江西共大南城分校吕菁庚同志通过对水稻叶片的观察,发现水稻不同叶片之间叶脉数目和主脉所处位置呈规律性变化,据此可识别叶龄.水稻叶片从腹面看,有一条明显的主脉.但位置并不在正中,而是偏侧一声.一般凡属奇数叶,主脉均偏右,叶面呈左宽右狭,偶数叶则完全相反.据此可区别为奇数还是偶数叶. Through observation of rice leaves, Comrade Lu Jinggeng of Jiangxi Gongda Nancheng Branch found regular changes in the number of veins and the location of the main veins between different leaves of rice, which can be used to identify the leaf age. When viewed from the ventral aspect, But the location is not in the middle, but the side of the sound.Generally belong to the odd leaves, the main veins are right, the leaves were left and right narrow, even the opposite is the opposite .According to which can be distinguished as odd or even leaves .