accuracy. Principal component analysis (PCA) showed that these markers could successfully distinguish indica from japonica varieties, regardless of their geographical origin.     

Analysis of Genetic Diversity and Relationships in Waxy Rice (Oryza sativa L.) using AFLP and ISSR Markers

Opaque endosperm is the main phenotypic indicator for waxy rice, but other phenotypic and genotypic variation among waxy rice accessions has largely been ignored. Previous studies showed that wide diversity in starch physiochemical properties exists in both indica and japonica waxy rices, especially for starch gelatinization temperature (GT) which could be divided into a high- and a low-GT group. In the present study, amplified fragment length polymorphism (AFLP) and inter-simple sequence repeat (ISSR) molecular markers were employed to examine genetic diversity and relationships of 56 waxy rice accessions. A total of 358 AFLP fragments were amplified with five primer combinations, showing a high level of polymorphism (78.3%). A total of 190 ISSR bands were generated with a single primer and a primer pair, showing a very high level of polymorphism (92.2%). The genetic distance matrices obtained from the two sets of markers were significantly correlated (r = 0.731, P = 0.004). The dendrogram generated with combined AFLP and ISSR markers could clearly differentiate the indica and japonica groups. Newly released varieties and breeding lines within each subspecies tended to be clustered together, whereas landraces were more distantly placed in the dendrogram. Only one AFLP band was found specific to the indica type, while no specific bands were found for starch GT. The implications for the conservation and breeding of waxy rice are discussed.     

Genetic variation and evolution of the Pit blast resistance locus in rice

Resistance (R) gene Pit in rice, encodes a protein with nucleotide binding sites–leucine rich repeat domain, prevents infections by strains of Magnaporthe oryzae in a gene for gene manner. Here, we analyzed the open reading frame (ORF) of Pit in 26 varieties including Oryza sativa L. subsp. indica Kato (Aus), indica (IND), temperate japonica (TEJ), tropical japonica (TRJ), aromatic (ARO) subgroups of Oryza sativa, and nine accessions of wild rice relatives including O. nivara and O. rufipogon from different growing areas. Twenty-one nucleotide differences were found within the ORFs of 35 accessions. Translation of these ORFs revealed a total of 11 Pit variants, seven of which were novel. Furthermore, variant H1 was identified in O. sativa and O. nivara; H2 and H10 were identified in O. sativa and O. rufipogon. H3, H4, and H11 were only found in O. sativa. H11 was the common type of TEJ and ARO; H3 and H4 was the specific type of TRJ and IND, respectively. H5, H6, and H7 were specific haplotypes of O. nivara, while, H8 and H9 were specific haplotypes of O. rufipogon. These results suggest that Pit is an ancient gene that exists before formation of rice domestication subgroups.     

Ecogeographic and genetic diversity based on morphological characters of indigenous rice (Oryza sativa L.) in Yunnan, China

Yunnan is one of the largest centres of genetic ecological diversity and the richest area for elite germplasm of rice (O. sativa L.) resources in the world. Its indigenous rice average diversity index of six ecological groups are, in turn, javanica (1.2319) > aman (1.1738) > communis (1.1726) > nuda (1.1618) > aus (1.1371) > boro (0.9889), and there are great differences between indica (1.1454) and japonica (1.2081). The indigenous rice in Yunnan can be divided into 58 varieties, almost the total number found in China, and the cultivars account for 8.6% of the total cultivars in China. A great difference in ecological diversity index of rice resources between prefectures or counties in Yunnan province also exists, with the southwest part (Lincang, Xishuangbanna, Dehong, Simao) and southeast part (Wenshan) having been found to be the largest centre of genetic diversity, as their average genetic diversity index ranges from 1.2735 to 1.2036, especially. The average diversity index of the Cangyuan, Gengma, Zhenkang, Yongde, Yingjiang, Jinghong, Menghai, Shuangjiang, Ruili, Longchuan, Mojiang, Wenshan and Guangnan counties, in particular, have an average diversity index ranging from 0.8 to1.0. On the contrary, in Diqing, Dongchuan, Kunming, Lijiang, Qujing, Chuxiong, it is comparatively low, i.e., 0.7843–1.1075. Differences in the ecological diversity index of rice resources between rice regions are small, only 1.1322 to 1.2849.     

