GATA transcription factor is crucial for plant growth and development, physiological metabolism, and environmental response, which has been reported in many plants. Although the identification of maize GATA genes has been reported previously, the number of maize GATA genes was incomplete, and the expression patterns of maize GATA genes were not analyzed. Therefore, in this study, the GATA gene family of maize (Zea mays L.) was systematically analyzed. Forty-one GATA family genes were identified in the maize and were divided into four groups. The gene structure of each subgroup was basically consistent with that of the motif. The maize GATA genes were distributed on 10 chromosomes, including 3 and 17 pairs of tandem and segmental duplication genes, respectively. Fourteen types of cis-acting elements were identified in the promoter sequences of maize GATA family genes, involving four categories: light response, stress, hormone, and growth and development. The tissue-specific expression analysis of maize GATA family genes revealed that 4 GATA genes were highly expressed in almost all the maize tissues, and 11 GATA genes were not expressed in almost all tissues. The other maize GATA family genes showed a tissue-specific expression pattern. The results of RNA-seq reanalysis of publicly available transcriptome sequencing big data revealed that the gene ZmGATA37 was significantly down-regulated in response to abiotic stresses including high temperature, low temperature, drought, waterlogging, and salt, and significantly up-regulated in response to biotic stresses including smut disease, Maize Iranian mosaic virus infection, beet armyworm and aphid infestations. This indicated that the ZmGATA37 gene plays an important role in maize growth and development. Our findings offer new insight into the potential role of GATA transcription factors in abiotic and biotic stresses and provide a theoretical groundwork for the molecular mechanisms underlying maize adaptation to such stress.

To address the insufficient accuracy of traditional single-sensor navigation methods in dense planting environments of pomegranate orchards, this paper proposes a vision and LiDAR fusion-based navigation line extraction method for orchard environments. The proposed method integrates a YOLOv8-ResCBAM trunk detection model, a reverse ray projection fusion algorithm, and geometric constraint-based navigation line fitting techniques. The object detection model enables high-precision real-time detection of pomegranate tree trunks. A reverse ray projection algorithm is proposed to convert pixel coordinates from visual detection into three-dimensional rays and compute their intersections with LiDAR scanning planes, achieving effective association between visual and LiDAR data. Finally, geometric constraints are introduced to improve the RANSAC algorithm for navigation line fitting, combined with Kalman filtering techniques to reduce navigation line fluctuations. Field experiments demonstrate that the proposed fusion-based navigation method improves navigation accuracy over single-sensor methods and semantic-segmentation methods, reducing the average lateral error to 5.2 cm, yielding an average lateral error RMS of 6.6 cm, and achieving a navigation success rate of 95.4%. These results validate the effectiveness of the vision and 2D LiDAR fusion-based approach in complex orchard environments and provide a viable route toward autonomous navigation for orchard robots.

Electric multirotor plant protection unmanned aerial vehicles (UAVs) are widely used in China for efficient and precise plant protection at low altitude for low volumes. Unstructured farmland in China has various types of obstacles, and UAVs usually use a detour path to avoid obstacles due to flight altitude limitations. However, existing UAV spray systems do not spray when in obstacle neighborhoods during obstacle avoidance, resulting in insufficient droplet coverage and reduced plant protection quality in the area. To improve the droplet coverage in obstacle neighborhoods, this article carries out a study of side spray technology with an electric quadrotor UAV, and proposes the design and development of a side spray device. The relationship between the obstacle avoidance path of the UAV and the spray pattern of the side spray device and their effect on droplet coverage in obstacle neighborhoods was explored. An accurate measurement method of the relative position between the UAV and obstacles was proposed. Spray angle calculations and nozzle selection for the side spray device were carried out in conjunction with the relative position. A rotor wind field simulation model was designed based on the lattice Boltzmann method (LBM), and the spatial layout of the side spray device on the UAV was designed based on the simulation results. To explore suitable spray patterns for the side spray device, comparative experiments of droplet coverage in obstacle neighborhoods were carried out under different environments, spray patterns, and flight parameter combinations. The relationship between the flight parameter combinations and the distribution uniformity of droplets and the effective swath width of the side spray device was explored. The experimental results were analyzed by an analysis of variance (ANOVA) and a relationship model was obtained. The results showed that the side spray device can effectively improve droplet coverage in obstacle neighborhoods compared to a device without side spray using the same flight parameter combinations. The effective swath width in obstacle neighborhoods can be increased by a minimum of 6.35%, maximum of 35.32%, and average of 15.25% using the side spray device. The error between the predicted values of the relational model and the field experiment results was less than 15%. The results verify the effectiveness and rationality of the method proposed in this article. This study can provide technical and theoretical references for improving the plant protection quality of UAVs in obstacle environments.

