Auxin Regulation Research Articles

NtLPA1 overexpression regulates the growth of tobacco and enhances resistance to blight.

The involvement of Loose Plant Architecture 1 (LPA1) in regulating plant growth and leaf angle has been previously demonstrated. However, the fundamental genetic background remains unidentified. To further understand the tissue expression profile of the NtLPA1 gene, an overexpression vector (pBI121-NtLPA1) was developed and employed to modify tobacco using the leaf disc method genetically. Validation confirmed the generation of transgenic tobacco plants with NtLPA1 overexpression. The findings indicated that increased NtLPA1 overexpression substantially decreased plant auxin sensitivity and modulated signal transduction and polar transport, significantly reducing leaf angle, diminished leaf area during early and late growth stages, and shortened root length. In summary, NtLPA1 augmented tobacco resistance to severe shin disease by modulating the expression of disease-associated genes PBZ1, PR1b, and the growth regulator auxin polar transport factor PIN1.

Transcriptome and miRNA Reveal the Key Factor Regulating the Somatic Embryogenesis of Camellia oleifera

The key genes involved in plant regeneration play a crucial role in enhancing reproductive capabilities, plant genetic transformation, and gene editing efficiency. Camellia oleifera, a vital woody oil crop, faces challenges in genetic improvement efficiency due to its slow growth and the difficulties it experiences during the regeneration process. This study focused on the expression levels of mRNA and miRNA during the somatic embryogenesis of C. oleifera, and the core genes of plant regeneration involved in the C. oleifera somatic embryogenesis process were identified, including WUSCHEL-related homeobox 4 (WOX4), WOX13, and DNA-Binding One Zinc Finger 5.6 (DOF5.6) during the somatic embryo callus induction phase; WOX11, PLETHORA2 (PLT2), and Growth-regulating factor (GRF) during the somatic embryogenesis and bud regeneration phase; and miRNAs such as miR156, miR319, and miR394. These key regulatory factors may participate in the regulation of plant auxin and cytokinin and play a core role in the regeneration process of C. oleifera. The research data elucidate the process of somatic embryogenesis in C. oleifera at the molecular level. The key regulatory genes identified provide potential targets for improving the regeneration efficiency of C. oleifera and other woody oilseed plants.

Sly-miR398b Mediates Mature Leaf Flattening by Orchestrating Auxin and H2O2 Signalling in Tomato.

Leaf flattening plays a pivotal role in optimizing light capture and enhancing photosynthesis efficiency. While extensive research has clarified the molecular mechanisms governing the initial stages of leaf flattening, understanding the maintenance of this process in mature leaves remains limited. Our investigation focused on sly-miR398b in tomatoes and revealed its crucial role in maintaining leaf flattening. In situ hybridization experiments indicated predominant expression of sly-miR398b in the abaxial side. Disrupting sly-miR398b using CRISPR/Cas9 relieved its suppression on target gene (Cu/Zn-SOD, SlCSD1), elevating SlCSD1 levels specifically on the abaxial side. Consequently, this asymmetrical expression of SlCSD1 increased hydrogen peroxide (H2O2) levels in the abaxial side, hindering auxin influx genes while promoting auxin efflux gene expression. This shift reduced auxin response gene expression in the abaxial side of mature leaves compared to the adaxial side, leading to leaf epinasty in sly-miR398b mutants. Exogenous H2O2 spraying induced leaf epinasty, downregulating SlGH3.5 and upregulating SlPIN3 and SlPIN4. Remarkably, spraying with 1-naphthalacetic acid (NAA) restored leaf flattening in sly-miR398b mutants. Our findings offer novel insights into mature leaf flattening maintenance via sly-miR398b's regulation of auxin and H2O2 signalling pathways.

Transcriptome analysis of maize resistance to Fusarium verticillioides

ABSTRACT Maize (Zea mays) is a crucial crop for both food and economic purposes. Fusarium verticillioides is known to cause ear rot in corn, leading to a reduction in corn yield. Understanding the regulatory network of maize resistance to this ear rot is crucial for identifying key genes associated with disease resistance. The study revealed that inbred line J1259 exhibited resistance to Fusarium verticillioides by increasing the activities of POD and CAT enzymes. Transcriptome analysis at 48 and 96 hours post-infection with Fusarium verticillioides revealed a large number of DEGs involved in plant-pathogen interactions, MAPK signaling pathways-plants and plant hormone signaling were significant up-regulated. Additionally, transcription factors related to hormone signaling, particularly the ARF family involved in auxin regulation, were enriched. These results lay a foundation for further investigations into the mechanisms underlying the disease resistance response of J1259.

