2nd European Seminar on the European Learning Network on Functional AgroBiodiversity

1
Example of promising results from functional
agrobiodiversity in Greece
Dionyssios Perdikis
Laboratory of Agricultural Zoology and
Entomology AGRICULTURAL UNIVERSITY OF ATHENS,
HELLAS

• 2nd European Seminar on the European Learning
  Network on Functional AgroBiodiversity
• 24-25 September, 2009, Research Institute of
  Organic Agriculture, Frick, Switzerland

2
Conservation Biological Control
Conservation of natural biological control agents
has recently attracted considerable attention as
important component in the development of
sustainable farming systems
An important element of this conservation is the
non-crop vegetation that may enhance the buildup
of natural enemies and their migration into crops

• 2nd European Seminar on the European Learning
  Network on Functional AgroBiodiversity
• 24-25 September, 2009, Research Institute of
  Organic Agriculture, Frick, Switzerland

3
Parasitoids
4
Predators
5
(No Transcript)
6
Conservation of natural enemies in vegetable
fields in Greece

• Polyphagous predators of the family Miridae are
  important candidates for conservation biological
  control because they are native species, very
  common on vegetable crops and natural
  colonization of vegetable fields has been proved
  to contribute in the biological control of
  vegetable insect pests in Greece and in other
  Mediterranean countries

7
Main insect pests of vegetables
Whiteflies
Thrips
Aphids
8
Polyphagous mirid predators that occur in
vegetable fields
Macrolophus pygmaeus
Macrolophus melanotoma ( M. caliginosus)
9
Biological characteristics

• They feed on several insect pests
  (whiteflies, aphids, mites )

10
Nymphal development of Macrolophus pygmaeus on
different diets at 25oC
11
They feed on the plant sap of several
vegetables they develop and survive relatively
well
12
..but with relatively low reproductive potential
13
They naturally occur in the agroecosystems on
non-cultivated host plants

• Macrolophus melanotoma

• Macrolophus pygmaeus

Solanum nigrum
Dittrichia viscosa
14
They naturally occur in the agroecosystems on
non-cultivated host plants

• Macrolophus spp.

• Cistus cretica

15
Evaluation of the potential of natural host
plants to support natural Macrolophus populations
in the field
16
Number (mean SE) of Macrolophus caliginosus
individuals recorded on Dittrichia viscosa plants
and percentage of plant stems infested with
aphids in the field in 2001 (A) and 2002 (B).
17
They feed on naturally occurring prey on
non-cultivated host plants

• Macrolophus melanotoma
• (M. caliginosus)

• Macrolophus pygmaeus

on Dittrichia viscosa the aphid prey Capitophorus
inulae
on Solanum nigrum the aphid prey Aphis fabae
solanella
18
Biological characteristics (mean SE) of
Macrolophus melanotoma on Dittrichia viscosa
with or without the aphid Capitophorus inulae, at
25C
19
Life table parameters of Macrolophus
caliginosus on Dittrichia viscosa leaves with or
without the aphid Capitophorus inulae, at 25C
Perdikis et al. Acta Oecologica 2007
20
Biological characteristics (mean SE) of
Macrolophus pygmaeus when fed on Solanum nigrum
leaves, with or without the aphid prey Aphis
fabae solanella
21
Life-table parameters of Macrolophus pygmaeus
when fed on Solanum nigrum leaves, with or
without the aphid prey Aphis fabae solanella, at
25C
Lykouressis et al,. Biol. Control (accepted)
22
Biological characteristics (mean SE) of
Macrolophus pygmaeus on Dittrichia viscosa with
or without the aphid Capitophorus inulae, at 25C
23
Life-table parameters of Macrolophus pygmaeus
when fed on Dittrichia viscosa with or without
the aphid Capitophorus inulae
Fig.10. Representative RAPD profile of the 16
accessions analyzed with primers OPA 18 and OPA
20. Letters correspond to accessions
(DDittrichia, T Tomato , S Solanum nigrum ,
X marker samples from lab material. A1, A2
different individuals from the same collection).
24
Conclusions

• The experiments proved that the non-cultivated
  plants Dittrichia viscosa and Solanum nigrum
  support the maintenance of Macrolophus melanotoma
  and Macrolophus pygmaeus populations in the field

• However, Dittrichia viscosa is not a suitable
  plant for the predator Macrolophus pygmaeus

25
Evaluation of the potential of natural
Macrolophus populations to colonize tomato crops
Edge effect on colonization of field crops
Large scale experiments
Introduction of natural host plants in
greenhouse crops
Caged plants
Small scale choice experiments in
Petri dishes
26
Evaluation of the potential of natural
Macrolophus populations to colonize tomato
crops (1)

• Large scale experiments were conducted in tomato
  fields

• Edge effects in field colonization of the
  predators was evaluated by taking samples from
  the tomato plants but also from the surrounding
  natural vegetation (Dittrichia viscosa, Solanum
  nigrum plants) in the growing seasons of 2005 and
  2006.

27
(No Transcript)
28
(No Transcript)
29
Number of aphids and predators recorded on tomato
plants
30
Number of aphids and predators recorded on
Dittrichia viscosa plants
31
Number of aphids recorded on Solanum nigrum
plants
32
Number of predators recorded on Solanum nigrum
plants
33
The numbers of aphids and predators in a row
34
Conclusions

• The naturally occurring plant Dittrichia
  viscosa was the main natural reservoir of the
  predator Macrolophus melanotoma (M. caliginosus)
  in the agroecosystem

• Solanum nigrum is a suitable host plant for
  Macrolophus pygmaeus although it does not host
  high numbers of this predator

• The presence of Dittrichia viscosa or Solanum
  nigrum plants in opposite field edges was not
  proved to contribute to the field colonization
  by Macrolophus predators

35
Evaluation of the potential of natural
Macrolophus populations to colonize tomato
crops (2)

• Large scale experiments were conducted in 4
  tomato greenhouses

• In each greenhouse a treatment plot and a
  control plot were determeined. In each
  experimental plot 9 potted Dittrichia viscosa or
  Solanum nigrum plants were introduced. On each of
  them a high number of Macrolophus individuals was
  released.

