PNABD246.pdf

light. PHYTOPATHOLOGY, v.55:889-894. [En] [En Abst] (REP.MB-0512)
Isolates of Pseudomonas phaseolicola from the USA and foreign countries
were separated into race 1 and race 2, on the basis of their pathogenicity on
Red Mexican UI-3 bean (Phaseolus vulgaris). Of 19 pathogenic isolates from
foreign countries, 18 belonged to race 1. Some of the dry bean varieties of
Great Northern, Pinto, Red Mexican, and Red Kidney types were resistant to race
I but all were susceptible to race 2. Most snap bean varieties grown in the USA
were susceptible, except certain Blue Lake lines which showed some tolerance to
both races. About 14% of the 1,520 PI lines of Phaseolus vulgaris tested gave
uniform hypersensitive reactions to race 1. None of these lines showed this
type of reaction to race 2; however, PI 150414, from El Salvador, contained
some plants with a high degree of tolerance. Vigna radiata, V. aconitifolius,
V. mungo, V. umbellata, and a line of V. angularis were resistant
(hypersensitive) to both races, whereas Vigna radiata, Phaseolus lathyroides,
P. coccineus, P. lunatus, P. polyanthus, P. bracteatus, P. acutifolius, and P.
polystachyus were susceptible to both races. [AS]
*0336 Schmitthenner, A.F. ; Hoitink, H.A.J. ; Kroetz, M.E. 1971. Halo
blight limits Ohio production of mung beans. OHIO REPORT, v.56(4):58-60.
[En] (REP.MB-0029)
Halo blight (Pseudomonas phaseolicola) is the most serious disease of
mungbean in Ohio. It causes yield losses of 50% or more. The only means of
control so far is by use of disease-free seed from greenhouse-grown plants. A
breeding program for developing resistant cultivars is envisaged. One
apparently resistant accession has been found and attempts are being made to
identify others. [EMS]
*0337 Schmitthenner, A.F. ; Hoitink, H.A.J. ; Kroetz, M.E. 1971. Halo
blight of mung bean incited by a new strain of Pseudomonas phaseolicola
[Abat.]. PHYTOPATHOLOGY, v.61:909. [EnJ (REP.MB-1OI4)
MEETING: Annual Meeting of the American Phytopathological Society, 63rd --
Philadelphia, PA, USA, Aug 15-19, 1971
Introduction of mungbean (Vigna radiata) has not been successful in Ohio
because of severe losses from halo blight. The pathogen isolated was similar to
both Pseudomonas phaseolicola and P. glycinea in cultural characteristics.
Mungbean isolates caused water-soaking on mungbean, red kidney bean, Fordhook
242 Lima bean, and Acme soybean, but not on other soybeans used to
differentiate P. glycinea races. None of six P. phaseolicola isolates or six P.
glycinea races caused water-soaking on mungbean. Since only the mungbean
isolates are virulent to mungbean, it is proposed that they be named the
mungbean strain of P. phaseolicola. The pathogen was introduced on seed. In
experimental plots at 11 locations in Ohio initial infection occurred in plots
of Berken, Jumbo, and Oriental cultivars from seed produced in Oklahoma. Plots
from Brazil, Peru, or Thailand seed or plots from greenhouse-produced Bemken
seed had no initial infection. Halo blight eventually developed in most
cultivars at all locations. However, at four locations, plots from greenhouse
Berken seed isolated from a source of primary inoculum remained free of halo
blight. At these four locations, Berken with halo blight (Oklahoma seed)
yielded ca. 60% less than healthy Berken (greenhouse seed). [AS]
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