Mutation of a bHLH transcription factor allowed almond domestication

Wild almond species accumulate the bitter and toxic cyanogenic diglucoside amygdalin. Almond domestication was enabled by the selection of genotypes harboring sweet kernels. We report the completion of the almond reference genome. Map-based cloning using an F1 population segregating for kernel taste led to the identification of a 46-kilobase gene cluster encoding five basic helix-loop-helix transcription factors, bHLH1 to bHLH5. Functional characterization demonstrated that bHLH2 controls transcription of the P450 monooxygenase–encoding genes PdCYP79D16 and PdCYP71AN24, which are involved in the amygdalin biosynthetic pathway. A nonsynonymous point mutation (Leu to Phe) in the dimerization domain of bHLH2 prevents transcription of the two cytochrome P450 genes, resulting in the sweet kernel trait.

Towards A Pan–Cultural Personality Structure: Input from 11 Psycholexical Studies

The purpose of the present study is to find the common kernel of different trait taxonomic studies and find out how the individual structures relate to this common kernel. Trait terms from 11 psycholexically based taxonomies were all translated into English. On the basis of the commonalities in English, the 11 matrices were merged into a joint matrix with 7104 subjects and 1993 trait terms. Untranslatable terms produced large areas with missing data. To arrive at the kernel structure of the joint matrix, a simultaneous component analysis was applied. In addition, the kernel structures were compared with the individual taxonomy trait structures, obtained via principal component analysis. The findings provide evidence of a structure consisting of three components to stand out as the core of the taxonomies included in this study; those components were named dynamism, affiliation, and order. Moreover, the relations between these three kernel components and those of a six–component solution (completing the six–factor model) are provided. Copyright © 2014 European Association of Personality Psychology

Genetic Studies in Peach: Inheritance of Sweet Kernel and Male Sterility

Inheritance of the sweet kernel trait was studied in F1 and F2 families generated by crossing `Summer Beaut' nectarine (sweet kernel) with `Ellerbe' and `Biscoe' peach. F1 plants showed bitter kernel. Segregation in the F2 fit a 3 bitter : 1 sweet phenotypic ratio, suggesting that sweet kernel is controlled by a single recessive gene, for which the symbol sk is proposed. Sweet kernel (sk) was linked to nectarine (g) at a map distance of 12 cM. Seed bitterness phenotype is controlled by the genotype of the maternal tree and not the genotype of the individual embryo. Inheritance of male sterility derived from plant introduction (PI) 240928 and allelism of male sterile genes found in `Chinese Cling' and `White Glory' were investigated. Analysis of F1, F1 open-pollinated, and BC1 families derived from crossing PI 240928 with six different wild-type cultivars showed that male sterility in PI 240928 is controlled by cytoplasmic factors. Allelism studies showed that the male-sterile gene found in `White Glory' is not allelic to ps found in `Chinese Cling', and hence is designated ps2.

Inheritance and Linkage Studies in Peach

Inheritance of male sterility in peach [Prunus persica (L.) Batsch] Plant Introduction (PI) 240928 was investigated. Crosses of PI 240928 with five wild-type clones yielded all male-sterile offspring, indicating dominant gene action. Inheritance of the sweet kernel trait in peach was studied in F1 and F2 progeny of `Summer Beaut' nectarine (sweet kernel) × `Biscoe' peach (bitter kernel). All four F1 progeny were bitter. Segregation in an F2 of 80 progeny fit a ratio of 3 bitter: 1 sweet. We propose that the gene controlling the sweet kernel trait be designated sk. Sweet kernel (sk) was linked to nectarine (g) at a map distance of 17 cM. Evaluation of the peach PI collection showed that PI 129678 (`Stanwick' nectarine) and PI 34685 (`Quetta' nectarine) were the only clones with a sweet kernel. Crosses between `Davie II' and `Honeyglo' nectarine (dwdw) confirmed that the gene conferring the dwarf phenotype in progeny of `Davie II' is non-allelic to dw.