Journal of Global Resources
Volume 4
ISSN: 2395-3160 (Print), 2455-2445 (Online)

January 2017

Page 108-112

14VERTICAL DISTRIBUTION AND DIVERSITY OF PREDATORY SOIL NEMATODES IN
AGRICULTURAL CROPS
Mamta Gehlot
Department of Zoology, Jai Narain Vyas University, Jodhpur, India
E-mail: mamtagehlot99@gmail.com
Pankaj Nama
Department of Zoology, Jai Narain Vyas University, Jodhpur, India
Abstract: The present work is taken out to study the vertical distribution and diversity ofpredatory nematodes from agricultural crops in and around Jodhpur, Rajasthan during theyear Nov 2009 to Oct 2011. The vertical distribution of soil nematodes is closely related tothe distribution of plant root, new emerged roots, moist soil, crops, soil type, pH, temperatureand other environmental factors. Total nematode population from 0-5 cm of soil depth was
found to be significantly increased, than at 20-25 cm depth of soil, the numbers ofnematodes were slightly decreases.
Key words: Vertical Distribution, Agricultural Crops, Temperature, pH.
Introduction
Nematodes are extremely widespread and to be found in most unexpected places, they arealso inconceivably abundant according to Cobb (1914). Generally, nematodes arecylindrical, unsegmented, bilaterally symmetrical pseudocoelmates (Reven et al., 1986).
They are also known as 'eelworms' and 'roundworms'. Nematodes are found n a wide
variety of habitats, from the Antarctic to the hot springs in New Zealand. In soil they areimportant components of nutrient turn over. Most nematodes live in the interstitial spaces
between soil particles, or other substratum. Nematodes associated with seasonal functionaland vertical distribution of plant-feeding nematodes in grasslands by Verschoor et al.,(2000). Vertical distribution in Bacteriovorous nematodes under different land uses wasstudied by Liang et al. (2005). Qualitative and quantitative study on plant and soil nematodes
associated with crops of economic importance in Rajasthan has been done by Bohra (2008).
The movement of nematodes in the soil by their own activities is limited at most to a 5cm to25cm depending upon the plant root and moisture. It is obvious that the number ofnematodes is greater in soil containing plant roots than in soil without plant roots.
Material and Methods
To study the vertical distribution of soil nematodes in the agriculture field samples werecollected from different depth (0.5, 5-10, 10-15, 15-20, or 20-25cm) from single selected
fields cultivated with wheat, bajra, onion and cauliflower (table 1). Nematodes were extracted
from composite soil samples in the laboratory by COBB (1918) modified Sieving anddecantation techniques. The nematodes were fixed in hot 4 percent form a line and storedfor analysis. The species and genera of nematodes were identified using standard text
(NORTON, D.C., 1978). The population of nematodes in each sample was counted using
stereoscopic zoom microscope and the statistical analysis of the vertical distribution wasdone by analysis of variance (ANOVA) and chi square test as shown in the table 2, 3 and 4.

108

Table 1: Vertical Distribution of Soil Nematodes (100g soil)
Nematodes

0-5 cm(soil depth)

5-10 cm(soil depth)

10-15 cm
(soil depth)

15-20 cm
(soil depth)

20-25 cm
(soil depth)

