scholarly journals First Report of Aphanomyces Root Rot of Sugar Beet in Nebraska and Wyoming

Plant Disease ◽  
2000 ◽  
Vol 84 (5) ◽  
pp. 596-596 ◽  
Author(s):  
R. M. Harveson
Keyword(s):  
Sugar Beet ◽  
Beta Vulgaris ◽  
Root Rot ◽  
Causal Agent ◽  
High Plains ◽  
Sugar Beets ◽  
Koch’S Postulates ◽  
First Report ◽  
Aphanomyces Cochlioides ◽  
Central High

Sugar beet (Beta vulgaris L.) plants exhibiting dull green and chlorotic foliage were first observed in a field near Dalton, NE, in late July 1999. Root symptoms included distal tip rot with internal, yellow-brown, water-soaked tissues. Isolations on MBV medium (1) consistently yielded Aphanomyces cochlioides Drechs. Water cultures produced primary zoospores that encysted at the tips of sporangiophores, followed by release of secondary zoospores within 12 h. Seedlings inoculated with zoospores began to die 2 weeks after emergence in a greenhouse. Symptoms on hypocotyls began as water-soaked lesions that turned black and thread-like. The causal agent was reisolated from infected seedlings, completing Koch's postulates. The disease was subsequently found in more than 15 separate fields, representing 5 of 11 sugar beet-growing counties in Nebraska and 1 county in Wyoming. In October, plants from the same fields were observed with stunted, distorted roots and superficial, scabby lesions associated with latent A. cochlioides infection. The pathogen could not be isolated from this stage but was confirmed by observing mature oospores within thin, stained sections under a microscope. The sections were additionally mixed with sterile potting soil and planted in the greenhouse with sugar beets. Several weeks after emergence, seedlings began to die, and the pathogen was reisolated. This represents the first report of Aphanomyces root rot and its spread in the Central High Plains. It also confirms that the described latent symptoms on sugar beet are caused by A. cochlioides. Reference: (1). W. F. Pfender et al. Plant Dis. 68:845, 1984.

First report of Aphanomyces cochlioides causing root rot of sugar beet in Turkey

2019 ◽  
Vol 39 ◽  
pp. 22
Author(s):  
M. Avan ◽  
C. Aksoy ◽  
Z. Katırcıoğlu ◽  
F. Demirci ◽  
R. Kaya
Keyword(s):  
Sugar Beet ◽  
Root Rot ◽  
First Report ◽  
Aphanomyces Cochlioides

scholarly journals Spatial Distribution of Aphanomyces cochlioides and Root Rot in Sugar Beet Fields

Plant Disease ◽  
2002 ◽  
Vol 86 (5) ◽  
pp. 547-551 ◽  
Author(s):  
Julie W. Beale ◽  
Carol E. Windels ◽  
Linda L. Kinkel
Keyword(s):  
Spatial Distribution ◽  
Sugar Beet ◽  
Root Rot ◽  
Relative Activity ◽  
Soil Samples ◽  
Collection Site ◽  
Minimum Threshold ◽  
Aphanomyces Cochlioides ◽  
Field Samples ◽  
Index Value

Spatial distribution of Aphanomyces cochlioides inoculum and disease was assessed in sugar beet fields located near Moorhead, MN and Wahpeton, ND. Soil samples were collected in June and July 1994 from two main plots (60 by 60 m) in each field. Samples were evaluated for A. cochlioides using a sugar beet seedling assay in the greenhouse to determine a root rot index value (0-to-100 scale), which served as an indirect estimate of relative activity and density of inoculum. Field evaluations of Aphanomyces root rot on sugar beet (0-to-7 scale) were made at harvest in September at each soil collection site. Greenhouse root rot index values correlated positively with field disease ratings for all plots. Variance-to-mean ratios of greenhouse root rot index values and of field disease ratings among samples within each plot were calculated to compare the spatial distribution of midseason inoculum with root rot at harvest. Ratios of greenhouse root rot indices indicated that inoculum of A. cochlioides was aggregated in the field at midseason, but root rot was uniform within plots by harvest. Wet weather in July through August was conducive to infection and development of symptoms. A uniform distribution of disease at harvest likely reflects a combination of factors, including root growth into inoculum foci, redistribution of inoculum, and inoculum densities that are spatially variable but all above some minimum threshold for infection.

