NEMATODE COMMUNITIES AS BIOINDICATORS OF ANTROPOGENIC INFLUENCE IN AGROECOSYSTEMS

1
NEMATODE COMMUNITIES AS BIOINDICATORS OF
ANTROPOGENIC INFLUENCE IN AGROECOSYSTEMS

• Mirjana BRMEZ, Marija IVEZIC, Emilija RASPUDIC,
  Vesna TRIPAR, Renata BALICEVIC
• University of J.J. Strossmayer in Osijek, Faculty
  of Agriculture in Osijek, Croatia

2
Nematodes as bioindicators

• they occur in almost every habitat (terrestrial,
  aquatic and marine),
• they occure with many species per sample or
  habitat,
• they respond quickly to environmental changes,
• they show specific respond to various types of
  pollution or disturbances,
• they are in close contact with dissolved
  compounds in free soil water,

3
Nematodes as bioindicators

• they are easily sampled and extacted from the
  soil,
• the sampling can be done in any time of the year,
• storage of the samples requires little space
• Analyses of nematode community structure can be
  related to feeding types (trophic group), c-p
  groups from 1-5, absolute abundances, number of
  genera, Maturity index, Plant parasitic index
  etc.

4
C-p groups (1-5)

• Colonizers
• short life cycle
• tolerance to disturbances
• high reproductive rate
• high colonization ability
• have voluminous gonads,
• release large numbers of small eggs, and are
  often viviparous

• Persisters
• long life-cycle
• sensitive to disturbances
• low reproduction rate
• they hardly fluctuate in number over the year
• never belong to dominant species in the sample
• have few small gonads, and produced large eggs

5
(No Transcript)
6
(No Transcript)
7
(No Transcript)
8
Maturity index (Bongers, 1990)

• v(i) (c-p) value assigned to family (i)
• f(i) - the frequency of family (i) in a sample
• Lower index reflect disturbance

9
Aim

• The objective of this investigation was to
  determine if the nematode communities in the soil
  could serve as bioindicators of anthropogenic
  activities in agroecosystems.

10
MATERIAL AND METHODS

• TREATMENTS
• Poplar forest,
• Arable land with standard tillage regimes
  wheat,
• Arable land with standard tillage regimes corn.
• Sampling in spring period 2001, in the 4
  replicates, using sonda Ø 2 cm, on the depth of
  20 cm

11
MATERIAL AND METHODS

• Extaction of nematodes 100 g of soil -
  Seinhorst method (1956)
• Identification genus level

12
RESULTS
13
RESULTS
14
RESULTS
Tretments Average MI Average PPI Average PPI/MI Average Total no. nematodes Average no. genera
poplar 1,95 2,40 1,27 1386 20,25
wheat 1,72 2,58 1,50 1922 17,25
corn 1,57 2,83 1,83 2456 14,50
Lsd 0,05 n.s. n.s. 0,3751 n.s. 3,4758
Lsd 0,01 n.s. n.s. n.s. n.s. n.s.
15
CONCLUSION
On the base of this investigations we can
conclude that nematode communities could serve as
a very bood bioindicator of antropogenic
influence in agroecosystem.
16
Acknowledgement

• The investigations are suported by the
  Ministry of Science and Technology in Croatia
  (Project- 079024).