NOVELTY - Microorganism comprising (i) a genetic modification that results in reduced or eliminated sporulation efficiency, and (ii) a genetic modification that results in reduced or eliminated pyruvate decarboxylate activity, is new. The microorganism is polyploid.    USE - The microorganism is useful for producing alcohol such as methanol, ethanol, propanol, butanol, pentanol, and hexanol, where the butanol includes 1-butanol, 2-butanol, 2-butanone, isobutanol and/or tert-butanol, where the microorganism is a yeast cell that is a member of a genus of yeast consisting of Saccharomyces, Schizosaccharomyces, Hansenula, Candida, Kluyveromyces, Yarrowia, Issatchenkia, and Pichia (all claimed), and the butanol is useful as a fuel additive, as a feedstock chemical in the plastics industry and as a food grade extractant in the food and flavor industry.    ADVANTAGE - The microorganism has improved cell viability and cell productivity, and enables efficient and economical production of the alcohol with high yield and reduced amount of by-products in an environmentally friendly manner.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a process for producing an alcohol comprising: either (a) providing the microorganism, (b) contacting the microorganism with one or more carbon substrates under conditions to produce alcohol, and (c) recovering the alcohol; or (a1) and (b1) the steps (a) and (b) as above per se, (c1) collecting the microorganism; (d) the step (c) as above per se, (e1) contacting the microorganism of step (c1) with the carbon substrates under conditions to produce alcohol, (f1) repeating steps (c1)-(e1), and (g1) optionally exposing the microorganism of step (c1) to low pH conditions; or (a2)-(b2) the steps (a1)-(d1) as above per se, (e2) exposing the microorganism of step (c2) to low pH conditions, (f2) collecting the microorganism from step (e2), (g2) contacting the microorganism of step (f2) with fermentation medium, (h2) collecting the microorganism of step (g2), (i2) contacting the microorganism with the carbon substrates under conditions to produce alcohol, and (j2) optionally repeating steps (c2)-(i2).