Journal of Integrative Plant Biology

Besides playing a crucial role in plant immunity via the nonexpressor of pathogenesis‐related (NPR) proteins, increasing evidence shows that salicylic acid (SA) can also regulate plant root growth. However, the transcriptional regulatory network controlling this SA response in plant roots is still unclear. Here, we found that NPR1 and WRKY45, the central regulators of SA response in rice leaves, control only a reduced sector of the root SA signaling network. We demonstrated that SA attenuates root growth via a novel NPR1/WRKY45‐independent pathway. Furthermore, using regulatory network analysis and mutant characterization, we identified a set of new NPR1/WRKY45‐independent regulators that conservedly modulate the root development and root‐associated microbiota composition in both Oryza sativa (monocot) and Arabidopsis thaliana (dicot) in response to SA. Our results established the SA signaling as a central element regulating plant root functions under ecologically relevant conditions. These results provide new insights to understand how regulatory networks control plant responses to abiotic and biotic stresses.

Glycosylation, a prevalent post‐translational modification in eukaryotic secreted and membrane‐associated proteins, plays a pivotal role in diverse physiological and pathological processes. Although UDP‐N‐acetylglucosamine (UDP‐GlcNAc) is essential for this modification, the specific glycosylation mechanisms during plant leaf senescence and defense responses remain poorly understood. In our research, we identified a novel rice mutant named rbb1 (resistance to blast and bacterial blight1), exhibiting broad‐spectrum disease resistance. This mutant phenotype results from a loss‐of‐function mutation in the gene encoding glucosamine‐6‐phosphate acetyltransferase, an important enzyme in D‐glucosamine 6‐phosphate acetylation. The rbb1 mutant demonstrates enhanced defense responses, evident in increased resistance to rice blast and bacterial blight, along with the upregulation of defense‐response genes. Various biochemical markers indicate an activated defense mechanism in the rbb1 mutant, such as elevated levels of reactive oxygen species and malondialdehyde, reduced enzyme activity and UDP‐GlcNAc content, and decreased expression of N‐glycan and O‐glycan modifying proteins. Moreover, proteome analysis of N‐glycosylation modifications reveals alterations in the N‐glycosylation of several disease‐resistance‐related proteins, with a significant reduction in Prx4 and Prx13 in rbb1‐1. Additionally, the knockout of Prx4 or Prx13 also enhances resistance to Xanthomonas oryzae pv. oryzae (Xoo) and Magnaporthe oryzae (M. oryzae). This study uncovers a novel mechanism of defense response in rice, suggesting potential targets for the development of disease‐resistant varieties.

Phosphorus (P) is an essential macronutrient for plant growth and development. Vacuoles play a crucial role in inorganic phosphate (Pi) storage and remobilization in plants. However, the physiological function of vacuolar phosphate efflux transporters in plant Pi remobilization remains obscure. Here, we identified three ZmVPE genes (ZmVPE1, ZmVPE2a, ZmVPE2b) by combining them with transcriptome and quantitative real‐time polymerase chain reaction (PCR) analyses, showing a relatively higher expression in older leaves than in younger leaves in maize. Moreover, the expression of the ZmVPEs was triggered by Pi deficiency and abscisic acid. ZmVPEs were localized to the vacuolar membrane and responsible for vacuolar Pi efflux. Compared with the wild‐type, Pi remobilization from older to younger leaves was enhanced in ZmVPE‐overexpression lines. zmvpe2a mutants displayed an increase in the total P and Pi concentrations in older leaves, but a decrease in younger leaves. In rice, Pi remobilization was impaired in the osvpe1osvpe2 double mutant and enhanced in OsVPE‐overexpression plants, suggesting conserved functions of VPEs in modulating Pi homeostasis and remobilization in crop plants. Taken together, our findings revealed a novel mechanism underlying Pi remobilization from older to younger leaves mediated by plant vacuolar Pi efflux transporters, facilitating the development of Pi‐efficient crop plants.

