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HighlightsThe designed precision seeder meets the agronomic requirements for on-film hole seeding.Influencing factors were found by studying the operating principle and key parameters.A response model was successfully built and verified by experiments.This study provides technical support for punching-on-film hole seeding technology.Abstract. To satisfy the agronomic requirements for punching-on-film precision seeding of peanuts, a precision hole seeder was designed in this study. The seeder can perform simultaneous functions of film mulching, film punching, pipe laying, precision hole seeding, and seed covering. The overall structure and operating principle of the device were analyzed, and its major components, including a seed-metering device, soil-covering roller, and drip irrigation pipes, were theoretically studied. To optimize the operating parameters and achieve favorable performance, a three-factor quadratic orthogonal test was performed to test the effects of the vacuum chamber pressure, advancing speed of the seeder, and height of the type hole boss on the seeding performance; the variance and range of the test results were analyzed accordingly. Through the field experiments, when the vacuum chamber pressure, advancing speed of the seeder, and height of the type hole boss were optimized to 7.5 kPa, 4.2 km h-1, 5.3 mm, respectively, the qualification index, re-seeding index, and miss-seeding index of the seeder were 92.7%, 3.8%, and 3.5%, respectively. Thus, the developed seeder satisfies the agronomic requirements, and the study results provide a technical reference for the punching-on-film precision seeding of peanuts. Keywords: Model, Peanut, Precision seeding of peanut, Punching-on-film hole, Seeder.

Mechanical-chemical synergy has been proven efficient in weed control. However, characterizing the state of the weed–soil complex after mechanical weeding and revealing its effects on subsequent herbicide application is still challenging, which restricts the implementation of this technology. This paper first presents a method to characterize the state of the weed–soil complex from the perspectives of the fragmentation and composite characteristics. The regrowth of the weed–soil complex and the effects of complemented herbicide-reduced spraying on weed control efficacy and crop yield were then investigated. The results showed that the typical diameters of the weed–soil complexes were 10.67 cm and 2.82 cm after inter-row hoe shovel and intra-row finger weeding, respectively. There were mainly two and four weed–soil complex states after inter-row and intra-row weeding, respectively. The regrowth rate corresponding to the weed–soil complex state with the largest component proportion after inter-row and intra-row weeding was 76.91% and 18.37%, respectively. The additional chemical herbicide sprayed on the weed–soil complex significantly improved the fresh weight control efficacy of 95.12% for the preposed inter-row mechanical weeding and 138.07% for the preposed intra-row mechanical weeding in the maize silking stage. The maize yield of inter-row mechanical–75% chemical application treatment was 9.27% higher than that of chemical treatment. Mechanical weeding creates a suitable weed–soil complex state for subsequent chemical application and improves the synergistic weeding effect.