Transcriptome Reveals the Regulation of Exogenous Auxin Inducing Rooting of Non-Rooting Callus of Tea Cuttings.

Cuttage is the main propagation method of tea plant cultivars in China. However, some tea softwood cuttings just form an expanded and loose callus at the base, without adventitious root (AR) formation during the propagation period. Meanwhile, exogenous auxin could promote the AR formation of tea plant cuttings, but the regulation mechanism has not yet explained clearly. We conducted this study to elucidate the regulatory mechanism of exogenous auxin-induced adventitious root (AR) formation of such cuttings. The transcriptional expression profile of non-rooting tea calluses in response to exogenous IBA and NAA was analyzed using ONT RNA Seq technology. In total, 56,178 differentially expressed genes (DEGs) were detected, and most of genes were significantly differentially expressed after 12 h of exogenous auxin treatment. Among these DEGs, we further identified 80 DEGs involved in the auxin induction pathway and AR formation. Specifically, 14 auxin respective genes (ARFs, GH3s, and AUX/IAAs), 3 auxin transporters (AUX22), 19 auxin synthesis- and homeostasis-related genes (cytochrome P450 (CYP450) and calmodulin-like protein (CML) genes), and 44 transcription factors (LOB domain-containing protein (LBDs), SCARECROW-LIKE (SCL), zinc finger protein, WRKY, MYB, and NAC) were identified from these DEGs. Moreover, we found most of these DEGs were highly up-regulated at some stage before AR formation, suggesting that they may play a potential role in the AR formation of tea plant cuttings. In summary, this study will provide a theoretical foundation to deepen our understanding of the molecular mechanism of AR formation in tea cuttings induced by auxin during propagation time.

Structure and dynamics of microbial communities associated with the resurrection plant Boea hygrometrica in response to drought stress.

The resurrection plant Boea hygrometrica selectively recruits and assembles drought-specific microbial communities across the plant-soil compartments, which may benefit plant growth and fitness under extreme drought conditions. Plant-associated microbes are essential for facilitating plant growth and fitness under drought stress. The resurrection plant Boea hygrometrica in natural habitats with seasonal rainfall can survive rapid desiccation, yet their interaction with microbiomes under drought conditions remains unexplored. This study examined the bacterial and fungal microbiome structure and drought response across plant-soil compartments of B. hygrometrica by high-throughput amplicon sequencing of 16S rRNA gene and internal transcribed spacer. Our results demonstrated that the diversity, composition, and functional profile of the microbial community varied considerably across the plant-soil compartments and were strongly affected by drought stress. Bacterial and fungal diversity was significantly reduced from soil to endosphere and belowground to aboveground compartments. The compartment-specific enrichment of the dominant bacteria phylum Cyanobacteriota and genus Methylorubrum in leaf endosphere, genera Pseudonocardia in rhizosphere soil and Actinoplanes in root endosphere, and fungal phylum Ascomycota in the aboveground compartments and genera Knufia in root endosphere and Cladosporium in leaf endosphere composed part of the core microbiota with corresponding enrichment of beneficial functions for plant growth and fitness. Moreover, the recruitment of dominant microbial genera Sphingosinicella and Plectosphaerella, Ceratobasidiaceae mycorrhizal fungi, and numerous plant growth-promoting bacteria involving nutrient supply and auxin regulation was observed in desiccated B. hygrometrica plants. Our results suggest that the stable assembled drought-specific microbial community of B. hygrometrica may contribute to plant survival under extreme environments and provide valuable microbial resources for the microbe-mediated drought tolerance enhancement in crops.

Proteomic investigation reveals molecular mechanisms of plant height regulation in foxtail millet

Plant height is an essential characteristic of agronomic traits, and an ideal plant height is essential for high crop yield. Foxtail millet (Setaria italica) has been regarded as a novel diploid C4 model crop. The proteomic profiles of the internode, node, and leaf in two foxtail millet varieties with different heights, Ci846 and Yugu 18, were investigated at the jointing stage in our study. There were different degrees of the enrichment processes such as plant hormone signal transduction, the MAPK signaling pathway, and so on. In particular, the proper content of auxin could activate downstream SiARFs-SiSAURs expression, which enhances the length of internodes. Haplotype analysis of SiSAUR-like revealed two differential haplotypes of associated plant height, Hap1 and Hap2. The molecular marker SiSAUR-like-FCM1-2 can effectively separate Hap1 and Hap2 in different materials. Two additional genes, designated SiGH3 and SiTCH4, were found to be associated with plant height regulation. In conclusion, this study not only uncovers the crucial role of auxin regulators in modulating plant height during the jointing stage, but also provides molecular markers that are invaluable for molecular breeding efforts. The findings of this research help to elucidate the molecular mechanisms of plant height determination and preparation for crop variety innovation and breeding.

