Context: Traditional breeding methods have achieved limited success in improving drought tolerance in rice due to the complex quantitative nature of the trait. However, modern approaches such as marker-assisted breeding (MAB) have enabled the development of drought-resilient varieties. Aim: Given the popularity of ADT (R) 45 and its susceptibility to drought, this study aimed to introgress three drought-yield QTLs qDTY1.1, qDTY3.1, and qDTY12.1 into ADT (R) 45 using marker-assisted backcross breeding, and to identify promising drought-tolerant versions through both genotyping and phenotyping. Methods: Backcrossing was conducted using F1s of ADT (R) 45 crossed with Apo and Way Rarem. Resulting BC3F1 and intermated populations (BC2F1 of ADT (R) 45/Way Rarem // BC2F1 of ADT (R) 45/Apo) were advanced to BC3F2 and intermated F2, followed by BC3F3 and intermated F3 generations. Marker-assisted selection (MAS) was applied in BC3F2 and intermated F2 to identify superior backcross inbred lines (BILs). Key Results: Sixteen BILs showed more than 10 per cent yield gain under both moderate and severe stress. BILs I85 and W61 showed superior physiological traits such as higher relative water content, SPAD value, proline content, and better recovery under drought. Conclusion & Implications: BIL I85 showed best score for leaf rolling, leaf drying, drought recovery as well as higher SPAD value and proline content. While BIL W61 exhibited higher values for SPAD, relative water content, proline content and leaf drying score. These two BILs were also found to possess more than 10 per cent single plant yield over recurrent parent ADT (R) 45. Implications These two BILS are therefore considered for further trials at the national and state levels, and the most promising one will be selected for release as a high-yielding drought-tolerant variety.

Desert ecosystems, which cover more than one-third of Earth's land surface, are experiencing intensifying pressures from land-use disturbances and climate change that threaten their stability and biodiversity. Yet despite their global extent and ecological importance, deserts remain among the least studied biomes, particularly with respect to the belowground processes that sustain productivity, biogeochemical cycling, and long-term ecosystem resilience. Most prior work has focused on vegetation, leaving the roles of soil microbiomes and plant functional trait coordination comparatively underexplored. This knowledge gap is significant because growing evidence shows that microbial dynamics and plant trait syndromes jointly regulate nutrient cycling, carbon stabilization, and drought recovery, potentially determining whether desert ecosystems cross critical thresholds under future climate scenarios. This review synthesizes recent advances in understanding the influence of microbial legacies (persistent effects of past environmental conditions) on ecosystem processes, and how desert plants adapt via coordinated traits that optimize water and nutrient use under extreme conditions. We propose a novel framework that integrates belowground microbial responses and aboveground plant trait strategies, highlighting their interactions and feedback loops in shaping desert ecosystem resilience. By explicitly linking these two domains, the review addresses a major knowledge gap in predicting dryland responses to intensifying climate extremes, offering a mechanistic foundation for improving ecological models and management strategies. This integrated perspective provides new insights into the mechanisms that underlie adaptation to climate stress and offers actionable pathways for conservation, restoration, and climate adaptation in desert landscapes. By bridging microbial ecology and trait-based plant science, this review contributes to a more comprehensive understanding of how desert ecosystems can persist and function in a rapidly changing world.

The limiting factors of tree recovery from drought, particularly the coordination between carbon sources and sinks, remain poorly understood. In this study, juvenile Douglas fir (Pseudotsuga menziesii) were exposed to 28 days of mild or severe drought, followed by 35 days of recovery. We continuously monitored CO₂ and H₂O fluxes in shoots and roots to derive gas exchange and carbon accumulation, while measuring basal area to estimate stem growth and sapwood development. To identify underlying mechanisms of drought recovery, we periodically measured nonstructural carbohydrates (NSC), midday water potential (Ψmd), and foliar abscisic acid (ABA). We found no evidence that ABA or Ψmd limited gas exchange recovery, with stomatal conductance recovery instead related to drought-induced reductions in sapwood development. While carbon accumulation ultimately recovered to control levels following mild stress, severe stress caused persistent impairments, ultimately reducing carbon accumulation by 51%, with stem growth similarly affected. We found no evidence of growth being limited by NSC, which remained abundant. However, we suggest that drought-induced limitations to stem development govern this pattern. This became clear when considering the diurnal growth cycle, where daytime growth was largely absent in trees after exposure to severe drought despite accounting for up to 30% of total growth in control trees. Daytime growth appeared to depend on sufficient sapwood area, which likely buffered xylem tension to support growth conditions. Our findings suggest drought-induced reductions of stem hydraulic development constrain the recovery of gas exchange and growth. Further, altered diurnal growth patterns may explain prolonged productivity declines in forests following drought.

