This article analyzes and discusses the results of interviews with Japanese organic farmers regarding their farm practices from the perspectives of co-production and autonomy, which are concepts of ploeg’s peasantry in European sociology of agriculture.

As a result, it was confirmed that the farm practices of the organic farmers were developed with social relations in agricultural production as the key factor of co-production, and that the utilization of natural and social resources were balanced, interacted, and transformed to form their own organic farming practices.

It was observed that organic farmers, who are in charge of organic farming, evaluated peasantry and family farming in terms of the maintenance and conservation of their own agriculture, natural resources, and social resources in the practice of their farms. This situation suggests the direction of redefinition of organic farming. In addition, critical opinions were formed from the viewpoints of the impact of large-scale and corporatization of agriculture and the maintenance and conservation of agricultural resources, and in response, evaluations of peasantry and family farming were simultaneously observed.

Methane (CH₄) and nitrous oxide (N₂O) fluxes, soil physicochemical properties, as well as the diversity and molecular phylogenetic analysis of methane monooxygenase gene (pmoA) and ammonia monooxygenase gene (amoA) were investigated in an experimental field where cabbage had been grown twice a year for 17 years. Treatments were grass compost and organic garden soil mix made from soil, rice bran and rapeseed oil cake (GOF), cattle manure compost (CMC), and chemical fertilizer (CF). Area-scaled CH₄ uptake was correlated with bulk density and pore porosity of soils, and that in the GOF was significantly higher than the other treatments. The pmoA sequences amplified from genomic DNA extracted from the GOF and CMC were closely related to the genera Methylocaldum and Methylocystis, in addition, some of the pmoA sequences in the CMC and CF were closely related to those detected by culture-independent methods. It was possible that the diffusion of CH₄ into the soil of the GOF increased and then MOB communities may have developed. Although N₂O flux was positively correlated with the content of inorganic nitrogen in soil of each plot, area-scaled N₂O emissions were not significantly different between the treatments. The ratio of N₂O emissions to input N in the GOF was the lowest and significantly different to that in the CF. The amoA sequences of ammonia-oxidizing bacteria (AOB) were closely related to the genera Nitrospira and Nitrosomonas in the GOF and CMC, whereas those were closely related to the sequences detected by culture-independent methods in the CF. Most of the amoA sequences of ammonia-oxidizing archaea (AOA) were closely related to the sequences detected by culture-independent methods in all treatments. Moreover, the sequences of the compost-applied treatments were genetically distant to those of the CF. These differences in microbial community involved in ammonia oxidation were responsible for relatively low N₂O emission in the GOF.

Weeding is a major problem for the development of organic tea cultivation. In this study, we investigated the current weeding methods used by leading farmers who have long been at the forefront of organic tea cultivation more than 20 years. The weeding methods used by organic tea farmers were categorized into three: 1) weeding with intensive weed removal, 2) extensive weeding with removal of only large weeds, and 3) weeding using a hammer mower. Although intensive management reduced the number of weeds, there is a risk of increasing noxious and climbing weeds. Extensive weeding resulted in the emergence of tall weeds, but cover degree was low. Mechanical management suppressed the cover degree of noxious weeds through chickweed (Stellaria neglecta) dominance.