Influence of waterlogging on growth of pyrethrum plants infected by the crown and root rot pathogens, Fusarium oxysporum, Fusarium avenaceum and Paraphoma vinacea

The saltcedar shrub Tamarix nilotica grows as a weed in the Arava region of Israel. This weed is commonly found in cultivated fields naturally infested with Fusarium oxysporum f. sp. radicis-lycopersici, the causal agent of tomato crown and root rot. Young bushes, 20 to 40 cm tall, were randomly uprooted from different fields. The roots were cut into segments which were placed on Fusarium-selective medium. Although the plants did not show any symptoms of disease, the roots of the shrub were colonized by the pathogen. The incidence of infected saltcedar plants and level of root colonization by F. oxysporum f. sp. radicis-lycopersici decreased with increasing distance of the sampling location from a tomato field infected with crown and root rot. F. oxysporum f. sp. radicis-lycopersici was also isolated from chaff of inflorescence samples taken from mature T. nilotica shrubs. Identity of the pathogen isolates obtained from T. nilotica roots and chaff samples was verified by pathogenicity and vegetative compatibility tests. Roots of T. nilotica plants sown under greenhouse conditions in soil naturally infested with F. oxysporum f. sp. radicis-lycopersici became colonized by the pathogen. Uprooting and removing saltcedar plants throughout the season from fields not cultivated with tomatoes lowered the inoculum density of F. oxysporum f. sp. radicis-lycopersici in the soil from 611 to 6 and from 176 to 10 CFU/g of soil in the 1998-99 and 1999-2000 growing seasons, respectively. These results demonstrate that T. nilotica may contribute to the buildup of the pathogen populations in the absence of a susceptible host. Colonization of saltcedar by F. oxysporum f. sp. radicis-lycopersici is an additional mechanism for survival of this pathogen in the fields and for dissemination through the spread of infested seed or chaff of T. nilotica.

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Fusarium Oxysporum F. Sp. Radicis-Lycopersici – the Cause of Fusarium Crown and Root Rot in Tomato Cultivation

Journal of Plant Protection Research ◽

10.2478/jppr-2013-0026 ◽

2013 ◽

Vol 53 (2) ◽

pp. 172-176 ◽

Cited By ~ 11

Author(s):

Wojciech Szczechura ◽

Mirosława Staniaszek ◽

Hanna Habdas

Keyword(s):

Fusarium Oxysporum ◽

Fruit Quality ◽

Root Rot ◽

Dominant Gene ◽

Chromosome 9 ◽

Single Dominant Gene ◽

Specific Enzyme ◽

Vegetative Compatibility Groups ◽

Field Crops ◽

Crown And Root Rot

Abstract Fusarium oxysporum f. sp. radicis-lycopersici (FORL) leading to fusarium crown and root rot is one of the most destructive soilborne diseases of tomatoes occurring in greenhouse and field crops. Physiological races of FORL were not defined but nine vegetative compatibility groups (VGCs) were identified. Infection followed by wounds and natural holes and infection is not systemic. The optimum soil temperature for pathogen development is 18°C. Infection may cause plants to wilt and die completely or infection may lower fruit quality. Fusarium oxysporum f. sp. radicis-lycopersici has the ability to produce a specific enzyme, tomatinase, which breaks down α-tomatine and protects the pathogen. In contrast tomato also has a defence system which consists of the enzymes chitinase and β-1, 3-glucanase. Tomato resistance to Fusarium oxysporum f. sp. radicis-lycopersici is determined by a single dominant gene Frl, localized on the long arm of chromosome 9. It was introduced to cultivars from Licopersicum peruvianum (L.) Mill.

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Organic amendments conditions on the control of Fusarium crown and root rot of asparagus caused by three Fusarium spp.

