Despite its theoretical prominence and sound principles, integrated pest management (IPM) continues to suffer from anemic adoption rates in developing countries. To shed light on the reasons, we surveyed the opinions of a large and diverse pool of IPM professionals and practitioners from 96 countries by using structured concept mapping. The first phase of this method elicited 413 open-ended responses on perceived obstacles to IPM. Analysis of responses revealed 51 unique statements on obstacles, the most frequent of which was "insufficient training and technical support to farmers." Cluster analyses, based on participant opinions, grouped these unique statements into six themes: research weaknesses, outreach weaknesses, IPM weaknesses, farmer weaknesses, pesticide industry interference, and weak adoption incentives. Subsequently, 163 participants rated the obstacles expressed in the 51 unique statements according to importance and remediation difficulty. Respondents from developing countries and high-income countries rated the obstacles differently. As a group, developing-country respondents rated "IPM requires collective action within a farming community" as their top obstacle to IPM adoption. Respondents from high-income countries prioritized instead the "shortage of well-qualified IPM experts and extensionists." Differential prioritization was also evident among developing-country regions, and when obstacle statements were grouped into themes. Results highlighted the need to improve the participation of stakeholders from developing countries in the IPM adoption debate, and also to situate the debate within specific regional contexts. sustainable agriculture | technology adoption | collective action dilemma
Quinoa (Chenopodium quinoaWilld.) is a staple food crop for millions of impoverished rural inhabitants of Andean South America where it has been cultivated for millennia. Interest in quinoa, due largely to its superior nutritional characteristics, is fuelling a growing export market and has led to an increased focus on genetic research and the development of quinoa breeding programmes throughout South America. The success of these breeding programmes will rely heavily on the development of core germplasm collections and germplasm conservation. We report the development of a set of fluorescence-tagged microsatellite molecular markers that can be used to characterize genetic diversity within quinoa germplasm and we use this set of 36 microsatellites markers to genetically characterize the diversity of 121 accessions ofC. quinoaheld in the USDA germplasm bank, 22 accessions from the CIP-FAO international nursery collection and eight accessions representing parents from genetic mapping populations. A total of 420 alleles were detected among the quinoa accessions with an average of 11 alleles detected per microsatellite locus. Genetic heterogeneity was observed in 32% of the quinoa accessions at a given locus and suggests that many of these accessions represent heterogeneous seed lots or landraces. Both unweighted pair-group method with arithmetic averages (UPGMA) and principle components analysis (PCA) analyses partitioned the quinoa accessions into two main clusters. The first major cluster consisted of accessions from the Andean highlands of Peru, Bolivia, Ecuador, Argentina and extreme northeastern Chile. The other main cluster contained accessions from both the lowlands of Chile and a set of USDA accessions with no known passport data, collected by Emigdio Ball贸n. Using the patterns of genetic diversity detected within theC. quinoaaccessions we discuss hypotheses regarding quinoa's centre of diversity, including highland and lowland ecotype clustering patterns, origin of lowland varieties, origin of domestication, and diversity levels in the USDA and CIP-FAO collections.