Aiming to address the problems of low working efficiency and high damage rate of high and low roller peeling equipment in the process of fresh corn harvesting in China, this paper theoretically analyzes the mechanical motion process between the peeling device and the corn ear, and a high–low roll peeling structure is proposed. This structure incorporates elastomeric rubber material, a roller segmentation design, and an adjustable spiral frame, and the selection of relevant parameters is given. To determine the optimal operating parameters for the fresh-corn-peeling device, a three-factor, three-level orthogonal test was conducted using the Box–Behnken central grouping method in Design-Expert 12 software. The test factors were peeling roller speed, peeling roller tilt angle, and vibrating plate frequency. The evaluation indices considered were the bract peeling rate (BPR) and the grain breaking rate (GBR). Based on the theoretical analysis results, a test bench for the fresh-corn-ear-peeling device was established and the parameter combination for optimal peeling quality was determined according to the actual work situation. The results show that the impact on the BPR and GBR, from large to small, is in the following order: peeling roller speed, peeling roller tilt angle, and frequency vibration plate. The optimization module was used to optimize the operating parameters and used the following integers to obtain the optimal operating parameter combination: the peeling roller speed was 480 r·min⁻¹; the peeling roller tilt angle was 8°; the vibrating plate frequency was 260 times·min⁻¹; the corresponding BPR was 91.75%, which was 0.66% points lower than the optimal value; and the GBR was 1.55%, which was 0.08% points higher than the optimal value. Notably, this fresh-corn-peeling equipment exhibited superior performance in terms of peeling fracture results compared with standard peeling equipment. Therefore, this study provides valuable technical support for the optimal design and selection of fresh-corn-peeling equipment.

This paper studied the atomization characteristics of different spray nozzles under the spot spraying method and designed a test system for the atomization characteristics. First, the effective spray height range was determined based on the effective droplet size of 106–403 μm, the spray height of 200–500 mm, the operating speed of 0.5–1 m/s, and the droplet size requirements. The effective height ranges of the HVV25-02, HVV40-02, and HVV50-02 nozzles are 277–500 mm, 200–426 mm, and 200–266 mm, respectively. Second, the influences of pressure, the opening time of the solenoid valve, and the nozzle aperture on the atomization characteristics were studied through experiment. The experiment was repeated three times, with 10,000 points monitored each time. The test results show that the droplet size of spot spraying decreases with the increase in pressure, while the droplet velocity and droplet distribution relative span have no correlation with pressure. With the increase in the opening time of the solenoid valve, the droplet size does not change regularly, the droplet velocity generally shows an upward trend, and the droplet distribution relative span (RS) value decreases gradually. With the increase in the nozzle aperture, both droplet size and droplet velocity increase, and the distribution span shows a trend of first increasing and then decreasing. The droplet velocity of spot spraying is 4.1 m/s lower than that of continuous spraying, on average, and the droplet distribution relative span value is 2.2 higher than that of continuous spraying. This research can provide a basis and reference for the selection of appropriate spot spraying operation parameters.