IntroductionEscalating drought in the Lancang River dry–hot valley demands trait-based rules for selecting planting material that can both persist through prolonged water deficits and rebound after rainfall.MethodsWe conducted a controlled drought–rewatering experiment on ten native species (seven shrubs; three herbs) across a graded soil-water regime and quantified twenty-five functional traits spanning morphology, photosynthesis and photochemistry, biochemistry, hydraulics, and nutrient use.ResultsShrubs generally adopted a conservative strategy, exhibiting more negative xylem pressure at 50% loss of conductivity (P50), wider hydraulic safety margins, and faster recovery of PSII efficiency (Fv/Fm) after rewatering; herbs were more acquisitive, with higher specific leaf area and instantaneous water-use efficiency but reduced hydraulic safety. Trait-network analyses revealed hydraulic variables (P50, specific hydraulic conductivity, and turgor loss point) as central nodes tightly covarying with photosynthetic capacity and antioxidative activity, linking plant water status, carbon gain, and stress metabolism. Under severe drought, rising percent loss of conductivity and increased non-photochemical quenching delineated failure domains in which hydraulic disconnection and photoprotective energy dissipation jointly constrained function. Rewatering improved leaf water status and photochemistry but recovery trajectories were species-specific and retained legacy effects consistent with safety–efficiency trade-offs. Multivariate ordination and integrated scoring separated species into tolerant, intermediate, and sensitive types, with the composite ranking highlighting Rumex hastatus, Caryopteris forrestii, and Sophora davidii as priority candidates that couple high hydraulic safety with resilient photosynthetic recovery.Discussion/ConclusionThese findings show that drought performance in this extreme environment emerges from hydraulic–physiological coordination balancing safety, efficiency, and resilience. Practically, they support a minimal diagnostic panel for rapid screening—P50, turgor loss point, hydraulic safety margin, and post-rewatering Fv/Fm recovery—supplemented by acquisitive leaf traits to resolve strategy space, providing transferable criteria for restoration in drylands facing intensifying hydroclimatic variability.

ABSTRACT The Hindu Kush Himalayan (HKH) region, a critical water source for 2 billion people, exhibits contrasting drought patterns under climate change. Using the Self‐Calibrating Palmer Drought Severity Index (scPDSI) and spatiotemporal analyses (1901–2022), we reveal a regional dichotomy: significant drought reduction in Afghanistan, China, and Pakistan (scPDSI slope ≤ +0.016/year, p < 0.05) versus intensifying aridity in Bangladesh, Bhutan, Myanmar, and Nepal (slopes ≥ − 0.015/year, p < 0.05), with India stable (slope = −0.002/year, p > 0.05). Precipitation dominates drought recovery in western HKH (e.g., Pakistan and Afghanistan: r = 0.77), whilst Arctic Oscillation (AO) teleconnections amplify resilience in China ( β = 0.43, p < 0.05). Eastern regions face temperature‐mediated drought intensification (Bangladesh: r = −0.33) and divergent ENSO impacts (Myanmar: r = −0.32). Spatial clustering (Moran's I = 0.753, p < 0.001) confirms drought trends are non‐random, driven by climatic drivers. Mechanistic contrasts emerge: western HKH recovery links to precipitation and snowmelt, whilst eastern regimes integrate AO and Australian Summer Monsoon synergies. Drought relief areas doubled (1.15–2.34 million km 2 , 1901–2022), accelerating post‐1960, contrasting with lowland drought expansion (e.g., Indus Basin). These findings demand spatially targeted adaptation: water‐efficient agriculture in precipitation‐sensitive lowlands and climate‐resilient storage in high‐elevation zones. By bridging hydroclimatic trends with hybrid modelling of threshold‐driven drivers, this study advances transboundary governance frameworks to mitigate the HKH's water insecurity.

Early water-status indicators under combined metal toxicity and drought in tomato leaves.

Drought duration outweighs intensity in governing ecosystem recovery time.

