Growth Response of Triticum Coleoptiles to Non-dialysable Milk Fractions

Dialysed skimmed cows' milk was shown to promote the elongationof Triticum vulgare var. ‘Yogo’ coleoptiles. Theoptimum concentration of skimmed milk was found to be one partto 200 parts distilled water. Milk dialysate was shown to inhibitelongation but after the cations were removed to have no influenceupon elongation. Gelatin, ß-lactalbumin, phosphovitin, and glycoproteinfraction IV each present at a concentration of 30 mg./100 ml.,increased coleoptile elongation about 20 per cent. when comparedto a distilled-water control. Proteose-peptone and -lactalbumincaused a slight inhibition in elongation. These results are discussed in terms of possible factors suchas bacterial contamination or adsorbed growth-promoting substancesas agents causing these effects.