两种穗型粳稻不同粒位籽粒垩白性状的比较分析

选用典型的直立穗型和弯曲穗型粳稻品种为材料,对两种穗型粳稻穗上不同粒位籽粒外观品质性状的差异及其分布特点进行了研究。结果表明,粳稻品种的穗型特征与品种间的垩白粒率、垩白度和透明度高低无直接的联系。同一稻穗内的不同部位间籽粒相比,垩白粒率、垩白度基本都表现为下部>中部>上部,透明度则基本相反。同一稻穗内的不同枝梗间相比,着生在二次枝梗上籽粒的垩白粒率和垩白度相对较高,而一次枝梗上的籽粒相对较低,透明度则相反。同一枝梗间的不同着粒部位相比,一次枝梗上6个粒位的垩白粒率和垩白度第1,5,6粒位较低,第2,3位较高,二次枝梗上3个粒位的垩白粒率和垩白度第1粒位最低,第2粒位最高,透明度则相反。粳稻穗型特征与品种间外观品质的优劣并无直接联系,同一稻穗内不同籽粒间的外观品质好坏与其颖花在穗上的开花顺序有密切联系。

Comparison of Grain Chalky Characters in Different Positions between Two Type Panicles of Japonica Rice

With typical japonica cultivars with erect panicle and curved panicle as the materials,the difference in appearance qualities of rice grains and their position distributions within a panicle between two types panicle of japonica rice were researched.The results showed that panicle types of japonica rice had no direct correlation with chalky grain percentage(CGP),chalkiness degree(CD)and transparence degree(TD)in the grains between the six japonica cultivars tested.All primary branches on a panicle were divided into three parts of the upper,middle and basal.The grains were numbered as 1 to 6 on a primary branch and 1 to 3 on a secondary branch from the top to base.Generally,CGP and CD on the branches at the basal part of a panicle exhibited the greatest,at the middle part the middle,and at the upper part the least.CGP and CD for the grains on a secondary branch were greater than those on a primary branch at the same part of a panicle.TD was just the opposite.CGP and CD for the grain 1,5 and 6 on the primary branches showed the lowest,the grain 2 and 3 the highest.CGP and CD were the least for the grain 1 and the greatest for the grain 2 on a secondary branch within a panicle.Type panicle of japonica rice was not directly related to appearance qualities of cultivar.The variation in appearance qualities of different grains within a panicle was closely related to the flowering order of rice grains on the rachis branches.