| 摘要 |
1479824 Production of F 1 hybrid soybean seed PFIZER Inc 26 March 1975 [29 March 1974] 12775/75 Heading AlE A process for producing F 1 hybrid soybean seeds comprises growing a first parent soybean plant population, which will yield small seeds after self-pollination, in spaced apart alternate rows with a second population, which will yield large seed if self-pollinated. The first population tends to be cross-pollinated by the second population, since self-pollination is suppressed as this first population is chosen for it characteristics of an exposed floral stigma 20, anthers 22 which shed pollen only after the flower opens, and partial male sterility, whilst the second population is chosen to have characteristics as above, except that the anthers produce more, and not less, viable pollen than normal plants. Insects cross-pollinate the first (female) population plants with pollen from the second (male) population, to yield intermediate sized F 1 hybrid seed. All the seed from the first population is collected, and separated by weight or size differences into the smallest seed, resulting from any unlikely self-pollination, which is rejected, and the rest, resulting from cross-pollination is the desired F 1 hybrid seed. The largest seed from the second, selfpollinated, population may also be collected for non-planting purposes. The first population may also contain a recessive genetic marker, absent in the second population, such as a distinctive penduncular pubescence 18 colour or petal 11, 12, 14 colour, which shows up in progeny of the smallest seed and is absent in progeny of the F 1 hybrid seed. Thus the purity of the sieved seed can be tested with respect to F 1 hybrid content, by growing a sample of the saved seed and recording the incidence of the genetic marker, possibly by using a photoelectric cell. If the incidence is unacceptably high, then further screening of the seed is done and up to 95% purity of F 1 seed can be attained. Suitable plants for the two parents are derived from plants located by examining large populations of existing varieties for each of the two sets of required characteristics and are bred by known techniques into homogenous stable strains, which may also show resistance to disease etc. Before planting seed to grow the parents,. it is inocculated with nitrogenfixing bacteria. The F 1 hybrid plants may be allowed to selfpollinate to generate seed for growing F 2 hybrid plants.
|
