Lower concentrations of microelements in leaves of citrus infected with 'candidatus liberibacter asiaticus'

Yoshikuni Masaoka, Aryna Pustika, Siti Subandiyah, Akiko Okada, Eko Hanundin, Benito Purwanto, Mitsuru Okuda, Yoshihiro Okada, Akira Saito, Paul Holford, Andrew Beattie, Toru Iwanami*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

26 Citations (Scopus)

Abstract

Citrus trees affected by greening (huanglongbing, HLB) often develop symptoms that resemble those of Zn or Fe deficiency in their leaves. However, there have been few studies of mineral concentrations in infected leaves. To examine the effects of infection by 'Candidatus Liberibacter asiaticus' (the causal organism of the Asiatic form of HLB) on mineral nutrition, Citrus jambhiri (Lush.), C. reticulata cv. Siem, and C. depressa Hayata were patch-grafted with infected bark squares and grown in pots in greenhouses in Japan and Indonesia. In addition, leaves were collected from field-grown C. tankan Hayata and C. unshiu Marc. in Japan and C. reticulata cv. Siem in Indonesia, and their disease status was determined by PCR. Leaf samples were homogenized in 2-(N-morpholino) ethanesulfonic acid buffer and the concentrations of water-soluble Cu, Fe, Mn, and Zn in the macerate were determined using inductively coupled plasma atomic emission spectrometry (Japan) or atomic absorption spectrometry (Indonesia). In general, infected leaf samples had lower Fe and Zn. On average, the concentrations of Fe and Zn in infected plants were approximately half those in healthy plants. Cu was not significantly reduced by infection and Mn was occasionally lower. In C. unshiu, the concentrations of Fe and Zn were reduced before chlorosis appeared. These results suggested that the concentrations of particular elements (Fe and Zn) rather than element concentrations in general are reduced by infection by 'Candidatus Liberibacter asiaticus'.

Original languageEnglish
Pages (from-to)269-275
Number of pages7
JournalJapan Agricultural Research Quarterly
Volume45
Issue number3
Publication statusPublished - Jul 2011
Externally publishedYes

Keywords

  • Citrus depressa
  • Citrus greening
  • Huanglongbing
  • Liberibacter
  • HUANGLONGBING GREENING DISEASE
  • LIBEROBACTER-ASIATICUM
  • PCR

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