以甬优系列籼粳杂交稻中熟类型品系为试材,常规粳稻宁粳3号和武运粳29、杂交籼稻丰两优香1号和新两优6380为对照,比较各类型在穗部特征、叶片形态以及茎秆特性上的差异。结果表明,1)依据甬优系列籼粳杂交稻两年中的产量表现,将其分成高产品系(产量>10.5 t/hm²)和中产品系(产量<10.5 t/hm²)。两年中,甬优系列籼粳杂交稻高产品系为甬优2638、甬优2640、甬优1610、甬优1612和甬优1640,中产品系为甬优1851、甬优1852、甬优7753、甬优1763和甬优 5854。产量构成因素方面,不同类型品种单株穗数、结实率和千粒重以常规粳稻最高,每穗粒数以高产品系最高。2)穗长以杂交籼稻最高,单穗重和着粒密度以高产品系最高;除穗下部二次枝粳籽粒数以杂交籼稻最高外,穗部其余5部位籽粒数均以高产品系、中产品系显著高于常规粳稻和杂交籼稻,且籽粒数以上部二次枝粳和中部二次枝粳的增加最为明显。3)上三叶的叶长和叶宽为中产品系>杂交籼稻>高产品系>常规粳稻,高产品系上三叶的卷曲率高于对应的中产品系;上部第1、2叶的叶基角和披垂角以高产品系最低。4)高产品系株高为118.7cm,高于常规粳稻(96.6cm),低于杂交籼稻(132.9cm)和中产品系(144.1cm);上部第1、2、3节间长度以中产品系最高、常规粳稻最低;穗长与穗下节间长占株高比例、穗下节间占秆长比例均以高产品系最低。单茎干质量、单茎鞘干质量、茎秆单位节间干质量以高产品系最高。提出了甬优籼粳交中熟高产品系的株型选育指标及配套高产栽培措施。

A field experiment was conducted using Yongyou japonica/indica hybrids with medium maturity as material, conventional japonica rice (CJR) Ningjing 3 and Wuyunjing 29, hybrid indica rice (HIR) Fengliangyouxiang 1 and Xinliangyou 6380 as the check. Differences in panicle, leaf, and culm traits of various rice types were compared. The results were follows: 1) Yongyou japonica/indica hybrids were divided into two types:high-yielding lines (HYL,over 10.5t/hm²) and medium-yielding lines (MYL,less than 10.5t/hm²) based on yield performance. HYL includes Yongyou 2638, Yongyou 2640, Yongyou 1610, Yongyou 1612, and Yongyou 1640, while MYL includes Yongyou 1851, Yongyou 1852, Yongyou 1763, Yongyou 7753, and Yongyou 5854. CJR had the highest number of panicles, seed-setting rate, and 1000-grain weight, while HYL had the highest spikelet number per panicle. 2) HIR had the longest panicle length, while HYL had the highest grain weight per panicle and grain density. HIR had the highest number of spikelets on the low secondary rachis branches,while HYL and MYL had the highest number of spikelets in other panicle positions, especially on the upper secondary rachis branches and the middle secondary rachis branches of panicle. 3) Leaf length and width of the top-three leaves followed a tendency of MYL>HIR>HYL>CJR. HYL had consistently higher rolling rate of top-three leaves than MYL. HYL had the lowest leaf basic angle and dropping angle of the 1^st and 2^nd leaf from the top. 4) Plant height of HYL was 118.7 cm, higher than CJR (96.6 cm), shorter than HIR (132.9 cm) and MYL (144.1 cm). MYL had the highest length of top-three nodes, while CJR showed the opposite. HYL had the lowest rate of panicle and neck internode to plant height and rate of neck internode to stalk length, while HYL had the highest dry weight per stem, dry weight per sheath, and dry weight per unit internode among different rice types. Breeding index on plant-type characteristics of high-yielding lines of Yongyou japonica/indica hybrid rice with medium maturity and corresponding cultivation methods were proposed.