Activity of Melia volkensii (Meliaceae) Extract Against Southern ...

Activity of Melia volkensii (Meliaceae) Extract
Against Southern Green Stink Bug
(Hemiptera: Heteroptera: Pentatomidae) 1
Paula Levin Mitchell, Jennifer Butler Thielen, 2 Frederick M. Stell, 3
and Howard W. Fescemyer 4
Department of Biology, Winthrop University, Rock Hill, South Carolina 29733 USA
J. Agric. Urban Entomol. 21(3): 131–141 (July 2004)
ABSTRACT An ethanolic solution of Melia volkensii (Gürke) fruit (MVextract)
was tested against the southern green stink bug, Nezara viridula (L.),
for toxicity and antifeedant effects. Fourth instars were dipped in solutions
ranging from 1 to 50 �g/�l, and mortality was found to be concentration dependent.
At sublethal doses, those molting to adulthood exhibited significantly
greater frequencies of developmental abnormalities, including malformations
of the wings, scutellum, pronotum, legs, and antennae. In no-choice tests,
feeding adults deposited significantly fewer salivary cones on soaked soybeans
dipped in MV-extract than on control seeds. However, no significant differences
in adult feeding behavior were observed when whole pods were treated
with MV-extract. This is the first report of exposure of a heteropteran crop pest
to MV-extract; growth disruption and antifeedant effects were found to be
similar to those observed for other insects.
KEY WORDS Nezara viridula, antifeedant, toxicity, limonoid
Botanical insecticides derived from plants in the family Meliaceae have been
intensively studied in recent years as an alternative to synthetic insecticides.
Azadirachtin and other limonoids from the neem tree, Azadirachta indica A.
Juss., are effective growth regulators and feeding deterrents for a wide range of
insect species (Mordue & Blackwell 1993, Isman 1997). Extracts of plants in the
related genus Melia also show insecticidal and antifeedant activity. Chinaberry
(Melia azedarach L.) extracts have been shown to deter feeding by juvenile and
adult elm leaf beetles, Xanthogalleruca luteola (Müller) (Coleoptera: Chrysomelidae)
and reduce survivorship of larvae (Valladares et al. 1997). Fruit extracts of
M. azedarach also are effective against agromyzid leafminers and whiteflies
(Abou-Fakhr Hammad et al. 2000a,b; Banchio et al. 2003). Toosendanin, a limonoid
constituent of M. azedarach, has been commercialized in China; it is a
growth inhibitor for Ostrinia nubilalis (Hübner) (Lepidoptera: Pyralidae), an ef-
1 Accepted for publication 1 February 2005.
2 Current address: 109 Guinevere Lane, Greenville, North Carolina 27858-8629.
3 Department of the Navy, United States Marine Corps, 1 st Medical Battalion, 1 st Force Service Support
Group, P.O. Box 555657, Camp Pendleton, California 92055-5667.
4 Department of Biology, The Pennsylvania State University, University Park, Pennsylvania 16802.
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132 J. Agric. Urban Entomol. Vol. 21, No. 3 (2004)
fective repellent against Pieris brassicae (L.) (Lepidoptera: Pieridae) (Luo et al.
1995, Jimenez et al. 1997), and an oviposition deterrent for Trichoplusia ni (Hübner)
(Lepidoptera: Noctuidae) (Akhtar & Isman 2003).
Melia volkensii (Gürke), an East African tree, has been less intensively studied.
However, several bioactive triterpenoids and steroids have been isolated from
the root bark (Rogers et al. 1998a,b). Many of these compounds also are found in
extracts of dried fruit and have insecticidal activity against mosquitoes (Balan
1993, Rogers et al. 1998b). The antifeedants volkensin and salannin have been
identified from fruits (Rajab et al. 1988). Fruit extracts of M. volkensii are highly
active against locusts: in addition to antifeedant effects, nymphal growth is
slowed, motility and gregarization are impaired, sexual maturity is greatly delayed,
and high mortality occurs during molting. Insecticidal activity against
adults has also been reported (Mwangi 1982, Nasseh et al. 1993, Diop & Wilps
1997, Rembold 1997, Kabaru & Mwangi 2002).
The southern green stink bug, Nezara viridula (L.) (Hemiptera: Heteroptera:
Pentatomidae), is distributed worldwide throughout the tropics and subtropics.
