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Mechanized production plays an important role in fulfilling food security demands during the period of labor shortage. Despite its benefits, the mechanical transplanted method (MET) has not been widely adopted due to a lack of awareness. Thus, this study aimed to evaluate the effect of the MET, the manual transplanted method (MAT), and the directed seeded method (DS) on rice yield and quality in farmers’ fields. A two-years field experiment (2016 and 2017) and a one-year survey (2020) were conducted to compare rice yield and quality among the MAT, MET, and DS methods. MET exhibited a higher-yielding population, increased biomass production, enhanced yield, and improved grain quality, compared with MAT. Moreover, japonica rice in MET (MET-JR) produced the maximum yield, 0.6 t hm−2 to 3.1 t hm−2 higher than in other treatments. However, japonica rice showed a poorer appearance quality than indica rice, as well as large panicle size (grains number per panicle ≥ 190); hybrid indica rice (HIR) also presented a high yield with poor appearance quality. These results confirmed that the application of MET could be useful in attaining high panicles per m2, high biomass production, high rice yield, and considerably improved rice quality in farmers’ fields under labor shortage circumstances. Furthermore, it is also imperative to consider balancing the yield and quality of japonica rice and large panicle HIR and employing MET at a broader scale in China, as well as other developing countries having rice–based cropping systems.

Yield loss of ratoon crops caused by the rolling damage to the left stubble from mechanically harvesting main crops has been reported in previous studies. However, limited attention has been paid to identify the effect of the mechanical harvesting of the main crop on the yield of a non-rolled zone (NRZ) of a ratoon crop. A two-year field experiment on ratoon rice with two harvest methods (mechanical harvesting: MEH; manual harvesting: MAH) of a main crop was conducted to identify whether there is a border effect on the yield of the NRZ, and to evaluate whether the border effect will compensate for the yield loss of the ratoon crop. On average, MEH reduced the grain yield of the ratoon crop by 17.6% compared with MAH. The yield of the rolled zone (RZ) in MEH was 66.1–70.3% lower than that of MAH, which was attributed to the lower panicle m−2, grain filling percentage, total dry weight, and harvest index. In contrast, the yield of the NRZ in MEH was 2.7–10.8% higher than that of MAH. The yield differences of the non-rolled single row (R1), side row (R2), and middle row (R3) in the NRZ compared with MAH were 22.9%, 8.5%, and −10.1%, respectively, which were mainly explained by the panicle m−2, spikelets m−2, total dry weight, and regeneration rate. These results suggest that rolling during the mechanical harvesting of the main crop induced a border effect on the yield of the NRZ, which reduced the yield loss of the ratoon crop. The yield gain of the NRZ was attributed to the increased yield of R1 and R2 rather than R3.