an ideal balance of all 20 essential amino acids (Ruas et al., 1999). Quinoa (Chenopodium quinoa Willd.) is a widely consumed foodQuinoa is especially important as a source of protein crop and a primary protein source for many of the indigenous inhabitants of the Andean region of South America. The objective of this for subsistence farmers on the Altiplano of Bolivia and study was to develop a collection of reproducible and highly informa- Peru (Wilson, 1988), an area that covers 255 000 km 2 at tive microsatellite markers for quinoa. A total of 1276 clones were an elevation of 3500 to 3850 m above sea level and is sequenced from three microsatellite-enriched (CA, ATT, ATG) ligenerally characterized as cold and arid. Quinoa is one braries. Four hundred fifty-seven (36%) of the clones contained of only a few crop plants adapted to the extreme condiunique microsatellites. The most common repeated motifs, other than tions that characterize much of this region (Cusack, CA, AAT, and ATG, were GA and CAA. Flanking primers were 1984; Risi and Galwey, 1984; Prado et al., 2000; Vacher, designed for 397 microsatellite loci and screened using a panel of 1998). Although increasing quinoa productivity is a pridiverse quinoa accessions and one accession of C. berlandieri Moq., a mary food-security issue in the Andean region, limited wild relative of quinoa. Two hundred eight (52%) of the microsatellite research on quinoa genetics and plant breeding has been markers were polymorphic among the quinoa accessions. An additional 25 of the microsatellite markers (6%) were polymorphic when conducted (see reviews by Fleming and Galwey, 1995; the C. berlandieri accession was included in the analysis. Only in rare Risi and Galwey, 1984). Fortunately, a new awareness instances (nine) did a microsatellite amplify in quinoa and not in C. of the importance of quinoa, as well as a growing health berlandieri. The number of observed alleles ranged from 2 to 13, with food export market for quinoa, has led to the establishan average of four alleles detected per locus. Heterozygosity values ment of several new quinoa breeding programs throughranged from 0.20 to 0.90 with a mean value of 0.57. Sixty-seven markers out the Andean region of South America. In addition (32%) were highly polymorphic (H 諉 0.70). These microsatellites to germplasm management, principal objectives of these markers are an ideal resource for use in managing quinoa germplasm,programs include enhancing grain yield, disease resistrait mapping and marker-assisted breeding strategies. The wide crosstance, drought tolerance, and modulating saponin conspecies transportability of these markers may extend their value to tent (Ochoa et al., 1999). These programs recognize that research involving other Chenopodium species.the development and use of molecular markers are critical to meeting these objectives (A. Gandarillas, personal communication).
Quinoa ( Chenopodium quinoa Willd.) is an important seed crop for human consumption in the Andean region of South America. It is the primary staple in areas too arid or saline for the major cereal crops. The objective of this project was to build the first genetic linkage map of quinoa. Selection of the mapping population was based on a preliminary genetic similarity analysis of four potential mapping parents. Breeding lines 'Ku-2' and '0654', a Chilean lowland type and a Peruvian Altiplano type, respectively, showed a low similarity coefficient of 0.31 and were selected to form an F(2) mapping population. The genetic map is based on 80 F(2) individuals from this population and consists of 230 amplified length polymorphism (AFLP), 19 simple-sequence repeat (SSR), and six randomly amplified polymorphic DNA markers. The map spans 1,020 cM and contains 35 linkage groups with an average marker density of 4.0 cM per marker. Clustering of AFLP markers was not observed. Additionally, we report the primer sequences and map locations for 19 SSR markers that will be valuable tools for future quinoa genome analysis. This map provides a key starting point for genetic dissection of agronomically important characteristics of quinoa, including seed saponin content, grain yield, maturity, and resistance to disease, frost, and drought. Current efforts are geared towards the generation of more than 200 mapped SSR markers and the development of several recombinant-inbred mapping populations.
Quinoa is a regionally important grain crop in the Andean region of South America. Recently quinoa has gained international attention for its high nutritional value and tolerances of extreme abiotic stresses. DNA markers and linkage maps are important tools for germplasm conservation and crop improvement programmes. Here we report the development of 216 new polymorphic SSR (simple sequence repeats) markers from libraries enriched for GA, CAA and AAT repeats, as well as 6 SSR markers developed from bacterial artificial chromosome-end sequences (BES-SSRs). Heterozygosity (H) values of the SSR markers ranges from 0.12 to 0.90, with an average value of 0.57. A linkage map was constructed for a newly developed recombinant inbred lines (RIL) population using these SSR markers. Additional markers, including amplified fragment length polymorphisms (AFLPs), two 11S seed storage protein loci, and the nucleolar organizing region (NOR), were also placed on the linkage map. The linkage map presented here is the first SSR-based map in quinoa and contains 275 markers, including 200 SSR. The map consists of 38 linkage groups (LGs) covering 913 cM. Segregation distortion was observed in the mapping population for several marker loci, indicating possible chromosomal regions associated with selection or gametophytic lethality. As this map is based primarily on simple and easily-transferable SSR markers, it will be particularly valuable for research in laboratories in Andean regions of South America.
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