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'CP 13‐1223' (Reg. no. CV‐204, PI 698176) sugarcane (a complex hybrid of Saccharum spp.) was released to growers in June 2020 for producing on muck soils in Florida. It was developed through a decade‐long cooperative research program between the USDA‐ARS, the University of Florida Everglades Research and Education Center, and the Florida Sugar Cane League, Inc. This cultivar resulted from a poly‐cross made at the USDA‐ARS Canal Point (CP) Sugarcane Field Station. CP 13‐1223 was released because of its high commercial recoverable sucrose (CRS) and stalk weight, and demonstrated acceptable levels of cane and sucrose yields on muck soils. CP 13‐1223 has resistance to orange rust, leaf scald, Sugarcane mosaic virus strain E, ratoon stunt disease, and smut, and moderate resistance to brown rust. Based on results from 13 harvests across replicated yield trials at five locations, CP 13‐1223 performed 29.6 and 9.5% higher in CRS and stalk weight, respectively, than the check cultivar 'CP 96‐1252'. It did not differ significantly from CP 96‐1252 in either cane yield, sucrose yield, or economic profitability. CP 13‐1223 is considered to have moderate tolerance to freezing in field tests. [ABSTRACT FROM AUTHOR]

Brown rust, caused by Puccinia melanocephala, is an important disease of sugarcane worldwide. Molecular markers for a major brown rust resistance gene, Bru1, were used to screen a total of 1,282 clones in the World Collection of Sugarcane and Related Grasses ( WCSRG) to determine the distribution and frequency of the gene in Saccharum species and related genera. Bru1 was found across all species within the Saccharum complex, but the frequency varied among species. Bru1 was more prevalent in S. robustum clones (59.1%), whereas it occurred in low frequency and exhibited the highest level of variability as determined by the presence of one or both markers (18.8%) in clones of S. spontaneum. Bru1 frequency was highest in the two secondary cultivated species, S. barberi (79.3%) and S. sinense (71.8%). The frequency of Bru1 was 26.4% and 21.0% in S. officinarum and interspecific hybrid clones, respectively. Knowledge of the distribution and frequency of Bru1 in the WCSRG will complement efforts to characterize diversity in the Saccharum complex for the expected expanded use of marker-assisted selection in the future. [ABSTRACT FROM AUTHOR]

Background: Pokkah boeng disease caused by the Fusarium species complex results in significant yield losses in sugarcane. Thus, the rapid and accurate detection and identification of the pathogen is urgently required to manage and prevent the spreading of sugarcane pokkah boeng. Methods: A total of 101 isolates were recovered from the pokkah boeng samples collected from five major sugarcane production areas in China throughout 2012 and 2013. The causal pathogen was identified by morphological observation, pathogenicity test, and phylogenetic analysis based on the fungus-conserved rDNA-ITS. Species-specific TaqMan real-time PCR and conventional PCR methods were developed for rapid and accurate detection of the causal agent of sugarcane pokkah boeng. The specificity and sensitivity of PCR assay were also evaluated on a total of 84 isolates of Fusarium from China and several isolates from other fungal pathogens of Sporisorium scitamineum and Phoma sp. and sugarcane endophyte of Acremonium sp. Result: Two Fusarium species (F. verticillioides and F. proliferatum) that caused sugarcane pokahh boeng were identified by morphological observation, pathogenicity test, and phylogenetic analysis. Species-specific TaqMan PCR and conventional PCR were designed and optimized to target their rDNA-ITS regions. The sensitivity of the TaqMan PCR was approximately 10 pg of fungal DNA input, which was 1,000-fold over conventional PCR, and successfully detected pokkah boeng in the field-grown sugarcane. Conclusions/Significance: This study was the first to identify two species, F. verticillioides and F. proliferatum, that were causal pathogens of sugarcane pokkah boeng in China. It also described the development of a species-specific PCR assay to detect and confirm these pathogens in sugarcane plants from mainland China. This method will be very useful for a broad range of research endeavors as well as the regulatory response and management of sugarcane pokkah boeng. [ABSTRACT FROM AUTHOR]