远缘授粉和激素处理刺激高粱的无融合生殖

1978—1981年,研究了用远缘授粉结合生物激素处理的方法对高粱远缘杂交和无融合生殖的效应.母本为0K11A等9个高粱不育系,OK11B1个保持系.远缘花粉分别取自普通小麦、扁豆、向日葵、蚕豆和水稻.使用的激素为赤霉素(GA_3),萘乙酸(NAA) ,或二者混合.授粉和处理后的母本穗大多有子房膨大.当膨大子房开始萎缩时剥开可得到一定频率的胚.在授过粉的129株高粱母本中,有53株(占授粉总数的41.1%)产生了具有萌发能力的胚.其中幼胚数在1%以上的有30株,胚产生频率最高的为10%.从膨大延续19—41天的子房中剥出直径大于2mm的胚,在培养基上都具有萌发能力.高粱品种间产生胚的能力显著不同,而OK11A和OK11B之间的差异不显著.培养基中Kinetin/IAA为4/1时有利于诱导胚直接分化.而2,4—D含量高(>2ppm)有利于诱导愈伤组织产生.仅有两个胚萌发产生的幼苗长成了正常植株.对萌发胚根尖细胞和植株花粉母细胞的细胞学鉴定,和对培养获得植株的植物学观察表明,这种胚为无融合生殖产生的单倍体胚,有些能在培养基中激素作用下自然加倍形成二倍体而长成正常植株.

STIMULATING SORGHUM APOMIXIS THROUGH DISTANT POLLINATION AND HORMONE TREATMENT

The research was conducted during 1978-1981 to study the effect of distant pollination combined with hormone treatment on sorghum distant hybridization and apomixis.Maternal plants included 9 sorghum male sterile lines and 1 maintainer line. Distant pollens were taken from wheat (Triticum aestivum L.) , hyacinth dolichos (Dolichos lahlab L.) sunflower (Helianthus annuus L.) , broadbean(Vicia faba L.)and rice (Oryza sative L.) respectively. Reagents used in the hormone treatment were gibberallin (GA3) , naphthylacetic acid (NA.A) or their mixture.After the treatments,most of the heads had expanded ovaries. Certain frequencies of embryoes were obtained when the withering ovaries were split-ted. In 129 pollinated plants, 53 produced vital embryoes, 30 of them produced embryoes over 1 % . The highest frequency was 10% . The embryoes obtained from ovaries of 19-41 days pollination had the capacity to germinate.The ability to produce embryoes varied among sorghum varieties while the difference between OK11A and OK11B was not significant.4/1 was the optimum ratio of kinetin/ IAA in the medium to inducethe direct differentiation of the embryoes while certain amoumt of 2 ,4 -D(72ppm) was conducive to callus inducing. Only two germinated embryoesgrew into the normal plants. It could be concluded by the cytological inden-tification and botanical observation that the embryoes were opomictical ones.