First Report of Aphanomyces cochlioides on Sugar Beet in Texas

Plant Disease ◽  
1988 ◽  
Vol 72 (1) ◽  
pp. 79 ◽  
Author(s):  
C. M. Rush
Keyword(s):  
Sugar Beet ◽  
First Report ◽  
Aphanomyces Cochlioides

RHIZOPUS ROOT ROT OF SUGAR BEET

1943 ◽  
Vol 21c (8) ◽  
pp. 235-248 ◽  
Author(s):  
A. A. Hildebrand ◽  
L. W. Koch
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Sugar Beet ◽  
Root Rot ◽  
The Other ◽  
Effect Of Temperature ◽  
Experimental Plot ◽  
Optimum Growth ◽  
Causal Organism ◽  
Sugar Beets

During the summer of 1942 sugar beets growing in an experimental plot at the Harrow laboratory were destroyed by a root rot of a type that apparently has been reported only once previously on this host in North America. Wilting of the foliage first attracts attention to affected plants, the roots of which show, externally, grayish-brown discoloured areas and, internally, fairly sharply-delimited, grayish to coffee-coloured lesions, affected tissues being more or less spongy in consistency. The causal organism, found to be a wound parasite, has been identified as Rhizopus arrhizus Fischer. The effect of temperature on the growth in culture and on the pathogenicity of this fungus and of representatives of the species, R. oryzae and R. nigricans, has been studied. It has been found that R. arrhizus and R. oryzae are relatively high temperature organisms, showing optimum growth at about 34° to 36 °C., and each capable of infecting and destroying artificially injured sugar beets most rapidly between 30° and 40 °C. R. nigricans, also a wound parasite is, on the other hand, a relatively low temperature organism showing optimum growth in culture at about 24° and displaying highest infection capability at about 14° to 16 °C.

scholarly journals Methods of creating homozygous lines as breeding genotypes in sugar beet (Beta vulgaris) with apozygotic method of seed reproduction

Bioenergy ◽  
2021 ◽  
Author(s):  
M. V. Roik ◽  
N. S. Kovalchuk ◽  
O. A. Zinchenko ◽  
L. H. Fedoroshchak ◽  
V. I. Vlasiuk ◽  
...  
Keyword(s):  
Sugar Beet ◽  
Beta Vulgaris ◽  
Sugar Beets ◽  
Alloplasmic Lines ◽  
Total Percentage ◽  
A Value ◽  
Open Ground ◽  
Genome Ploidy ◽  
Selection Of

Purpose. Investigation of cytogenetic aspects of embryological processes in the culture of immature apomictic embryos, breeding genotypes of sugar beet with cytoplasmic sterility for differentiation and selection by gametophyte reduced parthenogenesis. Methods. Cytological, biotechnological, fluorescent cytophotometry, field, laboratory. Results. The cytogenetic features of genesis of immature apomictic embryos cells induced in vitro on the 12th, 20th and 22th days of development have been investigated on the basis of CMS apozygotic lines of Beta vulgaris and alloplasmic lines of wild species Beta maritime and Beta patula. Indicators of efficiency of haploid reduced parthenogenesis in vitro in alloplasmic lines significantly exceeded the best technologies in pollen-sterile lines of sugar beet from 3.79% to 6.25% and had a value of 62.2%, 24.8%, and 16.7%, respectively. Stabilization of genome ploidy to diploid was carried out in selected breeding numbers without colchicine, based on evaluation and selection of genome ploidy using software of ploidy analyzer (AP) Partec. Conclusions. The efficiency of haploid reduced parthenogenesis induction in vitro in apozygotic CMS breeding genotypes of sugar beet as affected by genetic potential of cytoplasm and taking into account the total percentage of haploids (50 units; 100 units) and myxoploids (50 units; 100 units) has been investigated. Homozygous lines were created by stabilizing the genome ploidy of haploid and myxoploid micro sprouts during III–IV passages without the use of colchicine. Technologies of rooting in the open ground for use in the breeding process of sugar beets have been improved.

scholarly journals First report of QoI resistance in Alternaria spp. infecting sugar beet (Beta vulgaris)

2017 ◽  
Vol 36 ◽  
pp. 5 ◽  
Author(s):  
N. Rosenzweig ◽  
L.E. Hanson ◽  
D. Pratt ◽  
J. Stewart ◽  
P. Somohano
Keyword(s):  
Sugar Beet ◽  
Beta Vulgaris ◽  
First Report ◽  
Qoi Resistance
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