The original features of rice (Oryza sativa L.) genetic diversity and the importance of within-variety diversity in the highlands of Madagascar build a strong case for in situ conservation

In situ conservation of crop genetic resources is widely recommended but, as yet, no methods have been developed to rank the genetic entities to preserve and the social organisations to involve. The highlands of Madagascar have been identified as a key site for rice, Oryza sativa, genetic diversity. To define conservation strategies, we performed multidisciplinary analysis of rice genetic diversity and factors shaping its distribution in the target region. Along with the indica and japonica rice subspecies of O. sativa, we confirmed the presence of an atypical rice group with a preferential habitat of 1,250–1,750 m. Spatial distribution of genetic diversity was uneven. The most determining factor of this unevenness was the altitude authorising or not the presence of different rice cropping systems and the associated types of varieties. Village and individual farmer’s wealth also had a determining role on the amount of rice diversity they hosted. While molecular variance between villages in a given interval of altitude represented 16 % of the total variance, within-village variance represented more than 75 % of the total, and within-farm variance 70 % of within-village variance. This hierarchical distribution of molecular variance suggests that a small number of samples per scale (altitude interval, village and farm) could allow to capture most of the genetic diversity observed. However, within-variety diversity was also important making ex situ conservation strategies impractical and costly. Implications of the within-variety diversity are discussed in terms of adaptive advantages, evolutionary processes, and need for in situ conservation.     

Genetic diversity associated with conservation of endangered Dongxiang wild rice (<Emphasis Type="Italic">Oryza rufipogon</Emphasis>)

The wild progenitor species (Oryza rufipogon) of Asian cultivated rice (O. sativa L.) is located in Dongxiang county, China which is considered its the northernmost range worldwide. Nine ex situ and three in situ populations of the Dongxiang wild rice (DXWR) and four groups of modern cultivars were genotyped using 21 SSR markers for study of population structure, conservation efficiency and genetic relationship. We demonstrated that the ex situ conservation of the DXWR failed to maintain the genetic identity and reduced genetic diversity. Therefore, in situ conservation is absolutely necessary to maintain the genetic identity, diversity and heterozygosity. Also, in situ conservation is urgently needed because natural populations in DXWR have decreased from nine to three at present due to farming activity and urban expansion. In DXWR, the three surviving in situ populations had greater expected heterozygosity than any cultivated rice, and were genetically closer to japonica than either the male-sterile maintainer or restorer lines, or indica. Japonica has the lowest genetic diversity of cultivated rice. As a result, DXWR is a rich gene pool and is especially valuable for genetic improvement of japonica rice because these O. rufipogon accessions are most closely related to the japonica as compared to O. rufipogon collected anywhere else in the world.     

Exploring genetic diversity and disease response of cultivated rice accessions (<Emphasis Type="Italic">Oryza</Emphasis> spp.) against <Emphasis Type="Italic">Pyricularia oryzae</Emphasis> under rainfed upland conditions in Benin

The main goal of this study is to gain insight into the relationship between the genetic profile of cultivated rice (Oryza spp.) accessions and their resistance to rice blast. Therefore, the genetic and phenotypic variability of a set of 350 cultivated rice accessions originating from Africa (Benin, Mali and Nigeria, Ivory Coast etc.) was examined. Seventy-seven fluorescent amplified fragment polymorphism (AFLP) markers were used to gain insight into the genetic variation and to classify the germplasm collection. In addition, the rice germplasm was assessed for its resistance to blast disease caused by Pyricularia oryzae in upland field conditions. Huge differences in responses of rice accessions to P. oryzae were observed, ranging from highly susceptible to highly resistant. Twelve percent of all accessions were highly resistant to P. oryzae. Based on their AFLP marker profile these highly resistant accessions could be separated from the other accessions. Stepwise regression revealed that the best prediction of the blast resistance level was achieved with a maximum number of 13 AFLP markers. Marker CTA22 was the most important for accurate prediction of blast resistance, this marker was present in all highly resistant accessions. It can be concluded that AFLP markers are a valuable tool to screen rice accessions for their susceptibility towards blast disease and that, based on a subset of markers, it is possible to predict the resistance to rice blast.     

Wild melon diversity in India (Punjab State)

We present here the first comprehensive genetic characterization of wild melon accessions from northern India. The genetic diversity among 43 wild melon accessions collected from the six agro-ecological regions of the Punjab State of India was assessed by measuring variation at 16 Simple Sequence Repeat (SSR) loci, morphological traits of plant habit and fruit morphological traits, two yield-associated traits, root nematode resistance and biochemical composition (ascorbic acid, carotenoids, titrable acidity). Variation among accessions was observed in plant habit and fruit traits and wild melon germplasm with high acidity and elevated carotenoid content and possessing resistance to Meloidogyne incognita was identified in the collection. A high level of genetic variability in wild melon germplasm was suggested by SSR analysis. Comparative analysis using SSRs of the genetic variability between wild melons from the north and other melons from the south and east regions of India and also reference accessions of cultivated melon from Spain, Japan, Korea, Maldives, Iraq and Israel, showed regional differentiation among Indian melon accessions and that Indian germplasm was not closely related to melon accessions from other parts of the world. A highly drought tolerant accession belonging to var. agrestis Naud. was also identified.     

