La capacidad competitiva y su incidencia en la exportación de los pequeños y medianos productores de quinua del distrito de Puno

La presente investigación tuvo como objetivo establecer si las capacidades competitivas de los pequeños y medianos productores de quinua del distrito de Puno permiten estructurar un clúster de exportación de dicho producto. La selección de la muestra para la investigación fue en base a 68 representantes de los productores de quinua del distrito de Puno a quienes se les aplicó un cuestionario de medición de capacidades como productores individuales o como parte de una organización de productores. El instrumento de la entrevista fue elaborado en función de las capacidades diversas manifestadas por agroexportadores de quinua ubicados en Lima; es decir, los atributos necesarios para realizar todos los procesos a través de una cadena exportadora. Los resultados obtenidos permiten evidenciar que los productores individuales presentan limitaciones significativas para convertirse en exportadores e, incluso, como productores organizados, aunque en menor medida. Sin embargo, si la política de apoyo a la agricultura del gobierno nacional, regional y local fuese orientada a promover la asociatividad, a crear capacidades de planta y de gestión, se podría viabilizar que los productores organizados se conviertan en exportadores directos. De esta manera se validaron la hipótesis general y las tres hipótesis específicas y, a la vez, se identificaron líneas de acción tanto de los productores en la fase tecnológica, de proceso y de gestión, como a nivel de los servicios que brinda el sector público; las que en conjunto permitirían establecer un modelo competitivo de pequeños y medianos productores de quinua en la provincia de Puno del departamento del mismo nombre, organizados en base a una cadena de valor sostenible.Tesi

Painting the green canvas: how pigments produce flower colours

Flowering plants are characterized by the production of striking flower colours and these colours are primarily caused by the accumulation of pigments in cells of the floral organs. The extraordinary array of colours displayed in flowers relies on four main pigment groups: chlorophylls, carotenoids, flavonoids and betalains. With thousands of different compounds, flavonoids are the most diverse and widespread pigment group. They include coloured anthocyanins, aurones and chalcones, as well as many flavonoid compounds such as flavones and flavonols that are invisible to humans, but visible to most pollinators since they absorb ultraviolet light (UV). Flowers may exhibit homogenous colours produced by only one type of pigment or extremely complex colour patterns caused by the accumulation of several types of pigments in the same or in different floral organs. Here, we review the ecological biochemistry of pigments affecting flower colour. We also present data of flower colour variation and provide future research directions guided by the physiological functions of floral pigments

Phenotypic plasticity in light-induced flavonoids varies among tissues in Silene littorea (Caryophyllaceae)

Plants respond to environmental stimuli in a diversity of ways including the production of secondary metabolites. Biosynthesis of plant phenolics, including flavonoids, is frequently activated in response to a variety of abiotic and biotic stressors (e.g. extreme temperatures, high radiation, pathogens, etc.). This induced reaction is typically assumed to be a plastic response, but the components attributable to plasticity vs genetic variance in these components are poorly understood. Here, we investigate the variation in flavonoid production (anthocyanins and flavones) in petals and in photosynthetic tissues (calyces, leaves and stems) of Silene littorea. We performed a common garden experiment with maternal families from three populations in which plants were exposed to different light treatments (sun exposure and shade). The concentrations of anthocyanins in photosynthetic tissues increased when plants were exposed to sun, except for leaves that showed very low quantities of anthocyanins in both light treatments; yet flavones are produced constitutively in both sun and shade treatments. The synthesis of both anthocyanins and flavones is mostly plastic, with 25 to 43% of total phenotypic variance explained by light environment. We found significant environmental effects in anthocyanin biosynthesis in calyces and stems, and in flavone production in all photosynthetic tissues. Petals showed considerably less plasticity in anthocyanin production in contrast with the accumulation of these compounds in calyces and stems. Flavones exhibited less than half of the degree of phenotypic plasticity compared to anthocyanins in calyces and stems. Overall, these results provide new insights into the degree of tissue-specific plasticity and flavonoid-specific response. Variable plasticity between flavonoids types in petals and photosynthetic tissues may allow this annual plant to differentially respond to changing light environments, while maintaining constitutive petal color in response to pollinators

UV radiation increases flavonoid protection but decreases reproduction in \u3ci\u3eSilene littorea\u3c/i\u3e

