Mechanism of resistance to Dutch elm disease, MADS goes genomic in conifers and floral symmetry and pollination – This Week in Annals of Botany

Lots of groundbreaking new science in Annals of Botany this week:

Host responses and metabolic profiles of wood components in Dutch elm hybrids with a contrasting tolerance to Dutch elm disease
Changes occurring in the macromolecular traits of cell wall components in elm wood following attack by Ophiostoma novo-ulmi, the causative agent of Dutch elm disease, are poorly understood. This study compares host responses and the metabolic profiles of wood components for two elm hybrids, ‘Groeneveld’ (a susceptible clone) and ‘Dodoens’ (a tolerant clone), that have contrasting survival strategies on infection with the current prevalent strain of Dutch elm disease.

MADS goes genomic in conifers: towards determining the ancestral set of MADS-box genes in seed plants
MADS-box genes comprise a gene family coding for transcription factors. This gene family expanded greatly during land plant evolution such that the number of MADS-box genes ranges from one or two in green algae to around 100 in angiosperms. Given the crucial functions of MADS-box genes for nearly all aspects of plant development, the expansion of this gene family probably contributed to the increasing complexity of plants. However, the expansion of MADS-box genes during one important step of land plant evolution, namely the origin of seed plants, remains poorly understood due to the previous lack of whole-genome data for gymnosperms.

The influence of floral symmetry, dependence on pollinators and pollination generalization on flower size variation
This study suggests that the relationship between flower size variation and floral symmetry may be influenced by population-dependent factors, such as ecological generalization and species’ dependence on pollinators.