Fruit taste quality is greatly influenced by the content of soluble sugars, which are predominantly stored in the vacuolar lumen. However, the accumulation and regulation mechanisms of sugars in most fruits remain unclear. Recently, we established the citrus fruit vacuole proteome and discovered the major transporters localized in the vacuole membrane. Here, we demonstrated that the expression of tonoplast sugar transporter 2 (CsTST2) is closely associated with sugar accumulation during sweet orange (Citrus sinensis) ripening. It was further demonstrated that CsTST2 had the function of transporting hexose and sucrose into the vacuole. Overexpression of CsTST2 resulted in an elevation of sugar content in citrus juice sac, calli, and tomato fruit, whereas the downregulation of its expression led to the reduction in sugar levels. CsTST2 was identified as interacting with CsCIPK23, which binds to the upstream calcium signal sensor protein CsCBL1. The phosphorylation of the three serine residues (Ser277, Ser337, and Ser354) in the loop region of CsTST2 by CsCIPK23 is crucial for maintaining the sugar transport activity of CsTST2. Additionally, the expression of CsCIPK23 is positively correlated with sugar content. Genetic evidence further confirmed that calcium and CsCIPK23‐mediated increase in sugar accumulation depends on CsTST2 and its phosphorylation level. These findings not only unveil the functional mechanism of CsTST2 in sugar accumulation, but also explore a vital calcium signal regulation module of CsCBL1/CIPK23 for citrus sweetness quality.

The recently published study by Liu et al. (2024) on a high quality, chromosome‐level genome of Eleocharis vivipara provides new insight into the multiple evolution of C4 photosynthesis in Cyperaceae and in particular in Eleocharis. The species studied has the rare feature of alternately using C3 photosynthesis underwater and C4 photosynthesis on land (Ueno et al., 1988), making it an exciting model to better understand the genetic control and evolution of the C4 trait and, in particular, the evolutionary challenge to switch from C3 to C4 photosynthesis from the aquatic to the terrestrial environment. This may imply both the control of genes involved in the C4 pathway and deep cellular anatomical changes. Alternately using C3 or C4 photosynthesis may also lead to evolutionary trade‐offs (e.g., optimization of photosynthetic enzymes in contrasting C3 and C4 biochemical contexts). Maintaining C3 and C4 genes may therefore be necessary; hybridization (e.g., allopolyploidization) between non‐C4 and C4 taxa could have been involved to favor the emergence of such facultative photosynthetic strategy...

Polyamines (PAs) are nitrogenous and polycationic compounds containing more than two amine residues. Numerous investigations have demonstrated that cellular PA homeostasis plays a key role in various developmental and physiological processes. The PA balance, which may be affected by many environmental factors, is finely maintained by the pathways of PA biosynthesis and degradation (catabolism). In this review, the advances in PA transport and distribution and their roles in plants were summarized and discussed. In addition, the interplay between PAs and phytohormones, NO, and H2O2 were detailed during plant growth, senescence, fruit repining, as well as response to biotic and abiotic stresses. Moreover, it was elucidated how environmental signals such as light, temperature, and humidity modulate PA accumulation during plant development. Notably, PA has been shown to exert a potential role in shaping the domestication of rice. The present review comprehensively summarizes these latest advances, highlighting the importance of PAs as endogenous signaling molecules in plants, and as well proposes future perspectives on PA research.

One mechanism plants use to tolerate high salinity is the deposition of cutin and suberin to form apoplastic barriers that limit the influx of ions. However, the mechanism underlying barrier formation under salt stress is unclear. Here, we characterized the glycerol‐3‐phosphate acyltransferase (GPAT) family gene TaGPAT6, encoding a protein involved in cutin and suberin biosynthesis for apoplastic barrier formation in wheat (Triticum aestivum). TaGPAT6 has both acyltransferase and phosphatase activities, which are responsible for the synthesis of sn‐2‐monoacylglycerol (sn‐2 MAG), the precursor of cutin and suberin. Overexpressing TaGPAT6 promoted the deposition of cutin and suberin in the seed coat and the outside layers of root tip cells and enhanced salt tolerance by reducing sodium ion accumulation within cells. By contrast, TaGPAT6 knockout mutants showed increased sensitivity to salt stress due to reduced cutin and suberin deposition and enhanced sodium ion accumulation. Yeast‐one‐hybrid and electrophoretic mobility shift assays identified TaABI5 as the upstream regulator of TaGPAT6. TaABI5 knockout mutants showed suppressed expression of TaGPAT6 and decreased barrier formation in the seed coat. These results indicate that TaGPAT6 is involved in cutin and suberin biosynthesis and the resulting formation of an apoplastic barrier that enhances salt tolerance in wheat.

