An intergeneric artificial hybridization was conducted between Cunninghamia R. Br. and Cryptomeria D.Don The results are as follows:1. A considerable number of hybrid seeds shed from 76 pollinated cones were ...An intergeneric artificial hybridization was conducted between Cunninghamia R. Br. and Cryptomeria D.Don The results are as follows:1. A considerable number of hybrid seeds shed from 76 pollinated cones were empty and a total of 628 looks plump. Soft X ray radiographs showed that, still and all, a majority of the “plump" seeds were embryoless (597, 95.6%) whereas some were partially developed (17,2.7%) and only a few were really full (14, 2.2%). 2. Germination test showed that all of the radiographed hybrid seeds with fully developed embryos were germinable whereas those with partially developed embryos were ungerminable. 3. Physiologically, the growth rate of hypocotyl, the date for shedding of seed coat and spreading of cotyledons, the elongation of epicotyl, and the branching of shoot of the 11 month old seedlings showed a tendency to fall behind those of the female parent; morphologically, the 11 month old hybrid seedlings with linear leaves appeared rather short, slender and weak, whereas the seedlings of the female parents with linear_lanceolate leaves appeared rather tall, stout and strong. 4. It is considered that the hybrid may be true and the crossability reveals a close phylogenetic affinity of Cunninghamia with Cryptomeria.展开更多
Abstract： Synthetic wheats are the product of the cross between Triticum turgidum L. var. durum and T. tauschii. The 7＇. tauschii has shown excellent resistance to diseases, salinity, and drought, However, these syn...Abstract： Synthetic wheats are the product of the cross between Triticum turgidum L. var. durum and T. tauschii. The 7＇. tauschii has shown excellent resistance to diseases, salinity, and drought, However, these synthetic wheats are also carriers of genes that produce varying degrees of necrosis, which is expressed as death of tissues in the hybrids （F l） generated from crosses with other bread wheats Necrotic incompatibility is a gradual premature leaf death in certain bread wheat F1 plants and it is caused by the interaction of two genes Nel and Ne2. In this paper 40 hybridizations with T. tauschii in the genetic constitution of some of the two parents made in 2006 and 2007 are presented, and their respective F1 planted at the CEI Barrow （Chacra Experimental de Barrow）. The plants that showed necrotic incompatibility had less growth than the normal F1 at tillering. Symptoms appeared at the beginning of tillering, remaining in that state and till jointing but they never headed. Out of the 16 Argentinean commercial cultivars evaluated, seven had the Ne allele in its genetic constitution and therefore showed necrotic incompatibility, whereas nine of them did not have the NE allele and their F 1 developed normally.展开更多
文摘An intergeneric artificial hybridization was conducted between Cunninghamia R. Br. and Cryptomeria D.Don The results are as follows:1. A considerable number of hybrid seeds shed from 76 pollinated cones were empty and a total of 628 looks plump. Soft X ray radiographs showed that, still and all, a majority of the “plump" seeds were embryoless (597, 95.6%) whereas some were partially developed (17,2.7%) and only a few were really full (14, 2.2%). 2. Germination test showed that all of the radiographed hybrid seeds with fully developed embryos were germinable whereas those with partially developed embryos were ungerminable. 3. Physiologically, the growth rate of hypocotyl, the date for shedding of seed coat and spreading of cotyledons, the elongation of epicotyl, and the branching of shoot of the 11 month old seedlings showed a tendency to fall behind those of the female parent; morphologically, the 11 month old hybrid seedlings with linear leaves appeared rather short, slender and weak, whereas the seedlings of the female parents with linear_lanceolate leaves appeared rather tall, stout and strong. 4. It is considered that the hybrid may be true and the crossability reveals a close phylogenetic affinity of Cunninghamia with Cryptomeria.
文摘Abstract： Synthetic wheats are the product of the cross between Triticum turgidum L. var. durum and T. tauschii. The 7＇. tauschii has shown excellent resistance to diseases, salinity, and drought, However, these synthetic wheats are also carriers of genes that produce varying degrees of necrosis, which is expressed as death of tissues in the hybrids （F l） generated from crosses with other bread wheats Necrotic incompatibility is a gradual premature leaf death in certain bread wheat F1 plants and it is caused by the interaction of two genes Nel and Ne2. In this paper 40 hybridizations with T. tauschii in the genetic constitution of some of the two parents made in 2006 and 2007 are presented, and their respective F1 planted at the CEI Barrow （Chacra Experimental de Barrow）. The plants that showed necrotic incompatibility had less growth than the normal F1 at tillering. Symptoms appeared at the beginning of tillering, remaining in that state and till jointing but they never headed. Out of the 16 Argentinean commercial cultivars evaluated, seven had the Ne allele in its genetic constitution and therefore showed necrotic incompatibility, whereas nine of them did not have the NE allele and their F 1 developed normally.
