Abstract A description is provided for Pseudomonas alboprecipitans . Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Setaria lutescens, S. italica and Zea mays . Goto & Starr (1971) and Tominaga (1971) report natural infection of Euchlaena mexicana in Japan, while the latter author also reports natural infection of Agropyron pubescens, Bromus catharticus, B. inermis and B. marginatus in Japan, and Hordeum vulgare and Oryza sativa in the Philippines. The following are recorded as susceptible to spray inoculation: Agropyron intermedian ?, Alopecurus pratensis, Arrhenatherum elatius, Avena sativa, Echinochloa frumentacea, Festuca elatior, Holcus lanatus, Lolium multiflorum, Poa pratensis, Phalaris arundinacea, Secale cereale, Setaria geniculata, Sorghum vulgare, S. vulgare var. sudanense, Triticum aestivum . Goto & Starr (1971) also report slight infection of Phaseolus vulgaris with wounding. DISEASE: Bacterial leaf blight and stalk rot of maize and teosinte; bacterial brown stripe of foxtail and various other grasses. On leaves and sheaths spots and streaks are produced. They vary in size and in colour from yellowish or pale brown to dark brown, depending on the host and conditions. On maize, if the stalk rot occurs it is on the upper part of the stem, often at the level where the ears are produced. The top of the plant dies and bleaches. The ears are usually sterile and sometimes become rotted. GEOGRAPHICAL DISTRIBUTION: USA (Alabama, Arkansas, Florida, Georgia, Kansas, Montana, Nebraska, Texas, Virginia), Brazil, Japan, Philippines. TRANSMISSION: Presumably transmitted mainly by wind and rain. Entry into the plant is through stomata and hydathodes and, although bacterial exudate is not seen, large numbers of bacteria can emerge on to wet leaf surfaces, especially on damaged leaves.