Contextual diversity, not word frequency, determines word-naming and lexical decision times

Word frequency is an important predictor of word-naming and lexical decision times. It is, however, confounded with contextual diversity, the number of contexts in which a word has been seen. In a study using a normative, corpus-based measure of contextual diversity, word-frequency effects were eliminated when effects of contextual diversity were taken into account (but not vice versa) across three naming and three lexical decision data sets; the same pattern of results was obtained regardless of which of three corpora was used to derive the frequency and contextual-diversity values. The results are incompatible with existing models of visual word recognition, which attribute frequency effects directly to frequency, and are particularly problematic for accounts in which frequency effects reflect learning. We argue that the results reflect the importance of likely need in memory processes, and that the continuity between reading and memory suggests using principles from memory research to inform theories of reading

Construction of a DArT-seq marker–based genetic linkage map and identification of QTLs for yield in tea (Camellia sinensis (L.) O. Kuntze)

As the second most consumed non-alcoholic beverage, the tea plant (Camellia sinensis) has high economic value. Tea improvement efforts that largely target economic traits such as yield have traditionally relied on conventional breeding approaches. The tea plant’s perennial nature and its long generation time make conventional approaches time-consuming and labour-intensive. Biotechnology provides a complementary tool for accelerating tea improvement programmes through marker-assisted selection (MAS). Quantitative trait loci (QTLs) identified on linkage maps are an essential prerequisite to the implementation of MAS. QTL analysis was performed on yield data over 3 years (2010–2012) across two sites (Timbilil and Kangaita, in Kenya), based on two parental framework linkage maps arising from a population of 261 F1 progeny, derived from a reciprocal cross between GW Ejulu and TRFK 303/577. The maps contain 15 linkage groups each, this corresponds to the haploid chromosome number of tea (2n=2x=30). The total length of the parental maps was 1028.1 cM for GW Ejulu and 1026.6 cM for TRFK 303/577 with an average locus spacing of 5.5 cM and 5.4 cM, respectively. A total of 13 QTLs were identified over the three measurement years. The 13 QTLs had LOD values ranging from 1.98 to 7.24 and explained 3.4% to 12% of the phenotypic variation. The two sites had seven mutually detected QTLs.http://link.springer.com/journal/11295hj2022BiochemistryGeneticsMicrobiology and Plant Patholog