Domestication and association analysis of Hd1 in Chinese mini-core collections of rice

Hd1 is one of the major photoperiod genes with high degree of polymorphisms and contributes to rice (Oryza sativa L.) flowering in different light conditions. Ninety-two rice landraces and 111 accessions of common wild rice (O. rufipogon Griff.) from the mini-core collections in China were selected and sequenced to analyze the domestication process and association of Hd1 with rice flowering. Association analysis revealed that three insertions and two deletions in the coding region of Hd1 are highly correlated with flowering time in the short-day condition. Phylogenetic analysis suggested that the polymorphisms of Hd1 in wild rice are related to the distributions. Haplotype analysis indicated that Hd1 in most O. sativa L. ssp. indica Kato and O. sativa L. ssp. japonica Kato landraces evolved from different O. rufipogon groups containing functional Hd1 and that most aus varieties were domesticated from O. rufipogon containing the long-insertions Hd1, suggesting multiple origins of Hd1. Moreover, O. rufipogon which contained the long-insertions Hd1 could only be found in Southern China, implying that Southern China might be one of the domestication centers of O. sativa. This study provides much significant information to aid further understanding of the domestication process of Hd1.     

Biodiversity in Ethiopian linseed (<Emphasis Type="Italic">Linum usitatissimum</Emphasis> L.): molecular characterization of landraces and some wild species

Molecular characterization of germplasm is important for sustainable exploitation of crops. DNA diversity was measured using inter-retrotransposon-amplified-polymorphism and inter-simple-sequence-repeat markers in 203 Ethiopian landraces and reference varieties of linseed (flax, Linum usitatissimum) and wild Linum species. Molecular diversity was high (PIC, 0.16; GD, 0.19) compared to other reports from the species. Genotyping separated reference from landrace accessions, and clustered landrace accessions from different altitudes and geographical regions. Collections showed evidence for recent introduction of varieties in some regions. The phylogeny supported L. bienne Mill. as the progenitor of domesticated L. usitatissimum. Markers developed here will be useful for genetic mapping and selection of breeding lines. The results show the range of characters that can be exploited in breeding lines appropriate for smallholder and commercial farmers in Ethiopia, producing a sustainable, secure, high-value crop meeting agricultural, economic and cultural needs.     

不同基因型机插稻植株氮素积累运转特性

【目的】明确机械化育插秧条件下不同基因型水稻氮素吸收利用的特点,分析提高其氮素吸收利用的途径。【方法】以3个中籼中熟杂交稻、3个中籼迟熟杂交稻、4个粳稻共计10个品种为材料,采用随机区组大田试验设计,测定不同生育时期各器官干物重和氮素含量、产量等,研究了不同基因型机插稻植株氮素积累、分配和运转特性的差异及其原因。【结果】1)育插秧机械化条件下水稻植株氮素积累符合Logistic曲线增长规律。2)整个生育期机插稻植株含氮量呈下降趋势,粳稻植株的含氮量在生长中期(拔节期—抽穗期)高于杂交籼稻,而后逐渐降低,到成熟期极显著低于杂交籼稻,中籼中熟杂交稻因降低缓慢到成熟期植株含氮量最高。3)粳稻植株的终极氮素积累量最低,中籼中熟杂交稻和中籼迟熟杂交稻终极氮素积累量平均比粳稻高23.0%和33.1%。4)中籼中熟杂交稻抽穗期—成熟期氮素积累量最大,在氮素积累上具有后发优势,且穗部分配率、叶片与茎鞘氮素表观转运率、氮素籽粒生产效率和氮素转运效率均较高,说明育插秧机械化条件下,中籼中熟杂交稻品种的氮素在转运和利用上具有高效性。其中,F优498的终极氮素积累量高,且具有前期积累快,后期运转分配合理等优势。5)中籼迟熟杂交稻氮素积累出现最大增长速率较晚,平稳持续增长时间较长,终极积累量最大,但氮素积累对产量的贡献没有优势。6)粳稻中杂交粳稻69优8号相比其他粳稻品种,氮素积累量大且产量高,也具有氮素转运和利用的高效性。【结论】机插稻植株氮素积累转运特性受不同基因型的显著影响。本研究采用植株含氮量、终极氮素积累量、百千克籽粒吸氮量等反映机插稻氮素吸收转运特性的指标进行比较发现,在育插秧机械化条件下,中籼中熟杂交稻相比中籼迟熟杂交稻和粳稻氮素具有积累转运和利用高效性,其中F优498在氮素积累、分配并促进产量形成方面具有遗传上的优势。中籼迟熟杂交稻虽具有氮素积累量潜力,但氮素积累对水稻产量的贡献相对较低。机插粳稻氮素积累较低,但相比其他粳稻品种机插杂交粳稻69优8号具有氮素积累量大且产量高的潜力,较适合机插。     

