Insects of stored rice in Portugal: fungus-feeders, commodity-feeders and beneficials

Abstract

Studies were conducted in seven producer owned paddy rice warehouses and one silo in addition to one rice mill, from November 2002 to date. The studies were undertaken in order to determine the insect species associated with stored rice and their abundance, using several sampling methods. From the results, for farm storage it may be considered that moisture content may be the major factor that affects paddy storage allowing fungal production while at the rice mill the main insects caught were commodity-feeders The most abundant species was C. ferrugineus followed by Sitophilus spp. (S. oryzae and mainly S. zeamais). Predators and parasitoids were recorded and the parasitoids, associated with the main pests,were the majority. The existence of natural enemies may encourage studies of using them in a program of biological control.

Full text

Carvalho M. O, Barbosa A., Magro A., Timlick B., Adler C., Marques, P., Teixeira, A.,
Jesus O., Mexia A (2005). Insects of stored rice in Portugal: fungus-feeders,
commodity-feeders and beneficials. Proceedings of Meeting of Working Group 4,
COST 842, Barcelona, Spain, October 28-29, 2004: 11-15.
1
Insects of stored rice in Portugal: fungus-feeders,
commodity-feeders and beneficials
Maria Otilia Carvalho
1*
; António Barbosa
1
; Ana Magro
1
; Blaine Timlick
2
; Cornel
Adler
3
; Pedro Marques
4
; Altino Teixeira
5
; Otília Jesus
5
; António Mexia
1
1
Tropical Scientific Research Institute, Lisbon, Portugal;
2
CGC, Winnipeg, Canada;
3
BBA, Berlin,
Germany;
4
Aparroz -Rice Farmers Association from Sado Valey, Portugal;
5
Sear - Rice European
Society, Santiago do Cacém, Portugal;
1*
motiliac@netcabo.pt
Abstract
Studies were conducted in seven producer owned paddy rice warehouses and one silo in
addition to one rice mill, from November 2002 to date. The studies were undertaken in order
to determine the insect species associated with stored rice and their abundance, using several
sampling methods.
From the results, for farm storage it may be considered that moisture content may be the
major factor that affects paddy storage allowing fungal production while at the rice mill the
main insects caught were commodity-feeders The most abundant species was C. ferrugineus
followed by Sitophilus spp. (S. oryzae and mainly S. zeamais). Predators and parasitoids
were recorded and the parasitoids, associated with the main pests,were the majority. The
existence of natural enemies may encourage studies of using them in a program of biological
control.
Key-words: paddy rice, trap, stored product insect
Introduction
Portugal is the biggest consumer of white rice in Europe. The annual paddy production in
Portugal is about 129,000 tonnes of japonica rice (short-grain) and 26,000 tonnes of indica
rice (long-grain) distributed into three main regions: Sado Valley (43,400 tonnes japonica
rice and 19,500 tonnes indica rice); Tejo Valley (49,600 tonnes japonica rice and 6,500
tonnes indica rice); and Mondego Valley (36,000 tonnes japonica rice). Two thousand rice
farmers and 12 rice mills are involved in this production.
Paddy is a seasonal crop in Portugal and, as a consequence, the storage of paddy and milled
rice is very important for year round availability. Since November 2002, studies were
developed in paddy storage systems on farms and in a rice mill in order to evaluate storage
conditions, the main causes of rice storage loss and to assist in the development of integrated
pest management strategies.
The main causes of loss in paddy and milled rice storage are due to insect pests and moisture.
After harvest, paddy is dried to 12-13% moisture content and is then stored. If little is done
to manage the grain storage on the farm, moisture content and fungi development will likely
occur due to moisture content increases associated with high ambient humidity that exist in
Portugal during the normal course of storage. High ambient temperatures also exist during
the storage period and this can create optimal values for insect pest activity. The presence of
fungus-feeding insect species is not only an indicator of fungal production, but it is also an
indication of unsuitable or a non-homogeneous storage conditions. Although, Sitophilus spp