Spanish Journal of Agricultural Research ◽

10.5424/sjar/2015134-7905 ◽

2015 ◽

Vol 13 (4) ◽

pp. e1009

Author(s):

Ana I. Borrego-Benjumea ◽

José M. Melero-Vara ◽

María J. Basallote-Ureba

Keyword(s):

Fusarium Oxysporum ◽

Incubation Period ◽

Root Rot ◽

Poultry Manure ◽

Organic Amendments ◽

Fresh Weight ◽

Fusarium Spp ◽

Lower Severity ◽

Crown And Root Rot ◽

Olive Residue

Fusarium oxysporum (Fo), F. proliferatum (Fp) and F. solani (Fs) are causal agents associated with roots of asparagus affected by crown and root rot, a disease inflicting serious losses worldwide. The propagule viability of Fusarium spp. was determined on substrate artificially infested with Fo5, Fp3 or Fs2 isolates, amended with either poultry manure (PM), its pellet (PPM), or olive residue compost (ORC) and, thereafter, incubated at 30 or 35°C for different periods. Inoculum viability was significantly affected by these organic amendments (OAs) in combination with temperature and incubation period. The greatest reduction in viability of Fo5 and Fs2 occurred with PPM and loss of viability achieved was higher at 35°C than at 30ºC, and longer incubation period (45 days). However, the viability of Fp3 did not decrease greatly in most of the treatments, as compared to the infested and un-amended control, when incubated at 30ºC. After incubation, seedlings of asparagus `Grande´ were transplanted into pots containing substrates infested with the different species of Fusarium. After three months in greenhouse, symptoms severity in roots showed highly significant decreases, but Fp3 caused lower severity than Fo5 and Fs2. Severity reduction was particularly high at 30ºC (by 15 days incubation for Fs2 and by 30-45 days for Fo5), after PPM treatment, as well as PM-2% for Fo5 and Fs2 incubated during 30 and 45 days at both temperatures, and with ORC (15-30 days incubation). Moreover, assessment of plants fresh weight showed significantly high increases in Fo5 and Fs2, with some rates of the three OAs tested, depending on incubation period and temperature.

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Inheritance of Resistance to Fusarium oxysporum f. sp. radicus-lycopersici, Causal Organism of Fusarium Crown and Root Rot in Tomato from Lycopersicon pennellii LA 1277

HortScience ◽

10.21273/hortsci.32.3.449d ◽

1997 ◽

Vol 32 (3) ◽

pp. 449D-449

Author(s):

J.W. Scott ◽

J.P. Jones

Keyword(s):

Fusarium Oxysporum ◽

Root Rot ◽

Dominant Gene ◽

Susceptible Parent ◽

Causal Organism ◽

Breeding Programs ◽

Lycopersicon Pennellii ◽

Resistant Lines ◽

Tomato Breeding ◽

Crown And Root Rot

Lycopersicon pennellii accession LA 1277 was crossed to tomato (L. esculentum) and the F1 was backcrossed to tomato. Self-pollinated seed was saved from backcross plants and seedlings derived were inoculated with Fusarium oxysporum Schlecht f.sp. radicus-lycopersici Jarvis and Shoemaker, the causal agent of Fusarium crown and root rot (FCRR). Seed was saved from resistant plants that were self-pollinated and screened until homozygous resistance was verified five generations after the backcross. Three homozygous lines were crossed to Fla. 7547, a tomato breeding line susceptible to FCRR but resistant to Fusarium wilt races 1, 2, and 3. Subsequently, backcrosses were made to each parent and F2 seed were obtained. The three homozygous FCRR-resistant lines were also crossed to Ohio 89-1, which has a dominant gene for FCRR resistance presently being used in breeding programs. F2 seed were obtained from these crosses. These generations were inoculated with the FCRR pathogen. The resistant parents, F1, and backcross to the resistant parents were all healthy. The backcross to the susceptible parent and the F2 segregated healthy to susceptible plants in 1:1 and 3:1 ratios, respectively. Thus, the resistance from LA 1277 was inherited as a single dominant gene. This gene was different than the gene from Ohio 89-1 because susceptible segregants were detected in the F2 generation derived from the two resistant sources.

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