• The surrounding tomato plants along with tomato
  plants from a control plot were inspected at
  weekly intervals for the presence of Macrolophus.

36
(No Transcript)
37
(No Transcript)
38
Evaluation of the potential of natural
Macrolophus populations to colonize tomato
crops (3)

• Small scale choice experiments were conducted
  in greenhouse tomato crops

• Two tomato plants with 20-22 leaves were
  enclosed in each cage together with a potted
  Ditrichia viscosa or Solanum nigrum plant bearing
  10-20 Macrolophus adults.

• In the next 3 days the number of predators on
  the muslin, soil surface, non-cultivated plants
  and the tomato plants was recorded in the
  morning and in the evening of each day.

39
(No Transcript)
40
(No Transcript)
41
(No Transcript)
42
(No Transcript)
43
(No Transcript)
44
(No Transcript)
45
Evaluation of the potential of natural
Macrolophus populations to colonize tomato crops
(3)

• Small scale choice experiments were conducted
  in the laboratory

• In Petri dishes one tomato leaf together with
  one Dittrichia viscosa or Solanum nigrum leaf
  were placed. In addition one tomato plant
  together with one Dittrichia viscosa or Solanum
  nigrum plant were placed in appropriate cages. In
  each dish one Macrolophus melanotoma or M.
  pygmaeus adult was introduced. Its movement was
  recorded for 20 minutes and its position 1, 2 and
  24h later.

46
Representative RAPD profile of the 16 accessions
analyzed with primers OPA 18 and OPA 20. (D
Dittrichia viscosa, T Tomato, S Solanum
nigrum , X tomato from lab. A1, A2 different
individuals of the same collection).
Fig.10. Representative RAPD profile of the 16
accessions analyzed with primers OPA 18 and OPA
20. Letters correspond to accessions
(DDittrichia, T Tomato , S Solanum nigrum ,
X marker samples from lab material. A1, A2
different individuals from the same collection).
47
Conclusions

• The results of the large scale and small scale
  choice experiments showed no evidence that the
  Dittrichia viscosa plants can support the
  colonization of tomato by Macrolophus melanotoma

• However, the results of the large scale and
  particularly those of the small scale choice
  experiments provide sufficient evidence that the
  Solanum nigrum plants can substantially support
  the colonization of tomato by Macrolophus pygmaeus

48
General Conclusions

• The results give further evidence that support
  the previous results of crossing experiments and
  molecular analyses (Perdikis et al. 2003
  Martinez-Cascales et al. 2006) that Macrolophus
  on the two host plants belong to different
  species or at least to different biotypes

• Macrolophus pygmaeus is the species that can
  colonize tomato and therefore the use of the name
  Macrolophus caliginosus for the Macrolophus used
  in commercial scale should be replaced by M.
  pygmaeus

49

• Dittrichia viscosa

• It is a very common perennial herb

• Hosts high number of Macrolophus melanotoma
  even during winter

• It is not an invasive weed

• It is not at least a major host of pests

• It can easily develop in pots

But unfortunately it hosts a Macrolophus species
that was not proved able to colonize tomato crops
50
Solanum nigrum

• It is a very common annual plant

• It is the most important host plant of
  Macrolophus pygmaeus although the predator does
  not develop high populations on this plant but
  only at the end of the season

• It is an invasive weed

• It is a host of insect pests and pathogens

• Although it supports the Macrolophus species that
  colonize tomato, the several constraints make its
  use questionable and necessitate further
  experimentation. However, if conserved, the
  farmers can collect predators and release them in
  the greenhouses.

51
Orius spp. (Hemiptera Anthocoridae)
52
(No Transcript)
53
(No Transcript)
54
(No Transcript)
55
Other crops Olives
56
The olive fruit fly Bactrocera oleae
57
Main natural enemy the parasitoid Opius concolor
58
The black scale Saissetia oleae
59
Metaphycus lounsburyi
Metaphycus helvolus
Diversinervus elegans
M. bartletti
Scutellista nigra
60
The fruit moth Prays oleae
61
The fruit moth Prays oleae
62
Neuroptera Chrysopidae
63

• Hemiptera Anthocoridae

64
Chalcidoidea Trichogrammatidae
65
(No Transcript)
66
(No Transcript)
67
(No Transcript)
68
General conclusions

• The small farm size, the high crop
  diversification, the variety of microclimates,
  the rich flora and fauna but also the need for
  the production of higher quality food indicate
  that natural conservation can be significant in
  farmland of Greece

• However, substantial efforts are required in
  order to realize the importance of each element
  of biodiversity in the agro-ecosystem functions
  and to develop further appropriate strategies for
  enhancing functional agro-biodiversity.

69
Thank you very much for your attention!
70
(No Transcript)
71
(No Transcript)
72
(No Transcript)
73
(No Transcript)
74
(No Transcript)
75
(No Transcript)
76
(No Transcript)
77
(No Transcript)
78
(No Transcript)
79
(No Transcript)
80
(No Transcript)
81
(No Transcript)
82
(No Transcript)
83
(No Transcript)