Ecosystem drought recovery and its driving factors in southwest China

Pinus tabulaeformis plantations have higher drought recovery than its natural forests in the warm temperate-subtropical climate transition zone

Ecosystem drought recovery and influencing factors in temperate China and the Qinghai-Tibet alpine region

ABSTRACT Drought significantly affects agriculture and ecology in the Horn of Africa (HOA), whereby livelihoods largely depend on rainfed farming. This study aims to analyze drought propagation and its impacts on vegetation and crop productivity, with a specific focus on recovery dynamics. Over the period 2000–2022, we developed and integrated a suite of physically based remote sensing indices, including the Drought Propagation Index (DPI), Crop Stress Index (CSI), Soil Moisture Deficit (SMD), Water Deficit Index (WDI), and Drought Recovery and Rate Index (DRRI), into a novel framework. The performance of this integrated framework was further evaluated against the conventional Standardised Precipitation Index (SPI) to validate its ability for capturing drought propagation and agricultural impacts. The findings identify the eastern and southeastern HOA as major drought hotspots, experiencing severe droughts 70%–100% of the time and exhibiting worsening temporal trends. SPI was strongly correlated with DPI ( r = 0.67, p < 0.05), thus proving to be reliable. Vegetation indices showed significant reductions during droughts, while DPI positively correlated with NDVI at 0.56 and EVI at 0.54. Crop production was reduced by 30%–35% in Somalia, especially for maize and sorghum, whereas Ethiopia showed more resistance because of irrigation. The mean recovery time exceeded 2 months during the 2010 and 2016 droughts in southeastern HOA, indicating low resilience, whereas northern areas recovered faster. This framework offers practical recommendations for drought mitigation, drought‐resistant crops, and adaptive resource management to deal with vulnerabilities.

Determinants of flash drought recovery rates: the role of precipitation patterns and surface heterogeneity

In Uganda, rain-fed crops frequently encounter cycles of drought stress followed by rewatering. Thus, with escalating fluctuations in water supply, drought recovery has become a critical focus for future sorghum drought phenotyping, genetics, and breeding research. However, there is currently a low knowledge of the drought recovery potential of prospective genotypes in Uganda’s National Sorghum Improvement Program. The present study aimed to assess the response of selected genotypes to rewatering after drought. Sixteen sorghum genotypes and two check varieties were evaluated under two contrasting moisture regimes: well-watered and drought stress-rewatering in a split-plot layout using a randomized complete block design (RCBD). Watering regimes were assigned to whole plots, while sorghum genotypes were assigned to subplots, with three replications. The results showed highly significant effects (p < 0.05) of drought stress on key agronomic traits, decreased dry weight, grain weight, and biomass yield by 39%, 43% and 37%, respectively, and delayed flowering by an average of 11 days. Key genotype-specific traits associated with drought recovery included rapid rehydration, compensatory growth, and maintenance of high relative chlorophyll content, all of which were essential for optimizing yields after stress. Leveraging drought tolerance indices, genotypes were ranked by their recovery potential and further classified into four distinct groups (A–D) based on their yield performance and stability under the two watering regimes. Genotypes in category A demonstrated high yield stability and strong recovery potential. Conversely, genotypes in category D exhibited the poorest recovery response. Overall, the information generated from this study will support future sorghum breeding efforts for drought resilience.

Over four decades (1984-2024), Naâma's arid ecosystems exhibited alarming environmental degradation, with climate trends showing a significant SPEI decline (-0.4 annually, p<0.001), indicating intensified drought, while land surface temperature surged by +3.5 °C (+0.085°C/year, p<0.001) 2.1 times faster than global warming rates. The Aridity Index rose (+0.0003/year, p = 0.002), confirming accelerated aridification, with a critical tipping point detected in 2000. Vegetation dynamics mirrored this crisis: NDVI declined significantly across all municipalities (-0.002/year, p<0.001), most severely in Asla (-0.0030/year) and Djenien Bourezg (-0.0028/year), while NDVI-based water stress (NDWI) also dropped (-0.0004/year, p<0.05). Only soil-adjusted SAVI showed relative stability, suggesting limited soil adaptation. Ecological resilience varied starkly among municipalities, with Kasdir and Mekmen Ben Amar demonstrating higher resistance (R = 0.15-0.18) and shorter drought recovery (1.5 years), contrasting with Asla and Djenien Bourezg’s vulnerability (R = 0.06-0.07) and prolonged recovery (3.8 years). The Synthetic Environmental Index (SEI) quantified this hierarchy: Asla and Djenien Bourezg faced critical degradation (SEI<-1.2), driven by thermal stress (LST weight: 0.28) and aridity (AI weight: 0.22), while Kasdir and Mekmen Ben Amar maintained moderate conditions (SEI>-0.5). All municipalities except Mekmen Ben Amar showed significant SEI declines, with Naâma’s degradation rate 2.3 times faster than the Mediterranean Basin, underscoring the urgent need for targeted restoration within Algeria’s Green Dam initiative.

