AoB Plants最新文献

Papaver somniferum (poppy) is a traditional ingredient in Central and Eastern European cuisine and an important oilseed crop of the region. Since the main threat to stable poppy yield is pathogen infection, a detailed understanding of its defence mechanism is essential. The first robust layer of plant immunity, which plays a crucial role in combating pathogens, is pattern-triggered immunity (PTI). Here, we provide the first comprehensive insights into PTI in poppy. We selected four poppy varieties used in the food industry and investigated their response to various previously described peptide elicitors. Among all tested peptides, flg22 induced the most robust reactive oxygen species (ROS) burst, as well as triggering putative mitogen-activated protein kinase phosphorylation and seedling growth inhibition in all selected cultivars. We identified PsWRKY22 and PsPR2 as candidate marker genes suitable for monitoring poppy PTI responses. The tested poppy cultivars have low levels of salicylic acid. Callose accumulation was triggered by wounding but not by flg22. When studying PTI in plants, wounding is a challenge that needs to be considered, as it can obscure potential PTI responses. Our findings highlight conserved aspects of poppy immunity and the challenges of studying its PTI. The established pipeline facilitates improving our understanding of poppy immunity and has the potential for widespread application in breeding and improving selection for broad-spectrum disease resistance provided by enhanced PTI.

Gene-editing tools enable precise, targeted genome modifications, providing new approach for the rapid and sustainable improvement of tea plant (Camellia sinensis (L.) Kuntze). Developing such an approach is especially important due to the perennial nature and complex genetics of the tea plant, which make traditional breeding slow and inefficient. To validate a gene editing protocol in the elite local tea cultivar Kolkhida three candidate genes were selected. Two guide RNAs (gRNAs) were designed for each gene, and corresponding constructs for targeted genome modification in tea were generated. Successful modifications of the target sequences in cv. Kolkhida tea protoplasts were achieved for all three target genes. The high mutagenic efficiency of the selected gRNAs was observed for two out of three genes, including induction of precise deletions between target motifs. gRNAs were delivered in protoplasts via co-transfection technique, and combined gRNA activity was observed when transfection efficiency exceeded 28%. The genome modification method for tea protoplasts established in this study can serve as a screening protocol to evaluate the in vivo efficiency of different genome editing approaches in the tea plant.

The study of floral biology has long attracted the attention of plant biologists because of its enormous basic and applied implications, spanning from identification of the ecological and genetic drivers of flowering plant evolution to the performance of crop yields in agricultural systems. In a rapidly changing planet, floral biology studies acquire an utmost importance to comprehend the multiple ecological, economical, and social challenges ahead for humanity. In this special issue, we gathered a collection of papers dealing with various ecological, genetic, and evolutionary aspects of floral biology. This special issue encompasses 12 papers showcasing theoretical and empirical research on plant-pollinator communities, pollinators and pollination modes, floral ecology and genetics at various spatial scales, and the effects of warming-induced abiotic stress on floral biology. Overall, this special issue highlights the importance of long-term spatial and temporal studies, which require a collaborative effort of the research community, and the development of experimental approaches to quantify in detail the effects of human-induced abiotic stress, such as droughts and heatwaves, on plant reproduction.

Examining long-term trends in climate-driven flowering time shifts provides valuable insights, but can mask dynamic interannual variation that may reveal the capacity for short-term phenological responses. We examined the interannual and intraspecific dynamics of flowering time shifts in Triodanis perfoliata (Campanulaceae) using a comprehensive dataset with a total 1493 vetted records spanning 1895-2022 across the contiguous USA. Here, we build on previous work demonstrating long-term flowering time advances (Berg et al., An examination of climate-driven flowering-time shifts at large spatial scales over 153 years in a common weedy annual. Am J Bot 2019;106:1435-43.). Specifically, we examined the influence of interannual temperature variation on flowering time, and explored how these responses varied across a broad geographic range. We found a significant correlation between interannual spring temperature variation and flowering time, with cooler springs associated with delayed flowering and warmer springs associated with earlier flowering. Critically, we found that the magnitude of this relationship varied among T. perfoliata populations, with individuals in cooler, higher latitude regions showing less sensitivity to interannual temperature variation than those in warmer, lower latitude regions. This differential sensitivity suggests potential adaptive or plastic responses to local climatic conditions and may have implications for gene flow and the long-term ecological and evolutionary trajectory of T. perfoliata populations. This study highlights the importance of considering both long-term trends and interannual variation in phenological research, and emphasizes the need for further investigation into the drivers and consequences of intraspecific variation in phenological sensitivity.