During the move to land, plants acquired transposable elements by horizontal transfer from bacteria and fungi and land plants have many long non‐coding RNAs derived from retrotransposons acquired by horizontal transposon transfer, including some that are highly expressed and involved in the response to drought stress and abscisic acid. image

Plants have mechanisms to transport secondary metabolites from where they are biosynthesized to the sites where they function, or to sites such as the vacuole for detoxification. However, current research has mainly focused on metabolite biosynthesis and regulation, and little is known about their transport. Tanshinone, a class diterpenoid with medicinal properties, is biosynthesized in the periderm of Salvia miltiorrhiza roots. Here, we discovered that tanshinone can be transported out of peridermal cells and secreted into the soil environment and that the ABC transporter SmABCG1 is involved in the efflux of tanshinone ⅡA and tanshinone Ⅰ. The SmABCG1 gene is adjacent to the diterpene biosynthesis gene cluster in the S. miltiorrhiza genome. The temporal–spatial expression pattern of SmABCG1 is consistent with tanshinone accumulation profiles. SmABCG1 is located on the plasma membrane and preferentially accumulates in the peridermal cells of S. miltiorrhiza roots. Heterologous expression in Xenopus laevis oocytes demonstrated that SmABCG1 can export tanshinone ⅡA and tanshinone Ⅰ. CRISPR/Cas9‐mediated mutagenesis of SmABCG1 in S. miltiorrhiza hairy roots resulted in a significant decrease in tanshinone contents in both hairy roots and the culture medium, whereas overexpression of this gene resulted in increased tanshinone contents. CYP76AH3 transcript levels increased in hairy roots overexpressing SmABCG1 and decreased in knockout lines, suggesting that SmABCG1 may affect the expression of CYP76AH3, indirectly regulating tanshinone biosynthesis. Finally, tanshinone ⅡA showed cytotoxicity to Arabidopsis roots. These findings offer new perspectives on plant diterpenoid transport and provide a new genetic tool for metabolic engineering and synthetic biology research.

Replacing the HMA domain of the rice (Oryza sativa) immune receptor RGA5 with that of the rice HMA DOMAIN‐CONTAINING PROTEIN 120 (HMA120) creates a designer RGA5HMA120 that confers resistance to Magnaporthe oryzae isolates expressing the non‐MAX effector gene AVR‐Pita, thus enabling the generation of new synthetic resistance genes. image

Poplar plantations are often established on nitrogen‐poor land, and poplar growth and wood formation are constrained by low nitrogen (LN) availability. However, the molecular mechanisms by which specific genes regulate wood formation in acclimation to LN availability remain unclear. Here, we report a previously unrecognized module, basic region/leucine zipper 55 (PtobZIP55)–PtoMYB170, which regulates the wood formation of Populus tomentosa in acclimation to LN availability. PtobZIP55 was highly expressed in poplar wood and induced by LN. Altered wood anatomical properties and increased lignification were detected in PtobZIP55‐overexpressing poplars, whereas the opposite results were detected in PtobZIP55‐knockout poplars. Molecular and transgenic analyses revealed that PtobZIP55 directly binds to the promoter sequence of PtoMYB170 to activate its transcription. The phenotypes of PtoMYB170 transgenic poplars were similar to those of PtobZIP55 transgenic poplars under LN conditions. Further molecular analyses revealed that PtoMYB170 directly bound the promoter sequences of lignin biosynthetic genes to activate their transcription to increase lignin concentrations in LN‐treated poplar wood. These results suggest that PtobZIP55 activates PtoMYB170 transcription, which in turn positively regulates lignin biosynthetic genes, increasing lignin deposition in the wood of P. tomentosa in the context of acclimation to LN availability.

