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By using PacBio HiFi technology, we produced over 700 Gb of long-read sequencing (LRS) raw data; and by using Illumina paired-end whole-genome shotgun (WGS) sequencing technology, we generated more than 70 Gb of short-read sequencing (SRS) data. With LRS data, we assembled one genome and then generate a set of annotation data for an early-matured Geng/japonica glutinous rice mega variety genome, Longgeng 57 (LG57), which carries multiple elite traits including good grain quality and wide adaptability. Together with the SRS data from three parents of LG57, pedigree genome variations were called for three representative types of genes. These data sets can be used for deep variation mining, aid in the discovery of new insights into genome structure, function, and evolution, and help to provide essential support to biological research in general. [ABSTRACT FROM AUTHOR]

An accurate simulation model is crucial for the analysis of the correct modal information of the ginkgo seed–stem system (ginkgo subsystem). This underpins the provision of technical rationale for efficient and low-damage precision vibrational harvesting operations in ginkgo cultivation. In this study, based on the modal parameters of the ginkgo subsystem, a finite element model updating method is proposed to correct the elastic modulus of the stem with the natural frequency of the first bending mode. The large difference in the modal results calculated before and after model updating reveals that model updating is a critical step in the finite element analysis of crop subsystems. Then, an uncertainty parameter modeling method is proposed to investigate the modal variability of the ginkgo subsystem by finite element analysis. The results show that the stem length is a key parameter affecting the variability of natural frequencies, and the seed weight is a minor parameter. The variability of the ginkgo seed's gravity center offset has a negligible effect on the natural frequencies of the system. The first natural frequency of the ginkgo subsystem can be utilized for vibrational harvesting. In addition, since the difference between the upper and lower limits of the first natural frequency of the ginkgo subsystem does not exceed 1 Hz, a specific excitation frequency can cause most ginkgo subsystems to resonate. This result facilitates the determination of precise excitation frequencies for efficient and low-damage ginkgo vibrational harvesting, ensuring both economic and ecological benefits in the management of ginkgo plantations. [ABSTRACT FROM AUTHOR]

Sweetness is one of the most important quality traits for fruit which directly affects consumers' acceptance. The aim of this study was to detect and grade sweetness levels of intact peaches and nectarines by combining short-wave and long-wave Fourier-transform near-infrared spectroscopy (FT-NIRS). FT-NIR spectra of 720 samples (360 peaches and 360 nectarines) were collected using a system operated in range from 15,700 to 4000 cm−1. Soluble solids contents (SSC) were measured as indicators and samples were individually grouped into three sweetness levels based on predetermined thresholds. Partial least squares regression (PLSR) and principal component regression (PCR) were compared, and results showed that PLSR models developed using raw full spectra performed best with correlation coefficient (Rp) of 0.7747 and 0.8473, and root mean square error (RMSEP) of 0.6915% and 0.7228% in prediction. Furthermore, effective wavelengths were individually selected using regression coefficients (RC) and competitive adaptive reweighted sampling (CARS) to simplify the PLSR models. Through comparison, RC-PLSR resulted in comparable performance with original models showing Rp = 0.7716 and 0.8157, and RMSEP = 0.6943% and 0.7945%. To grade different sweetness levels, two-dimensional correlation spectroscopy (2D-COS) was innovatively conducted, and autopeaks characterizing the differences among different groups were retained. Partial least square discriminant analysis (PLS-DA) classification models based on autopeaks achieved a total correct classification rate (CCR) of 66.7% and 86.6% for peaches and nectarines, respectively. The overall results indicated the combination of short-wave and long-wave FT-NIRS was potentially useful in detecting and grading sweetness for these fruit varieties. [ABSTRACT FROM AUTHOR]

Mechanical harvesting is the most effective method for the forest fruit harvesting. Under forced vibration, the removal of fruits is affected by not only the excitation amplitude, frequency, and duration, but also the morphology and inherent frequency spectrum characteristics of the fruit tree itself. In order to discover the relationship between the frequency spectrum characteristics and the vibration responses and attain the difference among the vibration responses in different directions, the frequency spectrum of a small Y-shaped Ginkgo biloba tree in different directions was tested under the impact excitation in the laboratory. Then the spatial acceleration response under the harmonic excitation was detected at the frequency of the peak and trough points in the frequency spectrum curves. Results of this study indicate that there was a corresponding relation between the frequency spectrum characteristics and vibration responses. Strong vibration response couldn’t be induced by the fundamental frequency and the frequency lower than 10.00 Hz. The maximal amplitudes could be tested at the resonant frequency but the values were small at low frequency and increased as the excitation frequency increased. When the excitation frequency was higher than 25.00 Hz, stronger acceleration response couldn’t be induced again. The optimal excitation frequency was 23.75 Hz for the small Y-shaped Ginkgo biloba tree. At the same testing position, vibration responses in three directions exhibited the similar characteristics but different amplitudes. The acceleration amplitude in the direction parallel to the growing orientation of trees increased significantly as the testing position was located away from the excitation point. At the same time, this direction was the dominant direction during the process of the vibration response transmission. This suggests that during the mechanical harvesting of forest fruits, the frequency spectrum of trees could be firstly tested to obtain the resonant frequency. Then trees could be excited under the certain resonant frequency to achieve strong vibration response. Higher excitation frequency didn’t necessarily induce stronger vibration response. There was difference among different directions at the same testing position and fruits on different positions could be removed by the inertial force in different directions. [ABSTRACT FROM AUTHOR]