EFEKTIVITAS AUKSIN DAN GIBERELIN TERHADAP UMUR BERBUNGA DAN PANEN TANAMAN KORO PEDANG (Cannavalia ensiformis)

The aim of this research was to determine the effect of the growth regulator substances auxin and gibberellin as chemical mutagens on flowering time and harvest time of jack bean. This research was carried out in the Greenhouse of the Faculty of Agriculture, Bachelorwiyata Tamansiswa University, Yogyakarta City. This research was carried out from August to December 2023. The research was carried out using the Completely Randomized Design (CRD) method. Consisting of 4 replications, each replication contained 3 treatments. So 12 experimental units were obtained, namely: P1 = IAA 2 ppm + GA 10 ppm, P2 = IAA 4 ppm + GA 10 ppm, P3 = IAA 6 ppm + GA 10 ppm. The collected data was analyzed using 5% ANOVA and further tested using 5% Duncan Multiple Range Test (DMRT). The influence of the growth regulators auxin and gibberellin as chemical mutagens showed varying results at concentrations of IAA 4 ppm and GA 10 ppm which affected the day of harvest. However, there was no difference in flowering age between all treatments.

Plant Growth Regulators (PGRs) Study for Root and Bud Induction on Stem Cuttings of <i>Stevia rebaudiana</i>

The Stevia plant is used as a low calorie natural sweetener known as"the sweet herb of Paraguay". Stevia leaves a higher level of sweetness than cane sugar. Stevia can be propagated by stem cutting techniques. Soaked of stem cuttings in Plant Growth Regulators (PGRs) auxin can promote the growth and development of Stevia. Research was conducted to determine the effect of commercial PGRs (Rootone-f) and natural PGRs from Shallot extract. This study used a complete randomized design with different concentrations, both Rootone-f (0, 100, 200, 300, 400 and 500 mg/L) and shallot extract (0, 0.5%, 1%, 1.5% and 2%). Observations were made after 6 weeks (42 days) of planting on several growth parameters (height of plant, number or buds, number of leaves, number of roots and length of roots). Commercial PGRs showed a significant effect on growth parameters. While natural PGRs of shallot showed a significant effect on height of growth parameters. The recommended concentration of commercial PGRs for Stevia rebaudiana Bertoni M. stem cuttings was 300 mg/L.

Metabolomics reveals how ethylene‐auxin interaction delays tomato ripening maintaining fruit nutritional and sensorial quality

SummaryThe antagonistic roles of ethylene and auxin are well established, although the exact role of auxin in ripening regulation remains unclear. A metabolomic approach can be a strategy to understand the role of this phytohormone in improving tomato quality. This study used metabolomic approaches to investigate how the interaction between ethylene and auxin affects tomato fruit nutritional and sensorial quality, with a particular emphasis on aroma metabolites. Tomato (Solanum lycopersicum cv. Micro‐Tom) fruits were randomly grouped according to treatment with ethylene (ETHY), auxin (IAA), or both (ETHY + IAA) phytohormones. Fruits without treatment were grouped in CTRL. Ethylene and auxin treatments affected carbohydrates (fructose, sucrose, and glucose), organic acids (citric and malic acids), and amino acids (valine, asparagine, and GABA), with the main volatile organic compounds precursors positively impacting ETHY + IAA aroma compounds. In conclusion, the comparison of metabolome profiles suggests that auxin regulation may overlap the ethylene regulatory system. Furthermore, tomato fruits treated with both phytohormones maintained metabolic profiles similar to those of untreated fruits in delayed ripening conditions, besides the improved tomato aroma.