Carvalho M. O, Barbosa A., Magro A., Timlick B., Adler C., Marques, P., Teixeira, A.,
Jesus O., Mexia A (2005). Insects of stored rice in Portugal: fungus-feeders,
commodity-feeders and beneficials. Proceedings of Meeting of Working Group 4,
COST 842, Barcelona, Spain, October 28-29, 2004: 11-15.
2
(S. zeamais and S. oryzae) are the most important rice pests, others such as Oryzaephilus
surinamensis, Tribolium spp and Cryptolestes spp are also very destructive and common in
Portugal. In the event that chemical control is not applied, beneficial insects (predators and
parasitoids) may occur and cause a reduction in the pest population. Due to growing public
concerns about the use of insecticides, biological control using natural enemies may be an
effective alternative to traditional control methods.
It is the intent of this investigation to examine the insects associated with stored paddy and
milled rice in Portugal, their ecosystems and to examine factors that may lead to successful
biological control.
Material and Methods
Collecting sampling data
After harvest, paddy is cleaned and dried to 13-14% moisture. Most paddy is initially stored
on farms and will be periodically delivered to the mills over the course of the storage period
(October to March). At the rice mill, paddy is stored prior to processing. Both farm storage
and storage at the rice millmay be of two types, horizontal warehouses and silos, and have
the equipment for cleaning, weighing, drying and aeration.
Farm storage
Trials were conducted on paddy in farm storage belonging to the rice farmers association of
Sado Valley region, from November 2002 to March 2004. Of the 12 rice farmers belonging
to the association, 7 have their own storage (horizontal warehouses and one silo structure).
The type of storage and the number and type of insect traps used in each location are
presented in Table 1. The traps were observed weekly and insects were counted and
identified.
To determine the environmental conditions of the farm stored paddy, two data loggers were
placed in Store 1 and Store 5 and one thermohygrograph in the silo structure. Three
thermometers inside paddy stored in one silo and one multi-channel data logger with five
temperature sensors inside paddy in Store 5, were placed to determine temperature.
Rice mill
Trials have been conducted, from April 2003 to date, in the rice mill located in Santiago do
Cacém. This facility usually processes the previous paddy from the rice farmers association
of Sado Valley. The location sampled and the number and type of traps used in each place
are presented in Table 2.
The traps were observed biweekly and insects were counted and identified.
For determining environmental conditions at the rice mill a thermohygrograph was placed in
the factory from 15 April to August 2003. One multi-channel data logger with five
temperature sensors was placed in the brown rice from 1 April to 7 July 2004 to determine
grain temperature.
Detecting fungi
The rice samples were surface disinfected with 1% sodium hypochlorite for 2 minutes, as
described by King et al. (1986).

Carvalho M. O, Barbosa A., Magro A., Timlick B., Adler C., Marques, P., Teixeira, A.,
Jesus O., Mexia A (2005). Insects of stored rice in Portugal: fungus-feeders,
commodity-feeders and beneficials. Proceedings of Meeting of Working Group 4,
COST 842, Barcelona, Spain, October 28-29, 2004: 11-15.
3
One gramme of rice was plated in Petri dishes with Potato Dextrose Agar (PDA). For each
sample three replicates were made. The incubation conditions were 28ºC for 8 days.
After incubation, each single kernel was examined under a light stereomicroscope for fungal
growth. Slides of fungal growth were prepared and observed under a compound microscope
for study of the fungal morphology. Identification was carried out using identification keys.
At the same time, isolation of the colonies was made to obtain pure cultures.
Table 1- Farm storage: locations sampled, total of paddy rice stored in each storage
structure, type and number of traps used and trial period.
Local
Paddy rice
(tonnes)
Type of trap
Trial period
Pitfall
Probe
Dome
Store 1 gaxa
510
626
10
6
7 Nov. 02 – 24 Jan. 03
5 Dec. 03 – 27 Jan. 04
Store 2 Marinhais
590
423
10
6
19 Dec. 02 – 9 Jan. 03
27 Jan. – 19 Feb. 04
Store 3 Porto Carro
300
259
10
3
6
7 Nov. 02 – 7 Mar 03
5 Dec. 03 – 02 Mar. 04
Store 4 Laxique
240
262
10
6
7 Nov. 02- 5 Dec. 03
5 Dec. 03 – 30 Mar. 04
Store 5 ValeLobos
317
6
5 Dec. 03 – 23 Mar. 04
Store 6 Oliveira
538
6
5 Dec. 03 - 27 Mar. 04
Store 7 epac
2017
6
21 Jan. 03 – 7 Mar. 03
Silos
structure
Silo
300
9
9
7 Nov. 02 – 28 Mar. 03
Floor
-
-
12
7 Nov. 02 – 11 Apr. 03
Table 2.- Rice mill: locations sampled, total of rice stored in each storage structure, type and
number of traps used and trial period.
Local
Rice
(tonnes)
Type of trap
Trial period
Pitfall
Probe
Dome
Thinline
Store 1
paddy rice
946
500
8
8
5
-
-
15 Apr. – 18 Jul.03
2 Jan. 04 – 18 May 04
brown rice
2000
2000
2000
9
18
7
9
14
-
-
15 Apr. – 18 Jul.03
17 Oct. – 21 Nov. 03
> 17 Oct.04
Factory
-
-
-
15
30
10
24 May – 18 Jul. 03
>18 May 04
Store 2
white rice
257
8
4
-
-
24 May – 6 Jun.03

