Book Review

I N D U C E D R E S P O N S E S T O H E R B I V O R Y . Richard Karban and Ian T. Baldwin (1997).

University of Chicago Press. ISBN 0 226 42495 2, hardback, £35, ISBN 0 226 42496 0, paperback, £14.25.

Plants do ®ght back

As a young graduate student in the late 1970s, I ®rst became

aware of the work of Erkki Haukioja in Finland, who in a

series of elegant experiments (Haukioja & NiemelaÈ, 1977,

1979) demonstrated that damage to leaves induced a plant

response in birch, which had adverse effects on larvae of the

autumnal moth Epirrita autumnata that subsequently fed on

the trees. This interesting, if not apparently world shattering,

work induced a response in the scienti®c community that

earlier work on the wood boring wasp Sirex noctilio (Coutts &

Dolezal, 1966) and the sycamore aphid Drepanosiphum

platanoidis (Dixon, 1970) had failed to do. This may have

been because Haukioja postulated that induced responses had

signi®cant effects on the population cycles of herbivores

(Haukioja & Hakala, 1975). The newly discovered ®eld proved

a fertile ground for vigorous scienti®c debate, and resulted in

what at the time seemed a very fanciful notion, the concept of

talking trees (Rhoades, 1983).

The ®eld has continued to develop and has become a ®rmly

established feature in mainstream ecology, examples being

drawn from agriculture, forestry, and horticulture as well as

from unmanipulated habitats. More recently (Hatcher et al.,

1994), the in¯uence of induced responses has also been

demonstrated in multitrophic interactions.

So much for the ®eld ± what about the book? Drs Karban

and Baldwin are to be congratulated on providing us with a

text that is both informative and readable. It is a book that

should be readily accessible to all ecologists, from under-

graduates to senior Professors. In fact, this is the perfect

example for anyone wishing to run a course on scienti®c book

writing.

The authors use the ®rst chapter to set the ®eld and introduce

us to the concept of plant defences. The historical survey is

particularly informative and, apart from the omission of the

Coutts and Dixon references mentioned earlier, has done full

justice to the literature.

The second chapter looks at how plants perceive damage and

how the signals received can be passed on to other parts of the

same plant or to other individuals of the same species. The work

cited in this chapter greatly strengthens the case for the once

ridiculed (Fowler & Lawton, 1984) concept of talking trees.

The third chapter reviews the mechanisms involved in

generating induced responses in great depth, giving an

excellent overview of the chemical processes and pathways.

This is followed by yet another excellent chapter on the effects

of induced resistance against herbivores, which asks the very

important question: Does induced resistance affect herbivore

populations? I found the evidence compelling, but as I had

planned to write a review article supporting this thesis myself

(now shelved of course!) I may be biased. The authors, and this

is typical of their approach throughout the book, present a

balanced and well-argued case for a not proven verdict.

The penultimate chapter examines the evolution of induced

resistance in plants, covering the accepted and controversial

aspects of the debate. The scholarly discussion on the costs of

such responses was particularly compelling. The ®nal chapter

is exemplary. It ®rst, and this will please my father ± a plant

pathologist, points out that plant pathologists have been aware

of the phenomenon of induced resistance for almost a century!

Secondly, it addresses the question of how what seems an

ecological curiosity can be used to increase crop production.

The prospects appear very promising.

The authors have done an excellent job in presenting the

controversial subject of induced responses to herbivory to a

wide audience, in a well balanced and intelligent manner. I was

particularly taken with the way in which the last four chapters

end with a discussion of future prospects. Too often, the

concluding sections of book chapters are trite and tired

statements of the obvious. Karban and Baldwin present

perceptive visions of the future that will almost certainly

stimulate the research directions of many of us in the ®eld.

This is a book that I have already recommended to my

graduate students and one that I would dearly like to have

written myself. Books such as these can only be stimulating. If

you have not already bought it for your own bookshelves, then

do so now. It is well worth the money.

References

Coutts, M.P. & Dolezal, J.E. (1966) Polyphenols and resin in the

resistance mechanism of Pinus radiata attacked by the woodwasp,

Sirex noctilio, and its associated fungus. Lea¯et Commonwealth

Forestry and Timber Bureau, 101, 10±19.

Dixon, A.F.G. (1970) Stabilization of aphid populations by an aphid

induced plant factor. Nature, 227, 1368±1369.

Fowler, V. & Lawton, J.H. (1984) Trees don't talk: do they even

murmur? Antenna, 8, 69±71.

Hatcher, P.E., Paul, N.D., Ayres, P.G. & Whittaker, J.B. (1994) The

effect of a foliar disease (rust) on the development of Gastrophysa

viridula (Coleoptera: Chrysomelidae). Ecological Entomology, 19,

349±360.

Haukioja, E. & Hakala, T. (1975) Herbivore cycles and periodic

outbreaks: formulation of a general hypothesis. Reports from the

Kevo Subarctic Research Station, 12, 1±9.

Haukioja, E. & NiemelaÈ, P. (1977) Retarded growth of a geometrid

L

122 # 1999 Blackwell Science Ltd

Ecological Entomology (1999) 24, 122±123Ecological Entomology (1999) 24, 122±123

larva after mechanical damage to leaves of its host tree. Annales

Zoologici Fennici, 14, 48±52.

Haukioja, E. & NiemelaÈ, P. (1979) Birch leaves as a resource for

herbivores: seasonal occurrence of increased resistance in foliage

after mechanical damage of adjacent leaves. Oecologia, 39, 151±

159.

Rhoades, D.F. (1983) Responses of alder and willow to attack by tent

caterpillars and webworms: evidence for pheromonal sensitivity of

willows. Plant Resistance to Insects (ed. by P. A. Hedin), pp. 55±68.

Symposium Series 208, American Chemical Society, Washington,

DC.

SIMON R. LEATHER

R

# 1999 Blackwell Science Ltd, Ecological Entomology, 24, 122±123

Book Review 123Book Review 123