Potato is an important food crop in China, and its planting area and output rank first in the world. Due to the labor intensity and low efficiency of manual harvesting, mechanized harvesting has become an inevitable solution for the development of the potato industry. In this paper, on the basis of elaborating on mechanized harvesting operation modes for potatoes, the research progress of key technologies, such as top-killing potato seedlings, low-loss digging with reduced obstruction, limiting the depths of rows, high-efficiency separation, sorting tons of packages, and intelligent harvesting in China and abroad, is analyzed. By comparing the basic structure and technical characteristics of both domestic mechanized potato-harvesting equipment and that used abroad, this paper identifies the gaps between domestic equipment’s performance, intelligence level, and adaptability and those of equipment in European and American countries and also identifies bottlenecks, such as large regional variability, the lack of high-efficiency and low-loss separating devices, and the difficulty of breaking through key “chokepoint” technologies. On this basis, this paper proposes that the future development direction of domestic mechanized potato harvesting should focus on the synergistic development of multiple modes, on the research and development of flexible and low-loss separation equipment, and on the integration of intelligent technology; it also gives specific suggestions, aiming to provide references for the future progress of mechanized potato harvesting.

To address the fact that existing studies may not be able to accurately describe the discrete element parameters of the soil during the potato harvesting period and to improve the accuracy of the potato harvesting equipment simulation studies, this study was conducted on the soil around the harvested potato tubers in the field. The simulation parameters of the discrete element model of soil were determined by the soil stacking angle test and soil block shear crushing test with the actual test measurements as the target. Based on a series of experimental designs, the factors affecting the stacking angle were the static friction coefficient and the rolling friction coefficient between soil particles; and the rolling friction coefficient between soil and steel. The factors affecting the maximum shear damage force were normal stiffness and shear stiffness per unit area. The quadratic regression equations were established and solved to obtain the optimal discrete element simulation parameters. The results can provide more realistic and reliable parameters for the construction of soil simulation models of potato fields during harvesting and for the discrete element simulation of soil-touching components of potato harvesting equipment. It can also further enrich the parameter data of soil discrete element simulation models and provide a reference for related research

Peanut is China’s most competitive oil and cash crops internationally. Furthermore, China’s peanut production is the largest in the world. Hence, the peanut industry plays an important role in the national economy. To address the problems of high rates of broken and unharvested pods during peanut harvesting, we researched the dynamic characteristics of harvesting and the mechanisms that influence operation quality. Considering the typical peanut varieties in China’s main peanut-producing areas as the study objects, we studied the mechanical properties of peanut in relation to the harvesting process. By adopting the Box-Behnken design, we set the harvesting net rate Y1, breakage rate Y2, and entrapment loss rate Y3 as the evaluation indices. We performed response surface testing on the peanut-harvesting roller speed, longitudinal size of concave sieve holes, peanut harvesting gap, and feeding volume. Through field verification testing, the parameters for maximum performance were obtained. When the picking roller speed was 260 r/min, the longitudinal dimension of the concave grate sieve pores was 90 mm, the harvesting gap was 40 mm, and the feed rate was 3.3 kg/s. Moreover, the harvesting net rate, breakage rate, and entrapment loss rate were 94.61%, 3.78%, and 0.85%, respectively. Verification testing was carried out based on the optimal parameters, and the results showed that the harvesting net rate, breakage rate, and entrapment loss rate were 95.73%, 3.54%, and 0.84%, respectively. A comprehensive scheme to optimize the peanut harvesting process was proposed to overcome harvesting problems and improve harvest quality. The study conclusions provide theoretical guidance for developing improved tangential-flow peanut-harvesting technology and equipment.

To address the inadequacies of mechanized potato-harvesting equipment on challenging terrains like hills, mountains, and small fields, a lightweight and simple self-propelled crawler potato combine harvester was developed based on the agronomic and harvesting requirements of potato cultivation. The machine consists of key components including a depth-limited soil-crushing device, an auxiliary feeding device, an excavation device, a rubber rod separation device, and a ton bag sorting device. It offers technical advantages such as a lightweight structure, auxiliary feeding and conveying, and manual assistance in sorting ton bags. The key components, such as the auxiliary feeding device, depth-limiting soil-crushing device, and rubber rod separation device, were analyzed theoretically to determine the relevant structures and parameters. Through initial harvesting performance tests, the separation screen line speed, vibration frequency, and device inclination angle were identified as the experimental factors. Evaluation indicators such as potato bruise rate, skin breakage rate, loss rate, and impurity content were chosen, and a three-factor, three-level Box–Behnken optimization test was conducted. The results indicated that with a separation screen line speed of 1 m/s, vibration frequency of 8 Hz, and device inclination angle of 30°, the potato damage rate during harvesting was 1.318%, the skin breakage rate was 1.825%, the loss rate was 2.815%, and the impurity rate was 2.736%. Field tests with the same parameters showed that the potato damage rate, skin breakage rate, loss rate, and impurity rate of the harvester were 1.357%, 1.853%, 2.86%, and 2.748%, respectively, meeting relevant industry technical standards. This research can serve as a reference for enhancing the harvesting performance of potato combine harvesters and ton bag sorting technology.

Preharvest bagging is a key agricultural technology in the process of the growth and development of young fruits. It can effectively improve the appearance quality of fruits, reduce pesticide residues on the surface of fruits and prevent pests and birds from harming fruits. China is one of the world’s major fruit producers. It is also the country that uses the most fruit cultivating bags. At present, the fruit cultivating bags used in Chinese orchards are mostly paper. Ways to recycle and reuse the waste fruit cultivating bags should be paid attention to. Therefore, this paper comprehensively uses the methods of data analysis and literature research to summarize and analyze. The data mainly comes from the China Rural Statistical Yearbook, a national public service platform for standard information, China’s national knowledge internet and the web of science. The topics discussed include the current situation of fruit production in China, the overview of fruit bagging technology, the production and use of fruit cultivating bags and the recycling strategy of waste fruit cultivating bags. It is hoped that this study can provide some references to the development of fruit bagging technology and the resource reuse and recycling of waste fruit cultivating bags in China and the world in the future.

Tractors are widely used self-propelled power machinery. Electrification is one of the main directions for the green and low-carbon development of tractors. Currently, electric tractors have become one of the main research hotspots in countries around the world. This study provides a comprehensive review of the research progress on electric tractors in China. Firstly, a brief analysis is conducted on the development history of electric tractors, the current research status in other countries around the world, and the situation regarding China’s tractor industry. Secondly, the classifications and characteristics of electric tractors are summarized. We focused on the research progress of electric tractor motors and their drive transmission systems, batteries, and energy management technology, as well as other key technologies. Finally, some opportunities and challenges faced by the development of electric tractors in China are pointed out from the aspects of market demand, national policies, and standard setting.