Plants respond to changes in ultraviolet (UV) radiation both morphologically and physiologically. Among the variety of plant UV-responses, the synthesis of UV-absorbing flavonoids constitutes an effective non-enzymatic mechanism to mitigate photoinhibitory and photooxidative damage caused by UV stress, either reducing the penetration of incident UV radiation or acting as quenchers of reactive oxygen species (ROS). In this study, we designed a UV-exclusion experiment to investigate the effects of UV radiation in Silene littorea. We spectrophotometrically quantified concentrations of both anthocyanins and UV-absorbing phenolic compounds in petals, calyces, leaves and stems. Furthermore, we analyzed the UV effect on the photosynthetic activity in hours of maximum solar radiation and we tested the impact of UV radiation on male and female reproductive performance. We found that anthocyanin concentrations showed a significant decrease of about 20% with UV-exclusion in petals and stems, and a 30% decrease in calyces. The concentrations of UV-absorbing compounds under UV-exclusion decreased by approximately 25% in calyces and stems, and 12% in leaves. Photochemical efficiency of plants grown under UV decreased at maximum light stress, reaching an inhibition of 58% of photosynthetic activity, but their ability to recover after light-stress was not affected. In addition, exposure to UV radiation did not affect ovule production or seed set per flower, but decreased pollen production and total seed production per plant by 31% and 69%, respectively. Our results demonstrate that UV exposure produced opposing effects on the accumulation of plant phenolic compounds and reproduction. UV radiation increased the concentration of phenolic compounds, suggesting a photoprotective role of plant phenolics against UV light, yet overall reproduction was compromised

Whole Plastome Sequencing Within \u3ci\u3eSilene\u3c/i\u3e Section \u3ci\u3ePsammophilae\u3c/i\u3e Reveals Mainland Hybridization and Divergence With the Balearic Island Populations

Reconstructing the phylogenetic relationships within Caryophyllaceae tribe Sileneae has been obscured by hybridization and incomplete lineage sorting. Silene is the largest genus in the Caryophyllaceae, and unraveling its evolutionary history has been particularly challenging. In order to infer the phylogenetic relationships among the five species in Silene section Psammophilae, we have performed a genome skimming approach to acquire the complete plastid genome (cpDNA), nuclear ribosomal cistron (nrDNA), and partial mitochondrial genome (mtDNA). We have included 26 populations, representing the range of each species\u27 distribution. This section includes five morphologically similar species endemic to the Iberian Peninsula and Balearic Islands (Ibiza and Formentera), yet some of them occupy distinct edaphic habitats (e.g. maritime sands, calcareous sandstones). In addition to phylogeographic analyses, genetic structuring using the chloroplast data set was inferred with Discriminant Analysis of Principal Components (DAPC), analyses of molecular variance (AMOVA), and a partial Mantel test. Reference-guided assembly of 50 bp single-end and 250 bp paired-end Illumina reads produced the nearly complete cpDNA genome (154 kbp), partial mtDNA genome (from 81 to 114 kbp), and the nrDNA cistron (6.4 kbp). Selected variable regions of the cpDNA and mtDNA assemblies were confirmed by Sanger sequencing. Phylogenetic analyses of the mainland populations reveal incongruence among the three genomes. None of the three data sets produced relationships consistent with taxonomy or geography. In contrast, Silene cambessedesii, present in the Balearic Islands, is the only species that forms a strongly supported monophyletic clade in the cpDNA genome and is strongly differentiated with respect to the remaining taxa of the Iberian Peninsula. These results contrast with those obtained for mainland populations. Across the entire analysis, only one well-supported mainland clade of Silene littorea and Silene stockenii emerges from the southern region of the Iberian Peninsula. DAPC and AMOVA results suggest the absence of genetic structure among mainland populations of Silene section Psammophilae, whereas partial Mantel test discarded spatial correlation of genetic differentiation. The widespread incongruence between morphology-based taxonomic boundaries and phylogeography suggests a history of interspecific hybridization, in which only a substantial geographic barrier, like isolation by the Mediterranean Sea, was sufficient to create and maintain species boundaries in Silene section Psammophilae

Transcriptome and Biochemical Analysis of a Flower Color Polymorphism in Silene littorea (Caryophyllaceae)

Flower color polymorphisms are widely used as model traits from genetics to ecology, yet determining the biochemical and molecular basis can be challenging. Anthocyanin-based flower color variations can be caused by at least 12 structural and three regulatory genes in the anthocyanin biosynthetic pathway (ABP). We use mRNA-Seq to simultaneously sequence and estimate expression of these candidate genes in nine samples of Silene littorea representing three color morphs (dark pink, light pink, and white) across three developmental stages in hopes of identifying the cause of flower color variation. We identified 29 putative paralogs for the 15 candidate genes in the ABP. We assembled complete coding sequences for 16 structural loci and nine of ten regulatory loci. Among these 29 putative paralogs, we identified 622 SNPs, yet only nine synonymous SNPs in Ans had allele frequencies that differentiated pigmented petals (dark pink and light pink) from white petals. These Ans allele frequency differences were further investigated with an expanded sequencing survey of 38 individuals, yet no SNPs consistently differentiated the color morphs. We also found one locus, F3h1, with strong differential expression between pigmented and white samples (>42x). This may be caused by decreased expression of Myb1a in white petal buds. Myb1a in S. littorea is a regulatory locus closely related to Subgroup 7 Mybs known to regulate F3h and other loci in the first half of the ABP in model species. We then compare the mRNA-Seq results with petal biochemistry which revealed cyanidin as the primary anthocyanin and five flavonoid intermediates. Concentrations of three of the flavonoid intermediates were significantly lower in white petals than in pigmented petals (rutin, quercetin and isovitexin). The biochemistry results for rutin, quercetin, luteolin and apigenin are consistent with the transcriptome results suggesting a blockage at F3h, possibly caused by downregulation of Myb1a.España , Ministerio de Ciencia e Innovación BES-2010-031073España , Ministerio de Ciencia e Innovación CGL2009-08257España , Ministerio de Ciencia e Innovación CGL2012-3764

