Plant basal resistance - Universiteit Utrecht

Chapter 5
rhizospheric signals that can recruit and select for a plant-beneficial microbes, but they can
also be exploited by specialist herbivores to locate roots of their plant hosts.
POTENTIAL OF PLANT-BENEFICIAL RHIZOBACTERIA FOR SUSTAINABLE CROP
PROTECTION
Plant disease caused by various pathogens is a cosmopolitan dilemma imposing major
constraint on food production and ecosystem stability. Plants diseases are traditionally
treated with agrochemicals. However, the use of pesticides is associated with several
negative aspects, including resistance development of the pest to the applied agent, non-
targeted environmental impacts, the carbon foot print associated with pesticide application,
and the growing cost of production, particularly in the developing world. In the developed
world, there is also an increasing consumer demand for pesticide-free food. For instance,
recent EU regulation (Regulation (EC) No 396/2005 of the European Parliament and of the
Council) on the use of agrochemicals has stimulated the search for alternative methods of
disease control. Thus, biological control has become an attractive alternative to manage
pests and diseases under the current political scenario in the EU.
Figure 3: Root colonization by P. putida KT2440 primes wild-type maize for augmented emission
of wound-inducible volatile organic compounds (VOCs). Shown are average peak values per g fresh
weight from 1-week-old plants (n = 6 ± SEM). Plants had been grown in soil supplemented with P. putida
KT2440 bacteria, as described in Chapter IV. Data were obtained by GC-MS analysis of headspace
samples, which had been entrained over a 16 h period after mock treatment, or induction treatment
by leaf damage with forceps that been dipped into a solution of 250 µM JA.
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