BNS小麦穗分化进程与其雄性不育性的表现

Spike Differentiation Process and the Male Sterility of BNS in Wheat

本研究以BNS小麦为试材,采用分期播种和春季播种试验,研究BNS不同播期的幼穗分化进程及其温光与育性的关系,旨在进一步明确BNS育性转化的穗分化敏感时期。结果表明:(1)随播期推迟,BNS二棱期至药隔期的穗分化天数和不育度均逐渐减小,且二者呈极显著正相关(r=0.940～0.942>r0.05/0.01=0.658/0.765)。10月1日～10月9日播种,穗分化天数为52～59d,不育度99%～100%。春播试验天数为19～22d,自交结实率为63%～78%。(2)BNS温度敏感期为雌雄蕊原基分化期和药隔期,日均温与不育度相关密切(r=-0.915～-0.818>r0.05/0.01=0.658/0.765),高度不育时平均温度为8.4～12.6℃。(3)BNS光照敏感期为药隔期,日均光长和总光照与不育度相关极显著(r为-0.799,-0.784,0.854,0.954>r0.05/0.01=0.658/0.765),高度不育时日均光照长度为6.6～6.8h。(4)春播试验中雌雄蕊分化期和药隔期的日均温、光(14.2～16.0℃、7～8h)高于诱导高度不育的温光条件,故表现可育。因此BNS温度敏感期为雌雄蕊原基分化至药隔期,光照敏感期为药隔期,是温敏为主的低温短日生态雄性不育小麦。

In order to further clarify the fertility alteration period of BNS, the spike differentiation process and the relationship between temperature light and sterility were studied by the means of time sowing in autumn and spring. The result showed that： （1） Along with the sowing time delay, both of the differentiation days from double ridge period to anther separation stage and sterility degree decreased gradually. The correlation was extremely significant between the differentiation days and the sterile degree with the correlation coefficients ranged from 0.940 to 0.942. When the sowing date was between October 1 and October 9, and the differentiation days ranged from 52 d to 59 d, the sterility degree was higher than 99%. Whereas if sowed in spring, the differentiation days reduced to 19~22 d with a self-seeds rate from 63% to 78%. （2） The thermo-sensitive stage of BNS was from pistil and stamen differentiation to anther differentiation stage. Correlation analysis shows that the relationship between the average temperature and the sterile degree was extremely significant. The correlation coefficients was from -0.915 to -0.818 and demonstrated that the correlation was extremely significant between the average temperature and the sterile degree. BNS was completely sterile between 8.4℃ and 12.6℃ at the stage of thermo-sensitive. （3） The photo-sensitive stage of BNS was anther differentiation stage. The result of correlation analysis showed the correlation between the light and the sterile degree at the stage of anther differentiation stage was extremely significant and the correlation coefficient was from -0.784 to 0.954. BNS showed complete male sterility between 6.6 h and 6.8 h in the photo-sensitive stage. （4） BNS sowed in spring was fertile with the temperature of 14.2~16℃ and the light length of 7~8 h which were above the critical point inducing high degree of sterility. In conclusion, BNS is a low temperature and short photo-period sensitive ecological male sterile line and the temperature played a leading role in the fertility alteration. The thermo-sensitive stage of BNS was from pistil and stamen differentiation stage to anther differentiation stage and the photo-sensitive period was anther differentiation stage.