Bathyodontus

56921

10Mononchulus

791228

15Oionchus

235117Iotonchus

3571911Mylonchulus

67924

14Mononchus

481026

13

RESULTS
Total Nematode Population
From table 1 the vertical distribution of soil nematodes population from 0-5 cm to 15-20 cm
was found to be significantly increase, than at 20-25cm depth, the number of nematodes
was slightly decrease. More than 90 percent of soil nematodes were present in 0-20 cm soil
depth.
At the Depth of 0-5 cm Soil
Fewer than 5 cm soil total 27 nematodes were found from the host plant of wheat, bajra,
onion and cauliflower. The maximum number of nematodes was found in Mononchulus i.e.,
7 and minimum number of nematodes were found in Oionchus and 5, 3, 6 and 4 number ofnematodes were found from the Bathyodontus, Iotonchus, Mylonchulus and Mononchus
respectively. The highest percentage of nematodes Population were found in Mononchulus
with 23 percent and minimum percentage of nematodes were found in Oionchus with 8percent.
At The Depth of 5-10 cm Soil
Under 0-10 cm soil total 52 nematodes population were found from the four soil samples ofhost plant. The highest percentage of nematodes Mononchulus was 23 percent andminimum percentage of nematodes Oionchus was 9 percent. Bathyodontus, Iotonchus,Mylonchulus and Mononchus were 17 percent, 13 percent, 17 percent and 19 percent
respectively.
At the Depth of 10-15 cm SoilLess than 15cm soil the population of nematodes was 52 from 4 soil samples. The maximum
number of nematodes was found in Mononchulus i.e.12 and minimum number of nematodes
was found in Oionchus. Out of 52 number of nematodes 9 were present in Bathyodontus
with 17 percent, out of 52, 7 number of nematodes with 13 percent were present inIotonchus, out of 52, 9 nematodes with 17 percent were present in Mylonchulus and out of52, 10 nematodes with 19 percent were present in Mononchus.
At the Depth of 15-20 cm Soil
Under the depth of 20cm of soil the total number of nematodes population was 129. Out of
which 21 were present in Bathyondontus with 16 percent, out of 129, 28 with 21 percent ofnematodes were present in Mononchulus, out of 129, 11 with 8 percent of nematodes werepresent in Oionchus, out of 129, 19 with 14 percent nematodes were present in Iotonchus
out of 129, 24 with 18 percent of nematodes and 26 with 20 percent of nematodes werepresent in Mylonchus and Mononchus respectively.
At the Depth of 20-25 cm Soil
Under the depth of 0-25cm of soil the number of nematodes population was decreases ascompare to 0-20cm of soil depth. The total number of nematode population i.e. 70 waspresent at the depth of 0-25cm of soil. The maximum number of nematodes was present in109

Mononchulus i.e. 15 with 21 percent of nematodes and minimum number of nematodes waspresent in Oionchus i.e. 7 with 10 percent nematodes. 10 with 14 percent, 11 with 15percent, 14 with 20 percent, and 13 with 18 percent of nematodes were present inBathyondontus, Iotonhcus, Mylonchus and Mononchus respectively.
Percentage of Soil Nematodes from the Depth of 0-5 to 20-25 cm of Soil
From the table 4, under the depth of 5-25cm of soil nematodes population was occupied by
the member of genera Bathyodontus was 51 percent, Mononchulus was 71 percent,Oionchus was 28 percent, Iotonchus was 45 percent, Mylonchulus was 60 percent andMononchus was 61 percent. The maximum percentage of nematodes was found to be inMononchulus genera (71 percent) and the minimum percentage of nematodes was found tobe in Oionchus (28 percent) (Graph 1)
Graph 1: Percentage of Soil Nematodes in Vertical Distribution of Different Soil Depth,During November 2009 to 2011.
4540
35300-5 cm

255-10 cm

2010-15 cm

1515-20 cm

1020-25 cm

50Bathyotontus Mononchulus Oionchus

Iotonchus

Mylonchulus Mononchus

The Average Values of Nematodes from 0-5 to 0-25 cm Depth of Soil
The maximum average mean values were found under the depth of 0-20 cm of depth soil i.e.
21.5 percent and the minimum average mean values were found under the depth of 0-5 cmof depth soil i.e. 4.5 percent. At the depth of 10cm soil 6.3 percent, at the depth of 15cm ofsoil 8.6 percent and at the depth of 25cm of soil 11.6 percent average mean values wereobtained. According to the table 2, 3 and 4, vertical distribution of soil nematodes underdifferent depth of soils, two-way analysis of variance and chi-square test was applied asa tool for the statistical verification. It reveals significant results and the value of chi-square
test was 1.85 obtained.
Table 2: Analysis of Variance of Vertical Distribution of Soil Nematodes in Different
Depth of Soil During Year November 2009 to October 2011
SSdf
MSF
Source of variation
Between Nematodes

225.8667

545.17333

12.35369

Between vertical depth

1074.467

4268.6167

73.45943

Error

73.13333

203.656667

Total1373.467

29110

Table 3: Analysis of Variance of Vertical Distribution of Soil Nematodes in Different
Depth of Soil during Year November 2009 to Oct 2011.
SSDfMSF
Source of variation
Between Group1074.464268.622992511.96

1373.46

29

Within group
Total

22.45

Table 4: The Chi-Square Test in Vertical Distribution of Soil Nematodes in Different
Depth of Soil during the Year 2009-2011. (Cm. & percent)
0-5%

