Twenty-five inbred lines, including grain and forage types from the USA and China, two hybrids, one Sorghum almum, and one Parasorghum (S. versicolor) were tested for their response to anther culture . Three nutrient media were effective in inducing anther calli from six cultivars (Xin White, TX 403-TSB, DDY Sommer Milo, TX 2779, Brawley, and Spur Federal) and one was effective for plant regeneration for one cultivar, Xin White . Averaged over media, callus induction frequency (number of calli per 100 anthers) was highest in cultivars Xin White and TX 403-TSB (6 .7 and 3 .9%, respectively) . The means of cultivars for media C17-2 and Ms-t-z-2, 4 .3 and 3 .2%, respectively, were superior to that for medium 85D3-2 (0 .1%) . Expressed as an average of the six cultivars and three media the mean calli induction frequency was 2 .6% ; however, differential responses of genotype and medium were noted . Among the 10 regeneration media tested, medium MS-d-4 containing Murashige and Skoog basal components plus 2 .0 mg/1 indole-3-acetic acid (IAA) and 2 .5 mg/l kinetin was the most effective for plant regeneration . Numbers of albino plants and calli developing only roots increased directly with callus-induction time, whereas the frequency of plant regeneration decreased . Regenerated plants had varied numbers of chromosomes in root tip cells : 10, 15, 20, 40, and 60. The 29 regenerated plants that reached maturity, however, were highly fertile and contained only 10 bivalents in pollen mother cells . Normal chromosome number and behavior for the regenerated plants suggest that induced calli originated from cells other than microspores . However, spontaneous chromosome doubling in microspore-derived haploids may occur . The appearance of albinos also implies that haploids may have been produced from anther culture .

Little information is available regarding comparative forage quality of alfalfa (Medicago sativa L.) leaves and stems of the nine germplasms from which most North American cultivars have been developed. In a greenhouse trial, forage quality of leaves and stems of the nine germplasms was compared when grown in a common environment and harvested at the same phenological stage. Germplasm sources (and representative cultivar) tested were: Indian (Sirsa #9), African (African), Peruvian (Hairy Peruvian), Flemish (DuPuits), Turkistan (Lahontan), Chilean (Kansas Common), M. varia Martin (Grimm), Ladak (Ladak), M. falcata L. (Anik). Leaves of germplasm sources differed for concentrations of neutral detergent fiber, cellulose, crude protein, true in vitro digestible dry matter, and p‐hydroxybenzaldehyde, vanillic, p‐coumaric, ferulic, and sinapic acids. Stems of germplasm sources differed for concentrations of NDF, hemicellulose, CEL, TIVDDM, and p‐hydroxybenzoic, syringic, p‐coumaric, and ferulic acids. Results indicate that alfalfa germplasm sources differ in nutritive value of leaves and stems.

The genetic control of plant regeneration from callus culture was studied in tetraploid alfalfa (Medicago sativa L .) . Seven cultivars (total 72 plants) were screened for regenerability . Ladak had the best regeneration response, in which 42% of the plants regenerated . Four regenerable plants and three nonregenerable plants were used to form 10 F, hybrids and three S, populations . Segregation ratios in the populations suggested that regenerability of alfalfa via petiole culture was under the control of two complementary genes, Rn3 and Rn4; The presence of both dominant genes was necessary for a plant to regenerate in a two-step culture system .The data also indicated that gene dosage influenced regeneration efficiency . Significant reciprocal effects demonstrated that the interaction between callus induction medium and callus regenerability was affected by cytoplasmic factor(s) .

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