Project description:In order to identify variety-specific differences in defense response induction, Scavina 6 (Sca6) and Imperial College Selection 1 (ICS1) cacao plantlets were treated with 2mM SA or water as control and leaves of three developmental stages (A,C, E) were collected. This process was repeated 3 times yielding 32 samples, (Stage E ICS1 and Stage A Sca6 were collected only twice.) Averaging across developmental stages within each genotype, ICS1 had 436 up- and 601 down-regulated genes and Sca6 had 490 up- and 447 down-regulated genes (Benjamini-Hochberg p-value < 0.05). Analysis of gene annotations and Gene Ontology terms revealed that more PR genes and genes associated with defense response were up-regulated in ICS1, the more pathogen-susceptible genotype, while Sca6 had more genes associated with photosynthesis and energy generation. Same 17k unigene array as described in Mejía LC, Herre EA, Sparks JP, Winter K, García MN, Van Bael SA, Stitt J, Shi Z, Zhang Y, Guiltinan MJ, Maximova SN. 2014. Pervasive effects of a dominant foliar endophytic fungus on host genetic and phenotypic expression in a tropical tree. Frontiers in Microbiology 5.
Project description:Genome-Wide Analysis Reveals Divergent Patterns of Gene Expression During Zygotic and Somatic Embryo Maturation of Theobroma cacao L., The Chocolate Tree
Project description:Cocoa is a crop of cultural, nutritional and social importance in Latin America. Cocoa production is mainly supported by smallholders and is central for the food security of these farmer families. Despite being part of their everyday diet and an important source of antioxidants and other healthy bioactive compounds, cocoa cropping is also a solid source of stable incomes supporting the livelihood of farmer families. Water deficit stress is one of the main limiting factors affecting crop yields. The ability of plants to tolerate or recover from the effects associated with this abiotic stress is of immense importance in terms of improvement in the context of climate change. Despite the emergence of functional genomics and phenotyping tools to approach these responses, many of these mechanisms are still little understood for many tropical food crops such as cocoa. For a transcriptomic analysis were selected 2 cocoa genotypes, from a hydric stress assay established in a greenhouse. 5-month-old plants of T. cacao of the genotypes EET 8 and TSH565 were tested for water deficit trial. A divided plot experimental design was applied: the hydric state of the 2 genotypes was evaluated with two levels: field capacity and water deficit by irrigation suspension during a period that generates severe stress (Leaf Water Potential of -3.0 Mpa). The irrigation suspension lasted 52 days.
