Introduction 1994 1999 2002 1979 1979 1986 2001 1991 2003 1999 1991 2002 1991 1988 2002 2004 1994 10 2007 1979 2000 2000 Gossypium hirsutum G. hirsutum 15 1985 15 1 4 25 1 1992 1977 1978a 1995 5 25 15 2 3 E 1 4 2 Fig. 1 Gossypium hirsutum 1 2 E) 3 4 E) 5 6 7 8 1 9 2  Fig. 2 1  2004 Spodoptera exigua 1997 1984 1989 1996 1997 1997 2000 2005 Methods and Material Plants G. hirsutum 2 −1 −1 3 Fig. 3 Gossypium hirsutum Grid pattern Spodoptera littoralis  Herbivores Spodoptera littoralis Experiment 1 Treatment of Cotton Plants Spodoptera littoralis 1999 2002 Foliar Glands 2 2 Analysis of Monoterpenes and Sesquiterpenes n 2 4 −1 m z 1985 G. hirsutum Analysis of Terpenoid Aldehydes 1988 n 2 2 −1 15 25 1988 2004 30 Experiment 2 Spodoptera littoralis G. hirsutum. Statistics—Experiment 1 Total Foliage 2002 R Single Leaves R Statistics—Experiment 2 Single Leaves R Results Experiment 1 Terpenoid Accumulation in Total Cotton Foliage after Induction 4 H =  P =  H =  P =  H =  P <  Q =  Q =  Q P Q =  Q =  Q =  P <  Fig. 4 N  Mech Spodoptera littoralis JA Ctrl Asterisks P  1 E 1 4 4 1 2 3 Table 1 N  G. hirsutum Spodoptera littoralis Compound df Levels of terpenoids (mg) F H P Control Mechanical damage Herbivory JA Monoterpenes α-Pinene 7.213 0.065 1.11 ± 0.08 1.26 ± 0.11 1.31 ± 0.25 1.45 ± 0.44 β-Pinene 7.647 0.054 0.20 ± 0.02 0.23 ± 0.02 0.25 ± 0.05 0.26 ± 0.08 Myrcene 10.167 0.017 0.49 ± 0.06 0.68 ± 0.04 0.78** ± 0.15 0.80** ± 0.33 (E)-β-Ocimene 17.487 <0.001 0.06 ± 0.02 0.25 ± 0.06 0.47** ± 0.11 0.49** ± 0.26 Sesquiterpenes (E)-β-Caryophyllene 16.340 <0.001 0.50 ± 0.07 0.76 ± 0.12 0.95** ± 0.21 1.32** ± 0.50 α-Humulene 9.509 <0.001 0.14 ± 0.02 0.22 ± 0.03 0.27 * ± 0.06 0.36 * ± 0.13 γ-Bisabolene 18.007 <0.001 0.23 ± 0.04 0.34 ± 0.06 0.45** ± 0.10 0.60** ± 0.19 β-Bisabolol 14.340 0.002 0.46 ± 0.05 0.59 ± 0.09 0.82** ± 0.18 0.91** ± 0.26 Terpenoid aldehydes Hemigossypolone 15.287 0.002 1.59 ± 0.30 2.16 ± 0.44 3.14** ± 0.40 3.10** ± 0.83 Heliocide 1 20.487 <0.001 0.59 ± 0.14 1.65 ± 0.37 3.35** ± 1.11 5.95** ± 1.93 Heliocide 2 21.031 <0.001 0.97 ± 0.21 1.45 ± 0.42 1.83 * ± 0.37 3.06 * ± 0.74 Heliocide 3 23.938 <0.001 0.37 ± 0.07 0.56 ± 0.15 0.70 * ± 0.15 1.23 * ± 0.30 Heliocide 4 20.247 <0.001 0.17 ± 0.08 0.59 ± 0.25 1.47** ± 0.39 2.60** ± 0.78 F H *P P Growth and Subepidermal Gland Production of Cotton Foliage F P 2 2 P . t  P 5 t  P t  P Fig. 5 Mech Spodoptera littoralis Herb JA Ctrl GLM  Single Leaf Analysis 6 3 4 3 4 Fig. 6 N  Spodoptera littoralis asterisks a b c e P  6 6 6 6 2 E E 7 7 6 Fig. 7 N  Gossypium hirsutum Mech Spodoptera littoralis Herb JA Ctrl Asterisks P Pound signs P  Table 2 G. hirsutum Compound df df  df  F P F P F P Total terpenoids 37.81 <0.001 17.45 <0.001 6.78 <0.001 Monoterpenes α-Pinene 6.70 <0.001 39.98 <0.001 4.02 <0.001 β-Pinene 4.34 0.006 42.48 <0.001 3.67 <0.001 Myrcene 10.25 <0.001 51.60 <0.001 4.06 <0.001 (E)-β-Ocimene 106.72 <0.001 79.24 <0.001 6.50 <0.001 Sesquiterpenes (E)-β-Caryophyllene 24.13 <0.001 13.30 <0.001 6.59 <0.001 α-Humulene 20.56 <0.001 9.66 <0.001 3.21 <0.001 γ-Bisabolene 37.08 <0.001 11.33 <0.001 5.74 <0.001 β-Bisabolol 23.15 <0.001 12.48 <0.001 4.99 <0.001 Terpenoid aldehydes Hemigossypolone 10.16 <0.001 15.48 <0.001 6.47 <0.001 Heliocide 1 64.63 <0.001 13.78 <0.001 8.88 <0.001 Heliocide 2 27.13 <0.001 17.65 <0.001 4.94 <0.001 Heliocide 3 30.60 <0.001 17.66 <0.001 4.83 <0.001 Heliocide 4 55.70 <0.001 104.05 <0.001 8.59 <0.001 Experiment 2 Morphological and Chemical Changes in Young Leaves after Induction F  P  8 5 t  P  t P  t  P t  P  8 Fig. 8 N  Gossypium hirsutum Mech Spodoptera littoralis Herb Ctrl Asterisks a b c d P P P  F  P  F  P 8 t  P  t  P t  P Discussion G. hirsutum 10 15 15 25 30 Spodoptera littoralis S. exigua Agriotes lineatus 1997 1998 2004 1979 1987 2000 G. hirsutum 6 S. exigua 1997 2000 2005 2005 In counting the number of cotton leaf glands under a stereomicroscope, we may have overestimated the production of new glands after treatment if herbivory triggered the filling of pre-existing glands that were unpigmented (H. T. Alborn, personal communication). However, by using several microscopic techniques, we did not find any evidence for unfilled glands in the leaves analyzed. Therefore, we assume that actual or simulated herbivory does indeed induce increased numbers of glands in cotton. 1 4 2 3 Spodoptera 1997 1998 2004 2004 E 1 4 E 1 4 1978a 2 G. hirsutum E 2 3 1977 1978b S. littoralis 2005 8 5 6 1997 2005 2001 G. hirsutum 1997 1997 1997 1999 2003 1993 1998 2002 2007 1 G. hirsutum 2005 1987 1997 1997 1992 S. exigua Heliothis virescens G. hirsutum 1986 2000 Spodoptera 1996 1997 2001 1 2 H. virescens Pectinophora gossypiella 1978 1992 1997 2000 H. virescens 1988 1976 1995 2007 1993 1999 2006 2005 2007 1988 Electronic supplementary material Below is the link to the electronic supplementary material.
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