Abstract: In order to explore the effects of different manure nitrogen (N) input ratios on the physiological characteristics in plant leaves and grain yield of early and late rice, this paper established a field experiment in Ningxiang county of Hunan province, and investigated the protective enzyme activities and photosynthetic characteristics of early and late rice leaves, and grain yield of early and late rice. The experiment included five different fertilization treatments: without N fertilizer input as a control (M0), chemical fertilizer (M1), 30% N of organic matter plus 70% N of chemical fertilizer (M2), 50% N of organic matter plus 50% N of chemical fertilizer (M3), and 100% N of organic matter (M4). The results showed that: The activities of superoxide dismutase (superoxide dismutase, SOD), peroxidase (peroxidase, POD) and catalase (catalase, CAT) in rice leaves of M1, M2, M3 and M4 treatments were increased when compared with M0 treatment at different main growth stages of early and late rice. Meanwhile, compared with M0 treatment, the malondialdehyde (malondialdehyde, MDA) and proline (Pro) contents in rice leaves of M1, M2, M3 and M4 treatments were decreased at different main growth stages of early and late rice, respectively. ANOV indicated that the activities of SOD, POD and CAT in leaves of rice plant with M1 and M2 treatments were significantly (P＜005) higher than that of the M0 treatment, and the MDA and Pro contents in leaves of rice plant with M1 and M2 treatments were significantly (P＜005) lower than that of the M0 treatment at different main growth stages of early and late rice, respectively. Meanwhile, the net photosynthetic rate, transpiration rate, stomatal conductance in leaves of rice plant with M1, M2, M3 and M4 treatments were significantly (P＜005) higher than that of the M0 treatment at different main growth stages of early and late rice, respectively. In 2017 and 2018, the grain yield of early rice with M1 and M2 treatments were significantly (P＜005) higher than that of the M0 treatment, and the grain yield of late rice with M1 and M4 treatments were significantly (P＜005) higher than that of the M0 treatment, respectively. Compared with M0 treatment, the grain yield of M1 and M2 treatments were increased by 2 0408 and 1 9728 kg·hm-2 in early season in 2017 and 2018, the grain yield of M1 and M4 treatments were increased by 2 1724 and 2 0060 kg·hm-2 in late season in 2017 and 2018, respectively. As a result, it was an effective way for improving protective enzyme activities and photosynthetic characteristics in leaves of rice plant by taken manure N input practices, which was the physiological mechanism to obtain higher grain yield of rice.

Key words: rice, fertilizer management, physiological characteristics, protective enzyme, yield

摘要： 为探明不同有机肥氮素占总氮投入的百分比处理对双季稻区早稻和晚稻各个生育时期植株生理特性及产量的影响，以大田定位试验为平台，系统分析了无N对照（M0）、施用化肥N（M1）、30%有机肥N（M2）、50%有机肥N（M3）、100%有机肥N（M4）5个不同施肥处理双季水稻植株叶片保护性酶活性、光合特性及产量的差异。结果表明：早稻和晚稻各个主要生育时期，M1、M2、M3和M4处理均提高了植株叶片超氧化物歧化酶（superoxide dismutase，SOD）、过氧化物酶（peroxidase，POD）和过氧化氢酶（catalase，CAT）活性，降低了丙二醛（malondialdehyde，MDA）和脯氨酸（proline，Pro）含量。其中，M1和M2处理植株叶片SOD、POD和CAT活性均显著高于M0处理，而MDA和Pro含量均显著低于M0处理。早稻和晚稻各个主要生育时期，M1、M2、M3和M4处理植株叶片净光合速率、蒸腾速率和叶片气孔导度均显著高于M0处理。2017和2018年两年的早稻产量均以M1和M2处理最高，分别比M0处理显著增加2 0408和1 9728 kg·hm-2；晚稻产量分别以M1和M4处理最高，分别比M0处理显著增加2 1724和2 0060 kg·hm-2。采取不同有机肥氮素占总氮投入百分比施肥处理均有利于提高双季水稻叶片保护性酶活性和光合特性，为水稻获得高产奠定了生理基础。

关键词: 水稻, 施肥, 生理特性, 保护性酶, 产量