Stability of Citrus tristeza virus protective isolate 'Pêra IAC' according to SSCP analysis of old and new lines of three sweet orange varieties

Abstract

RESUMOPalavras-chave adicionais: CTV, proteção cruzada, diversidade molecular, sintomatologia.

Severity and genetic diversity of Citrus tristeza virus complexes infecting ‘Pêra Bianchi’ sweet orange in Paraná, Brazil

“…The range of severity of citrus tristeza symptoms in 'Pêra Bianchi' sweet orange in different citrus growing regions of the state of Paraná has pointed to the need to further investigate the CTV complexes present in these citrus trees. Citrus trees maintained under field conditions are supposedly exposed to several inoculations of different strains of the virus by the insect vectors, and this may explain the wide variability observed among CTV isolates (Leonel et al 2015).…”

Radiographic analysis for the evaluation of polyembryony in Swingle citrumelo seeds

“…The most utilized cultivar in Brazilian citriculture is the Pera orange, which corresponds to 35.7% of the citrus trees. The predominance of this cultivar and the low diversity of rootstocks have increased the incidence of several diseases, such as citrus tristeza, citrus variegated chlorosis, citrus sudden death and huanglongbing (HLB), all of which cause great economical losses (Fadel et al, 2014;Yamamoto et al, 2014;Leonel et al, 2015). Currently, Swingle citrumelo is the most commonly used rootstock for diversification of orange groves in state of São Paulo (Pompeu Junior and Blumer, 2011).…”

“…The X-ray test has been used in seed researches since the 1950s, when Simak and Gustafsson (1953) demonstrated its potential for evaluating the quality of seeds of Pinus sylvestris L. Thus, this technique was used in genetic improvement works, allowing the detection of abnormalities in embryos and the determination of their development stage, and also in the isolation of mutant embryos of Arabidopsis thaliana (Bino et al, 1993). The technique also allowed to correlate the internal morphology of seeds with the germination or with the morphology of seedlings from several agriculture or forest species (Machado and Cicero, 2003;Oliveira et al, 2003;Pupim et al, 2008;Pinto et al, 2009;Carvalho et al, 2010;Gagliardi and Marcos-Filho, 2011;Socolowski et al, 2011;Kobori et al, 2012;Silva, et al, 2013;Rocha et al, 2014;Arruda et al, 2016).…”