麦秸秆全量还田下耕整地方式对机插水稻产量和品质的影响

为探索麦秸秆全量还田条件下实现水稻增产、品质提高的适宜耕整地方式，于2021-2022年开展大田试验，以迟熟中粳水稻南粳5 718为材料，在麦秸秆全量还田和不还田条件下，设置一体化旱地双轴旋耕整地（T1）、旱地单轴旋耕+水田单轴旋耕整地（T2）、水田单轴旋耕整地（T3）3种耕整地方式，研究麦秸秆还田量与耕整地方式以及两者互作对机插水稻产量和品质特征的影响。结果表明，与麦秸秆不还田相比，麦秸秆全量还田下的水稻产量在T1方式下增加4.54%～5.45%(P<0.05)，在T2和T3方式下降低。3种耕整地方式水稻产量在麦秸秆不还田下表现为T2>T1>T3，在麦秸秆全量还田下表现为T1>T2>T3，其中麦秸秆全量还田下T1处理较麦秸秆不还田的T2处理产量有所提高，但无显著差异。这一结果可能与麦秸秆全量还田与T1处理互作降低了稻田土壤容重、增加了耕作深度和土壤Eh有关，从而促进了水稻有效穗数的增加，提高了成熟期干物质积累量和收获指数，实现了水稻产量的增加。麦秸秆全量还田较不还田降低了各耕整地方式下稻米的垩白面积和垩白度，改善了稻米外观品质；降低了稻米的直链淀粉含量，...

Effects of wheat straw returning and land preparation on rice yield and quality under mechanical transplanting

Mechanical transplanting has been the largest planting mode of rice production, particularly in the rice-wheat double cropping area. But the soil preparation of rotary tillage (ploughing) cannot fully meet the requirements of machine planting in recent years, due to the single function, high failure rate, and low tillage quality. Flat, clean and solid can be expected for the high quality of rice planting and yield. The main purpose of this study is to explore the tillage and soil preparation for the high yield and quality of machine-transplanted rice under the total wheat straw returning. The experiment was carried out in the rice growing season of 2021 and 2022. The rice variety was taken as Nanjing 5718. The straw treatment was selected as the main area, whereas, the tillage was as the sub-area. Among them, the yield of previous wheat was about 7.2 t and 8.3 hm² in the experimental field in 2021 and 2022, respectively, where the amount values of straw were 12.9 and 15.4 t/hm², respectively. Two straw treatments were set: straw without returning to the field (S1) and straw full returning to the field (S2). The straw was removed from the field in the S1 treatment using manual harrowing. The straw was returned to the field in the S2 treatment using rotary tillage. Three tillage modes and land preparation were: integrated dryland biaxial rotary tillage (T1), dryland uniaxial rotary tillage + paddy field uniaxial rotary tillage (T2), and paddy field uniaxial rotary tillage (T3). Some parameters were then determined, including the tiller number, leaf area index, dry matter, grain yield, as well as the processing, appearance and eating quality of rice. The results showed that the rice yield increased by 4.54% to 5.45% (P<0.05) under S2+T1 treatment, compared with the S1, whereas, the rice yield decreased by 1.77% to 2.41% and 4.11% to 6.48% (P<0.05) under T2 and T3, respectively. The rice yield was ranked in the descending order of T2>T1>T3 under the S1 treatment, whereas, the order of T1>T2>T3 was found under the S2 treatment. The rice yield in T1 treatment was depended mainly on the panicles, dry matter accumulation, and harvest index. The total returning of wheat straw was reduced the amylose content, the area and degree of chalkiness for the better appearance quality, protein content, and taste value, compared with the S1. In addition, there was the increase in the peak viscosity and breakdown value of starch, as well as the gelatinization and palatability of rice under the S2. The chalkiness and the taste value were ranked in the descending order of T2>T3>T1, and T1>T2>T3, respectively. The taste value under the T1 increased by 3.36%-5.90%, 7.44%-11.30%, and 1.38%-4.65%, 6.28%-11.23%, respectively, compared with the T2 and T3. In summary, the T1 treatment was greatly contributed to synergistically improve the rice yield, appearance quality, nutritional quality, and taste value of machine-transplanted rice under the total wheat straw return. The finding can provide the data and theoretical support for the integrated single tillage under the full return of wheat straw to the field in the rice wheat double cropping area during mechanical transplanting.