Cytoplasmic male sterile (CMS) lines play a crucial role in utilization of heterosis in crop plants. However, the mechanism underlying the manipulation of male sterility in cotton by long non‐coding RNA (lncRNA) and brassinosteroids (BRs) remains elusive. Here, using an integrative approach combining lncRNA transcriptomic profiles with virus‐induced gene silencing experiments, we identify a flower bud‐specific lncRNA in the maintainer line 2074B, lncRNA67, negatively modulating with male sterility in upland cotton (Gossypium hirsutum). lncRNA67 positively regulates cytochrome P274B (GhCYP724B), which acted as an eTM (endogenous target mimic) for miR3367. The suppression of GhCYP724B induced symptoms of BR deficiency and male semi‐sterility in upland cotton as well as in tobacco, which resulted from a reduction in the endogenous BR contents. GhCYP724B regulates BRs synthesis by interacting with GhDIM and GhCYP90B, two BRs biosynthesis proteins. Additionally, GhCYP724B suppressed a unique chimeric open reading frame (Aorf27) in 2074A mitochondrial genome. Ectopic expression of Aorf27 in yeast inhibited cellular growth, and over expression of Aorf27 in tobacco showed male sterility. Overall, the results proved that the miR3367–lncRNA67–GhCYP724B module positively regulates male sterility by modulating BRs biosynthesis. The findings uncovered the function of lncRNA67–GhCYP724B in male sterility, providing a new mechanism for understanding male sterility in upland cotton.

Exploring pollen chemical defenses in the economically important plant Camellia oleifera and examining their effects on honeybee flower‐visiting behavior improves the understanding of the ecological functions of pollen and informs efforts to manage honeybees to bolster C. oleifera production. image

Programmed cell death (PCD) is essential for animal and plant development. However, the knowledge of the mechanism regulating PCD in plants remains limited, largely due to technical limitations. Previously, we determined that the protease NtCP14 could trigger PCD in the embryonic suspensor of tobacco (Nicotiana tabacum), providing a unique opportunity to overcome the limitations by creating synchronous two‐celled proembryos with ongoing PCD for transcriptome analysis and regulatory factor screening. Here, we performed comparative transcriptome analysis using isolated two‐celled proembryos and explored the potential regulatory network underlying NtCP14‐triggered PCD. Multiple phytohormones, calcium, microtubule organization, the immunity system, soluble N‐ethylmaleimide‐sensitive factor attachment protein receptor proteins, long non‐coding RNAs and alternative splicing are addressed as critical factors involved in the early stage of suspensor PCD. Genes thought to play crucial roles in suspensor PCD are highlighted. Notably, decreased antioxidant gene expression and increased reactive oxygen species (ROS) levels during suspensor PCD suggest a critical role for ROS signaling in the initiation of NtCP14‐triggered PCD. Furthermore, five genes in the regulatory network are recommended as immediate downstream elements of NtCP14. Together, our analysis outlines an overall molecular network underlying protease‐triggered PCD and provides a reliable database and valuable clues for targeting elements immediately downstream of NtCP14 to overcome technical bottlenecks and gain deep insight into the molecular mechanism regulating plant PCD.

Rapeseed (Brassica napus L.) exhibits high‐sulfur requirements to achieve optimal growth, development, and pathogen resistance. Despite the importance of sulfur, the mechanisms regulating its metabolism and disease resistance are not fully understood. In this study, we found that the zinc finger transcription factors BnaSTOP2s play a pivotal role in sulfur metabolism and Sclerotinia sclerotiorum resistance. Our findings indicate that BnaSTOP2s are involved in sulfur metabolism, as evidenced by extensive protein interaction screening. BnaSTOP2s knockout reduced the content of essential sulfur‐containing metabolites, including glucosinolate and glutathione, which is consistent with the significantly lowered transcriptional levels of BnaMYB28s and BnaGTR2s, key factors involved in glucosinolate synthesis and transportation, respectively. Comprehensive RNA‐seq analysis revealed the substantial effect of BnaSTOP2s on sulfur metabolism from roots to siliques, which serve as pivotal sources and sinks for sulfur metabolism, respectively. Furthermore, we found that leaf lesion size significantly decreased and increased in the BnaSTOP2‐OE and Bnastop2 mutants, respectively, compared with the wild‐type during S. sclerotiorum infection, suggesting a vital role of BnaSTOP2s in plant defense response. In conclusion, BnaSTOP2s act as global regulators of sulfur metabolism and confer resistance to S. sclerotiorum infection in B. napus. Thus, they have potential implications for improving crop resilience.

