Plant and Soil

, Volume 294, Issue 1, pp 277–289

Saprophytic and pathogenic behaviour of R. solani AG2-1 (ZG-5) in a soil amended with Diplotaxis tenuifolia or Brassica nigra manures and incubated at different temperatures and soil water content

  • Titiek Yulianti
  • K. Sivasithamparam
  • David W. Turner
Regular Article

DOI: 10.1007/s11104-007-9254-0

Cite this article as:
Yulianti, T., Sivasithamparam, K. & Turner, D.W. Plant Soil (2007) 294: 277. doi:10.1007/s11104-007-9254-0

Abstract

The Brassicaceae species Diplotaxis tenuifolia and Brassica nigra contain high concentrations of glucosinolates, the precursors of isothiocyanates (ITCs) that can have biofumigation effects in amended soils. In a laboratory experiment, incorporation of these plants as green manures into soil was expected to suppress Rhizoctonia solani AG2-1 (ZG5), the causal agent of damping-off in canola (Brassica napus). The manures were incorporated at 1 (1% w/w) or 5 (5% w/w) g fresh material per 100 g dry soil and incubated for 6 months at 10, 20, or 30°C and at soil water contents of 10%, 40%, or 70% of water holding capacity. R. solani survived for up to 6 months as a saprophyte in un-amended soil at all soil water contents and at 10 and 20°C. A temperature of 30°C suppressed R. solani below the level of detection in all treatments after one week. At 1% concentration, the green manures increased the colonisation of the soil by R. solani, which caused severe damping-off of canola subsequently sown in this soil treatment. Soil amendments at 1% temporarily increased soil microbial activity. The addition of B. nigra or D. tenuifolia green manure at 5% concentration suppressed the saprophytic growth of R. solani incubated at 10 or 20°C over all soil water contents and significantly increased the microbial activity at all soil temperatures and water contents. Canola sown into these pots did not succumb to damping-off. The efficiency of hydrolysis of glucosinolates in the 5% treatment in the first week of incubation ranged from 1.6% for 2-propenyl ITC, extracted from soil containing tissues of B. nigra, to 3.4% for 3-butenyl ITC extracted from soil containing tissues of D. tenuifolia. 2-propenyl ITC could not be detected after 7 d of incubation. In the longer term (weeks to months), the increase of microbial activity, caused by adding green manures at 5%, or volatiles from the green manures, most likely played a dominant role in suppressing R. solani. The impact of ITCs, if any, appears to be short-term (days).

Keywords

BiofumigationBrassicaceaeCanolaGreen manuresIsothiocyanatesMicrobial activity

Abbreviations

FDA

Fluorescein diacetate

GSL

Glucosinolate

ITC

Isothiocyanate

WHC

Water holding capacity

Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  • Titiek Yulianti
    • 1
    • 3
  • K. Sivasithamparam
    • 1
  • David W. Turner
    • 2
  1. 1.School of Earth and Geographical Sciences, Faculty of Natural and Agricultural SciencesThe University of Western AustraliaCrawleyAustralia
  2. 2.School of Plant Biology, Faculty of Natural and Agricultural SciencesThe University of Western AustraliaCrawleyAustralia
  3. 3.Research Institute for Tobacco and Fibre CropsMalangIndonesia