Habitat variability critically influences plant reproductive strategies and pollinator attributes. However, studies on intraspecific variation in vegetative and floral traits, pollinator attributes, and seed traits remain limited in the context of small-scale habitat heterogeneity, particularly meadows interspersed with sandy patches. On the Tibetan Plateau, discrete sandy patches (some as small as 10 m²) occur within alpine meadows. We hypothesized that distinct plant reproductive strategies and pollinator attributes exist between meadows and sandy habitats at a microhabitat scale. To test this hypothesis, we conducted a field experiment to investigate variation in floral traits, pollinator attributes, and seed traits in a Tibetan alpine herb (Astragalus purpurinus) across meadow and sandy habitats. Our results show that meadow populations produced fewer nectar-enriched flowers with high sugar concentrations, fewer and larger seeds, and were pollinated primarily by bumble bees. In contrast, sandy-habitat populations produced numerous nectar-poor flowers with low sugar concentrations, more numerous small seeds, and relied on mason bees for pollination. Our results demonstrate that micro-scale habitat heterogeneity drives divergent plant reproductive strategies and pollinator attributes within a single species. These findings reveal novel mechanisms by which small-scale environmental variation shapes reproductive adaptation in alpine ecosystems.

Leaf traits are crucial to seedling growth and survival, and their plasticity can influence seedling fitness in changing environments. Seedlings of Artemisia tridentata, a keystone shrub of the western North American sagebrush steppe, show heteromorphic leaf development. Early leaves are larger and less pubescent than those produced later, suggesting a shift from characteristics favouring rapid growth to those increasing drought tolerance. To investigate this hypothesis, we determined the specific leaf area (SLA) and the osmotic potential at full turgor (π₀) of early and late leaves, and measured their stomatal conductance and photosynthetic rates as leaf water potential (Ψ_l) declined under imposed drought. We also examined whether water stress could trigger late leaf development. At high Ψ_l and per area, early and late leaves had similar photosynthetic rates. However, the SLA of early leaves was three times higher than that of late leaves, yielding higher photosynthetic rates per unit mass in the former. Late leaves had lower π₀ and were less sensitive to drought, exhibiting a lower Ψ_l at 50% of maximum photosynthesis than early leaves. Drought triggered the shedding of early leaves and the initiation of late-like leaves. Formation of these leaves continued upon return to well-watered conditions, possibly indicating stress memory. The overall results suggest that early leaves enhance growth during wet springs following germination, while late leaves prolong photosynthesis as water potentials decline during summer drought. The adaptive value of early leaves may be diminishing due to changing environmental conditions that are accelerating the onset of drought.

Understanding how leaf morphology mediates plant responses to environmental variability is critical for predicting species adaptability under climate change. This study examines whether intraspecific variation in leaf shape among Chenopodium hircinum populations is linked to physiological and functional trait differences and whether such variation reflects adaptive responses to source climate. We cultivated 11 populations of C. hircinum from diverse climatic origins in a common garden experiment. Leaf shape was quantified using descriptors (aspect ratio, circularity, solidity), landmarks, and Elliptical Fourier Descriptors. Physiological traits (stomatal conductance, leaf temperature, chlorophyll content) and functional traits (leaf area, leaf dry weight and leaf mass per area) were measured and analysed in relation to shape and environmental data. Leaf morphology varied significantly among populations and was associated with climatic conditions at origin, especially mean summer temperature. Functional and physiological traits were not directly correlated with environmental variables but showed strong associations with leaf shape. Landmark-based PC2 (lobed vs. rounded forms) and aspect ratio emerged as key predictors of trait variation. Most trait variation occurred at the individual level rather than among populations. Our findings highlight leaf shape as a central mediator linking environmental heterogeneity to physiological function. This suggests that morphology-driven trait integration may enhance adaptability in C. hircinum. Intraspecific diversity in shape and associated traits could serve as a reservoir of resilience under climate change, reinforcing the evolutionary and applied significance of wild relatives in crop improvement.

