New Horizons in Insect Science Towards Sustainable Pest Management

Nanomaterials: A Review of Their Action and Application in Pest Management ... 121

(Dyar) do not hatch if the yolk content in the eggs
is decreased (Wellington and Maelzer 1967 ).
Similar trend of mortality was also observed
when 2nd, 3rd, and 4th instar larvae treated with
tebufenozide and halofenozide (Tables 2 and
3 ). At higher concentrations, maximum of 74.3,
66.3, and 67.5 % mortality was observed when
RH-5992 was treated on 2nd, 3rd, and 4th in-
star larvae, respectively, whereas 76.3, 71.5, and
69.00 % mortality was observed when 2nd, 3rd,
and 4th instar larvae were treated with RH-0345.
Adults’ mortalities at higher concentration were
89.30 and 92.40 % on RH-5992 and RH-0345,
respectively.
It has been reported that several insecticides
reduce Corcyra sp. infestation (Jalali et al. 2007 ).
Introduction of ecdysteroid analogues in agricul-
tural field is not usual (Jenson 2008 ). Several in-
secticides have the ability to interfere with the cu-
ticular enzymes like phenoloxidase, quinone me-
thide isomerase, and DOPA decarboxylase and
these help in cuticle sclerotization in insects
(Tsubota et al. 2010 ). The successful effect of ec-
dysteroid analogues in C. cephaplonica denoted
that these substances have tremendous effect in
the cuticular cell DNA. The modified insect pro-
toxin nucleic acid sequences can also protect the
plant host, plant cells, and seeds of plants from
insect–pest attack (Abad et al. 2004 ). Moreover,
tebufenozide and halofenozide (RH-5992; RH-
0345) can induce the feeding mechanism lead-
ing to incomplete moult and thus exhibit death of
the larvae. The fecundity of treated females was
reduced by 60 % normal value and hatchabil-
ity of laid eggs ranged 0–40 %, as compared to
96.80 % in control. Due to decrease in fecundity
and hatchability, the females treated with 80 ppm
of the two compounds produced no offspring and

suffered mortality. In some insects, the decrease

in fecundity after treatment with a mimic was

shown to be due to the derangements in the dif-

ferentiation of oogonia and follicular cells (Met-

wally et al. 1973 ; Rohdendorf and Sehnal 1972 ).

It is clear that tebufenozide and halofenozide

also act through the receptor binding mechanisms

and transactivates the expression of upregulated

genes. But, because of its persistence, the down-

regulated genes that are normally expressed in the

mild presence of 20E do not express themselves.

It has been established now that tebufenozide

(RH-5992) is a potential insecticide (Retnakaran

et al. 2001 ; Kreutzweiser et al. 2011 ). Tebufeno-

zide possesses several alkyl groups such as CH3,

n-C3H7, i-C3H7, n-C4H9, and n-C5H11 at the

para-position of the benzene ring and also pos-

sess tert-butyl group. Tebufenozide is more active

because it possesses the 1- and 2-naphthyl deriva-

tives and these are very active moieties in its struc-

ture (Nakagawa et al. 2000 ; Nakagawa 2007 ).

Other types of nanoparticles for storage pest

are nanopesticides and nanoencapsulated pesti-

cides, which are expected to reduce the volume

of application and slowdown the fast release

kinetics (Elibol et al. 2003 , Niemeyer and Doz

2001 , Leiderer and Dekorsy 2008 ). Mode of ac-

tions of nanoparticles includes destruction of

the cuticle layers, the waxy layer of the cuticle

results in the desiccation of arthropods. Since

there is no chemical alteration of the absorbed

lipids the mode of action can be described as

physisorption (Leiderer and Dekorsy 2008 ).

Stadler et al. ( 2010 ) showed that nanoalumina

can be successfully used to control stored grain

pests. Nanocarriers are designed to reduce the

volume of application and slowdown the release

kinetics of agrochemicals (Perez de Luque and

Treatment PPM Egg Second instar

larvae

Third instar

larvae

Fourth instar

larvae

Adults

5 73.5 58.1 33.7 42.5 60.5

10 77.4 68.8 51 55 65.5

20 86.2 74.3 53.8 55.7 70.8

40 89.2 75.5 61 60.6 80.6

80 98.6 76.3 71.5 69 92.4

Control 0 0 0 0 0

SEm ± 1.92 0.96 1.63 0.51 0.94

CD@5 % 2.34 2.86 4.85 1.54 2.1

Table 3 Effect of select
concentrations of RH-0345
on eggs, larvae, and adults
of C. cephalonica