Study On The Relationship Between Rice Root Radial Oxygen Loss And Root Characteristics,Methane Emission

Significant difference was found in different rice varieties of methane emissions, planting low methane emissions is a potential mode to reduce methane emissions.Therefore, explore the mechanism of different rice varieties’methane emissions has the very vital significance for screening and breeding rice varieties in low emissions. A hydroponic culture experiment and field cultivation were carried out to study the difference between root radial oxygen loss (ROL) and rice roots basic characteristics, in which 8 early rice varieties and 8 late rice varieties were used to analys the rice roots organization affecting roots radial oxygen loss (ROL); Through field experiment monitoring paddy field methane emissions was analysed the influence of ROL of methane emissions.The results showed that:(1) Varieties of rice roots radial oxygen loss (ROL) had extremely significant differences, including by hybrid rice varieties radial oxygen loss in 1703.9～5179.8μmol-plant-1-h-1, and significantly higher than that conventional rice of 1013.2～3435.1μmol·plant-1-h-1.The highest ROL early rice varieties is zhuliangyou 4024 and xiangwanxian 45 is the lowest ROL varieties;Tyou 207 is the highest ROL and xiangwanxian 17 is the lowest ROL of late rice varieties.(2)There were significant positive correlation(P<0.01) between ROL and a-naphthylamine oxidation force, active absorption area, root number, root diameter, dry weight and root aerenchyma (including the size of structure and the aerenchyma ratio of area), the longest root length, root number, root volume and rice ROL had significant positive correlation (P< 0.05). The aerenchyma more developed, the ROL ability is stronger.(3)The methane emission of hybrid rice than conventional rice in 2.4kg-hm-2-116.3kg-hm-2. Xiangzaoxian45 is the largest methane emission and zhuliangyou4024 is the lowest emission of early rice; xiangwanxian 17 is the largest methane emission and Tyou207 is the lowest emissions of late rice.Through the correlation analysis showed that the methane emission and ROL was significantly negative correlation (P< 0.01), namely the rice ROL stronger, the paddy fields of methane emission is lower.