Economic damage from this highly polyphagous pest occurs on a variety of crops,
including nuts, corn, cotton, grains, tomatoes, and especially pulses (McPherson
& McPherson 2000, Panizzi et al. 2000). Extracts and commercial preparations of
neem reduce feeding by N. viridula on pecan and cowpea (Seymour et al. 1995,
Abudulai et al. 2003a,b); azadirachtin also interferes with nymphal development
and reduces fecundity (Abudulai et al. 2003a, Riba et al. 2003). Research with
extracts from Melia spp. has focused primarily on chewing insects; few studies of
hemipteran pests have been reported. The research reported herein investigated
the effect of an extract of dried M. volkensii fruit (MV-extract) on development
and feeding behavior of N. viridula.
Materials and Methods
Insects. Bugs were collected from cowpea fields at the Clemson Research and
Education Center in Charleston, South Carolina, and maintained in a controlled
temperature chamber at 16:8 (L:D) h, 26 ± 1°C, and ambient (38–68%) relative
humidity. Rearing techniques were modified from Jones (1985). Adults were
housed in clear plastic shoe boxes (34.3 × 20.3 × 10.2 cm [4.3 L]) and supplied with
water, pole beans (Phaseolus vulgaris L.), raw peanuts (Arachis hypogaea L.), and
folded index cards for refuge and oviposition sites. Food was replenished weekly.
Nymphs received the same food, but were reared in 946-ml (1-qt) plastic freezer
containers. Bugs from the first laboratory-reared generation were used in all
experiments.
Toxicity testing. MV-extract was purchased from R.W. Mwangi (University
of Nairobi, Kenya). Details of the extraction procedure are given by Mwangi &
Rembold (1988) and Mwangi (1997). The powdered extract was dissolved in 60%
ethanol for application. A 60% ethanol control and five concentrations (1, 5,10,
20, and 50 �g/�l) were tested in a bioassay with three experimental replicates
performed on different days. The range of concentrations tested was based on
probit values previously obtained for Lepidoptera (Stell 1997).
Fourth instars were used in all replicates, and all treatments were made 1 d
after the molt. Nymphs were held with featherweight forceps, dipped for 1 sec in
a solution of MV-extract, and blotted on absorbent paper. Sample size was 20 per

MITCHELL et al.: Response of N. viridula to MV-Extract
concentration within a replicate. Nymphs receiving the same treatment were
housed communally in the rearing containers described previously and were
checked daily for molts and deaths. Mortality was tabulated only for days 2 and
5 after treatment, but time until death or adult molt was noted for each individual.
All surviving adults were examined for malformations, and males were
preserved.
Surviving adult females were housed individually in 460-ml (16-oz) translucent
plastic drinking cups to measure longevity, fecundity, fertility, and copulatory
activity. Each female was provided with a water wick, fresh food (a peanut
and a pole bean), and a male from the rearing colony. Cages were checked daily
for mortality, eggs, and copulations, and dead males were replaced. Egg masses
were removed, held until hatch and then counted. All stages (dipped nymphs,
surviving adults, and their eggs) were maintained in the controlled environment
described above. Values for LC 50 were determined using probit analysis (LeOra
Software 1987). Data for sublethal effects (time until adult molt, malformations,
longevity, copulation frequency, fecundity, and percentage hatch) were analyzed
with t tests, one-way ANOVA or the Kruskal–Wallis test (ProStat 1996). Treatment
means with few surviving adults and consequent small sample sizes (n

134 J. Agric. Urban Entomol. Vol. 21, No. 3 (2004)
Results and Discussion
Values for LC 50 determined from 2 and 5 d mortality were significantly different,
based on nonoverlap of confidence intervals (Table 1). Immediate lethal
effects were evident at the highest concentration (50 �g/�l). At all levels of MVextract,
many nymphs died just before or during the molt to the fifth (final
nymphal) instar as reflected by the considerably lower LC 50 value for 5-d mortality
(9.13 �g/�l). Control mortality during this period was 3%. The normal
duration of the fourth instar in N. viridula under these rearing conditions is
6–7 d; thus, only the 5-d mortality measure included ecdysis (nymphs were in
the sixth day after ecdysis to fourth instar when the 5-d mortality was recorded).
