Identification of QTL markers contributing to plant growth, oil yield and fatty acid composition in the oilseed crop Jatropha curcas L.

Abstract

BackgroundEconomical cultivation of the oilseed crop Jatropha curcas is currently hampered in part due to the non-availability of purpose-bred cultivars. Although genetic maps and genome sequence data exist for this crop, marker-assisted breeding has not yet been implemented due to a lack of available marker–trait association studies. To identify the location of beneficial alleles for use in plant breeding, we performed quantitative trait loci (QTL) analysis for a number of agronomic traits in two biparental mapping populations.ResultsThe mapping populations segregated for a range of traits contributing to oil yield, including plant height, stem diameter, number of branches, total seeds per plant, 100-seed weight, seed oil content and fatty acid composition. QTL were detected for each of these traits and often over multiple years, with some variation in the phenotypic variance explained between different years. In one of the mapping populations where we recorded vegetative traits, we also observed co-localization of QTL for stem diameter and plant height, which were both overdominant, suggesting a possible locus conferring a pleotropic heterosis effect. By using a candidate gene approach and integrating physical mapping data from a recent high-quality release of the Jatropha genome, we were also able to position a large number of genes involved in the biosynthesis of storage lipids onto the genetic map. By comparing the position of these genes with QTL, we were able to detect a number of genes potentially underlying seed traits, including phosphatidate phosphatase genes.ConclusionsThe QTL we have identified will serve as a useful starting point in the creation of new varieties of J. curcas with improved agronomic performance for seed and oil productivity. Our ability to physically map a significant proportion of the Jatropha genome sequence onto our genetic map could also prove useful in identifying the genes underlying particular traits, allowing more controlled and precise introgression of desirable alleles and permitting the pyramiding or stacking of multiple QTL.Electronic supplementary materialThe online version of this article (doi:10.1186/s13068-015-0326-8) contains supplementary material, which is available to authorized users.

Fatty Acid Diversity is Not Associated with Neutral Genetic Diversity in Native Populations of the Biodiesel Plant Jatropha curcas L.

“…altitude, a variable correlated with climatic factors important at the local scale) and not with genetic differences obtained with neutral genetic markers. For this reason and previously described geographical variability in chemical patterns, and partial genetic control of fatty acids obtained with QTL, we suggest that plantation design strategies for J. curcas should consider that genotype‐environment interactions contribute to the chemical variation of oil seed in J. curcas .…”

“…One possible explanation is that the SSRs are neutral genetic markers commonly used for studies of molecular diversity in non‐codifying regions of the genome; in contrast, the genetic variation represented in the profile of fatty acids or in phorbol esters is not neutral and could be exposed to natural selection by factors particular to each site. King et al . showed that fatty acid variation in J. curcas is under genetic control of several QTL, also, this variation is associated with environmental differences.…”

“…the composition of the oil is highly heritable, which suggests limited environmental influence. In this sense, King et al . showed that the fatty acid composition and oil yield are under partial genetic control of a few quantitative trait loci (QTL).…”

<i>Jatropha curcas L</i>. and <i>J. macrocarpa</i> Griseb: Seed Morphology, Viability, Dormancy, Germination and Growth of Seedlings

“…Some years ago it has been known that biodiesel obtains from J. curcas and J. macrocarpa meets international standards [2] [4] and is reported to exhibit better performance than conventional petroleum diesel [5]. However, the potential of J. curcas as a biofuel plant is limited by its low seed production [6]. Despite the clear evidence of the abundant aboveground biomass generated by J. curcas, these data are not indicative of high seed productivity [7].…”

Suitability of Jatropha curcas L. as Source of Oil and Biodiesel Production in Benue State in Nigeria

“…Though Jatropha curcas L grows naturally in Africa, its cultivation on an industrial scale is a very recent business enterprise for which little reliable scientific data exists either for management or environmental assessment. Jatropha curcas L. is made popular as unique candidate among renewable energy sources due its peculiar features like speedy growth, drought forbearance and easy propagation, higher oil content than other oil crops, small gestation period, wide range of environmental adaptation, the optimum plant size and structure [8]. Based on these interesting properties, potentials and hyped claims on Jatropha curcas L, a lot of investors, policy makers and clean development mechanism project developers are interested in Jatropha curcas L to tackle the challenges of energy supply and Green House Gas (GHG) emission reduction [9].…”