杂交水稻

为探究不同机收方式对再生稻产量和品质的影响，于2023—2024年开展大田试验，以隆晶优1212(高节位再生型品种)和甬优4949(低节位再生型品种)为供试品种，设置常规水稻收割机收获和再生稻专用收割机收获2种机收方式处理，测定头季机收碾压率、头季和再生季产量及产量构成因素与再生季稻米品质等指标。结果表明，相比于常规水稻收割机收获方式，采用再生稻专用收割机收获的，头季机收碾压率从44.3%降至22.7%。在再生稻专用收割机收获方式下，隆晶优1212和甬优4949再生季2 a平均产量分别为3.91、5.26 t/hm²，分别较常规水稻收割机收获方式增产17.4%、10.5%。与常规水稻收割机收获方式相比，头季采用再生稻专用收割机收获的，再生季有效穗数、单位面积颖花数和结实率分别提高10.2%、7.0%和7.1%，而每穗颖花数和千粒重差异不显著。从稻米品质来看，相比于常规水稻收割机收获方式，头季采用再生稻专用收割机收获的，2个品种再生季平均整精米率提高2.4%，平均垩白粒率和垩白度分别降低21.0%、15.2%；在再生稻专用收割机收获方式下，隆晶优1212和甬优4949较常规水稻收割机收获的整精米率分别提高4.1%、1.0%，垩白粒率分别降低19.7%、22.5%，垩白度分别降低19.2%、10.0%。比较碾压行的再生季产量和稻米品质发现，相较于隆晶优1212，甬优4949碾压行的年平均产量提高23.5%，整精米率提高25.2%，垩白粒率和垩白度分别降低12.0%、22.2%。综上，头季采用再生稻专用收割机收获，可显著降低机收碾压率，进而提升再生季产量和稻米品质，对高节位再生型品种的改善效果更佳。

To investigate the effects of different mechanical harvesting methods on the yield and grain quality of ratoon rice, a field experiment was conducted from 2023 to 2024 with Longjingyou 1212(a high-node ratoon rice variety) and Yongyou 4949(a low-node ratoon rice variety). Two harvesting methods—the ordinary rice harvester and specialized harvester for ratoon rice—were applied. Key indicators, including the stubble damage rate in the main season, yields and yield components in the main and ratooning season, and grain quality in the ratooning season, were measured. The results showed that compared with the ordinary harvester, the specialized harvester used in the main season reduced the stubble damage rate from 44.3% to 22.7%. Under the specialized harvester treatment, the two-year average yields of Longjingyou 1212 and Yongyou 4949 in the ratooning season were 3.91 t/hm2 and 5.26 t/hm2, representing increases of 17.4% and 10.5%, respectively, compared with those under the ordinary harvester treatment. Further analysis revealed that compared with the ordinary harvester, the specialized harvester used in the main season increased the effective panicles, spikelets per unit area, and grain filling rate by 10.2%, 7.0%, and 7.1%, respectively, while causing no significant difference in spikelets per panicle or 1 000-grain weight in the ratooning season. In terms of grain quality, compared with the ordinary harvester, the specialized harvester used in the main season improved the average head rice rate by 2.4% and reduced the average chalky grain rate and chalkiness degree by 21.0% and 15.2%, respectively, of two varieties in the ratooning season. Compared with the ordinary harvester, the specialized harvester used in the main season increased the head rice rates by 4.1% and 1.0%, decreased the chalky grain rate by 19.7% and 22.5%, and reduced the chalkiness degrees by 19.2% and 10.0% for Longjingyou 1212 and Yongyou 4949 in the ratooning season, respectively. Regarding the track rows, Yongyou 4949 showed an increase of 23.5% in annual average yield, an increase of 25.2% in head rice rate, and reductions of 12.0% and 22.2% in chalky grain rate and chalkiness degree, respectively, compared with Longjingyou 1212 in the ratooning season. In conclusion, using a specialized harvester in the main season significantly reduced the stubble damage rate, thereby enhancing the yield and grain quality in the ratooning season, with more pronounced benefits for high-node ratoon rice varieties.