Isolation of viable F1 seeds of some interspecific crosses by X-ray photography

Summary Some of the hybrid seeds obtained by interspecific crosses show lack of proper development of seed parts like embryo or endosperm. If such seeds are sown, no plant is usually obtained. However, if the internal details of the seeds are known prior to sowing, embryo culture method may be resorted to for the under-developed seeds and the unfortunate loss of hybrid plants may probably be avoided. The use of X-ray photography was found to be very promising and was employed to assess the internal condition of the hybrid seeds obtained from the interspecific crossing programme, viz, 1. Oryza sativa × O. officinalis, 2. Abelmoschus esculentus × A. moschatus, 3. Lycopersicum esculentum × L. pimpinellifolium and 4. Solanum melongena × S. testiculatum. The special advantages of this technique are, that a. it is possible to know the internal development of F₁ seeds without causing any damage to them; b. knowing the condition of the seed, adequate care could be provided to individual seeds as judged by the radiographs; c. it is a very quick and sure method which could be used by the geneticists and breeders in their distant crossing programmes.