Volume 6 Issue 6, June 2020

Plant elicitor peptides (Peps) enhance immunity against diverse pathogens. Engineering a naturally occurring rhizobacterium to deliver Peps to the plant root system offers a new opportunity in integrated pest management.

CRISPR–Cas technology now enables chromosome structural engineering in plants.

Seed germination is tightly regulated so that it only occurs in optimal environmental conditions; for root parasitic plants, this is the presence of a potential host plant revealed by strigolactone exudates. New research shows that, unexpectedly, this response to strigolactone bypasses the core gibberellin-dependent pathway for germination.

The need for increased crop yields has led to growing interest and research in agricultural intensification, which has a myriad of environmental impacts. Intercropping can bring the benefits of intensification within a reasonable footprint.

The critical epigenetic features that characterize remethylable and non-remethylable loci in Arabidopsis determine the capacity of RNA-directed DNA methylation (RdDM)-targeted genomic regions to form stable epialleles.

Plants need to respond swiftly against attacks, but when pathogen pressure is weak, defence genes must be repressed as they impede development and growth. Three RNA helicases are now found to control decapping-dependant mRNA decay and negatively regulate plant immunity.

This Perspective summarizes recent advances made on in planta haploid induction systems and how these advances contribute to our understanding of plant reproduction and innovations of plant breeding.

An efficient and multiplexed in planta gene editing approach is developed by infecting Cas9 transgenic plants with an RNA virus that expresses single guide RNAs carrying sequences that confer cell-to-cell mobility.

Potato roots can be infected by parasitic nematodes that cause galls. Here the authors express a plant peptide in soil bacteria that stimulates plant immunity. Pre-treatment of potato roots with the modified bacteria protects the plants from nematodes.

Populus has young sex chromosomes despite ancient dioecy. This study shows that the ARR17 gene functions as a sex switch, triggering female development when on and male development when off. This single-gene system enables dynamic evolution of poplar sex chromosomes.

Clustered regularly interspaced short palindromic repeats (CRISPR)–CRISPR-associated protein (Cas) technology was used to induce heritable reciprocal chromosomal translocations in the Mb range in Arabidopsis, providing new possibilities to modify chromosomes and break linkage drag in plant breeding.

The parasitic plant Striga hermonthica germinates when it senses strigolactones (SLs). By expressing Striga SL receptors in Arabidopsis, the authors show that the SL pathway can regulate germination independently of gibberellin signalling.

Intercropping can provide for agricultural intensification within a sustainable footprint. This study of Chinese methods finds yields four times greater than intercropping outside China with less land and fertilizer use.

A study shows that RNA-directed DNA methylation target loci in Arabidopsis can be classified into two groups—remethylable and non-remethylable loci—characterized by different histone and DNA methylation marks that determine the ability of these loci to form stable epialleles.

Defence genes must be switched off when pathogen pressure is weak to favour growth and development programmes. Three RNA helicases participate in this repression by controlling how stress-specific mRNAs are stabilized and translated.

The shape of plant organs shows low variability. Sepals of the same age look the same. Here the authors identify one transcription factor (DRMY1) crucial for sepal size reproducibility, and its effect on initiation timing and growth of the organ.

The authors investigate the mechanisms behind floral arrest in Arabidopsis. Despite what was previously believed, they show that it is not a global process but a locally regulated mechanism, driven by the export of auxin from fertile fruits.

RuBisCO is believed to be the most abundant enzyme on earth, and catalyses a critical step in carbon fixation. Assisted by different assembly factors, including Raf1, RuBisCO assembles into the holoenzyme comprising eight large subunits (RbcL) and eight small subunits (RbcS). Here, the researchers resolve high-resolution protein structures of the cyanobacterial RuBisCO octameric complex that reflect different steps of its assembly.