Optimizing callus formation in the endangered medicinal tree Hydnocarpus macrocarpa using phytohormone

Hydnocarpus macrocarpa (Flacourtiaceae) is one of the endemic and endangered medicinal tree, was selected to investigate the influence of plant growth regulators on callus formation. H. macrocarpa is majorly distributed at low and medium elevations of the Southern Western Ghats. The seeds of this plant are used for the treatment of ulcers, biliousness, leprosy and epilepsy. An experiment was carried out with two different methods. In the first method Murashige and Skoog (MS) medium supplemented with cytokinin alone or combined with auxin (2–4-Dichlorophenoxy acetic acid; Naphthalene acetic acid; Indole acetic acid; Indole butyric acid and Gibberellic acid) at different concentrations (1, 2, 3, 4 and 5 µM) were used; in the seond method, MS medium supplemented with coconut endosperm (Solid and liquid) extract (1, 2, 3, 4 and 5 %) with Aloe vera jelly extract at different concentrations (1, 2, 3, 4 and 5 %) in combination and separately were used. Among the different treatments, good callus proliferation was obtained using MS medium supplemented with Benzylaminopurine and in combination with Naphthalene acetic acid and 2–4-Dichlorophenoxyacetic acid (3 µM and 4 µM). But the best callus proliferation, shoot tip proliferation; auxiliary root and shoot formation were observed in MS medium supplemented with Aloe vera jelly extract in combination with coconut endosperm extract. The natural growth regulators supplemented with the media gave a positive response for plant growth. The results showed that the natural growth regulators, such as coconut endosperm and Aloe vera jelly extracts were found to be more efficient than the synthetic growth regulators (auxin and cytokinin). The presence of Indole acetic acid and Indole butyric acid in both Aloe vera jelly extracts and coconut endosperm were confirmed by High performance liquid chromatography and Fourier transform infrared spectroscopy analysis.

Transcriptome Sequencing Reveals the Mechanism of Auxin Regulation during Root Expansion in Carrot.

Carrot is an important vegetable with roots as the edible organ. A complex regulatory network controls root growth, in which auxin is one of the key players. To clarify the molecular mechanism on auxin regulating carrot root expansion, the growth process and the indole-3-acetic acid (IAA) content in the roots were measured in this experiment. It was found that the rapid expansion period of the root was from 34 to 41 days after sowing and the IAA content was the highest during this period. The root growth then slowed down and the IAA levels decreased. Using the transcriptome sequencing database, we analyzed the expression of IAA-metabolism-related genes and found that the expression of most of the IAA synthesis genes, catabolism genes, and genes related to signal transduction was consistent with the changes in IAA content during root expansion. Among them, a total of 31 differentially expressed genes (DEGs) were identified, including 10 IAA synthesis genes, 8 degradation genes, and 13 genes related to signal transduction. Analysis of the correlations between the DEGs and IAA levels showed that the following genes were closely related to root development: three synthesis genes, YUCCA10 (DCAR_012429), TAR2 (DCAR_026162), and AMI1 (DCAR_003244); two degradation genes, LPD1 (DCAR_023341) and AACT1 (DCAR_010070); and five genes related to signal transduction, IAA22 (DCAR_012516), IAA13 (DCAR_012591), IAA27 (DCAR_023070), IAA14 (DCAR_027269), and IAA7 (DCAR_030713). These results provide a reference for future studies on the mechanism of root expansion in carrots.

Light-sensitive short hypocotyl genes confer symbiotic nodule identity in the legume Medicago truncatula

Legumes produce specialized root nodules that are distinct from lateral roots in morphology and function, with nodules intracellularly hosting nitrogen-fixing bacteria. We have previously shown that a lateral root program underpins nodule initiation, but there must be additional developmental regulators that confer nodule identity. Here, we show two members of the LIGHT-SENSITIVE SHORT HYPOCOTYL (LSH) transcription factor family, predominantly known to define shoot meristem complexity and organ boundaries, function as regulators of nodule organ identity. In parallel to the root initiation program, LSH1/LSH2 recruit a program into the root cortex that mediates the divergence into nodules, in particular with cell divisions in the mid-cortex. This includes regulation of auxin and cytokinin, promotion of NODULE ROOT1/2 and Nuclear Factor YA1, and suppression of the lateral root program. A principal outcome of LSH1/LSH2 function is the production of cells able to accommodate nitrogen-fixing bacteria, a key feature unique to nodules.

The potential of plant growth regulator (auxin) in enhancing fruit crop propagation via Stem Cuttings

The potential of plant growth regulator (auxin) in enhancing fruit crop propagation via Stem Cuttings

Chloroplast Auxin Efflux Mediated by ABCB28 and ABCB29 Fine-Tunes Salt and Drought Stress Responses in Arabidopsis.

