新育成超短生育期品系在双季稻双直播下的产量表现及农艺特性

Yield performance and agronomic characteristics of a newly developed ultrashort-duration line in direct-seeded double-season rice system

为探究新育成超短生育期品系在双季稻双直播模式下的产量表现及关键的高产农艺特性,本研究以超短生育期新品系CPPC18和4个对照品种(湘早籼6号、早籼615、中早39和两优152)为供试材料,2021年在湖北黄冈进行双季稻双直播的小区试验和生产示范,测定冠层光照拦截、干物质积累、倒伏特性、产量和产量构成因子等农艺性状。试验结果表明,超短生育期新品系在双季稻双直播模式下早晚兼用的单季生育期在95d以内,周年生育期为180~183 d,这比湘早籼6号早晚兼用增加7~9 d,而比早籼615早晚兼用和中早39与两优152早晚搭配分别缩短4~8d和16~22d。在小区试验中,超短生育期新品系CPPC18的周年产量相比其他品种增加7.2%~14.6%,达到14.9t hm^(-2)。超短生育期新品系较高的周年产量主要得益于其早季较强的早发特性和晚季较高的单位面积颖花数、结实率和收获指数。此外,超短生育期新品系具有比其他品种更强的抗倒伏能力,这主要得益于其较低的株高、重心高度和弯曲力矩。在生产示范中,超短生育期新品系的周年产量同样表现出明显优势,相比其他对照品种增产12.7%~21.6%。综上所述,超短生育期新品系CPPC18能够满足华中地区双季稻双直播高产稳产要求,具有良好的推广前景。

The objective of this study is to explore the yield performance and yield-related traits of a newly developed ul-trashort-duration line in direct-seeded double-season rice system.An ultrashort-duration line named CPPC18,and four check cul-tivars(Xiangzaoxian 6,Zaoxian 615,Zhongzao 39,and Liangyou 152)were grown as the direct-seeded double-season rice in both plot-level and on-farm experiments in Hubei province in 2021.We measured canopy light interception,biomass accumula-tion,lodging characteristics,yield,and yield components.The result showed that the new line matured within 95 days in each season,and its annual growth duration was 180–183 days.This was 7–9 days longer than Xiangzaoxian 6,but 4–8 days and 16–22 days shorter than Zaoxian 615 and the combination of Zhongzao 39(early season)and Liangyou 152(late season),respectively.In the plot-level experiment,the annual yield of CPPC18 reached 14.9 t hm^(–2) and increased by 7.2%–14.6%compared with other cultivars.Yield advantage of CPPC18 was mainly attributed to its early vigor in early season and higher spikelets per m^(–2),grain filling percentage,and harvest index in late season.Besides,the lodging resistance of CPPC18 was stronger than other cultivars due to its lower plant height,the center of gravity height,and bending moment.Similarly,CPPC18 also had yield advantages over other cultivars in the on-farm experiment.The annual yield increased by 12.7%–21.6%over other cultivars.In conclusion,the newly developed ultrashort-duration line CPPC18 was suitable for direct-seeded,double-season rice system in central China for achieving high and stable yield.