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Frosty pod rot (FPR), caused by Moniliophthora roreri (MR), is one of the most important diseases of cacao, causing losses of up to 90% in areas where it is present. A limited number of resistant clones have been identified, but additional sources of disease resistance are being sought by breeding programs. RNA-sequencing was used to identify differences in constitutive (mock-inoculated) and pathogen-induced gene expression in cacao pods from trees resistant and susceptible to MR. The greatest number of differentially expressed genes (DEGs) (n=2,039) was identified in susceptible material following inoculation with MR (7 days post inoculation), with the most common pathway categories being cell growth/death (n=102), signaling (n=308), and carbohydrate metabolism (n=141). Resistant material showed little overall change in gene expression (5 DEGs) following pathogen inoculation, suggesting that infection had not become established. For this reason, differences in constitutive gene expression are likely to provide the most relevant information on FPR resistance in this study. In the absence of the pathogen, 144 genes were expressed at a higher level in the resistant material, and 265 at a higher level in the susceptible material. The genes most highly upregulated in resistant material encode for disease resistance proteins in the leucine rich repeat family and cysteine-rich receptor-like protein kinases. Ten DEGs were located within QTL on chromosomes 2, 7, and 9 previously associated with FPR resistance in this population. This study provides the first analysis of constitutively expressed genes contributing to FPR resistance and identifies significant genes within known disease resistance QTL.

We present the whole genome sequences of 56 wild Erythroxylum species from Africa, China, and the American tropics. Deep Illumina sequencing was performed on a single leaf of each voucher. We de novo assembled sequence reads and then identified and used conserved regions across all preassemblies join contigs in a finishing step. The raw and assembled data is publicly available via Genbank.

The flowering plant genus Erythroxylum contains approximately 300 species, including the economically and socially consequential crops called coca. We present the genome sequences of Erythroxylum coca and E. novogranatense, two cultigens produced for medicinal and quotidian use in the Andes and Amazon regions of South America, as well as the international cocaine industry. Sequencing was performed on an Illumina X-Ten platform, and reads were assembled by a de novo method followed by finishing via comparison with several species from the same genus. The BioProject, raw and assembled data can be accessed in GenBank for E. coca (PRJNA676123; JAJMLV000000000) and E. novogranatense (PRJNA675212; JAJKBF000000000).

Examining verbal memory recall from a speech production standpoint can greatly contribute to the understanding of both processes. The existence of the segment as the minimal unit of articulation, already shown in the naming task, has important implications for how recall might occur in verbal recall tasks. Specifically, the initial segment of a target response might be retrieved and articulated before the remainder of the word is retrieved, leading to incremental articulation of the target word with the segment as minimal unit of articulation. This possibility was explored in two experiments by examining the initial segment durations of responses during recall when blocks were either heterogeneous or homogeneous with respect to the initial segment. Incremental articulation based on the segment was found to occur during the recall task to a greater degree in homogeneous blocks in both experiments. Experiment 2 showed no strong evidence for a relation between interference and incremental articulation. Additional evidence for the segment as minimal unit of articulation was found, extending this result beyond the naming task. Prior techniques used to explore the time-course of recall, such as interresponse time, must be revised. Through exploring recall using this novel paradigm inspired by speech production research, new methods can be utilized to examine established recall effects such as the phonological similarity effect.