Photosynthesis is among the first processes negatively affected by environmental cues and its performance directly determines plant cell fitness and ultimately crop yield. Primarily sites of photosynthesis, chloroplasts are unique sites also for the biosynthesis of precursors of the growth regulator auxin and for sensing environmental stress, but their role in intracellular auxin homeostasis, vital for plant growth and survival in changing environments, remains poorly understood. Here, we identified two ATP-binding cassette (ABC) subfamily B transporters, ABCB28 and ABCB29, which export auxin across the chloroplast envelope to the cytosol in a concerted action in vivo. Moreover, we provide evidence for an auxin biosynthesis pathway in Arabidopsis thaliana chloroplasts. The overexpression of ABCB28 and ABCB29 influenced stomatal regulation and resulted in significantly improved water use efficiency and survival rates during salt and drought stresses. Our results suggest that chloroplast auxin production and transport contribute to stomata regulation for conserving water upon salt stress. ABCB28 and ABCB29 integrate photosynthesis and auxin signals and as such hold great potential to improve the adaptation potential of crops to environmental cues.

The transcription factor MdBPC2 alters apple growth and promotes dwarfing by regulating auxin biosynthesis.

Auxin plays important roles throughout plant growth and development. However, the mechanisms of auxin regulation of plant structure are poorly understood. In this study, we identified a transcription factor (TF) of the BARLEY B RECOMBINANT/BASIC PENTACYSTEINE (BBR/BPC) family in apple (Malus × domestica), MdBPC2. It was highly expressed in dwarfing rootstocks, and it negatively regulated auxin biosynthesis. Overexpression of MdBPC2 in apple decreased plant height, altered leaf morphology, and inhibited root system development. These phenotypes were due to reduced auxin levels and were restored reversed after exogenous indole acetic acid (IAA) treatment. Silencing of MdBPC2 alone had no obvious phenotypic effect, while silencing both Class I and Class II BPCs in apple significantly increased auxin content in plants. Biochemical analysis demonstrated that MdBPC2 directly bound to the GAGA-rich element in the promoters of the auxin synthesis genes MdYUC2a and MdYUC6b, inhibiting their transcription and reducing auxin accumulation in MdBPC2 overexpression lines. Further studies established that MdBPC2 interacted with the polycomb group (PcG) protein LIKE HETEROCHROMATIN PROTEIN 1 (LHP1) to inhibit MdYUC2a and MdYUC6b expression via methylation of histone 3 lysine 27 (H3K27me3). Silencing MdLHP1 reversed the negative effect of MdBPC2 on auxin accumulation. Our results reveal a dwarfing mechanism in perennial woody plants involving control of auxin biosynthesis by a BPC transcription factor, suggesting its use for genetic improvement of apple rootstock.

Mechanistic insights into auxin-enhancing polycyclic aromatic hydrocarbon uptake by wheat roots: Evidence from in situ intracellular pH and root-surface H+ flux

Polycyclic aromatic hydrocarbons (PAHs) are a group of extremely carcinogenic organic pollutants. Our previous findings have demonstrated that plant roots actively take up PAHs through co-transport with H+ ions. Auxin serves as a pivotal regulator of plant growth and development. However, it remains unclear whether the hormone can enhance the uptake of PAHs by plant roots. Hence, the wheat root exposed to PAHs with/without auxins was set to investigate how the auxin promotes the PAHs uptake by roots. In our study, auxin could significantly enhance the uptake of PAHs after 4 h of exposure. After the addition of auxin, the root tissue cytoplasmic pH value was decreased and the H+ influx was observed, indicating that the extracellular space was alkalinized in a short time. The increased H+ influx rate enhanced the uptake of PAHs. In addition, the H+-ATPase activity was also increased, suggesting that auxin activated two distinct and antagonistic H+ flux pathways, and the H+ influx pathway was dominant. Our findings offer important information for exploring the mechanism underlying auxin regulation of PAHs uptake and the phytoremediation of PAH-contaminated soil and water.

Phytotoxicity alleviation of imazethapyr to non-target plant wheat: active regulation between auxin and DIMBOA.

