1. F. Franco-Navarro* and D. Godinez-Vidal. *Phytopathology Program-Colegio de Postgraduados-Campus Montecillo, Montecillo 56230, Mexico
F. Franco-
Franco-Navarro* and D. Godinez-
Godinez-Vidal. **Phytopathology Program-
Phytopathology Program-Colegio de Postgraduados-
Postgraduados-Campus Montecillo, Montecillo 56230, Mexico
State, Mexico. *E-mail: ffranco@colpos.mx.
State, Mexico. *E-
State, Mexico. *E-mail: ffranco@colpos.mx.
ffranco@colpos.mx.
Project: Conservation and Sustainable Management of Below-Ground Biodiversity [PROJECT FUNDED BY GEF]
Below-
Soil disturbance indices based on soil nematodes fauna from sites with four land use intensities in
sites
In the context ff the Multinational Project ““Conservation and Sustainable Management of the Below-Ground
In the context the Multinational Project Conservation and Sustainable Management of the Below- Below-Ground the Biosphere Reserve “Los Tuxtlas”, Veracruz, Mexico.
Tuxtlas” Veracruz,
Biodiversity” (CSM/BGBD), a study at the Biosphere Reserve "Los Tuxtlas", Mexico, to determinate the effect of
Biodiversity” (CSM/BGBD), a study at the Biosphere Reserve "Los Tuxtlas", Mexico, to determinate the effect of
Biodiversity” Tuxtlas", Index Natural forest Secondary forest Pasture fields Maize fields
different land use intensities on the soil nematodes was conducted. Three localities into the Reserve were chosen
different land use intensities on the soil nematodes was conducted. Three localities into the Reserve were chosen
conducted.
T 2.57 ns 2.31 ns 2.11 ns 2.36 ns
as replications and from each of them, different fields belonging to four land use intensities (Natural forest,
as replications and from each of them, different fields belonging to four land use intensities (Natural forest,
belonging
Secondary forest, Pasture fields and Maize fields) were selected. Ecological measures of the structure of soil Ff/Bf 0.16 b 0.18 b 0.11 b 0.45 a
Secondary forest, Pasture fields and Maize fields) were selected. Ecological measures of the structure of soil
selected.
nematodes fauna, diversity, and maturity indices were assessed and compared among land uses. Fifty three families WI 0.97 b 0.95 b 1.80 a 3.49 a
nematodes fauna, diversity, and maturity indices were assessed and compared among land uses. Fifty three families
and
and one hundred twenty four genera were identified. The highest nematode abundance, richness of genera and
and one hundred twenty four genera were identified. The highest nematode abundance, richness of genera and MI 2.63 a 2.60 a 2.47 ab 2.37 b
diversity corresponded to Natural forest, closely followed by Secondary forest. Intensive agricultural systems like
Secondary forest. Intensive agricultural systems like
diversity corresponded to Natural forest, closely followed by Secondary PPI 2.91 a 2.85 a 2.68 b 2.68 b
Maize fields and Pasture fields presented low richness of genera and significant lower diversity than non-disturbed
Maize fields and Pasture fields presented low richness of genera and significant lower diversity than non-
non-disturbed mMI 3.21 a 3.15 a 2.93 a 2.87 b
systems. In general, plant-parasitic nematodes and bacterial feeders were the most dominant and abundant in the
systems. In general, plant-
plant-parasitic nematodes and bacterial feeders were the most dominant and abundant in the PPI/MI
PPI/MI 1.15 ns 1.13 ns 1.18 ns 1.18 ns
study area, followed by fungal feeders, omnivores and finally predators. The higher number of bacterial feeders
predators. The higher number of bacterial feeders
study area, followed by fungal feeders, omnivores and finally predators. Means followed by different letters are significantly BF FF OM PR PP
different. ns= not significant.
was collected in Pasture fields and Maize fields; fungal feeders were more abundant in Maize fields, omnivores and
was collected in Pasture fields and Maize fields; fungal feeders were more abundant in Maize fields, omnivores and T= Trophic diversity index 100%
predators in Natural forest and Secondary forest, and plant-parasitic in Secondary forest. Some disturbance indices
predators in Natural forest and Secondary forest, and plant-
plant-parasitic in Secondary forest. Some disturbance indices 90%
Ff/Bf= fungal feeders/bacterial feeders ratio
(Maturity index, Plant parasite index, modified Maturity index, and plant parasite index/maturity index ratio)
(Maturity index, Plant parasite index, modified Maturity index, and plant parasite index/maturity index ratio) WI= ratio of microbial feeder nematodes
80%
70%
showed differences among land uses, corresponding most of the highest values to non-disturbed systems
showed differences among land uses, corresponding most of the highest values to non-
highest non-disturbed systems MI= maturity index 60%
(Natural and Secondary forest). In general, the conditions of the food chain in the study area correspond to a low
(Natural and Secondary forest). In general, the conditions of the food chain in the study area correspond to a low
the PPI= plant parasite index 50%
40%
to moderate disturbance, non-enriched, with canal of decomposition balanced by fungi and bacteria, low C/N
to moderate disturbance, non-
non-enriched, with canal of decomposition balanced by fungi and bacteria, low C/N
bacteria, mMI= modified maturity index
mMI=
30%
ratio and food chain in maturation. Most of the ecological indices were useful to establish significant effects of
ratio and food chain in maturation. Most of the ecological indices were useful to establish significant effects of
indices PPI/MI= plant parasite index/maturity index ratio. 20%
10%
different land uses on soil nematodes fauna in the study area.