Climate warming threatens plant sexual reproduction, and plants with extended flowering can experience distinct biotic and abiotic environments across the season. Therefore, responses and adaptations of plant reproduction to warming may vary across the season. Our aim was to examine how climate warming affects plant floral traits and reproductive success across different phenological stages within a single flowering season. In this study, infrared heaters were used to simulate warming (+1.5°C) during the growing season of Impatiens oxyanthera. Flowering was divided into early, middle, and late time-periods based on the flowering onset and end dates of the experimental population. The changes in floral and reproductive characteristics, as well as their relationships across these three time periods, were investigated under warming conditions. Our study on I. oxyanthera demonstrates that warming significantly delayed flowering onset, reduced the number of flowers per plant, and decreased both the length and curvature of nectar spurs. Warming also disrupted correlations between floral traits to some extent compared with the control. Flowers that opened during the late period were smaller, had fewer ovules but more nectar, and produced fewer filled seeds. Warming exerted period-specific impacts on nectar spur length, reducing it during the late flowering period compared with the control treatment but not during the early or middle periods. However, the changes in floral traits caused by the interaction of warming and flowering period did not significantly affect reproductive success at the single-fruit level. These findings highlight the temporal heterogeneity of plant responses to climate warming and suggest that potential buffering mechanisms might contribute to maintaining reproductive outcomes under moderate warming conditions.

Soil nutrient heterogeneity has generally been shown to benefit alien plants more than native ones. However, whether drought, an important aspect of climate change, alters these effects remains an open question. We used a greenhouse experiment with two alien and two native herbaceous plants. Plants were grown either alone or in a mixture (one alien plant and one native plant) in homogeneous and heterogeneous soils, with or without drought. We found that shoot mass of the native plant Alternanthera sessilis and the alien plant Celosia argentea were 27.4% and 76.6% lower in heterogeneous soils than homogenous soils, respectively, indicating a negative effect of soil nutrient heterogeneity. However, these negative effects were eliminated when the plants were grown alone in drought conditions. In contrast, soil nutrient heterogeneity, drought, and competition had little effect on the growth of the native plant Achyranthes bidentata and the alien plant Amaranthus retroflexus. These results suggest that plant species differ in their growth responses to complex environmental changes. These results may have implications for understanding plant invasion outcomes in heterogeneous environments under global climate changes.

Wheat is the most cultivated crop worldwide, and Australia consistently ranks among the top wheat-exporting countries. Although modern technology has expanded the speed and accuracy of conventional breeding, progress is constrained by limited genetic diversity and linkage drag, with new wheat varieties often taking 8-12 years to reach the market. Biotech methods involving the transformation of foreign DNA into genomes [genetic modification (GM)], or editing of native DNA [genome editing (GEd)], provide novel opportunities to efficiently improve traits alongside conventional breeding. In 2020, the world's first GM drought-tolerant bread wheat (HB4) hit the market in Argentina. The USA recently approved HB4 wheat for commercial cultivation, and human consumption of HB4 wheat has been approved by nine countries, including Australia. Currently, 25 countries, Australia included, have deregulated GEd crops in some form, and many other countries have indicated that they will follow suit. As of March 2025, no GM or GEd wheat is commercially grown in Australia. The rate at which private industry integrates GM and GEd into wheat breeding programmes will depend on several factors, including the regulatory consistency governing GM and GEd crops within Australia and among international trading partners, the return on investments relative to deregulation costs including licensing, the level of acceptance amongst growers and consumers, and technical considerations including wheat's amenability to tissue culture. This review contextualizes GM and GEd applications in wheat, often drawing on examples from crop species where biotechnology has been more widely employed, and considers the key stakeholders that will shape the future of GM and GEd wheat in Australia.