In order to improve the utilization rate of pesticides and reduce the pesticide pollution to the environment, the control system of the automatic target spray was designed to focus on a Chinese low level of mechanization about the orchard sprayer and the invalid spray existed in the gap of fruit trees when the orchard sprayer sprayed with a continuous spray method. Whether the automatic target spray system sprayed to the fruit trees, depended on the detection distance between the orchard sprayer and the fruit trees by the application of distance measuring sensors and control program, which was installed on the GY8 caterpillar self-propelled orchard sprayer manufactured by Nantong Guangyi Mechanical & Electrical Co, Ltd. This paper compared the properties of three kinds of sensors which were MB7060 ultrasonic sensor, GP2Y0A710K0F infrared sensor and DT35-B15251 laser sensor, and tested the discernible spacing for the ultrasonic sensor and the laser sensor. The laser sensor was chosen as a detection device of the orchard sprayer for its high stability, fast response and good direction, while the other two sensors were abandoned for the following reasons that the infrared sensor was seriously affected by the sunshine, and the discernible spacing of ultrasonic sensor was too wide to satisfy the working conditions of the orchard sprayer. The parameters of the target range for spray trees could be adjusted in the system of the automatic target spray, based on different planted size (spacing in the rows and spacing between rows) of an orchard and the different travel speed of the orchard sprayer. The automatic target spray system could distinguish whether the fruit tree, or the gap between fruit trees and the gap in the canopies, so as to effectively control pests with the minimum dose of pesticide and the least environmental pollution. To ensure that the droplet could cover the whole canopy, the orchard sprayer must start to spray before the nozzle assembly reached the fruit trees and stopped spraying after the nozzle assembly leaves the fruit trees, so the laser sensor was installed in front of nozzle assembly 220 mm and delayed a period of time on the basis of the travel speed to stop spraying after the nozzle assembly left the fruit trees by calculation. The experiment of the discernible spacing of the automatic target spray system and field experiment was tested in the Jiamu forest farm in Aksu of Xinjiang. The results showed that the value of the minimum discernible spacing was lower at higher travel speed to lower travel speed. The discernible spacing of the automatic target spray system was 100-150 mm under the travel speed 0.5 m/s and 200-250 mm under the travel speed was 1.0 m/s. The saving rate of pesticides increased with the increase of the gap rate. Compared with continuous spray, the automatic target spray could save pesticides 27.9%, 53.7%, 76.9 % at the travel speed of 0.5 m/s and 27.3%, 54.5%, 81.0% at the travel speed 1.0m/s, respectively for the gap rate 20.0%, 35.2%, 52.9%. The saving rate of pesticides was higher than the gap rate of the fruit trees, because the pressure of the spray unit was low as the pesticide valve on initially. It is a favorable condition to save pesticide corresponding to thin canopy. Thus, the automatic target spray system of the orchard sprayer could effectively improve the utilization rate of pesticides. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop a label free electrochemical immunosensor for detection of pesticide chlorpyrifos (CPF) in agricultural products. The surface modification of sensors consisted of three successive steps: 1) surface cleaning; 2) increasing the surface coverage of hydroxyl groups; 3) silanization. The CPF hapten conjugate used as recognizing elements were immobilized on the surface of an electrode. Cyclic votammetry was investigated before and after hapten coating, which that confirmed CPF hapten could be successfully coated on the electrodes. The spiked CPF solution was diluted into various folds and mixed with an CPF antibody solution. The detection method was based on an indirect competitive reaction of a limited anti-CPF polyclonal antibody in a sample solution with immobilized hapten, and with a pesticide analyte in the sample solution. The antibody-antigen affinity interactions were investigated by impedance spectroscopy and quartz crystal microbalance. Impedance measurements were performed using a three-electrode setup, which consisted of a gold electrode as a working electrode, a platinum auxiliary electrode, and an Ag/AgCl reference electrode. For impedance measurement, a sine-modulated AC potential with an amplitude of 5mV was applied to the modified electrodes. The Faradic impedance spectra were recorded in the frequency range from 1Hz to 100 kHz, respectively. The semi-circle diameter in the Nyquist plot represented the electron-transfer resistance in an equivalent circuit, decreased with increasing analyte concentrations. For the QCM test, a crystal electrode was mounted in the base of a cylindrical test cell using an "O-ring". One face of the crystal was exposed to the test liquid, while the other was exposed to air. After the antigen modified chips were reacted with the mixture, the variations between the initial and final resonance frequency in PBS was recorded. The signal response of the biosensing system to pesticide CPF concentrations was linear, with the range tested from 0.01-10 μg/mL, with the correlation coefficient of 0.98. The result indicated that EIS was capable of monitoring the change in electron-transfer resistance resulting from anti-CPF antibody-antigen interaction. QCM was also the ideal tool for probing antigen-antibody molecular recognition. The immunosensor can be suited to the detection of pesticide residues in agricultural products, such as Chinese green vegetables and apples. The immunosensor was shown to be sensitive, accurate, rapid, and economical, thus providing a viable alternative to current pesticide detection methods. The systems can be used to determine pesticide CPF down to 0.01 μg/mL. The recovery rate was more than 85 percent. The total detection time was less than 1 h. The mean within-assay variability of detected results was less than 5 percent. It can be used repeatedly after sensor generation. [ABSTRACT FROM AUTHOR]

