耐密型玉米光合速率和光合产物转运分配研究

STUDIES ON THE PHOTOSYNTHETIC RATE AND THE TRANSPORTATION OF THE PHOTOSYNTHATE IN HIGH—DENSITY TOLERANCE TYPE OF CRON

应用^(14)C同位素示踪技术,研究耐密型玉米的光合速率和光合产物转运分配规律。结果表明,玉米光合速率在耐密型和普通型之间没有显著差异。在8～16时,光合作用强度较高,光合速率在50～70mgCO_2/dm^2·h,有午睡现象。在12～14时,叶质重增加明显,光合速率与叶质重呈正相关。穗位叶的光合物质,有80%输送给其它组织器官,其中果穗占50%～60%。掖单13比对照丹玉13平均增产18%。耐密型玉米能耐密植,增加了单位面积株穗数,从而获得高产。

The photosynthetic rate and the transportation of the photosynthate in high-density-tolerance corn were studied by useing^(14)C tracing technigue. The results indicated that, the photosynthetic rate of corn hasn't more difference between corn types. The photosynthesis was higher at 8—14 hours, and the photosynthetic rate 50—70mgCO_2/dm^2·h. The phosynthesis of corn has a noon-nap. The specific gravity of leaf was incrased within 12 14 hours in relation to the photosynthetic rate. Eighty pecent of photosynthate of leaf at ear position was transportad to other tissue and organ. The amount absorbed by ear was 50%—60%. The yield of Yiedan 13 increased 18% over Danyu13, on the average. Because the condensed planting increased the number of ears per unit area, the high density tolerant corn had higher yield.