Carvalho M. O, Barbosa A., Magro A., Timlick B., Adler C., Marques, P., Teixeira, A.,
Jesus O., Mexia A (2005). Insects of stored rice in Portugal: fungus-feeders,
commodity-feeders and beneficials. Proceedings of Meeting of Working Group 4,
COST 842, Barcelona, Spain, October 28-29, 2004: 11-15.
4

Carvalho M. O, Barbosa A., Magro A., Timlick B., Adler C., Marques, P., Teixeira, A.,
Jesus O., Mexia A (2005). Insects of stored rice in Portugal: fungus-feeders,
commodity-feeders and beneficials. Proceedings of Meeting of Working Group 4,
COST 842, Barcelona, Spain, October 28-29, 2004: 11-15.
5
Results
Environmental conditions
Farm storage
The mean temperature of paddy rice in the silo was 21.4  2.0ºC from December 2002 to
April 2003 and in Store 5 it was 13.2ºC  2.7º C from 2 January 2004 to March 2004. The
mean temperature was 14.6  0.4ºC from December 2002 to April 2003 and 10.9º  2.1ºC
from December 2003 to March 2004. The relative humidity was 72.5  1.6% from
December 2002 to April 2003 and 86.9%  4.4% from December 2003 to March 2004..
Rice mill
During summer 2003 the mean temperature in the factory was 25.6  0.4ºC and ranged from
24.5ºC to 26.5ºC. The relative humidity was 60.5  4.1%.
The mean temperature of brown rice was 22.8  1.5ºC during June 2003 and 21.2  3.8ºC
from April to July 2004.
Insect detection
The insect species collected at the farm storage and at the rice mill are presented in Table 3.
32 insect species were identified in paddy rice warehouses and silo structures (farm storage)
while at the rice mill 18 insect species were recorded from the trap catches.
Table 3 -Insect species, mites and Psocoptera caught in the traps placed at the farm storage
and rice mill
Feeding
habits
Species
Farm
storage
Rice mill
Paddy
Paddy
Brown
rice
White
Rice
Factory
Anobiidae
C
Stegobium paniceum (L.)
+
Anthicidae
C
Anthicus floralis (L.)
+
+
C
Anthicus quadriguttatus Rossius
+
+
Bostrichidae
C
Rhyzopertha dominica (F.)
+
Carabidae
P
Harpalus rufipes (Degeer)
+
Cryptophagidae
F
Cryptophagus cellaris (Scopoli)
+
F
Cryptophagus saginatus Sturm
+
F
Cryptophagus perrisi Brisson
+
Cucujidae
C
Cryptolestes turcicus (Grouvelle)
+
C
C. ferrugineus (Stephens)
+
+
+
Curculionidae

Carvalho M. O, Barbosa A., Magro A., Timlick B., Adler C., Marques, P., Teixeira, A.,
Jesus O., Mexia A (2005). Insects of stored rice in Portugal: fungus-feeders,
commodity-feeders and beneficials. Proceedings of Meeting of Working Group 4,
COST 842, Barcelona, Spain, October 28-29, 2004: 11-15.
6
Feeding
habits
Species
Farm
storage
Rice mill
Paddy
Paddy
Brown
rice
White
Rice
Factory
Ck
Sitophilus oryzae (L.)
+
+
+
+
Ck
Sitophilus zeamais Motsch.
+
+
+
+
Lathridiidae
F
Coninomus constrictus (Gyllenhal
+
F
Coninomus nodifer (Westwood)
+
+
F
Coninomus bifasciatus (Reitter)
+
Mycetophagidae
F
Litargus balteatus LeConte
+
F
Typhaea stercorea (L.)
+
+
+
Nitidulidae
C
Carpohilus dimidiatus (F.)
+
Ptinidae
S
Ptinus raptor Sturm
+
Silvanidae
C,F
Ashaverus advena (Waltl)
+
C
Monotoma sp.
+
C
Oryzaephilus surinamensis (L.)
+
+
Staphylinidae
P
Aleochara sparsa
+
P
spp.
+
+
+
Tenebrionidae
C,P
Tribolium castaneum (Herbst)
+
+
+
C,P
T. confusum Duval
+
C,P
Gnathocerus cornutus (F.)
+
F
Alphitobius piceus
+
Pyralidae
C
Plodia interpunctella (Hb.)
+
Gelechiidae
C
Sitotroga cerealella (Olivier)
+
Pteromalidae
Pc
Lariophagus distinguendus (Förster)
+
Pc
Anisopteromalus calandrae (Howitz)
+
Braconidae
Pl
Braconinae sp.
+
+
Bethylidae
Pc
Cephalonomia waterstoni Gahan
+
+
+
Anthocoridae
P
Lyctocoris campestris F.
+
P
Xylocoris flavipes(Reuter)
+
+
Acaridae
C
Glycyphagus domesticus
+
+
P
Cheyletus spp
+
+
+
F
Psocoptera
+
+
+
C=commodity-feeders; Ck=key pest; F=fungus-feeders; P=predators; Pc=Coleoptera parasitoid;
Pl=Lepidoptera parasitoid