Major flower pigments originate different colour signals to pollinators

Flower colour is mainly due to the presence and type of pigments. Pollinator preferences impose selection on flower colour that ultimately acts on flower pigments. Knowing how pollinators perceive flowers with different pigments becomes crucial for a comprehensive understanding of plant-pollinator communication and flower colour evolution. Based on colour space models, we studied whether main groups of pollinators, specifically hymenopterans, dipterans, lepidopterans and birds, differentially perceive flower colours generated by major pigment groups. We obtain reflectance data and conspicuousness to pollinators of flowers containing one of the pigment groups more frequent in flowers: chlorophylls, carotenoids and flavonoids

Comportamiento de cuatro cultivares de Cucurbita maxima cv. zapallito frente al parasitismo del nematodo de las agallas Meloidogyne incognita

El nematodo de las agallas, Meloidogyne incognita, es causante de pérdidas productivas en los principales cultivos hortícolas que se realizan en el albardón costero santafesino. El objetivo de la investigación fue determinar la reacción de cuatro cultivares comerciales de zapallito redondo de tronco (Cucurbita maxima cv. zapallito) frente al parasitismo de M. incognita. Las experiencias se condujeron en macetas bajo invernadero y se evaluaron los cultivares Nacional, Premier, Sais superselección y Máximo. Los tratamientos consistieron en inocular plantas de cada cultivar con 100 juveniles de segundo estadio de M. incognita y de sus correspondientes testigos no inoculados. A los 45 días de la inoculación se determinó el número de agallas, índice de Agallas, número de masas de huevos, índice de Masas de Huevos, número de huevos y el factor e reproducción. Los cuatro cultivares estudiados demostraron ser susceptibles a M. incognitaThe root-knot nematode, Meloidogyne incognita, causes yield losses in many horticultural crops in the coastal área of Santa Fe province. The aim of this research was to determine the reaction of four commercial cultivars of summer squash (Cucurbita maxima cv. zapallito) when parasitized by M. incognita. The experiments were conducted in pots under greenhouse conditions and Nacional, Premier, Sais superselection and Máximo cultivars were evaluated. The treatments consisted of plants of each cultivar inoculated with 100 second-stage juveniles of M. incognita and its corresponding control. 45 days after inoculation the number of galls, Gall Index, number of egg masses, Eggs Mass Index, number of eggs and reproduction factor were determined. The four cultivars studied showed susceptibility to M. incognitaEEA RafaelaFil: del Valle, Eleodoro Eduardo. Universidad Nacional del Litoral. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe; ArgentinaFil: Guzmán, Alejandro. Universidad Nacional del Litoral. Facultad de Ciencias Agrarias; ArgentinaFil: Belavi, Ariel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rafaela. Agencia De Extensión Rural Monte Vera; ArgentinaFil: Soressi, Marcelo Carlos. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rafaela. Agencia De Extensión Rural Monte Vera; Argentin

Transcriptome and Biochemical Analysis of a Flower Color Polymorphism in Silene littorea (Caryophyllaceae)

Flower color polymorphisms are widely used as model traits from genetics to ecology, yet determining the biochemical and molecular basis can be challenging. Anthocyanin-based flower color variations can be caused by at least 12 structural and three regulatory genes in the anthocyanin biosynthetic pathway (ABP). We use mRNA-Seq to simultaneously sequence and estimate expression of these candidate genes in nine samples of Silene littorea representing three color morphs (dark pink, light pink, and white) across three developmental stages in hopes of identifying the cause of flower color variation. We identified 29 putative paralogs for the 15 candidate genes in the ABP. We assembled complete coding sequences for 16 structural loci and nine of ten regulatory loci. Among these 29 putative paralogs, we identified 622 SNPs, yet only nine synonymous SNPs in Ans had allele frequencies that differentiated pigmented petals (dark pink and light pink) from white petals. These Ans allele frequency differences were further investigated with an expanded sequencing survey of 38 individuals, yet no SNPs consistently differentiated the color morphs. We also found one locus, F3h1, with strong differential expression between pigmented and white samples (\u3e42x). This may be caused by decreased expression of Myb1a in white petal buds. Myb1a in S. littorea is a regulatory locus closely related to Subgroup 7 Mybs known to regulate F3h and other loci in the first half of the ABP in model species. We then compare the mRNA-Seq results with petal biochemistry which revealed cyanidin as the primary anthocyanin and five flavonoid intermediates. Concentrations of three of the flavonoid intermediates were significantly lower in white petals than in pigmented petals (rutin, quercetin and isovitexin). The biochemistry results for rutin, quercetin, luteolin and apigenin are consistent with the transcriptome results suggesting a blockage at F3h, possibly caused by downregulation of Myb1a