Fleshy fruits become more susceptible to pathogen infection when they ripen; for example, changes in cell wall properties related to softening make it easier for pathogens to infect fruits. The need for high-quality fruit has driven extensive research on improving pathogen resistance in important fruit crops such as tomato (Solanum lycopersicum). In this review, we summarize current progress in understanding how changes in fruit properties during ripening affect infection by pathogens. These changes affect physical barriers that limit pathogen entry, such as the fruit epidermis and its cuticle, along with other defenses that limit pathogen growth, such as preformed and induced defense compounds. The plant immune system also protects ripening fruit by recognizing pathogens and initiating defense responses involving reactive oxygen species production, mitogen-activated protein kinase signaling cascades, and jasmonic acid, salicylic acid, ethylene, and abscisic acid signaling. These phytohormones regulate an intricate web of transcription factors (TFs) that activate resistance mechanisms, including the expression of pathogenesis-related genes. In tomato, ripening regulators, such as RIPENING INHIBITOR and NON_RIPENING, not only regulate ripening but also influence fruit defenses against pathogens. Moreover, members of the ETHYLENE RESPONSE FACTOR (ERF) family play pivotal and distinct roles in ripening and defense, with different members being regulated by different phytohormones. We also discuss the interaction of ripening-related and defense-related TFs with the Mediator transcription complex. As the ripening processes in climac-teric and non-climacteric fruits share many similarities , these processes have broad applications across fruiting crops. Further research on the individual contributions of ERFs and other TFs will inform efforts to diminish disease susceptibility in ripe fruit, satisfy the growing demand for high-quality fruit and decrease food waste and related economic losses.

Autophagy is a highly conserved cellular program in eukaryotic cells which mediates the degradation of cytoplasmic components through the lysosome, also named the vacuole in plants. However, the molecular mechanisms underlying the fusion of autophagosomes with the vacuole remain unclear. Here, we report the functional characterization of a rice (Oryza sativa) mutant with defects in storage protein transport in endosperm cells and accumulation of numerous autophagosomes in root cells. Cytological and immunocytochemical experiments showed that this mutant exhibits a defect in the fusion between autophagosomes and vacuoles. The mutant harbors a loss‐of‐function mutation in the rice homolog of Arabidopsis thaliana MONENSIN SENSITIVITY1 (MON1). Biochemical and genetic evidence revealed a synergistic interaction between rice MON1 and AUTOPHAGY‐RELATED 8a in maintaining normal growth and development. In addition, the rice mon1 mutant disrupted storage protein sorting to protein storage vacuoles. Furthermore, quantitative proteomics verified that the loss of MON1 function influenced diverse biological pathways including autophagy and vacuolar transport, thus decreasing the transport of autophagic and vacuolar cargoes to vacuoles. Together, our findings establish a molecular link between autophagy and vacuolar protein transport, and offer insights into the dual functions of the MON1–CCZ1 (CAFFEINE ZINC SENSITIVITY1) complex in plants.

Grain size and grain weight are important determinants for grain yield. In this study, we identify a novel OsMAPK5–OsWRKY72 module that negatively regulates grain length and grain weight in rice. We found that loss‐of‐function of OsMAPK5 leads to larger cell size of the rice spikelet hulls and a significant increase in both grain length and grain weight in an indica variety Minghui 86 (MH86). OsMAPK5 interacts with OsMAPKK3/4/5 and OsWRKY72 and phosphorylates OsWRKY72 at T86 and S88. Similar to the osmapk5 MH86 mutants, the oswrky72 knockout MH86 mutants exhibited larger size of spikelet hull cells and increased grain length and grain weight, whereas the OsWRKY72‐overexpression MH86 plants showed opposite phenotypes. OsWRKY72 targets the W‐box motifs in the promoter of OsARF6, an auxin response factor involved in auxin signaling. Dual‐luciferase reporter assays demonstrated that OsWRKY72 activates OsARF6 expression. The activation effect of the phosphorylation‐mimicking OsWRKY72T86D/S88D on OsARF6 expression was significantly enhanced, whereas the effects of the OsWRKY72 phosphorylation‐null mutants were significantly reduced. In addition, auxin levels in young panicles of the osmapk5 and oswrky72 mutants were significantly higher than that in the wild‐type MH86. Collectively, our study uncovered novel connections of the OsMAPKK3/4/5‐OsMAPK5‐mediated MAPK signaling, OsWRKY72‐mediated transcription regulation, and OsARF6‐mediated auxin signaling pathways in regulating grain length and grain weight in an indica‐type rice, providing promising targets for molecular breeding of rice varieties with high yield and quality.

