DIURNAL AND DEVELOPMENTAL-CHANGES IN CANOPY GAS-EXCHANGE IN RELATION TO GROWTH IN TRANSPLANTED AND DIRECT-SEEDED FLOODED RICE
DIURNAL AND DEVELOPMENTAL-CHANGES IN CANOPY GAS-EXCHANGE IN RELATION TO GROWTH IN TRANSPLANTED AND DIRECT-SEEDED FLOODED RICE
复制标题
DOI：
10.1071/pp9900119
复制
发表时间：
1990-01-01
期刊：
影响因子：
--
通讯作者：
DORFFLING, K
中科院分区：
文献类型：
--
作者：
DINGKUHN, M;SCHNIER, HF;DORFFLING, K
在相同的种植密度和几何形状条件下，对水培水稻移栽与直接播种进行了田间试验比较。每隔7 ~ 12 d测定叶片面积指数（LAI）、植株干重和分蘖数。冠层CO2和H2O交换使用移动耗尽室系统测量，每次测量需要1-1.5分钟。冠层CO2同化速率证实了植物干物质积累。净CO2同化和夜间呼吸的日测量表明，中午/下午有轻微的下降，这取决于大气蒸气压赤字（VPD）。当LAI小于1时，冠层CO2同化的光响应在全日状态下呈现光饱和状态。LAI较高时未见光饱和现象。移栽水稻受移栽冲击后，净同化率降低，叶片扩张和分蘖延迟15天。作物发育延迟7天。直播稻在营养期生长不受抑制，成熟时生物产量和分蘖数均优于移栽稻，籽粒产量与移栽稻相当。从生长动力学和同化源库关系出发，探讨了水淹水稻直接播种增产潜力。
Transplanted and direct-seeded flooded rice were compared in a field experiment using identical planting density and geometry. Leaf area index (LAI), plant dry weight, and tiller number were determined at 7-12 d intervals from seeding to maturity. Canopy CO2 and H2O exchange were measured using a mobile depletion-chamber system which requires 1-1.5 minutes per measurement. The canopy CO2 assimilation rates confirmed the plant dry matter accumulation observed. Diurnal measurements of net CO2 assimilation and night respiration indicated a mild midday/afternoon depression that depended on the atmospheric vapour pressure deficit (VPD). Light response of canopy CO2 assimilation exhibited light saturation at full daylight when LAI was lower than 1. No light saturation was observed at higher LAI. Transplanting shock in transplanted rice reduced net assimilation rates and delayed foliage expansion and tillering by 15 days. Crop development was retarded by 7 days. Uninhibited growth of direct-seeded rice during the vegetative stage led to superior biological yield and tiller number at maturity while grain yield was equal to that of transplanted rice. Potential yield increase in direct-seeded flooded rice is discussed on the basis of growth kinetics and assimilate source/sink relationships.