Integr Comp Biol. 2025 May 8:icaf028. doi: 10.1093/icb/icaf028. Online ahead of print.

ABSTRACT

Climate change is simultaneously increasing atmospheric carbon dioxide concentrations ([CO2]) and temperatures. We conducted a multi-factorial growth chamber experiment to examine how these climate change factors interact to influence the expression of ecologically-relevant traits, clines in these traits, and natural selection on morphology and phenology of diverse accessions of Boechera stricta (Brassicaceae) sourced from a broad elevational gradient in Colorado, USA. Plastic shifts in a key allocation trait (root mass fraction) in response to temperature accord with the direction of selection for probability of flowering, indicating that plasticity in this trait could be adaptive. However, plasticity in a foliar functional trait (leaf dry matter content) in response to temperature and [CO2] did not align with the direction of selection, indicating that plasticity could reduce fitness based on plant carbon allocation strategies. For another ecologically-important phenotype, selection favors resource acquisitive trait values (higher specific leaf area) under elevated [CO2] and resource conservative trait values (lower specific leaf area) at lower [CO2], despite the lack of plasticity in this trait. This pattern of selection counters published reports that elevated [CO2] induces low specific leaf area but could enable plants to reproduce across a greater period of the growing season under increasingly warm climates. Indeed, warmer temperatures prolonged the duration of flowering. This plasticity is likely adaptive, as selection favored increased flowering duration in the higher temperature treatment level. Thus, the two major results that emerged from our study are that climate change could impose novel and unanticipated patterns of natural selection on plant traits and that plasticity in these traits can be a maladaptive response to stress.

PMID:40338630 | DOI:10.1093/icb/icaf028

Phytopathology. 2025 May 7. doi: 10.1094/PHYTO-01-25-0028-R. Online ahead of print.

ABSTRACT

Root-knot nematodes (RKN; Meloidogyne spp.) are among the most widespread and damaging plant-parasitic nematodes known. While M. incognita is the most prevalent RKN species, other species, including M. enterolobii, M. floridensis, and M. haplanaria have recently been detected in multiple Georgia, USA, vegetable fields. Producers use chemical nematicides to manage M. incognita populations because most vegetable crops do not have effective RKN host resistance. We evaluated the effects of sublethal doses of non-fumigant nematicides-fluazaindolizine, fluensulfone, fluopyram, and oxamyl-on motility, egg hatching, and reproduction of these four RKN species. In vitro behavioral response assays revealed significant variation in motility between species, with M. enterolobii being the less sensitive to the evaluated nematicides. Root-knot nematode population response in greenhouse conditions indicated that all the nematicides impaired the reproduction of the evaluated Meloidogyne species. While most nematicides displayed a strong effect on reducing the egg-hatching, fluazaindolizine appeared to have a poor effect on suppressing the egg-hatching across all RKN species. No differences were observed among Meloidogyne species in their egg-hatching responses to nematicides. In this study, we conducted the first comprehensive evaluation of these nematicides on motility, reproduction, and egg hatching in these RKN species. This study enhances our understanding of the species-specific responses of different Meloidogyne spp. to non-fumigant nematicides.

PMID:40331798 | DOI:10.1094/PHYTO-01-25-0028-R

Nat Commun. 2025 May 6;16(1):4184. doi: 10.1038/s41467-025-59522-7.

ABSTRACT

High temperatures compromise crop productivity worldwide, but breeding bottlenecks slow the delivery of climate-resilient crops. By investigating tomato fruit set under high temperatures, we discover a module comprising two linked genes, THERMOSENSITIVE PARTHENOCARPY 4a (TSP4a) and TSP4b, which encode the transcriptional regulators IAA9 and AINTEGUMENTA (ANT), respectively, to control thermosensitive parthenocarpy. TSP4a and TSP4b form a positive feedback loop upon heat stress to repress auxin signaling in ovaries. Natural TSP4a and TSP4b alleles bear regulatory-region polymorphisms and are differentially expressed to overcome the trade-off between fruit set and wider plant development. Gene editing of the TSP4a promoter and TSP4b 3′ UTR in open-chromatin regions results in expression down-regulation, increased parthenocarpy without yield penalties and maintenance of fruit-sugar levels without broad auxin-related pleiotropic defects in greenhouse-grown plants. These mechanistic insights into heat-induced parthenocarpy and auxin signaling in reproductive organs demonstrate breeding utility to safeguard tomato yield under warming scenarios.

PMID:40328814 | DOI:10.1038/s41467-025-59522-7

J Biol Chem. 2025 Apr 30:108566. doi: 10.1016/j.jbc.2025.108566. Online ahead of print.

ABSTRACT

DectiSomes are drug-loaded liposomes coated with pathogen receptors, such as the C-type lectins (CTL) Dectin-2 (D2) and Dectin-3 (D3, MCL). Floating on the surface of DectiSomes, the carbohydrate recognition domains (CRDs) of these CTLs form dimers that bind their cognate oligoglycan ligands. We have shown previously that amphotericin B (AmB)-loaded DectiSomes, D2-AmB-LLs and D3-AmB-LLs, are effective at binding and killing diverse pathogenic fungi. The best-known ligands of Dectin-2 and Dectin-3 in the Candida albicans cell wall and exopolysaccharide matrix include a wide variety of oligomannans. When D2-AmB-LLs or D3-AmB-LLs were labeled in their lumen with complementary green and red fluorescent proteins, Venus and mCherry, they bound the same overlapping regions of oligoglycans in C. albicans colonies. By contrast, when D2-AmB-LLs and D3-AmB-LLs were labeled on their membrane surfaces with complementary pairs of the small fluorophores FITC and Rhodamine B or with Venus and mCherry, they bound mostly non-overlapping sets of ligands. When the Dectin-2 and Dectin-3 proteins were labeled with the complementary pairs of FITC and Rhodamine, they also bound primarily distinct ligands. We proposed several models to explain these alterations in Dectin and DectiSome ligand specificity. These findings also raise important questions about the ligand binding properties of immuno-liposomes.

PMID:40316022 | DOI:10.1016/j.jbc.2025.108566