Dwarfness in sugarcane is caused by

Efficient management of plant diseases is mainly dependent on accurate and timely detection of pathogen, severity of infection, availability of disease resistant genotypes and cost effective disease control measures. Sugarcane suffers from various fungal, viral, bacterial and phytoplasmal diseases in its crop cycle. Disease indexing in sugarcane was so far based on visual detection of symptoms and it was extremely difficult to detect the pathogen in asymptomatic plants. Recent advances in molecular biology techniques have facilitated the development of specific and sensitive, diagnostic tools for detection of pathogens of various diseases of sugarcane. PCR based detection methods are now available for red rot and smut diseases, sugarcane mosaic, yellow leaf syndrome and white leaf/grassy shoot diseases, ratoon stunting disease, leaf scald, and gumming disease to name a few. There is further need to develop highly sensitive, specific and cost effective detection tools for key pathogens, which can be used for large scale sugarcane seed certification, germplasm quarantine programmes and diagnostic laboratories in order to detect these pathogens in seed cane. Keywords • Grassy shoot • LAMP • RT-PCR • Red rot • Pathogen detection • Virus detection • Yellow leaf • Adams IP, Miano DW, Kinyua ZM, Wangai A, Kimani E, Phiri N, Reeder R, Harju V, Glover R, Hany U, Souza-Richards R, Deb Nath P, Nixon T, Fox A, Barnes A, Smith J, Skelton A, Thwaites R, Mumford R, Boonham N (2013) Use o...

Contributed equally to this work with: Shao-lin Yang, Yue-bin Zhang Roles Data curation, Formal analysis, Methodology, Writing – original draft Affiliation Yunnan Academy of Agricultural Sciences, Key Laboratory of Sugarcane Genetic Improvement, Sugarcane Research Institute, Kaiyuan, Yunnan, China • , Ratooning is an important cultivation practice in sugarcane production around the world, with underground buds on the remaining stalk acting as the source for establishment of a subsequent ratoon crop. However, the optimal depth of cutting during harvest in terms of yield and root growth remains unknown. We carried out a two-year field study to determine the effects of three cutting depths (0, 5 and 10 cm below the surface) ratoon cane root and yield. Results showed that cutting to a depth of 5 cm increased the root fresh weight and root volume by 21–59% and 41–127%, respectively, compared to cutting depths of 0 and 10 cm. Remarkably, cutting to a depth of 5 cm also had a significant effect on the development of fine roots, which is closely linked to cane yield. The effect was particularly noticeable in terms of two root traits, root volume and the surface area of roots with a diameter of 1.0–2.0mm, and root length and the number of root tips in roots with a diameter of 0–0.5mm. As a result, a cutting depth of 5 cm below the surface increased cane yield by 43 and 28% compared to depths of 0 and 10 cm below the surface, respectively. Overall, these findings suggest that a cutt...

Background Xanthomonas is a genus of gram-negative bacterium containing more than 35 species. Among these pathogenic species, Xanthomonas albilineans ( Xal) is of global interest, responsible for leaf scald disease in sugarcane. Another notable Xanthomonas species is Xanthomonas sachari ( Xsa), a sugarcane-associated agent of chlorotic streak disease. Result The virulence of 24 Xanthomonas strains was evaluated by disease index (DI) and Area Under Disease Progress Curve (AUDPC) in the susceptible inoculated plants (GT 46) and clustered into three groups of five highly potent, seven mild virulent, and twelve weak virulent strains. The highly potent strain ( X. albilineans, Xal JG43) and its weak virulent related strain ( X. sacchari, Xsa DD13) were sequenced, assembled, and annotated in the circular genomes. The genomic size of JG43 was smaller than that of DD13. Both strains (JG43 and DD13) lacked a Type III secretory system (T3SS) and T6SS. However, JG43 possessed Salmonella pathogenicity island-1 (SPI-1). More pathogen-host interaction (PHI) genes and virulent factors in 17 genomic islands (GIs) were detected in JG43, among which six were related to pathogenicity. Albicidin and a two-component system associated with virulence were also detected in JG43. Furthermore, 23 Xanthomonas strains were sequenced and classified into three categories based on Single Nucleotide Polymorphism (SNP) mutation loci and pathogenicity, using JG43 as a reference genome. Transitions were dom...

In 2019, freshly planted sugarcane setts in Vadipatti, Madurai district, a southern Indian state, exhibited sprout and shoot rot symptoms. Two fungal cultures isolated from these infected portions were identified as Athelia rolfsii based on cultural, molecular and phylogenetic analysis. The pathogenicity was confirmed both on emerging sprouts, young shoots of sugarcane, and further on tomato seedlings by the soil-inoculation method. This is the first report confirming the presence of sprout and shoot rot of sugarcane caused by Athelia rolfsii in India. • Aycock R (1966) Stem rot and other diseases caused by Sclerotium rolfsii. North Carolina, Agrl Exp St, Tech Bull, pp 174–202 • Bhuiyan SA, Wickramasinghe P, Mudge SR et al (2019) Athelia rolfsii causes sett rots and germination failure in sugarcane ( Saccharum hybrid): pathogenicity and symptomatology. Australas Plant Pathol 48(5):473–483 • Doyle JJ, Doyle JL (1987) A rapid DNA isolation procedure for small quantities of fresh leaf tissue. Phytochem Bull 19:11–15 • Gholami M, Ebrahimi A, Mozafari J et al (2020) Phenotypic and genotypic screening of common bean ( Phaseolus vulgaris L.) landraces for resistance to collar rot fungus ( Sclerotium rolfsii Sacc.) in North of Iran. J Plant Pathol 102(1):67–78 • Hall T (1999) BioEdit: a user-friendly biological sequence alignment editor and analysis program for Windows 95/98/NT. In. Nucleic Acids Symposium Series 41:95–98 • Kator L, Hosea ZY, Oche OD (2015) Sclerotium rolfsii: cau...