Although MV-extract has low acute toxicity, as indicated by the 2-d LC 50
(35.23 �g/�l), the disruption of the molting process leads to eventual death. For
larvae of Aedes aegypti (Diptera: Culicidae), the 2-d LC 50 for MV-extract is
50 �g/ml (0.05 �g/�l) dissolved in water (Mwangi & Rembold 1988). Clearly,
continuous exposure to the MV-extract in water is more potent than a single dip
treatment. Nonetheless, the pattern of toxicity reported for mosquitoes is similar
to our results for bugs: low concentrations were not immediately lethal, but larvae
failed to reach adulthood and 43% of larval deaths were associated with ecdysis.
Topical (ULV) application of MV-extract to Schistocerca gregaria (Orthoptera:
Acrididae) in laboratory tests (Wilps et al. 1993) and field trials (Wilps & Nasseh
1994) also resulted in mortality due to the disruption of molting.
At sublethal doses, interference with ecdysis was evident in the high percentage
of malformed individuals (Fig. 1, Table 2). Deformities of the wings and
scutellum were the most common result of MV-exposure, although malformations
of the antennae, pronotum, and legs were also observed and adults often retained
juvenile color patterns. Hind wings were shortened, thickened, or twisted. Condition
of the hemelytra varied from complete absence to short, curled, or simply
failing to close or overlap properly and lie flat against the abdomen. The scutellum
was infrequently curled under, or more commonly curled upwards, sometimes
at an angle >90°. Other scutellar deformities included notching and a lack
of symmetry; often this was accompanied by shortening and discoloration of the
pronotum. Legs failed to detach from the exuvium, resulting in missing legs, tarsi,
or tarsal claws or misshapen appendages, and occasionally antennae were missing
or shortened. Deformities of the pronotum occurred at MV-extract concentrations
�5 �g/�l; other malformations were observed at all levels tested. Overall,
Table 1. Response of N. viridula fourth instar nymphs to MV-extract
applied as 1-s dip, Rock Hill, South Carolina, 1997.
Days after
treatment n Slope ± SE a
LC 50 (95% CL)
(�g/�l) � 2
2 300 1.139 ± 0.317 35.23 (19.42–81.17) 1.88 b
5 300 0.907 ± 0.210 9.13 (3.53–17.19) 1.28 b
a Probit or logit/log10(dose).
b Nonsignificant; P > 0.05.

MITCHELL et al.: Response of N. viridula to MV-Extract
Fig. 1. Adult N. viridula showing malformation of the scutellum resulting from
exposure to MV-extract (10 �g/�l) during the fourth instar.
66.4% of all observed malformations (n � 149) were associated with the wings or
scutellum; 16.1%, 12.8%, and 4.7% involved the pronotum, legs, and antennae,
respectively.
An extract of M. volkensii also caused malformations and consequently reduced
mobility when applied to desert locust nymphs. In field trials, 58% of
survivors showed deformities of the antennae, legs, wings, and eyes (Wilps &
Nasseh 1994, Diop & Wilps 1997). Wing malformations (e.g., twisting) similar to
those reported here for N. viridula were observed in adult locusts surviving topical
MV treatments (Wilps et al. 1993). Topical application of MV-extract to immature
Coranus arenaceus (Walker) (Hemiptera: Heteroptera: Reduviidae) delayed
the imaginal molt, but no deformities of resultant adults were reported
(Peveling et al. 1994). Scutellar malformations and wing twisting identical to
those noted in our study occurred when N. viridula were exposed to Neemix, a
commercial formulation of azadirachtin (Abudulai et al. 2003a).
Other sublethal effects measured (time until adult ecdysis, longevity, reproductive
parameters) did not exhibit significant differences between MV-extract
treatments and controls. Experiments with neem have shown pronounced reductions
in fecundity for heteropterans, including N. viridula and Clavigralla scutellaris
(Westwood) (Hemiptera: Heteroptera: Coreidae) (Abudulai et al. 2003a, Riba
et al. 2003, Mitchell et al. 2004). Sublethal effects of MV-extract on fitness in
locusts have also been reported (Wilps et al. 1993, Nasseh et al. 1993). In our
study, the low number of adult survivors in several MV-extract treatments interfered
with statistical analysis; nonetheless, a trend was evident for reduced
copulations and decreased fecundity in adults exposed to 1 �g/�l of MV-extract as
juveniles (Table 2).
