低温冻害对不同含水量玉米种子生长发育的影响

Effect of Freezing Injury on Growth of Corn Seeds Under Different Levels of Moisture Content

以玉米杂交种富农1号、郑单958和辽单565成熟鲜果穗(籽粒含水量分别为150耀200g/kg、200耀250 g/kg、250耀300 g/kg)为材料,在0益、-5益、-10益、-15益、-20益、-25益的低温下分别处理8 h,研究了低温冻害对不同含水量玉米种子生长发育的影响。结果表明,受低温冻害的玉米种子其根数明显减少,主根长、株高、地下及地上干物质含量均显著下降。当种子含水量高于200 g/kg,温度降至0益时就会影响幼苗根数、主根长及株高;温度降至-5益时幼苗根系生长受抑,地上部分的干物质含量积累减少,生长缓慢,长势弱。种子含水量高于250 g/kg,温度降至-15益时,幼苗根系缩短变粗,出现畸形;温度降至-25益时玉米种子发芽后出现有芽无根或者有根无芽现象。

The mature fresh ears （grain moisture150-200 g/kg、200～250 g/kg250-300 g/kg） ofFunong 1, Zhengdan 958 and Liaodan 565 were used as experimental material. The growth of seedlings were studied after treating withlow temperature of 0℃、-5℃、-10℃、-15℃、-20℃、-25℃ and duration time of 8 Hrs under the given grain moisture. Theresults shows that the roots number, taproots length, plant height, underground biomass and aboveground biomass of the maizeseedlings decreased significantly after treating with different low temperature. When the grain moisture was higher than 200 g/kg and thetemperature dropped to 0 ℃, the roots number, taproots length and plant height of the seedlings would he affected harmfully; when thetemperature dropped to -5 ℃, growth of the root was bated, the accumulation of aboveground biomass reduced, seedlings growed slowlyand weakly. When the grain moisture was higher than 250 g/kg, and the temperature was lower than -15 ℃, the roots of seedlingsbecame shorter, thicker and deformity; when the temperature dropped to -25 ℃, after germination, the seeds would be no roots withbud or no bud with roots.