Genetic structure and differentiation among grapevines (<Emphasis Type="Italic">Vitis vinifera</Emphasis>) accessions from Maghreb region

Three gene pools representative of Vitis vinifera L. subsp. vinifera (=subsp. sativa Beger) growing in the Maghreb regions (North Africa) from Tunisia (44), Algeria (31) and Morocco (18) and 16 wild grape accessions (Vitis vinifera L. subsp. sylvestris (Gmelin) Beger) from Tunisia were analysed for genetic diversity and differentiation at twenty nuclear microsatellites markers distributed throughout the 19 grape chromosomes. 203 alleles with a mean number of 10.15 alleles per locus were observed in a total of 109 accessions. Genetic diversities were high in all populations with values ranging from 0.6775 (Moroccan cultivars) to 0.7254 (Tunisian cultivars). F _st pairwise values between cultivated grapevine populations were low but found to be significantly different from zero. High F _st pairwise values were shown between wild and cultivated compartments. Two parent offspring relationships, two synonyms and two clones of the same cultivar were detected. The rate of gene flow caused by vegetative dissemination of cultivated grapevine plants was not sufficient to genetically homogenise the pools of cultivars grown in different regions. The Neighbour Joining cluster analysis showed a clear separation according to geographical origins for the cultivated grapevines gene pools and revealed a high dissimilarity between cultivated and wild grapevine. However, three cultivars (Plant d’Ouchtata 1, Plant de Tabarka 3 and Plant d’Ouchtata 3) are very close to wild accessions and may result from a hybridisation between cultivated and wild accessions. The high level of differentiation between cultivated and wild accessions indicates that the cultivated accessions do not derive directly from local wild populations but could mostly correspond to imported materials introduced from others regions during historical times or derived from crossing between them.     

Variation of floral traits in Thai rice germplasm (<Emphasis Type="Italic">Oryza sativa</Emphasis>)

Floral traits play an important role in mating systems in flowering plant species. In rice, variation in floral traits has been established in a wide range of germplasm, but the variability of floral traits in Thai rice remains uncharacterized. Sixty-seven rice varieties that are cultivated throughout the country and two accessions of common wild rice were evaluated for nine floral traits to assess the extent of variation, and the differentiation of floral traits among groups of rice (improved rice varieties, selected traditional varieties, local traditional varieties and wild rice). The range of variation of all traits examined in Thai rice varied within the extent of variation that has been reported in other rice germplasm. Most of the floral traits observed in Thai rice have mean values similar to other reports, except in stamen traits, percentage of stigma exertion and the length of spikelet, which exhibited higher mean values than other germplasm investigations. Since these floral traits have a large contribution on outcrossing potential, Thai rice might have a greater chance of natural outcrossing compared to other cultivated rice germplasm. There is no clear differentiation in floral traits among groups of cultivated rice, but there are obvious differences in most of the floral traits between cultivated rice varieties and common wild rice, illustrated in the transformation of rice floral structures during domestication. The results have implications for outcrossing and spontaneous gene flow as well as a potential use in the parental lines for hybrid rice seed production.     

Genetic diversity,population structure and differentiation of rice species from Niger and their potential for rice genetic resources conservation and enhancement

Rice genetic resources conservation and evaluation is crucial to ensure germplasm sources for further crop breeding. We conducted a wide collection of Oryza species in Niger and characterize its diversity with microsatellites (or simple sequence repeats, SSR). The aims of this research were to get a better understanding of the extent of genetic diversity, its structure and partition within rice eco-geographical zones of Niger. There were 264 accessions found in farmers’ and other fields: 173 O. sativa (Asia’s rice), 65 O. glaberrima (Africa’s rice), 25 O. barthii, and 1 O. longistaminata (weedy perennial rice), which were genotyped with 18 SSR. A total of 178 alleles were detected, with a mean of 9.89 alleles per locus. The polymorphism information content was 0.65 and heterozygosity was estimated as 0.14. Two main well-differentiate genotypic groups, which correspond to Asian and African rice species, were identified. The SSR set divided the Asia’s rice group (solely indica) into irrigated and floating rice, with rainfed lowland rice in between. The African rice species group was composed of O. glaberrima, O. longistaminata and O. barthii accessions, but without any clear genetic differentiation among them likely due admixtures within the samples of O. barthii. Five accessions that could be natural interspecific hybrids were too admixed for assigning them to any of the two well-differentiated groups. The partitioning of the overall diversity showed that maximum variation was within genotypic groups and subgroups or cropping ecologies, rather than between eco-geographical zones. The eco-geographical distribution of the diversity suggests germplasm exchange in Niger. Next-steps for conserving rice and crop wild relatives in Niger could be taken using the findings of this research.     