Insects secret chemosensory proteins (CSPs) into plant cells as potential effector proteins during feeding. The molecular mechanisms underlying how CSPs activate plant immunity remain largely unknown. We show that CSPs from six distinct insect orders induce dwarfism when overexpressed in Nicotiana benthamiana. Agrobacterium‐mediated transient expression of Nilaparvata lugens CSP11 (NlCSP11) triggered cell death and plant dwarfism, both of which were dependent on ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1), neuregulin 1 (NRG1) and SENESCENCE‐ASSOCIATED GENE 101 (SAG101), indicating the activation of effector‐triggered immunity (ETI) in N. benthamiana. Overexpression of NlCSP11 led to stronger systemic resistance against Pseudomonas syringae DC3000 lacking effector HopQ1‐1 and tobacco mosaic virus, and induced higher accumulation of salicylic acid (SA) in uninfiltrated leaves compared to another effector XopQ that is recognized by a Toll‐interleukin‐1 receptor (TIR) domain nucleotide‐binding leucine‐rich repeat receptor (TNL) called ROQ1 in N. benthamiana. Consistently, NlCSP11‐induced dwarfism and systemic resistance, but not cell death, were abolished in N. benthamiana transgenic line expressing the SA‐degrading enzyme NahG. Through large‐scale virus‐induced gene silencing screening, we identified a TNL protein that mediates the recognition of CSPs (RCSP), including aphid effector MP10 that triggers resistance against aphids in N. benthamiana. Co‐immunoprecipitation, bimolecular fluorescence complementation and AlphaFold2 prediction unveiled an interaction between NlCSP11 and RCSP. Interestingly, RCSP does not contain the conserved catalytic glutamic acid in the TIR domain, which is required for TNL function. Our findings point to enhanced ETI and systemic resistance by a TNL protein via hyperactivation of the SA pathway. Moreover, RCSP is the first TNL identified to recognize an insect effector.

Plants have evolved a remarkable ability to sense and respond to changes in photoperiod, allowing adjustments to their growth and development based on seasonal and environmental cues. The floral transition is a pivotal stage in plant growth and development, signifying a shift from vegetative to reproductive growth. CONSTANS (CO), a central photoperiodic response factor conserved in various plants, mediates day‐length signals to control the floral transition, although its mechanisms of action vary among plants with different day‐length requirements. In addition, recent studies have uncovered roles for CO in organ development and stress responses. These pleiotropic roles in model plants and crops make CO a potentially fruitful target for molecular breeding aimed at modifying crop agronomic traits. This review systematically traces research on CO, from its discovery and functional studies to the exploration of its regulatory mechanisms and newly discovered functions, providing important insight into the roles of CO and laying a foundation for future research.

The past decade has witnessed rapid developments in gene discovery, biological big data (BBD), artificial intelligence (AI)‐aided technologies, and molecular breeding. These advancements are expected to accelerate crop breeding under the pressure of increasing demands for food. Here, we first summarize current breeding methods and discuss the need for new ways to support breeding efforts. Then, we review how to combine BBD and AI technologies for genetic dissection, exploring functional genes, predicting regulatory elements and functional domains, and phenotypic prediction. Finally, we propose the concept of intelligent precision design breeding (IPDB) driven by AI technology and offer ideas about how to implement IPDB. We hope that IPDB will enhance the predictability, efficiency, and cost of crop breeding compared with current technologies. As an example of IPDB, we explore the possibilities offered by CropGPT, which combines biological techniques, bioinformatics, and breeding art from breeders, and presents an open, shareable, and cooperative breeding system. IPDB provides integrated services and communication platforms for biologists, bioinformatics experts, germplasm resource specialists, breeders, dealers, and farmers, and should be well suited for future breeding.