Antifeedant effects of MV-extract were clearly apparent when rehydrated soybeans
were provided as the test food (Table 3). Salivary deposits on control seeds
significantly exceeded those on MV-extract treatments, although no effect of concentration
was evident with the two extract levels tested. When green soybean
pods were treated, a consistent trend was evident for reduced feeding in the
presence of MV-extract but results were not significant (Table 3). This finding is
135

136 J. Agric. Urban Entomol. Vol. 21, No. 3 (2004)
Table 2. Fitness of surviving N. viridula after treatment with MV-extract at various concentrations, Rock Hill,
South Carolina, 1997.
Mean ± SE a
P value df
10 �g/�l b
5 �g/�l b
1 �g/�l b
0 �g/�l b
Variable
17.06 ± 0.79a 17.58 ± 0.88a 19.38 ± 0.93a 17.25 ± 0.85* 0.148 2, 38
16.03 ± 5.00a 56.10 ± 3.09b 85.70 ± 14.30b 84.73 ± 9.71b 0.002 3, 8
33.18 ± 4.33a 36.00 ± 9.38a 22.31 ± 4.67a 16.25 ± 6.97* 0.271 2
0.188 ± 0.06a 0.069 ± 0.03a 0.033 ± 0.02* – 0.087 19
2.27 ± 0.68a 1.08 ± 0.48a 1.14 ± 0.61a 0.50 ± 0.50* 0.200 2
72.50 ± 6.72a 74.70 ± 9.03a 57.93 ± 9.14a – 0.385 2, 32
Days to adult ecdysis c,d
% malformed adults d
Longevity (days) c,e
Copulation frequency c,f
Eggs/female/day e
% hatch d
aMeans in a row followed by the same letter are not significantly different (P > 0.05); means followed by an asterisk (*) were excluded from statistical analysis because
of low numbers of surviving adults.
bConcentration (�g/�l) of MV-powder in ethanol.
cFemales only.
dOne-way analysis of variance.
e Kruskal–Wallis test.
f t-test.

MITCHELL et al.: Response of N. viridula to MV-Extract
Table 3. Antifeedant effects on N. viridula adults of MV-extract applied to soybean pods and soaked seeds, Rock
Hill, South Carolina, 1997.
No. cones or punctures (mean ± SE) a
P value b
H b
20 �g/�l c
5 �g/�l c
0 �g/�l c
Location N
Soaked seed 37 11.00 ± 2.28a 3.18 ± 0.71b 2.78 ± 1.01b 10.63 0.05).
bKruskal–Wallis test; df � 2 for all analyses.
cConcentration of MV-powder (�g/�l) in ethanol.
137

138 J. Agric. Urban Entomol. Vol. 21, No. 3 (2004)
unexpected, because MV-extract has been shown to be a potent antifeedant when
applied to wheat seedlings fed to desert locusts (Mwangi 1982) or applied to
cabbage leaf disks in choice assays using several species of Lepidoptera and the
Mexican bean beetle, Epilachna varivestis Mulsant (Coleoptera: Coccinellidae)
(Akhtar & Isman 2004). Furthermore, extracts from the closely related neem tree
significantly reduce feeding by piercing-sucking insects, including N. viridula
(Seymour et al. 1995, Abudulai et al. 2003a, Mitchell et al. 2004). Melia volkensii
does not contain azadirachtin, the primary antifeedant component of commercial
neem formulations (Rembold 1997). However, the limonoid compound salannin,
which is known to be an active antifeedant, does occur in MV-extract (Rajab et al.
