Higher costs associated with glyphosate tolerant (GT) compared to nonGT alfalfa (Medicago sativa L.) seed stimulates questions about reduced seeding rates in combination with the GT technology. Our objective was to determine if glyphosate herbicide in combination with GT alfalfa could improve the persistence, productivity, or forage quality when seeding alfalfa at a reduced rate. Glyphosate-tolerant alfalfa was seeded at seven locations into conventionally tilled seedbeds at rates of 6.7, 11.2, 15.7, and 20.2 kg ha -1 pure live seed (PLS) in the spring of 2006. Stand density, botanical composition, yield, and forage quality were determined for each seeding rate under three herbicide treatments: (i) glyphosate [N-(phosphonomethyl)glycine], (ii) a nonglyphosate herbicide, and (iii) no herbicide. Level of weed infestation was diff erent among locations, but there were no weed infestation × seeding rate or herbicide × seeding rate interaction. Lower seeding rates had lower plant mortality than higher seeding rates. Seeding rate had no aff ect on forage quality or weed content at any harvest. At only the fi rst harvest in the seeding year did the 6.7 kg ha -1 seeding rate produce less alfalfa forage (about 250 kg ha -1 ) than other seeding rates. In both the seeding year and year aft er seeding, using herbicides resulted in less weed and greater alfalfa yield than when no herbicide was used. Regardless of weed control treatment, seeding rates of GT alfalfa greater than 6.7 kg ha -1 did not improve weed control, alfalfa yield, total herbage (alfalfa + weeds) yield, or forage quality.Abbreviations: ADF, acid detergent fi ber; CP, crude protein; DM, dry matter; NDF, neutral detergent fi ber; PLS, pure live seed.

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A successful technique for the initiation and proliferation of shoots from epicotyl tissue of soybean, Glycine max, has been developed and is described. Fertile plants were recovered. Seeds were germinated on Murashige and Skoog medium containing 5#M benzyladenine. Explanted epicotyl sections were induced to form callus and shoots on Schenk and Hildebrandt medium containing 5.2mM monobasic ammonium phosphate, 74#M 3-aminopyridine, and 20/~M kinetin for five weeks. Shoot proliferation was maintained on N6 medium containing 1.75 mM ammonium sulfate, 2.1 nM picloram, and 0.1 #M benzyladenine. Shoots rooted on Gamborg's B5 medium without growth regulators. Shootforming cultures were maintained for 60 months. Although all varieties tested produced shoots, some variation in numbers of shoots obtained was observed.

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