The fusion of the exonuclease Trex2 with the Cas9 protein significantly enhanced the efficiency of genome editing in hexaploid common wheat, particularly for the simultaneous editing of multiple favorable alleles within a single generation, thereby facilitating genome editing‐assisted breeding in polyploid crops. image

Flowering time is a crucial rice trait that influences its adaptation to various environments, cropping schedules, and agronomic characteristics. Rice breeders have exploited spontaneous mutations in heading date genes to regulate the flowering time. In the present study, we investigated how breeders in Fukui Prefecture regulated days to heading while developing promising rice varieties. Genome‐wide association studies (GWAS) identified Hd1, Hd16, and Hd18 as the major genes controlling days to heading in the population. However, we suspected that this highly bred population might exhibit genomic stratification, which could lead to spurious or false correlations in the GWAS. Thus, we also conducted correlation and partial correlation analyses, which uncovered another key heading date gene, Hd17, that GWAS failed to detect because of its linkage disequilibrium with the major effect gene Hd16. Examination of haplotype frequencies across different breeding periods revealed that the early‐heading Hd16 (Hd16(E)) and late‐heading Hd17 (Hd17(L)) were increasingly co‐selected in the Hd1 functional population. Varieties carrying this Hd16(E)/Hd17(L) combination exhibited days to heading in the range of 70–80, which corresponds to the peak temperature and sunshine period and is also optimal for grain quality and yield components in the Fukui environment. The present study highlights that it is imperative to remain vigilant for Type I (false positives) and Type II (false negatives) errors when performing GWAS on highly bred populations and to implement appropriate countermeasures by accounting for gene‐by‐gene interactions established through the breeding process. We also discuss the effectiveness of Hd16(E), which is not used outside Japan for subtle days to heading control but is widely used in Japan at certain latitudes.

Wild species of domesticated crops provide valuable genetic resources for resistance breeding. Prunus davidiana, a wild relative of peach with high heterozygosity and diverse stress tolerance, exhibits high resistance against aphids. However, the highly heterozygous genome of P. davidiana makes determining the underlying factors influencing resistance traits challenging. Here, we present the 501.7 Mb haplotype‐resolved genome assembly of P. davidiana. Genomic comparisons of the two haplotypes revealed 18,152 structural variations, 2,699 Pda_hap1‐specific and 2,702 Pda_hap2‐specific genes, and 1,118 allele‐specific expressed genes. Genome composition indicated 4.1% of the P. davidiana genome was non‐peach origin, out of which 94.5% was derived from almond. Based on the haplotype genome, the aphid resistance quantitative trait locus (QTL) was mapped at the end of Pda03. From the aphid resistance QTL, PdaWRKY4 was identified as the major dominant gene, with a 9‐bp deletion in its promoter of the resistant phenotype. Specifically, PdaWRKY4 regulates aphid resistance by promoting PdaCYP716A1‐mediated anti‐aphid metabolite betulin biosynthesis. Moreover, we employed a genome design to develop a breeding workflow for rapidly and precisely producing aphid‐resistant peaches. In conclusion, this study identifies a novel aphid resistance gene and provides insights into genome design for the development of resistant fruit cultivars.

Root‐knot nematodes (RKNs; Meloidogyne spp.) are a serious threat to crop production. The competition between plants and pathogens for assimilates influences the outcome of their interactions. However, the mechanisms by which plants and nematodes compete with each other for assimilates have not been elucidated. In this study, we demonstrated that miR396a plays a negative role in defense against RKNs and a positive role in sugar accumulation in tomato roots. The overexpression of SlGRF8 (Solanum lycopersicum growth‐regulating factor 8), the target of miR396a, decreased the sugar content of the roots and the susceptibility to RKNs, whereas the grf8‐cr mutation had the opposite effects. Furthermore, we confirmed that SlGRF8 regulated the sugar content in roots by directly activating the transcription of SlSTP10 (Solanum lycopersicum sugar transporter protein 10) in response to RKN stress. Moreover, SlSTP10 was expressed primarily in the tissues surrounding giant cells, and the SlSTP10 knockout increased both the sugar content in the roots and the plant's susceptibility to RKNs. Overall, this study provides important insight into the molecular mechanism through which the miR396a‐SlGRF8‐SlSTP10 module regulates sugar allocation in roots under RKN stress.