Integration of host resistance, fungicides, and spray frequencies for managing Fusarium head blight of bread wheat under field conditions in southern Ethiopia

Aggressiveness is the most important fungal trait affecting Fusarium head blight (FHB) disease invasion and stability of host resistance. Until recently, in vitro methodologies have proved to be very useful in analyzing disease responses in barley plants to FHB infection. To update our knowledge, the variation in aggressiveness for 16 isolates of four FHB species was assessed towards two barley cultivars varying in resistance to FHB. Nine aggressiveness criteria involved in three in vitro assays were used: incubation period, latent period (LP), lesion length (of detached leaf and clip-dipping inoculations), germination rate reduction, standardized area under disease progress curve (AUDPCstandard), coleoptile length reduction of Petri-dish inoculation, and percentage of infected seedlings (of foliar-spraying and pin-point inoculations). Differences in inoculated treatment were observed on young plant parts relative to water controls. Inter and intraspecific differences in aggressiveness were observed towards barley plants as measured by LP and AUDPCstandard. Nevertheless, the other seven criteria did not differentiate FHB isolates. Results indicted that a cultivar-specific aggressiveness do not exist among barley plants and pathogens for LP and AUDPCstandard. Significant correlation coefficients were obtained between the data of LP and AUDPCstandard. Moreover, the values of LP and AUDPCstandard were significantly correlated with the data of disease incidence generated under controlled and field conditions. It seems that LP and AUDPCstandard are indicators of aggressiveness occurring in the whole plant during FHB infection. To our best knowledge, this is the first in vitro research full analyzing aggressiveness of four FHB species on barley plants. In addition, our study investigates the potential use of in vitro indices in predicting FHB data generated under controlled and field conditions.

Download Full-text

Spike architecture traits associated with type II resistance to fusarium head blight in bread wheat

Euphytica ◽

10.1007/s10681-021-02936-3 ◽

2021 ◽

Vol 217 (12) ◽

Author(s):

M. F. Franco ◽

G. A. Lori ◽

G. Cendoya ◽

M. P. Alonso ◽

J. S. Panelo ◽

...

Keyword(s):

Fusarium Head Blight ◽

Bread Wheat ◽

Type Ii ◽

Head Blight ◽

Type Ii Resistance

Download Full-text

Deoxynivalenol Detoxification in Transgenic Wheat Confers Resistance to Fusarium Head Blight and Crown Rot Diseases

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-06-18-0155-r ◽

2019 ◽

Vol 32 (5) ◽

pp. 583-592 ◽

Cited By ~ 12

Author(s):

Giulia Mandalà ◽

Silvio Tundo ◽

Sara Francesconi ◽

Federica Gevi ◽

Lello Zolla ◽

...

Keyword(s):

Transgenic Plants ◽

Durum Wheat ◽

Fusarium Head Blight ◽

Bread Wheat ◽

Virulence Factor ◽

Fusarium Species ◽

Crown Rot ◽

Uridine Diphosphate ◽

Head Blight ◽

Principal Mechanism

Fusarium diseases, including Fusarium head blight (FHB) and Fusarium crown rot (FCR), reduce crop yield and grain quality and are major agricultural problems worldwide. These diseases also affect food safety through fungal production of hazardous mycotoxins. Among these, deoxynivalenol (DON) acts as a virulence factor during pathogenesis on wheat. The principal mechanism underlying plant tolerance to DON is glycosylation by specific uridine diphosphate–dependent glucosyltransferases (UGTs), through which DON-3-β-d-glucoside (D3G) is produced. In this work, we tested whether DON detoxification by UGT could confer to wheat a broad-spectrum resistance against Fusarium graminearum and F. culmorum. These widespread Fusarium species affect different plant organs and developmental stages in the course of FHB and FCR. To assess DON-detoxification potential, we produced transgenic durum wheat plants constitutively expressing the barley HvUGT13248 and bread wheat plants expressing the same transgene in flower tissues. When challenged with F. graminearum, FHB symptoms were reduced in both types of transgenic plants, particularly during early to mid-infection stages of the infection progress. The transgenic durum wheat displayed much greater DON-to-D3G conversion ability and a considerable decrease of total DON+D3G content in flour extracts. The transgenic bread wheat exhibited a UGT dose–dependent efficacy of DON detoxification. In addition, we showed, for the first time, that DON detoxification limits FCR caused by F. culmorum. FCR symptoms were reduced throughout the experiment by nearly 50% in seedlings of transgenic plants constitutively expressing HvUGT13248. Our results demonstrate that limiting the effect of the virulence factor DON via in planta glycosylation restrains FHB and FCR development. Therefore, ability for DON detoxification can be a trait of interest for wheat breeding targeting FHB and FCR resistance.

Download Full-text