摘要:
A method is presented which permits the induction and screening of variant plants which display a Non-Mendelian mode of inheritance. The process involves maintaining plant tissue in culture for a limited period of time in the presence of unusually high levels of growth regulators and screening regenerated plants recovered therefrom. Novel varities resulting from the process of the invention are described.
摘要:
7.beta.-Acylamino-3-trifluoromethylsulfonyloxy-1-carba-3-cephem-4-carboxylic acid antibiotic compounds, esters and salts thereof, and the corresponding 7-amino and protected 7-amino 1-carbacephalosporins are provided. The 3-trifluoromethylsulfonyloxy-substituted 1-carbacephalosporins also are useful in a process for preparing 3-halo-1-carbacephalosporins which comprises reacting a 3-triflate ester with a lithium halide in an aprotic polar solvent.
摘要:
This invention provides a method for high frequency plant regeneration from somatic stem donor tissue of field grown Zea diploperennis, a diploid, perennial corn ancestor with high tillering capacity. This species is used as a parent in a maize improvement strategy to transfer the unique traits of high tillering and plantlet regeneration capacity into cultivated corn. After 3-4 subcultures of cultured somatic tissues on a primary medium, small callus fragments are transferred to a secondary medium devoid of the auxin, 2,4-D. After a few days, numerous shoots regenerate and develop into normal plantlets which are then separated and transferred to a tertiary medium for root development. The selection of somaclonal variants form cultured somatic cells of interspecific hybrids between corn and teosinte are used for the synthesis of unique breeding lines suited for development of improved corn varieties. A protocol for gene transfer employing recombinant DNA techniques is also described.
摘要:
A method is provided of producing variant plant varieties of Lycopersicon spp. by tissue culture techniques employing 6-benzyladenine at high concentrations. The technique produces phenotypic variants that are the result of heritable nuclear genetic changes.
摘要:
7.beta.-Acylamino-3-trifluoromethylsulfonyloxy-1-carba-3-cephem-4-carboxylic acid antibiotic compounds, esters and salts thereof, and the corresponding 7-amino and protected 7-amino 1-carbacephalosporins are provided. The 3-trifluoromethylsulfonyloxy-substituted 1-carbacephalosporins also are useful in a process for preparing 3-halo-1-carbacephalosporins which comprises reacting a 3-triflate ester with a lithium halide in an aprotic polar solvent.
摘要:
This invention provides a method for high frequency plant regeneration from somatic stem donor tissue of field grown Zea diploperennis, a diploid, perennial corn ancestor with high tillering capacity. This species is used as a parent in a maize improvement strategy to transfer the unique traits of high tillering and plantlet regeneration capacity into cultivated corn. After 3-4 subcultures of cultured somatic tissues on a primary medium, small callus fragments are transferred to secondary medium devoid of the auxin, 2,4-D. After a few days, numerous shoots regenerate and develop into normal plantlets which are then separated and transferred to a tertiary medium for root development. The selection of somaclonal variants form cultured somatic cells of interspecific hybrids between corn and teosinte are used for the synthesis of unique breeding lines suited for development of improved corn varieties. A protocol for gene transfer employing recombinant DNA techniques is also described.
摘要:
A bucket wheel for a bucket wheel unloader has a series of buckets mounted on pivots around its periphery so that the buckets can be displaced between opposite end positions to correspond with either direction of rotation of the wheel. Latching means engage the buckets to retain them in their required end positions and operate automatically when the direction of rotation of the wheel is reversed.
摘要:
The novel synthesis of chemical compounds of the structures 1 and 2 is disclosed. ##STR1## wherein R.sub.1 is a member of the group consisting of alkyl, (cis or trans) alkenyl and alkynyl groups of from 2 to 9 carbon atoms which can be substituted by a terminal 1,3-dioxyacyclopentyl, a carboxyl or a carboalkoxy (--COOR') group where R' is an alkyl group of 1 to 6 carbon atoms. Compounds 1 and 2 are shown to be useful intermediates in prostaglandin synthesis.
摘要:
The novel synthesis of chemical compounds of the structures 1 and 2 is disclosed. ##STR1## Compounds 1 and 2 are shown to be useful intermediates in prostaglandin synthesis.