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Siles, L.

Publications and source records attributed to Siles, L..

3 recordsLinked to original sources

Associative transcriptomics in Brassica napus suggests a role for Arabidopsis Response Regulator orthologs in seedling vigour

Background and AimsOptimal seedling vigour determines successful crop establishment and its ability to overcome abiotic and biotic threats. Seedling vigour is regulated by several different factors, genetic, physiological, environmental, post-harvest storage, making it challenging to fully elucidate. The aim of this study was to dissect the genetic basis of post-germinative seedling traits and its implications in seedling establishment success in Brassica napus. MethodsA B. napus diversity set panel was used to phenotype seedling establishment traits in the soil including days to emergence, days to appearance of first and second true leaves, and days to reach 25% and 50% cotyledon expansion. An associative transcriptomics analysis was performed to identify the genetic factors regulating seedling establishment. Key ResultsThe study of different phenotypic traits highlighted the relevance of scoring more than one trait to determine good performers. Gene expression markers significantly associated with the studied traits were associated with the cytokinin signalling pathway and photomorphogenesis. Gene expression markers for orthologues of Arabidopsis thaliana RESPONSE REGULATOR 4 and 5 (ARR4, ARR5) were significantly associated with days to appearance of second leaf. SUPPRESSOR OF PHYA-105 1 (SPA1) orthologues were associated with cotyledon area, meanwhile ALTERED SEED GERMINATION 7 (ASG7) and PSEUDO-RESPONSE REGULATOR 7 (PRR7) orthologues were associated with days to emergence, suggesting a complex and interconnected regulatory pathway controlling several traits of seedling establishment. ConclusionsThese results uncovered promising genes that appear to work in a complex and interconnected manner controlling several post-germinative seedling traits affecting final seedling establishment speed.

plant biology↗

Uncovering the ideal plant ideotype for maximising seed yield in Brassica napus

Seed yield is a complex trait for many crop species including oilseed rape (Brassica napus), the second most important oilseed crop worldwide. Studies have focused on the contribution of distinct factors in seed yield such as environmental cues, agronomical practices, growth conditions or specific phenotypic traits at the whole plant level, such as number of pods in a plant. However, in spite of the immense economic importance of oilseeds, none of these studies have comprehensively analysed individual traits and their combined contribution to seed yield. Here, we describe the analysis and contribution of 33 phenotypic traits within a B. napus diversity set population and their trade-offs on seed yield not only at the whole plant level but also the less studied female reproductive traits. Our results revealed that both winter and spring oilseed rape; the two more economically important oilseed rape groups in terms of oil production; were found to share a common dominant reproductive strategy for seed yield. In this strategy the main inflorescence is the principal source of seed yield, producing a good number of ovules, a large number of long pods with a concomitantly high number of seeds per pod. We observed that winter oilseed rape opted for more reproductive strategies than spring oilseed rape, presenting more environmental flexibility to maximise seed yield. Overall, we conclude that, oilseed rape adopts a similar strategy that is key for maximal seed yield and propose an ideal ideotype highlighting crucial phenotypic traits that could be potential targets for breeding. One sentence summaryThe main florescence is the principal source of seed yield in winter and spring oilseed rape, with winter oilseed rape following several reproductive strategies to maximise seed yield.

plant biology↗

Big data from small tissues: extraction of high-quality RNA for different plant tissue types during oilseed Brassica spp. seed development for RNA-Sequencing

Obtaining high-quality RNA for gene expression analyses from different seed tissues is challenging due to the presence of various contaminants, such as polyphenols, polysaccharides and lipids which interfere with RNA extraction methods. At present, the available protocols for extracting RNA from seeds require high amounts of tissue and are mainly focused on extracting RNA from whole seeds. However, extracting RNA at the tissue level enables more detailed studies regarding tissue specific transcriptome during development. Seeds from heart stage embryo to mature developmental stages of Brassica napus and B. oleracea were sampled for isolation of the embryo, endosperm and seed coat tissues. Ovules and gynoecia wall tissue were also collected at the pre-fertilization stage. After testing several RNA extraction methods, E.Z.N.A. Plant RNA Kit and Picopure RNA Isolation kit extraction methods with some modifications, as well as the use of PVPP for seed coats and endosperms at green stages, resulted in high RNA concentrations with clear 28S and 18S bands and high RIN values. Here, we present efficient and reliable RNA extraction methods for different genotypes of Brassica spp for different tissue types during seed development. The high-quality RNA obtained by using these methodologies is suitable for RNA-Sequencing and gene expression analyses.

plant biology↗