利用NaN_3诱发水稻雄性不育突变及突变体的遗传表现

以2种不同浓度(1和2mmol)的 NaN_3分别处理圭辐3号和红410的预浸种子,期望从中获得雄性不育突变。结果表明,2mmol 处理的,圭辐3号和红410的 M_2代均出现雄性不育突变体,其突变频率(按 M_1穗计)分别为0.55%和0.28%,突变体频率(按 M_2株计)分别为0.06%和0.02%。而1mmol 处理的,只有圭辐3号的 M_2代出现雄性不育突变,其突变频率和突变体频率分别为0.25%和0.05%。试验中获得的雄性不育突变体均属无花粉型,开花时花药不开裂,在人工授粉条件下结实良好,但自由授粉结实率低。遗传分析表明,其雄性不育性受一对隐性基因所控制。     

THE PRODUCTION OF FOLIC ACID BY RAT LIVER IN VITRO

The occurrence in urine and in acid-autoclaved grass and liver extracts of a substance which appears to participate in the synthesis of folic acid by rat liver in vitro is described. A similar effect is produced by synthetic xanthopterin. The effect of these materials might be accomplished by (1) catalysis of the enzymatic synthesis of folic acid; (2) the release of folic acid not liberated by takadiastase from tissue complexes; or (3) their serving as substrate material for the enzymatic synthesis of folic acid. The data presented favor the last hypothesis and suggest that xanthopterin, or a substance derived from it, may constitute a portion of the folic acid molecule. The probable involvement of compounds related to ranthopterin in the formation of hemocytopoietic substances in several animal species is discussed.