1988). Salannin is also found in M. azedarach and in methanolic and hexane
extracts of neem. These neem extracts deter feeding by C. scutellaris on green
bean pods (Mitchell et al. 2004); salannin in MV-extract would be expected to
have a similar effect on N. viridula behavior. One possible explanation is that the
longer (48-h) exposure in the pod experiments resulted in desensitization. Although
such loss of activity following repeated or continuous short-term exposure
has been shown for several antifeedants, including azadirachtin and toosendanin,
the effect is considerably more pronounced for pure compounds than for mixtures
or crude extracts (Isman 2002). Long-term exposure to M. volkensii extract does
induce habituation; when larval T. ni were reared through several instars on
cabbage foliage treated with an extract of M. volkensii, deterrence was significantly
reduced (Akhtar et al. 2003). Another possibility is that the soybean pods
may have lacked adequate coverage, as no surfactant or spreading agent was
added to our test solutions. However, addition of surfactant (0.5% Tween-20) did
not alter the performance of M. azedarach extract on cucurbit leaflets; feeding
punctures by leafminers were reduced equivalently by all solutions of extract
tested (Banchio et al. 2003). Nonetheless, our results indicate that MV-extract
has no significant deterrent effect when applied to soybean pods as an ethanol
dip. It is the pods, not the seeds within, that must be effectively protected inthe
field. A formulation of M. volkensii applied as a field spray would need to include
a surfactant or spreader to ensure effective coverage.
Recent comparisons of M. volkensii seed extract to a variety of purified allelochemical
compounds (Akhtar & Isman 2004) showed the crude MV-extract to be
the most effective growth inhibitor for all lepidopteran larvae tested (and more
potent than the pure limonoid toosendanin). Furthermore, MV-extract was a
powerful antifeedant for Mexican bean beetle and several species of Lepidoptera
(Akhtar & Isman 2004). These authors emphasize the importance of using a
variety of test species and bioassay procedures, because of interspecific differences
in sensitivity and breadth of diet; e.g., generalists and specialists may
respond differently to allelochemicals. Our results with the generalist N. viridula
are not directly comparable to the consumption-based bioassays used for
the beetle and moth larvae, but the concentrations we found effective as dips
(5–9 �g/�l) are similar to their reported DC 50 values. Despite the different mode
of feeding in N. viridula, MV-extract is an effective feeding deterrent when applied
to seeds, as well as a growth disruptor and slow-acting contact insecticide.
Extracts of the fruit and seed from M. volkensii have shown promising activity
against a variety of insect orders, and should be tested further against other
hemipteran crop pests.

MITCHELL et al.: Response of N. viridula to MV-Extract
Acknowledgment
The authors thank Richard W. Mwangi for his encouragement in pursuing research on
MV-extract, Erik Ness for bug photographs, and William C. Olson for critically reviewing
the manuscript. H.W.F. and F.M.S. thank Clemson University and its Department of Entomology
(Clemson, South Carolina) for their support at the time this research was performed.
Funding for this study was provided by the South Carolina Soybean Board (grant
#96-0586) to H.W.F. and P.L.M.
References Cited
Abou-Fakhr Hammad, E. M., N. M. Nemer & N. S. Kawar. 2000a. Efficacy of chinaberry
tree (Meliaceae) aqueous extracts and certain insecticides against the pea leafminer
(Diptera: Agromyzidae). J. Agric. Sci. 134: 413–420.
Abou-Fakhr Hammad, E. M., N. M. Nemer, Z. K. Hawi & L. T. Hanna. 2000b.
Responses of the sweetpotato whitefly, Bemisia tabaci, to the chinaberry tree (Melia
azedarach (L.) and its extracts. Ann. Appl. Biol. 137: 79–88.
Abudulai, M., B. M. Shepard & P. L. Mitchell. 2003a. Antifeedant and toxic effects of a
neem (Azadirachta indica A. Juss)-based formulation Neemix� against Nezara viridula
(L.) (Hemiptera: Pentatomidae). J. Entomol. Sci. 38: 398–408.
Abudulai, M., B. M. Shepard & A. B. Salifu. 2003b. Field evaluation of a neem
(Azadirachta indica A. Juss)-based formulation Neemix� against Nezara viridula (L.)
(Hemiptera: Pentatomidae) in cowpea. Intern. J. Pest Mng. 49: 109–113.
Akhtar, Y. & M. B. Isman. 2003. Larval exposure to oviposition deterrents alters subsequent
oviposition behavior in generalist, Trichoplusia ni, and specialist, Plutella xylostella
moths. J. Chem. Ecol. 29: 1853–1870.
Akhtar, Y. & M. B. Isman. 2004. Comparative growth inhibitory and antifeedant effects
of plant extracts and pure allelochemicals on four phytophagous insect species. J. Appl.