Carvalho M. O, Barbosa A., Magro A., Timlick B., Adler C., Marques, P., Teixeira, A.,
Jesus O., Mexia A (2005). Insects of stored rice in Portugal: fungus-feeders,
commodity-feeders and beneficials. Proceedings of Meeting of Working Group 4,
COST 842, Barcelona, Spain, October 28-29, 2004: 11-15.
7
Fungus-feeders
Many species of stored-product Coleoptera are exclusively fungus-feeders (Cryptophagidae,
Lathridiidae and Mycetophagidae Families) and others may supplement their diet by feeding
on mould on the surface of grains in humid conditions (A. advena and A. piceus). When
fungi are present, spores may become attached to the insect body surface and insects are
therefore considered vectors of fungi (Haines, 1991). The presence of large numbers of
fungus-feeders in paddy stores is an indicator of fungal presence and of appropriate
ecological conditions (temperature and moisture) for insect development and reproduction.
This type of information should be utilized to initiate actions such as drying, aeration or
turning of the grain.
Of the fungal feeding insect species discovered, 9 were identified at farm storage and 5 were
identified at the rice mill (Table 3).
Most of the insect species associated with fungi were found in the farm storage and
illustrates some grain management issues (Fig.1). The husk of paddy rice is likely to carry a
great deal of fungal spores, many of which are not killed during drying. The husk is also
porous and easily absorbs moisture which in turn allows for fungal development when
temperatures are appropriate. For example, at farm Store 4, a large number of fungus-
feeders were reported and Aspergillus niger, A. flavus, A. candidus and Penicillium
islandicum were identified from paddy samples taken near the probe traps. The mean
relative humidity ranged from 80.2%, during the first week of March, to 94.1%, during the
second week of December.
Abundant Psocoptera were recorded at brown rice stored at rice mill warehouse.
0
0.2
0.4
0.6
0.8
1
1.2
Farm storage Rice mill
Percentage of total insects caught
Fungus-feeders
Other species
Fig. 1 – Percentage of the total of fungus-feeders insects caught at the farm storage and rice
mill
Commodity-feeders
Rice feeding insect species caught at farm storage and rice mill are presented in Table 3.

Carvalho M. O, Barbosa A., Magro A., Timlick B., Adler C., Marques, P., Teixeira, A.,
Jesus O., Mexia A (2005). Insects of stored rice in Portugal: fungus-feeders,
commodity-feeders and beneficials. Proceedings of Meeting of Working Group 4,
COST 842, Barcelona, Spain, October 28-29, 2004: 11-15.
8
Sixteen commodity-feeding insect species were present at the farm storage but, except in
Store 5, their presence was occasional. At Store 5 abundant populations of Cryptolestes
turcicus , followed by Tribolium castaneum, occurred during January and February 2004
and the rice was fumigated in February 2004.
At the rice mill, more than 90% of the total of insects caught were commodity-feeder
species. The main species were C. ferrugineus followed by the key-pest Sitophilus spp
(mainly S. zeamais). From the total caught, 95%, in 2003 and 65% in 2004?, was C.
ferrugineus. Sitophilus spp. represented 3%, in 2003?4 and 30%, in 2004 from all insects
collected.
Farm storage
0
10
20
30
40
50
60
70
80
90
100
Cryptolestes turcicus Tenebrionidae O. surinamensis Sitophilus spp. Others
Percentage total of insects caught
2002-2003 2003-2004
Fig. 2 - Percentage of the total of commodity-feeders insects caught at the farm storage

