宗寿余,夏士健,张启军,吕川根

(江苏省农业科学院 粮食作物研究所,江苏 南京 210014)

不同质源不育系F1的受精率对抽穗期低温的响应

宗寿余,夏士健,张启军,吕川根

(江苏省农业科学院 粮食作物研究所,江苏 南京 210014)

用4个不同质源的籼型三系不育系与5个恢复系配成20个F1组合,以常规籼稻9311为对照,分期播种,考察了抽穗期低温对各F1受精率的影响。结果表明:在低温条件下抽穗,不同质源不育系F1的受精率差异较大;根据冷反应指数(CRI),来源于红莲型的不育系粤泰A F1的受精率对抽穗期低温最敏感,其次是来源于野败型的不育系五丰A,而来源于印水型和矮败型的不育系则较钝感;根据拟合的回归方程,当抽穗期低于22 ℃的低温累积值(CDD)>0.77 ℃·d或低温持续时间(CTD)>1.89 d时, 粤泰A F1的受精率就降到70%以下,当CDD>4.16 ℃·d或CTD>2.55 d时,五丰A F1的受精率就会大幅下降。

杂交籼稻；不育系；受精率；抽穗期；低温；响应

Abstract： Twenty indica hybrid rice F1combinations were obtained through the incomplete diallel hybridizations between 4 Cytoplasmic Male Sterile (CMS) lines and 5 restoring lines. These combinations and the conventional indica rice variety “9311” (used as the control) were sown at different times, and the effects of cool temperature at heading stage on the spikelet fertilized rate (SFR) of these F1combinations were investigated. The results indicated that: under the condition of cool temperature at heading stage, there was a great difference in SFR among F1combinations originated from different types of CMS lines. According to the cool response index (CRI), the SFR of F1combinations originated from HL-type CMS line “Yuetai A” was the most sensitive to cool temperature at heading stage, followed by the SFR of F1combinations originated from WA-type CMS line “Wufeng A”, while the SFR of F1combinations originated from YS-type and DA-type CMS lines was relatively insensitive. According to the simulated regression equations, whenCDD[accumulated cool temperature (below 22 ℃) degree·day] was more than 0.77 ℃·d or whenCTD(cool temperature continued days) was over 1.89 d at heading stage, the SFR of F1combinations from “Yuetai A” decreased to below 70%; whenCDDwas more than 4.16 ℃·d or whenCTDwas over 2.55 d, the SFR of F1combinations from “Wufeng A” declined sharply.

Keywords： Hybrid indica rice; Sterile line; Spikelet fertilized rate; Heading stage; Cool temperature; Response

三系杂交籼稻在我国南方稻区种植面积很大，为我国的粮食增产增收、保障粮食安全作出了突出的贡献。目前生产上应用的三系不育系较多,不育系的不育质源类型也较多,但应用面积较大的主要有:野败型(WA)、矮败型(DA)、红莲型(HL)、印尼水田谷质型、冈型等。丰富的不育细胞质质源极大地降低了三系杂交水稻的遗传脆弱性,但不同来源的不育细胞质质源对F1农艺性状的负效应也是显而易见的[1-3]。在生产上经常发现,不同来源的不育细胞质质源,其F1对温度的反应差异较大，例如：有些质源的早稻组合在抽穗期遇高温后结实率急剧下降[4-6]；一些晚稻……