王海媛，张 坤，段里成，章起明,郭瑞鸽*

(1.江西省农业气象中心，江西 南昌 330096；2.江西农业大学 农学院，江西 南昌 330045)

不同催芽程度播种后低温对中嘉早17成苗率及生长特性的影响

王海媛1,2，张 坤1，段里成1,2，章起明1,2,郭瑞鸽1*

(1.江西省农业气象中心，江西 南昌 330096；2.江西农业大学 农学院，江西 南昌 330045)

以常规早籼稻品种中嘉早17为试验材料，采用直播水稻的2种不同催芽程度——破胸和芽谷，模拟早稻直播后5 d内遭遇不同时段长低温，研究了不同强度及时长的低温胁迫对早稻成苗率及幼苗生长特性的影响。结果表明：在低温处理下，幼苗可溶性蛋白和脯氨酸含量有不同程度的升高，水稻的成苗率、苗高、第一叶长、茎叶干重显著降低，且随温度降低和处理时间的增加，成苗率的下降程度加剧；低温对水稻生长的影响存在强度与时间的互作效应；破胸谷苗在12 ℃以上温度处理5 d后恢复生长，成苗率可达87%以上，破胸谷种的耐低温能力强于芽谷。

直播早稻；低温；催芽程度；成苗率；生长特性

Abstract： The effects of different low temperature intensities and durations within 5 days after sowing with different degrees of pregermination (husk-broken seed, and seed with bud) on the seedling-forming rate and seedling growth characteristics of early indica rice variety Zhongjiazao 17 were studied. The results showed that: under low temperature stress, the soluble protein and proline contents in rice seedlings increased to various extents, but the seedling-forming rate, seedling height, length of the first leaf, and dry weight of stems and leaves were significantly decreased, and the seedling-forming rate sharply decreased with the decrease in temperature and the increase in treatment time. The intensity and duration of low temperature stress had an interaction on the growth of rice seedlings. Recovering the growth after the husk-broken seeds were treated at over 12 ℃ for 5 days, their seedling-forming rate reached 87%. The husk-broken seeds had a stronger tolerance to low temperature than the seeds with bud.

Keywords： Directly-sown early rice; Low temperature; Degree of pregermination; Seedling-forming rate; Growth characteristics

直播栽培水稻相对于传统育秧移栽的水稻种植方式，具有省工省力、成本低，便于机械化等优势[1]，且生产等量稻谷，可比移栽稻减少8～10 kg/hm2的氮肥(纯氮)用量[2]。随着直播品种选育和直播技术的进步，近年来直播水稻面积在我国及东南亚国家逐渐增加，且将可能成为我国水稻发展中具有应用前景的一种栽培方式[3-4]。

播种期的低温是制约江西直播早稻发展的最大气象灾害，明确低温灾害对直播早稻的影响程度，确定适宜的播种期，是直播早稻首先要解决的气象问题。……