Carvalho M. O, Barbosa A., Magro A., Timlick B., Adler C., Marques, P., Teixeira, A.,
Jesus O., Mexia A (2005). Insects of stored rice in Portugal: fungus-feeders,
commodity-feeders and beneficials. Proceedings of Meeting of Working Group 4,
COST 842, Barcelona, Spain, October 28-29, 2004: 11-15.
9
Rice mill
0
10
20
30
40
50
60
70
80
90
100
C. ferrugineus Sitophilus spp O. surinamensis Tenebrionidae Others
Percentage of total insects caught
2003 2004
Fig. 3 - Percentage of the total of commodity-feeders insects caught at the rice mill
Beneficials: predators and parasitoids
At farm storage, three species of predators were identified on paddy stored in warehouses: H
rufipes (1 insect), L. campestris (1 insect), X. flavipes (33 insects) and Staphylinidae spp.
(86 individuals). For the Coleopteran parasitoids, only one wasp of each species, D. basalis
and L. distinguendus, was caught during March 2003 and 14 wasps of A. calandrae during
March 2004 at Store 4.
At the rice mill, only one predator X. flavipes was caught in brown rice. The populations of
the parasitic wasps A. calandrae and C. waterstoni, associated with Sitophilus spp and
Cryptolestes spp. respectively, were monitored from probes, pitfall traps (at the surface and
at 15 cm depth) and brown rice samples, during a six week period, (Figs. 4 and 5).
During this six week period, 2536 adults of Sitophilus spp. and 617 wasps of A. calandrae
were caught. Following the population fluctuation of both species, it can assumed that there
is a density dependent relationship between the host and parasitoid (Fig 4). This is more
evident from pitfall traps records, at 15 cm depth.
In the same period, 90725 adults of C. ferrugineus and 1570 wasps of C. waterstoni, were
caught. The relative density of wasps, compared with the high abundance of C. ferrugineus,
shows a poor efficient relation between host and parasitoid.
Comparing the type of sampling, the probe traps caught more wasps than the pitfall traps.
There were no meaningful differences between probe traps and grain samples for collecting
A. calandrae.

Carvalho M. O, Barbosa A., Magro A., Timlick B., Adler C., Marques, P., Teixeira, A.,
Jesus O., Mexia A (2005). Insects of stored rice in Portugal: fungus-feeders,
commodity-feeders and beneficials. Proceedings of Meeting of Working Group 4,
COST 842, Barcelona, Spain, October 28-29, 2004: 11-15.
10
Probe (mean trap catches)
0
20
40
60
80
100
120
17-10-2003 24-10-2003 31-10-2003 07-11-2003 14-11-2003 21-11-2003
Sitophilus spp
0
1
2
3
4
5
6
7
8
9
Anisopteromalus calandrae
Sitophilus
A. calandrae
Brown rice samples
0
2
4
6
8
10
12
14
16
17-10-2003 24-10-2003 31-10-2003 07-11-2003 14-11-2003 21-11-2003
Mean trap catches
Sitophilus
A. calandrae
Pitfall surface
0
1
2
3
4
5
6
7
8
9
24-10-2003 31-10-2003 07-11-2003 14-11-2003 21-11-2003
Mean trap catches
Sitophilus
A. calandrae
Pitfall under 15 cm
0
1
2
3
4
5
6
7
24-10-2003 31-10-2003 07-11-2003 14-11-2003 21-11-2003
Mean trap catches
Sitophilus
A. calandrae
Fig. 4 – Mean trap catches of Sitophilus spp and Anisopteromalus calandrae using probe,
pitfall (at surface and under 15 cm depths) traps and taking brown rice samples
Probes (Mean trap catches)
0
500
1000
1500
2000
2500
17-10-2003 24-10-2003 31-10-2003 07-11-2003 14-11-2003 21-11-2003
Cryptolestes ferrugineus
0
10
20
30
40
50
60
70
80
Cephalonomia waterstoni
C. ferrugineus
C. waterstoni
Samples (mean trap catches)
0
5
10
15
20
25
30
17-10-2003 24-10-2003 31-10-2003 07-11-2003 14-11-2003 21-11-2003
sample
Cryptolestes ferrugineus
0
0.5
1
1.5
2
2.5
3
3.5
4
Cephalonomia waterstoni
C. ferrugineus
C. waterstoni
Pitfall surface (mean trap catches)
0
200
400
600
800
1000
1200
1400
1600
1800
24-10-2003 31-10-2003 07-11-2003 14-11-2003 21-11-2003
Cryptolestes ferrugineus
0
2
4
6
8
10
12
Cephalonomia waterstoni
C. ferrugineus
C. waterstoni
Pitfall under 15 cm (mean trap catches)
0
100
200
300
400
500
600
700
800
24-10-2003 31-10-2003 07-11-2003 14-11-2003 21-11-2003
Cryptolestes ferrugineus
0
1
2
3
4
5
6
7
8
9
Cephalonomia waterstoni
C. ferrugineus
C. waterstoni