Population genetic structure of in situ wild Sorghum bicolor in its Ethiopian center of origin based on SSR markers

In situ population studies of wild relatives of crops are crucial for the conservation of plant genetic resources, especially in regions with high genetic diversity and a risk of local extinction. Ethiopia is the center of origin for sorghum, yet little is known about the genetic structure of extant wild populations. Using 9 Simple Sequence Repeat loci, we characterized 19 wild populations from five regions, 8 local cultivar populations from three regions, and 10 wild sorghum accessions from several African countries. To our knowledge, this is the most comprehensive study to date of in situ wild sorghum populations in Africa. Genetic diversity corrected for sample size was significantly greater in the wild populations in situ than in local cultivars or the accessions. Approximately 41 % of the genetic variation in the wild plants was partitioned among populations, indicating a high degree of differentiation and potential value for germplasm conservation, and the average number of migrants (N_m) per generation was 0.43. Cluster analyses showed that some wild populations were grouped by geographic region, whereas others were not, presumably due to long-distance seed movement. Four wild populations from disjunct regions formed a unique cluster with an Ethiopian accession of subsp. drummondii and probably represent a weedy race. STRUCTURE and other analyses detected evidence for crop-wild hybridization, consistent with previous molecular marker studies in Kenya, Mali, and Cameroon. In summary, in situ wild sorghum populations in Ethiopia harbor substantial genetic diversity and differentiation, despite their close proximity to conspecific cultivars in this crop/wild/weedy complex.     

Genetic diversity in sorghum [<Emphasis Type="Italic">Sorghum bicolor</Emphasis> (L.) Moench] germplasm from Southern Africa as revealed by microsatellite markers and agro-morphological traits

Cultivated sorghum [Sorghum bicolor (L.) Moench] is an important food security crop in the semi-arid regions of the world including Asia and Africa. Its genetic diversity is contained mostly in traditional varieties and modern cultivars used by farmers. In this study, agro-morphological traits and molecular markers were used to assess genetic diversity in 22 accessions of cultivated sorghum from five countries (Botswana, Namibia, Swaziland, Zambia and Zimbabwe) in the Southern African Development Community (SADC) region. The study revealed a significant variation among 22 accessions in both qualitative and quantitative morphological traits, indicating the accessions’ promising potential as breeding material. For molecular analysis, 11 microsatellite primer-pairs were used, and generated a total of 70 alleles across 20 accessions. Analysis of molecular variance revealed a high level of genetic variation; 67 % among the accessions and 10 % among the five countries. The patterns of genetic diversity and the relationships observed in this study should provide insights for genetic resource conservation and utilization of sorghum germplasm in the SADC region.     

The diversity and sustainable development of crop genetic resources in the Lancang River Valley

This paper reviews the status of crop genetic resources in Yunnan province of China from 1978 to 1999. Results are presented of same research in the field of the diversity of cultivated and wild crop. Yunnan is one of the centre of origin or genetic diversity of more than 200 cultivated and wild crops. There are over 500 cultivated plants which account for over 80% of the total in China and more than 650 species of wild crops. In addition, there are more than 440 species of main wild flowers. According to our recently researches there are abundant species, subspecies and varieties of crop genetic resources in Yunnan Province. The Lancang River Valley is the richest genetic diversity centre of rice, maize, wheat, barley, buckwheat, legumes, ramie, sugarcane, vegetable, tea, actinidia and so on. For example, there are 59 varieties (including all varieties of Oryza sativa L. in China) in 5933 accession of Yunnan indigenous rice. The Lancang River Valley is one of the centre for genetic diversity of rice resources and a rich region for elite and rare rice resources of Yunnan, too. In order to protect the highly endangered crop genetic resources in the Lancang River Valley, it is necessary and very important to set up a collection, conservation, utilization and research system, enhancing their protection and utilization, in situ- and ex situ-conservation, farm management and sustainable production.