Abstract Extreme droughts alter vegetation dynamics worldwide and the effects often persist after the drought ended. Indirect drought effects mediated by the soil microbial community can continue to affect plant growth during drought recovery and may impact plant–soil feedback (PSF), the effect a species has on its own growth via its rhizosphere microbiome. Changes in plant inputs to the soil, such as root exudates and litter, may drive these drought legacy effects through changes in soil bacterial and fungal communities. In a three‐stage greenhouse experiment, we assessed drought legacy effects on plant biomass and PSF of three common grassland species. In a first conditioning phase, soil was conditioned directly by plants under drought and ambient conditions. In a second conditioning phase, soil was conditioned by the addition of either conditioned soil inoculum or root exudates or root litter produced in the first phase by droughted or non‐droughted plants. In the feedback phase, a new set of plants was grown in soil conditioned by the same species compared to soil conditioned by another species across all soil conditioning types and their biomass linked to soil microbial community data. We found that only soil conditioning with plants, but not inoculum, exudates or litter, resulted in a consistent negative drought legacy effect on plant growth, which was linked to lower microbial biomass and shifts in bacterial and fungal community composition. We could identify a set of fungal and bacterial taxa which were differentially abundant in drought and well‐watered soil and accurately predicted plant growth. PSF in plant‐conditioned soil differed between species, but was only affected by drought in Rumex acetosa . This pattern was not reproduced through the addition of inoculum, root exudates or root litter. Synthesis . Our results show that drought indirectly restricts plant growth, which is not mediated by root exudates or root litter, but through altering microbial biomass and community composition. These findings suggest that plant recovery from extreme drought is obstructed by persistent changes in soil microbial communities.

Heritable variation in root emergence during post-drought recovery reveals potential links to seedling drought recovery in rice

All organisms experience stress as an inevitable part of life, from single-celled microorganisms to complex multicellular beings. The ability to recover from stress is a fundamental trait that determines the overall resilience of an organism, yet stress recovery is understudied. To investigate how plants recover from drought, we examine a fine-scale time series of RNA sequencing starting 15 min after rehydration following moderate drought. We reveal that drought recovery is a rapid process involving the activation of thousands of recovery-specific genes. To capture these rapid recovery responses in different Arabidopsis thaliana (A. thaliana) leaf cell types, we perform a single-nucleus transcriptome analysis at the onset of drought recovery, identifying a cell type-specific transcriptional state developing independently across cell types. To further validate the cell-type specific transcriptional changes observed during drought recovery, we employ spatial transcriptomics using multiplexed error-robust fluorescence in situ hybridization (MERFISH), revealing anatomical localization of recovery-induced gene expression programs across Arabidopsis leaf tissues. Furthermore, we reveal a recovery-induced activation of the immune system that occurs autonomously, and which enhances pathogen resistance in vivo in A. thaliana, wild tomato (Solanum pennellii) and domesticated tomato (Solanum lycopersicum cv. M82). Since rehydration promotes microbial proliferation and thereby increases the risk of infection, the activation of drought recovery-induced immunity may be crucial for plant survival in natural environments. These findings indicate that drought recovery coincides with a preventive defense response, unraveling the complex regulatory mechanisms that facilitate stress recovery in different plant cell types.

