DNA Markers and FCSS Analyses Shed Light on the Genetic Diversity and Reproductive Strategy of Jatropha curcas L.

Diversity

Daria Gigliola Ambrosi³  Giulio Galla³  Marina Purelli¹  Tommaso Barbi¹  Andrea Fabbri¹  Sergio Lucretti²  Timothy Francis Sharbel⁴ 

[1] Geneticlab Srl, Via Corte Ferrighi 16/B, 36025 Noventa Vicentina, Vicenza, Italy; E-Mails:;ENEA, CR Casaccia, BIOTEC Section of Plant Genetics and Genomics, Via Anguillarese 301, 00123 Roma, Italy; E-Mail:;Laboratory of Plant Genetics and Genomics, College of Agriculture, University of Padova, Campus of Agripolis, Viale dell’Università 16, 35020 Legnaro, Padova, Italy; E-Mails:;Apomixis Research Group, Leibniz Institut für Pflanzengenetik und Kulturpflanzenforschung (IPK), Corrensstrasse 3, D-06466 Gatersleben, Germany; E-Mail:

关键词: Jatropha germplasm;    seed ploidy;    heterozygosity;    commercial varieties;   

DOI  :  10.3390/d2050810

来源: mdpi

【 摘 要 】

Jatropha curcas L. (2n = 2x = 22) is becoming a popular non-food oleaginous crop in several developed countries due to its proposed value in the biopharmaceutical industry. Despite the potentials of its oil-rich seeds as a renewable source of biodiesel and an interest in large-scale cultivation, relatively little is known with respect to plant reproduction strategies and population dynamics. Here, genomic DNA markers and FCSS analyses were performed to gain insights into ploidy variation and heterozygosity levels of multiple accessions, and genomic relationships among commercial varieties of Jatropha grown in different geographical areas. The determination of ploidy and the differentiation of either pseudogamous or autonomous apomixis from sexuality were based on the seed DNA contents of embryo and endosperm. The presence of only a high 2C embryo peak and a smaller 3C endosperm peak (ratio 2:3) is consistent with an obligate sexual reproductive system. Because of the lack of either 4C or 5C endosperm DNA estimates, the occurrence of gametophytic apomixis seems unlikely in this species but adventitious embryony cannot be ruled out. The investigation of genetic variation within and between cultivated populations was carried out using dominant RAPD and Inter-SSR markers, and codominant SSR markers. Nei’s genetic diversity, corresponding to the expected heterozygosity, was equal to H_e = 0.3491 and the fixation index as low as F_st = 0.2042. The main finding is that seeds commercialized worldwide include a few closely related genotypes, which are not representative of the original Mexican gene pool, revealing high degrees of homozygosity for single varieties and very low genetic diversity between varieties.

【 授权许可】

CC BY   
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