Entomol. 128: 32–38.
Akhtar, Y., C. H. Rankin & M. B. Isman. 2003. Decreased response to feeding deterrents
following prolonged exposure in the larvae of a generalist herbivore, Trichoplusia ni
(Leptidoptera: Noctuidae). J. Ins. Behav. 16: 811–831.
Balan, K. 1993. Das wachstum der gelbfiebermücke (Aedes aegyptii) hemmende naturstoffe
aus Melia volkensii: isolierung and charakterisierung eines neuen sekundärmetaboliten.
Ph.D. Thesis, Fakultät für Chemie und Phamazie der Ludwig-Maximilians-Universität,
München, Germany.
Banchio, E., G. Valladares, M. Defago & S. Palacios. 2003. Effects of Melia azedarach
(Meliaceae) fruit extracts on the leafminer Liriomyza huidobrensis (Diptera: Agromyzidae):
Assessment in laboratory and field experiments. Ann. Appl. Biol. 143: 187–
193.
Bowling, C. C. 1979. The stylet sheath as an indicator of feeding activity of the rice stink
bug, Oebalus pugnax. J. Econ. Entomol. 72: 259–260.
Bowling, C. C. 1980. The stylet sheath as an indicator of feeding activity by the southern
green stink bug on soybeans. J. Econ. Entomol. 73: 1–3.
Diop, B. & H. Wilps. 1997. Field trials with neem oil and Melia volkensii extracts on
Schistocerca gregaria. pp. 201–207 In: Krall, S., R. Peveling and D. Ba Diallo [Eds.] New
strategies in locust control. Birkhäuser Verlag, Basel, Switzerland. 521 pp.
Fehr, W. R., C. E. Caviness, D. T. Burmwood & J. S. Pennington. 1971. Stage of
development descriptions for soybeans, Glycine max (L.). Merrill Crop Sci. 11: 929–931.
Isman, M. B. 1997. Neem insecticides. Pesticide Outlook 8: 32–38.
Isman, M. B. 2002. Insect antifeedants. Pesticide Outlook 13: 152–157.
139

140 J. Agric. Urban Entomol. Vol. 21, No. 3 (2004)
Jimenez, A., R. Mata, R. Pereda-Miranda, J. Calderon, M. B. Isman, R. Nicol &J.T.
Arnason. 1997. Insecticidal limonoids from Swietenia humilis and Cedrela salvadorensis.
J. Chemical Ecol. 23: 1225–1234.
Jones, W. A. 1985. Nezara viridula. pp. 339–343 In Singh, S. P. and R. F. Moore [Eds.]
Handbook of insect rearing, Vol. 1. Elsevier, Amsterdam, 488 pp.
Kabaru, J. M. & R. W. Mwangi. 2002. Effect of post-treatment temperature on the insecticidal
activity of Melia volkensii (Gurke) fruit extract against the African migratory
locust Locusta migratoria (Reiche & Fairmaire). Afr. J. Sci. Technol. 3: 20–33.
LeOra Software. 1987. POLO-PC, a user’s guide to probit or logit analysis. LeOra Software,
Berkeley, California.
Luo, L.-E., J. J. A. van Loon & L. M. Schoonhoven. 1995. Behavioural and sensory
responses to some neem compounds by Pieris brassicae larvae. Physiol. Entomol. 20:
134–140.
McPherson, J. E. & R. M. McPherson. 2000. Stink bugs of economic importance in
America north of Mexico. CRC Press, Boca Raton, Florida, 253 pp.
Mitchell, P. L., R. Gupta, A. K. Singh & P. Kumar. 2004. Behavioral and developmental
effects of neem extracts on Clavigralla scutellaris (Hemiptera: Heteroptera: Coreidae)
and its egg parasitoid, Gryon fulviventre (Hymenoptera: Scelionidae). J. Econ. Entomol.
97: 916–923.
Mordue, A. J. & A. Blackwell. 1993. Azadirachtin: An update. J. Insect. Physiol. 39:
903–924.
Mwangi, R. W. 1982. Locust antifeedant activity in fruits of Melia volkensii. Ent. Exp.
Appl. 32: 277–280.
Mwangi, R. W. 1997. Studies of insecticidal activity in extract fractions of Melia volkensii.