Woody plants with green stems may have advantages over non-green-stemmed plants in that extra photosynthetic carbon gain has the potential to improve plant drought tolerance and aid drought recovery. However, most studies relating to green stem photosynthesis and drought tolerance have been conducted on non-horticultural plants under natural growing conditions. We investigated whether avocado green stem photosynthesis enhances drought tolerance and recovery. We applied light exclusion and drought treatments to 3-year-old potted trees of cultivars ‘Hass’ and ‘Fuerte’. Measurements of soil moisture, midday stem water potential, stem photosynthesis, bark chlorophyll concentration, concentration of sugars + starch and stem hydraulic conductivity were conducted before, during, and 3 weeks after rewatering. Green stems of avocado re-assimilate CO2, but values did not significantly differ between cultivars. We also found that light exclusion reduced stem photosynthesis by 65% in ‘Fuerte’ and 30% in ‘Hass’ although bark chlorophyll concentration was unchanged. Drought reduced stem photosynthesis by 60%. Following drought recovery, there were neither treatment nor cultivar effects on stem photosynthesis. We also observed no effect of light treatment on hydraulic conductivity, such that there is no clear effect of stem photosynthesis on drought tolerance of these avocado trees. However, we observed an increase in hydraulic conductivity during the drought period with an increase in the concentration of sugars in the sapwood and a decrease in the concentration of starch, suggesting osmotic adjustment. Nonetheless, the contribution of carbon gain through stem photosynthesis may not play a significant role in hydraulic functioning of avocado under these conditions.

Background and AimsNatural rainfed conditions present drought episodes interspersed with periods of moderate to high soil moisture levels. This study investigates the genetic variation in root-to-shoot growth in response to a wet–drought–wet cycle and aims to identify rice (Oryza sativa) lines differing in drought recovery, focusing on detailed root trait investigations.MethodsIn total, 100 different rice accessions were screened under fluctuating moisture across three field seasons for GWAS (genome-wide association study) analysis. In a subset of 20 genotypes, crown root number and leaf length were recorded regularly to calculate a water recovery index (WRI). Two lines contrasting in WRI were grown in a glasshouse experiment to resolve detailed root phenotypes in simulated field drought and re-watering.Key ResultsGWAS co-locations indicated drought recovery-associated loci that included candidate genes previously reported for several abiotic stressors. In the subset of 20 genotypes, crown root growth was impacted most by the transition from drought to re-watering. The calculated WRI distinguishes different responses to drought and re-watering. A glasshouse study reproduced the contrasting growth of two selected lines, with ‘ADT 12’ shoot and root growth being strongly impaired by drought, while ‘ARC 18202’ growth was not suppressed. Drought caused a significant decrease in S-type lateral root production in both lines, while a significant increase in L-type lateral root proportion was only found for ‘ADT 12’. These phenotypes were reversed 7 d after re-watering to values of the well-watered control plants.ConclusionsOverall, in-depth root phenotyping confirmed the drought-resistance and recovery ability of ‘ARC 18202’ in the field and highlighted the importance of S-type and L-type lateral root formation already under well-watered conditions prior to drought. ‘ARC 18202’ had a higher amount of thick lateral roots before drought and, therefore, less change in lateral root formation under drought and re-watering conditions.

Severe droughts affect vegetation through several processes, such as hydraulic failure, early leaf senescence, depletion of carbon reserves, and reduced growth. These, in turn, can delay drought recovery and influence ecosystem functioning beyond the drought duration. The goal of this study is to investigate the direct response and physiological recovery of a Mediterranean oak (Quercus ilex L.) forest in southern France following the 2017 drought. We analysed eddy covariance-based observations of gross primary productivity (GPP), evapotranspiration (ET) and tree sap flow measurements. To study drought recovery, we used a random forest regression model to predict vegetation functioning in the post-drought years based on hydro-meteorological conditions. Potential legacy effects can be indicated by the difference between predicted and actual values. The 2017 drought peaked in autumn, with the lowest soil moisture of the study period 2000-2021. Concurrently, we detected the lowest GPP, ET, and sap flow for this time of the year on record. Despite severe reductions in vegetation functioning during drought, we found no legacy effects on GPP, ET, and sap flow. This suggests that the physiological functioning of Q. ilex woodlands recovers rapidly and completely. We hypothesize that this fast recovery is supported by favourable pre- and post-drought hydro-meteorological conditions, as spring 2017 was unusually sunny but not water-limited, and 2018 was the wettest year in the studied record. High drought resilience of Q. ilex forests is important in the context of anticipated increase in drought frequency and intensity under climate change. However, it remains yet to be determined to what extent the drought resilience can be sustained during potentially recurrent droughts in the future.