Letters in 2020

Dichotomous root branching evolved in both lycophytes and euphyllophytes, followed by lateral branching in separate extant lineages during the Devonian and Carboniferous periods, illustrating extreme cases of divergent evolution.

Previous studies showing that mast seeding was synchronized at large scales were constrained to hundreds of kilometres, but this continental-scale study shows that such events are asynchronous, driving spatial and temporal impacts for a wide range of species.

Fire has shaped plant life for millions of years, but flammability as an inherited trait has been difficult to discern. This Letter reveals several predictors in the evolution of plant flammability.

The AHL15 transcription factor is a repressor of axillary meristem maturation. AHL15 is downstream of flowering genes and prolongs the vegetative growth and longevity of plants, particularly monocarps such as Arabidopsis thaliana.

Mitochondria ribosomes translate essential mRNAs encoded by mitochondrial genomes. The cryo-EM structure of the 78S mitoribosome from cauliflower shows plant-specific pentatricopeptide repeat proteins binding rRNAs expanded over those of animals.

Analyses of Arabidopsis temperature-sensitive genic male sterility lines show that slowing development overcomes microspore defects and restores fertility, suggesting that low temperature reverses their fertility as a general factor by slowing development.

In plant communities, co-occurring species compete for resources such as mineral nutrients under limited supply. Here, the researchers found that a major mineral nutrient, phosphorus, was taken up by co-occurring plants in species-specific proportions of different forms, which may drive the development of community biodiversity.

Restoring ecosystems depends on the cultivation of native plants to balance biodiversity with agricultural needs. This Letter finds that despite being overlooked for commercial varieties, 85% of Mediterranean native annuals could be used in olive groves for nature-based agronomy.

The cyanobacterial chlorophyll, Chl f, absorbs far-red light. Mutation of two residues in a subunit of photosystem II converts it to a Chl f synthase. This ‘super-rogue’ photosystem might improve photosynthetic efficiency in low light.

Arabidopsis plants try to escape shade or competitor proximity by growing faster. The authors identify sulfotransferase ST2a as a link between light perception and growth increase through inactivation of jasmonates.

Different from the degradative microbial laccases, plant laccases are involved in lignin biosynthesis and the regulation of plant development. The catalytic structure of plant laccases has remained enigmatic until now. Here, a maize laccase, ZmLac3, is characterized in complex with two types of lignin monomers.

Genome assemblies of two aquatic species, prickly waterlily and rigid hornwort, clarify the early diversification and phylogeny of plants. Multiple independent polyploidization events are inferred in each of the five major angiosperm clades.

Immune receptor FLS2 perceives flagellin epitopes from many bacterial pathogens, but not from well-known Agrobacterium tumefaciens. The authors find a natural FLS2 in a wild grape species that can perceive this modified flagellin.

Plants store the vast majority of their DNA in the nucleus, like all other eukaryotes, but also possess two sets of organellar genomes in mitochondria and plastids. Now, researchers have employed haploid inducers to generate reciprocal cybrids to disentangle the specific contributions of organellar variations to plant performance.