Discov. Innov. 9: 19–24.
Mwangi, R. W. & H. Rembold. 1988. Growth-inhibiting and larval effects of Melia volkensii
extracts on Aedes aegypti larvae. Entomol. Exp. Appl. 46: 103–108.
Nasseh, O., H. Wilps, H. Rembold & S. Krall. 1993. Biologically active compounds in
Melia volkensii: larval growth inhibitor and phase modulator against the desert locust
Schistocerca gregaria (Forskal) (Orth., Cyrtacanthacrinae). J. Appl. Entomol. 116: 1–11.
Panizzi, A. R., J. E. McPherson, D. G. James, M. Javahery & R. M. McPherson. 2000.
Stink bugs (Pentatomidae). pp. 421–474 In C. W. Schaefer & A. R. Panizzi (Eds.),
Heteroptera of economic importance. CRC Press, Boca Raton, Florida, 828 pp.
Peveling, R., J. Weyrich & P. Müller. 1994. Side-effects of botanicals, insect growth
regulators and entomopathogenic fungi on epigeal non-target arthropods in locust control.
pp. 147–181 In: Krall, S. & H. Wilps [Eds.] New Trends in Locust Control. TZ-
Verlagsgesselschaft, Rossdorf, Germany, 181 pp.
ProStat. 1996. User’s Handbook. Poly Software International, Salt Lake City, Utah.
Rajab, M. S., M. D. Bentley, A. R. Alford & M. J. Mendel. 1988. A new limonoid insect
antifeedant from the fruit of Melia volkensii. J. Nat. Prod. 51: 168–171.
Rembold, H. 1997. Melia volkensii: a natural insecticide against desert locusts. pp. 185–
191 In: Krall, S., R. Peveling & D. Ba Diallo [Eds.] New Strategies in Locust Control.
Birkhäuser Verlag. Basel, Switzerland. 521 pp.
Riba, M., J. Marti & A. Sans. 2003. Influence of azadirachtin on development and reproduction
of Nezara viridula L. (Het., Pentatomidae). J. Appl. Entomol. 127: 37–41.
Rogers, L. L., L. Zeng, J. F. Kozlowski, H. Shimada, F. Q. Alali, H. A. Johnson &
J. L. McLaughlin. 1998a. New bioactive triterpenoids from Melia volkensii. J. Nat.
Prod. 61: 64–70.
Rogers, L. L., L. Zeng & J. L. McLaughlin. 1998b. New bioactive steroids from Melia
volkensii. J. Org. Chem. 63: 3781–3785.
Seymour, J., G. Bowman & M. Crouch. 1995. Effects of neem seed extract on feeding
frequency of Nezara viridula L. (Hemiptera: Pentatomidae) on pecan nuts. J. Aust.
Entomol. Soc. 34: 221–223.

MITCHELL et al.: Response of N. viridula to MV-Extract
Simmons, A. M. & K. V. Yeargan. 1988. Feeding frequency and feeding duration of the
green stink bug (Hemiptera: Pentatomidae) on soybean. J. Econ. Entomol. 81: 812–815.
Stell, F. M. 1997. Toxicity of MV-extract to some insect pests of cotton, soybean and tomato.
MS thesis, Clemson University, Clemson, South Carolina, 33 pp.
Valladares, G., M. T. Defago, S. Palacios & M. C. Carpinella. 1997. Laboratory evaluation
of Melia azedarach (Meliaceae) extracts against the elm leaf beetle (Coleoptera:
Chrysomelidae). J. Econ. Entomol. 90: 747–750.
Wilps, H. & O. Nasseh. 1994. Field tests with botanicals, mycocides, and chitin synthesis
inhibitors. pp. 51–79 In Krall, S. & H. Wilps [Eds.], New trends in locust control.
TZ-Verlagsgesselschaft, Rossdorf, Germany, 181 pp.
Wilps, H., O. Nasseh, H. Rembold & S. Krall. 1993. The effect of Melia volkensii extracts
on mortality and fitness of adult Schistocerca gregaria (Forskal) (Orth., Cyrtacanthacrinae):
investigations conducted under natural conditions in S. gregaria recession
areas in the southern Tamesna desert (Republic of Niger). J. Appl. Entomol. 116: 12–19.
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