Genetically female seed is sought for cannabidiol (CBD) hemp production because CBD is extracted from the flowers of female hemp plants. The production of all female seed requires masculinization of female plants to produce genetically female pollen that reliably generates female seed. Of the five female hemp genotypes that we masculinized using foliar sprays of silver thiosulfate (Abacus, Cherry Wine, Mountain Mango, Youngsim10, Wife), all genotypes produced fewer large and more irregular or misshapen pollen grains than genetically male plants. The masculinized female genotypes Wife and Cherry Wine produced pollen with germination rates similar to those of the male genotype Kentucky Sunshine. Female hemp genotypes vary in their ability to produce usable pollen that disperses well, is easily collected, and germinates as well as pollen from genetically male hemp plants.

Heat resistance of freeze-dried Bacillus subtilis spores varied in a rhythmic manner as a function of time between acidification to about pH 1.5 and freezing. A comparable rapid shift to pH 11 produced little change in resistance to heat.