Features of a truck-mounted fogger powered with a steady combustor are high efficiency, low usage, and low cost in control of forestry pest insects and diseases. The structure parameters of its exhausted tube are the key factors to affect oil solvent insecticide to atomize thermodynamically. We studied 3 types of atomizers: ring atomizer, coniform atomizer and column atomizer; 6 location points for the ring atomizer placed inner of the exhausted tube from 250 to 500 mm away from the exit of the exhausted tube; 3 structure parameters of a ring atomizer as jet flow direction of the orifices, orifice number and diameter; 3 jet flow directions as parallel to airflow, to center of pesticide ring and at 45° to airflow direction; 3 different diameters of exhausted-tubes as Φ70, Φ90, and Φ110 mm, which the experiment for atomizing effect was done respectively. The results showed that the ring atomizer was most effective in thermal atomizing; there were the defect phenomena with a coniform atomizer or a column atomizer, such as dropping liquid at the exit of the exhaust tube and combusting flame in the fog. However, the atomizing effect with the coniform atomizer was better than that of the column atomizer. The thermal fogging concentrate can atomize completely to uniform, fine droplets whose size distribution was in a narrow range of 4-6 μm, when the ring atomizer was positioned inner a Φ70 mm exhaust tube and in the range of 250-350 mm away from the exit of the exhaust tube. With the Φ90 mm or Φ110 mm exhausted tube, there were two droplet distribution regions: 4-7 μm for the fine droplet group whose volume ratio to total droplet volume was less than 16%, and 7-226 μm for the coarse droplet group,. The vast majority of coarse droplets could not be completely atomized thermodynamically. The relative span of droplet was only 0.18μm for the Φ70 mm exhaust tube, but were much higher (2.48 and 2.65μm) for the Φ90 and Φ110 mm exhaust tubes respectively. The parameters for a ring atomizer, such as the diameter, number and jet flow direction of the orifices basically did not affect the thermal atomizing performance. Thus, in the process of thermal atomizing for hot fogging concentrate, atomizer type, the exhaust tube diameter, and the position of the atomizer were the main factors influencing the performance of a thermal atomizer. [ABSTRACT FROM AUTHOR]

The deterioration of global environment, decreasing of biological diversity, increasing of natural disasters, exhausting of biological resources and acceleration of desertification emphasize the need to provide the human-beings with the suitable environments. Nowadays, precision agriculture and precision forestry have been emphasized to obtain the maximum output with minimum input and the least impact on the environment, so agricultural and forestry engineering systems require multi-disciplinary design groups to deal with some common interests and the concept of biomechinfotronics is needed. The word "biomechinfotronic" is introduced to describe the multidisciplinary aspects of this complex system. In the paper, the prospects, mission analysis, education system, research areas of biomechinfotronics are studied. The particular characteristics of biomechinfotronics are the synergistic integration of biological engineering with mechatronics, bioinformatics, infotronics, bioelectronics and intelligent computer systems for conducting common research and development and for recruiting and training students with wide specialties. [ABSTRACT FROM AUTHOR]