Effectively controlling target organisms while reducing the adverse effects of pesticides on non-target organisms is a crucial scientific inquiry and challenge in pesticide ecotoxicology research. Here, we studied the alleviation of herbicide (R)-imazethapyr [(R)-IM] to non-target plant wheat by active regulation between auxin and secondary metabolite 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazine-3(4H)-one (DIMBOA). We found (R)-IM reduced 32.4% auxin content in wheat leaves and induced 40.7% DIMBOA accumulation compared to the control group, which effortlessly disrupted the balance between wheat growth and defense. Transcriptomic results indicated that restoration of the auxin level in plants promoted the up-regulation of growth-related genes and the accumulation of DIMBOA up-regulated the expression of defense-related genes. Auxin and DIMBOA alleviated herbicide stress primarily through effects in the two directions of wheat growth and defense, respectively. Additionally, as a common precursor of auxin and DIMBOA, indole adopted a combined growth and defense strategy in response to (R)-IM toxicity, i.e., restoring growth development and enhancing the defense system. Future regulation of auxin and DIMBOA levels in plants may be possible through appropriate methods, thus regulating the plant growth-defense balance under herbicide stress. Our insight into the interference mechanism of herbicides to the plant growth-defense system will facilitate the design of improved strategies for herbicide detoxification.

The effect of plant growth regulators on micropropagation of Melientha suavis Pierre. and assessment of genetic fidelity of regenerants based on iPBS and SRAP markers

Abstract. Siringam T, Vanijajiva O. 2023. The effect of plant growth regulators on micropropagation of Melientha suavis Pierre. and assessment of genetic fidelity of regenerants based on iPBS and SRAP markers. Biodiversitas 24: 4628-4634. Melientha suavis Pierre, a significant deciduous edible plant species with high nutritional value and belonging to the Opiliaceae family, holds paramount importance for both agricultural and conservation purposes in its native Southeast Asia. However, the species faces challenges due to habitat fragmentation and negative anthropogenic impacts, leading to a decline in its population. This study aimed to explore the effects of various concentrations of plant growth regulators (cytokinin and auxin) on the shoot and root development of M. suavis, and to assess the genetic stability of micropropagated plants obtained from nodal explants. In vitro shoot regeneration and proliferation were conducted on Murashige and Skoog (MS) semi-solid medium, supplemented with 6-benzylaminopurine (BAP) or kinetin (Kn) at different doses. The optimal shoot length, shoot number, and leaf volume were observed in the modified MS medium with 1.0 mg/L BAP after an 8-week incubation period. Efforts to enhance the rooting of micropropagated shoots included the addition of auxins, such as ?-naphthalene acetic acid (NAA) or indole-3-butyric acid (IBA). However, the species exhibited recalcitrant behavior during the reproduction and rooting stages, as the rooting percentage did not correlate with the increase in auxin concentration. Interestingly, the highest root number and length were achieved in the MS medium without plant growth regulators after 8 weeks of incubation. To ensure genetic fidelity, regenerants were subjected to inter-primer binding site (iPBS) and sequence-related amplified polymorphism (SRAP) marker analysis. The results revealed no genetic variation between the micropropagated plants and the mother trees, confirming the production of genetically stable progeny. Overall, this protocol presents a promising alternative for profitable propagation and establishment of genetically constant progeny of M. suavis, with important implications for sustainable applications and germplasm conservation in Southeast Asia. Addressing the challenges faced by this valuable species through micropropagation and genetic fidelity assessment can contribute significantly to its preservation and utilization for agricultural and conservation initiatives.

Over-Expression of ZmIAA29, an AUX/IAA Transcription Factor, Improved Maize Flowering Time

Maize is one of the most important food and feed crops in China due to the high demand for its use by both humans and animals. The Huang-Huai-Hai region is a major maize cultivation area in China, and the special cropping rotation system of wheat and maize requires a suitable reproductive period for maize. The AUX/IAA and ARF transcription factors are two key genes that regulate auxin signals in plants, which play an important role during the process of auxin regulation in plant growth and development. In this study, we obtained two overexpressed lines of ZmIAA29 belonging to the AUX/IAA transcription factor family. Compared with the Wide type, the overexpressed strains of ZmIAA29 were significantly regulated in maize during the flowering time and had increased ear weight. Moreover, ZmIAA29 was assayed via the yeast two-hybrid and BiLUC systems for interaction, and the results showed that ZmIAA29 interacted with several ZmARF transcription factors. Furthermore, RNA-seq and DAP-seq analysis revealed that ZmIAA29 regulates maize growth and development by influencing pathways such as those for plant signal transduction and the key genes related to maize flowering. Taken together, our results suggest that ZmIAA29 plays a key role in the development of maize flowering. This study provides new insight for better understanding the combined regulation of the AUX/IAA and ARF transcription factors during flowering time in maize.