Brief Communications

It remains unclear how post-transcriptional gene silencing in plants discriminates aberrant RNAs from canonical mRNAs. Now, a study shows that the poly(A) tail of canonical mRNAs blocks RDR6 from converting them into the substrates for gene silencing.

Plants evolved NLR sensors to detect bacterial effectors or their activity. A genetic analysis in Arabidopsis expands the role of the ZAR1 NLR protein. ZAR1 recognizes effector HopF2a through its association with pseudokinase ZRK3, inducing resistance without hypersensitive response.

CRISPR–Cpf1 has emerged as an effective genome editing tool in animals. Now, a study shows that this system can edit plant genomes at nearly 100% efficiency at independent sites. Moreover, it can be repurposed for modulating plant transcriptome.

Mutualisms are common in nature. In Fiji, a species of ant selects, disperses and fertilizes an epiphytic plant in an exclusive symbiosis. This represents a novel example of plant farming by ants.

The authors identify novel NEGATIVE GRAVITROPIC RESPONSE OF ROOTS genes in Medicago and Arabidopsis. Mutants display a spectacular phenotype: gravity is still perceived, but the direction of growth is reversed: roots always grow upwards.

Photorespiration is a major light-dependent metabolic pathway that consumes O₂ and produces CO₂. Quantitative isotopic labelling experiments with sunflower leaves suggest that the O₂/CO₂ stoichiometric coefficient of photorespiration at the leaf level is very close to 2 under typical photorespiratory conditions.

Wheat stem rust is a devastating fungal disease, especially since the emergence of the virulent Ug99 lineage. An efficient resistance gene, encoding a CC–NB–LRR, is identified in a highly diverse locus of rye, and is effective against Ug99.

Auxin-binding protein ABP1 has been characterized as a secreted receptor for the hormone. Embryonic lethality of insertion mutant abp1-1 hinted at a central role in development. However, this lethality is in fact due to deletion of neighbour gene BSM.

Mimicry, deception and sensory exploitation of animals by plants is controversial, especially for seed dispersal. A field experiment in a South African nature reserve suggests that the large brown, round, strongly scented seeds of Ceratocaryum argenteum that emit many volatiles found to be present in herbivore dung, attract dung beetles that roll and bury them.

Transient assays and transgenic experiments demonstrate that sgRNA/Cas9 constructs targeting the bean yellow dwarf virus inhibit the accumulation of the virus and confer resistance in transgenic N. benthamiana plants.

Transient assays and transgenic experiments demonstrate that sgRNA/Cas9 constructs targeting the beet severe curly top virus (BSCTV) inhibit the virus accumulation and confer resistance in Arabidopsis and N. benthamiana.

Orchid seeds are conventionally thought to be wind dispersed. However, extensive observation with motion sensor cameras shows that birds such as the brown-eared bulbul eat and disperse the seeds of at least one orchid, Cyrtosia septentrionalis.