Carvalho M. O, Barbosa A., Magro A., Timlick B., Adler C., Marques, P., Teixeira, A.,
Jesus O., Mexia A (2005). Insects of stored rice in Portugal: fungus-feeders,
commodity-feeders and beneficials. Proceedings of Meeting of Working Group 4,
COST 842, Barcelona, Spain, October 28-29, 2004: 11-15.
11
Fig. 5 – Mean trap catches of Cryptolestes ferrugineus and Cephalonomia waterstoni using
probe, pitfall (at surface and under 15 cm depths) traps and taking brown rice samples
Discussion
We think there needs to be some recommendation on trap placement and monitoring
schedules in order for those managing rice to: 1) determine when aeration may be necessary,
2) determine when fumigation may be necessary (this brings in the economic threshold topic
which was eluded to previously)
More insect species were found in the farm storage than in the rice mill. At farm storage, the
main insects caught were fungus-feeders and mycotoxin producing fungi were also detected.
Given that the relative humidity determined from this study (during paddy storage) ranged
from 75% to 85%, the logistics of implementing aeration schemes may be difficult. Other
non-chemical options may be to initiate drying schedules throughout the storage period or to
consider more sophisticated storage to reduce manpower costs. Data on the time affecting
the moisture gradient between the rice and the ambient conditions were not collected in this
study and may prove useful to assist the development of time based management systems. It
is apparent that the high relative humidity and the resulting moisture content of the stored
rice is a major factor affecting paddy storage, which in turn is a major contributor to
allowing fungal production and insect development.
Insect infestations are likely to occur relatively soon after conditions become appropriate.
The insect pest infestations (especially Sitophilus spp.) create damage and consequently
allow for more fungal production. Those managing rice should consider the damaged grain,
from these two factors, seriously as it results in direct economic loss.
At the rice mill, the main insects caught were commodity feeders , especially Sitophilus spp.
(S. oryzae and mainly S. zeamais). Predators and parasitoids were recorded but most of them
were occasional. During trials, when Sitophilus spp and Cryptolestes ferrugineus
populations were high, their associated parasitoids, Anisopteromalus calandrae and
Cephalonomia waterstoni, were also reported in some abundance. The presence of natural
enemies may encourage studies of using them in a program of biological control.
Acknowledgements
The authors express their gratitude: to APARROZ and the associated paddy rice farmers, for
allowing the trials in their stores and silo structures, especially to the manager and friend
João Reis Mendes; to SEAR, for allowing the trials in the rice mill especially to Dr. Romano
Mancini; to Trécé (Salinas, EUA), especially to Bill Lingren and Selina AA-Stewart for
supplying the Storgard Dome, Probe II and Thinline traps; to Matthias Schöller for
Bethylidae identification; to Jordi Riudavetis for his contribution to this study; and to
Alberto Vargues, from National Agronomic Station, for loan of the multi-channel data
logger.

Carvalho M. O, Barbosa A., Magro A., Timlick B., Adler C., Marques, P., Teixeira, A.,
Jesus O., Mexia A (2005). Insects of stored rice in Portugal: fungus-feeders,
commodity-feeders and beneficials. Proceedings of Meeting of Working Group 4,
COST 842, Barcelona, Spain, October 28-29, 2004: 11-15.
12
References
Haines, C. P. (1991). Insects and arachnids of tropical stored products: their biology and
identification (A training manual). NRI, Chatham, 246p.
King, A. D., Pitt, J. I., Beuchat, L. R., Corry, J. E. L. (eds.) (1986). Methods for mycological
examination of foods. Plnum Press, New York.
Papers related to this work:
M. O. Carvalho, A. F. Barbosa, P. Marques, B. Timlick ; C. Adler and A. Mexia (in press.).
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