different land uses on soil nematodes fauna in the study area. 0%
Natural forest Secondary Pasture fields Maize fields
forest
SAMPLING
SAMPLING In each land use
BIOSPHERE RESERVE 24 sampling points
FOUR LAND USES BACTERIAL FEEDERS
“LOS TUXTLAS”, VERACRUZ, MEXICO
TUXTLAS” (distance: 200 m)
distance:
Maize fields Acrobeles
Aphanolaimus
Pasture fields PREDATORS Plectus
Desmocolex
Secondary forest Mononchus Prismatolaimus
Natural forest Miconchus Rhabditis
Prionchulus Diploscapter
Mylonchulus
SUBSAMPLING POINT
Trypila
SAMPLING POINT IN THE GRID
Iotonchus
EXTRACTION, COUNTING, PROCESSING & MOUNTING
EXTRACTION, COUNTING, PROCESSING & MOUNTING
EXTRACTION: Sieving–Sugar flotation method (300 g per sample)
Sieving– sample)
COUNTING:
Three countings (1 ml)
TOTAL: Average of 3 countings X 10.
PERMANENT MOUNTINGS
Nematodes killed by heat at 60°C for 1
60°
min, and then fixed with cold formalin
4%
MASS DEHYDRATION
OMNIVORES
53 Families & 124 Genera Mesodorylaimus
Oriverutus
Belondira
SIMPSON’S DIVERSITY INDEX
SIMPSON’ SHANNON’S DIVERSITY INDEX
SHANNON’ Labronema
12
a 3
a PLANT-
PLANT-
ab ab Aporcelaimium
10
ab ab
2.5 b PARASITES
8 b 2 FUNGAL FEEDERS
6 Helicotylenchus Aphelenchus
1.5
Criconema
Ogma
4 1
2 0.5 Discocriconemella
0
Trophorus
Hemicycliophora
0
NATURAL SECONDARY PASTURE MAIZE NATURAL SECONDARY PASTURE MAIZE
FOREST FOREST FIELDS FIELDS FOREST FOREST FIELDS FIELDS Xiphinema
Pratylenchus
30 a GENERA RICHNESS Meloidogyne
Trichodorus
25 b b
b
20
15
10
1. ESQUIVEL, A. 2003. Nematode fauna of Costa Rican Protected areas. Nematropica 33(2): 131-145. 2. NEHER, D. A. 2001. Role of
1. ESQUIVEL, A. 2003. Nematode fauna of Costa Rican Protected areas. Nematropica 33(2): 131-
areas. 131-145. 2. NEHER, D. A. 2001. Role of
nematodes in soil health and their use as indicators. Journal of Nematology 33(4): 161-168. 3. POWERS, T. O., NEHER, D. A., MULLIN, P.,
nematodes in soil health and their use as indicators. Journal of Nematology 33(4): 161-
indicators. 161-168. 3. POWERS, T. O., NEHER, D. A., MULLIN, P.,
5 ESQUIVEL, A., GIBLIN-DAVIS, R. M., KANSAKI, N., STOCK, S. P., MORA, M. M. & URIBE-LORIO, L.. 2009. Tropical nematode diversity:
ESQUIVEL, A., GIBLIN-
GIBLIN-DAVIS, R. M., KANSAKI, N., STOCK, S. P., MORA, M. M. & URIBE-URIBE-LORIO, L.. 2009. Tropical nematode diversity:
diversity:
vertical stratification of nematode communities in aa Costa Rican humid lowland rainforest. Molecular Ecology. pp. 1-12. 4. YEATES, G. W.,
vertical stratification of nematode communities in Costa Rican humid lowland rainforest. Molecular Ecology. pp. 11-12. 4. YEATES, G. W.,
rainforest. Ecology. -
0 BONGERS, T., DE GOEDE, R. G. M., FRECKMAN, D. W. & GEORGIEVA, S. S. 1993. Feeding habits in soil nematode families and genera-an
BONGERS, T., DE GOEDE, R. G. M., FRECKMAN, D. W. & GEORGIEVA, S. S. 1993. Feeding habits in soil nematode families and genera-
Feeding genera-an
NATURAL SECONDARY PASTURE MAIZE outline for soil ecologists. Journal of Nematology 25(3): 315-331.
outline for soil ecologists. Journal of Nematology 25(3): 315-
315-331.
FOREST FOREST FIELDS FIELDS
1