耐旱和半多穗型玉米种质对密度的反应

Response of density to the drought-tolerant and semi-prolific line in maize

试验于1999-2000年在国际玉米小麦改良中心(CIMMYT)进行。以耐旱种质TS系列及半多 穗型种质SPL系列为材料,测试了此二类种质对密度的反应。结果表明:随密度的增加,群体前期的光 截取量增加,株高和穗位高均有增加,下部叶片的衰老时间提前,穗位叶片的叶绿素含量也降低。同时, 由于高密导致单株发育不良,根、茎倒伏率增加。密度的增加还使玉米的雌雄穗开花间隔延长,单株平 均穗数降低,进而影响到玉米的产量。在正常灌溉条件下,半多穗型种质对密度的反应优于耐旱性种质, 在干旱条件下筛选出的高世代种质在充足灌水下也表现高产。

Experiment was conducted at International maize and wheat improvement center(CIMMYT) during 1999-2000. Drought tolerant (TS series) and semi-prolific lines (SPL) maize were used to study the response of density to maize germplasm .The result showed that: as the increase of plant density, radiation interception rate increased during the early developing stage, plant high and ear high also increased, but lower leaf senescence showing earlier and the chlorophyll content of ear leaf dropped. At the same time, high density also caused mal-development and high rate of root and stem lodging, long anthesis silking interval and lower ears per plant and then low grain yield. Under normal watering condition SPL showed better adaptation to density than drought tolerant maize. Maize germplasm selected under drought condition also showed high yield under normal condition.