5-10

Bathyodontus

59.80

6

Percent
Mononchulus

18.52
79.86

Percent
Oionchus

25.93
2Percent
Iotonchus

10-15%

15-20%

20-25%

Total

11.76

97.6
52141.
181019.61

51

15.79
9

12.68

17.31
12

14.29
15

21.13

71

7.14

23.68
3

10.71

23.08
5

21.43
7

25.0

28

7.41
3

6.67

7.89
5

11.11

9.62
7

10.0
11

24.44

45

Percent
Mylonchulus

11.11
6

10.0

13.16
7

11.67

13.46
9

15.71
14

23.33

60

PerentMononchus

22.22
4

6.56

8.42
8

13.11

17.31
10

20.0
13

21.31

61

Percent
Total

14.81
27

21.05
38

%

19.23
52

16.
90
17.
86
15.
56
15.
00
16.
39

16.28
28
21.71
11
8.53
19
14.73
24
18.60
26
20.16
129

39.
4
39.
29
42.
22
40.
00
42.
62

18.5770Chi.- Square 1.85
Discussion
The differences detected in vertical distribution above could be related to factors of soil type
(Yeates, 1980), root wag pattern (Penmouratove et al., 2004), anthropogenic distribution(Yeates and King, 1997). Sampling seasons (Liang et al., 1999) and so on. Differences in
distribution of nematodes under soil in different strata may be due to the difference in food(Sohlenius and Sandor, 1987). Total carbon and nitrogen in soil also affect the availability
and distribution of soil nematodes (Yeates, 1980). Vertical distribution is also related with thepH of the soil as hydrogen ion concentration is a limiting factor for the survival, of thedominant genera. Similar studies have been done for Bactereovores nematodes by Liang(2005). Wei Ou et al. (2004) analyzed the vertical distribution of soil nematodes under
different land use types in an aquic brown soil and all the data were subjected to statisticalanalysis of variance (ANOVA) in the SPSS statistical package. It revealed significant results.
Meng Fan-Ziang et al. (2006) evaluate vertical distribution and seasonal fluctuation ofnematode tropic groups as affected by land use, all data were also subjected to statisticalanalysis of variance (ANOVA). Differences with p < 0.05 were considered significant. HouXuekun et al. (2010) studied vertical distribution of soil nematode communities and used
two-way ANOVA for all tests, statistically significant result were found (p < 0.05). All
statistical analysis was performed by SPSS software package. This work will be helpful infield of parasitology as ecology of soil nematodes.

111References
1. Bohra, P., (2008) Quantitative and qualitative studies on plant and soil Nematodes
associated with crops of economic importance in Rajasthan. Zool. Survey of India.
Occasional paper no. 278.
2. Cobb, N.A. (1918) Estimating the nema population of the soil. U.S. Department ofAgriculture. Agricultural Technical Circular of US Department of Agriculture 1 : 48p
3. HOU Xuekun, HU Ning, ZHANG Xiaoke, LIANG Lei, ZHAI Ruichang, (2010) Vertical
Distribution of Soil Nematode Communities under Different Tillage Systems in Lower
Reaches of Liaohe River.
4. Liang, W. J., Zhang, X. K., Li, Q., Jiang, Y., Ou, W. and Neher, D. A. (2005) Vertical
distribution of bacterivorous nematodes under different land uses. J. Nematol. 37: 254258.
5. Liang, W.J., Lavian, I., Steinberger, Y., (1999) Dynamics of nematode community
composition in a potato field. Pedobiologia 43, 459–469.
6. MENG Fan-Xiang, OU Wei1, LI Qi1T JIANG Yong1i, and WEN Da-Zhong’, (2006)
Vertical Distribution and Seasonal Fluctuation of Nematode Trophic Groups as Affectedby Land Use , ‘Key Laboratory of Terrestrial Ecological Process, Institute of Applied
Ecology, Chinese Academy of Sciences, Shenyang.
7. Norton, D.C., (1978) Ecology of plant parasitic nematodes. A Wiley Interscience
Publication. John Wiley and Sons. New York. 68.
8. Raven, Peter H and George B. Johnson, (1986) Biology. Times Mirror: St. Louis.
9. Pen-Mouratov, S., Rakhimbaev, M., Barness, G., Steinberger, Y., (2004) Spatial andtemporal dynamics of Vertical distribution of soil nematodes nematode populations
under Zygophyllum dumosum in arid environments. Eur. J. Soil Biol. 40, 31–46.
10. Sohlenius, B., and A. Sandor, (1987) Vertical distribution of nematodes in arable soil
under grass (festuca pratensis) and barley (Hordeum distichum). Biology and Fertility ofsoils, 3: 19-25.
11. Wei Oua,b, Wenju Lianga, Yong Jianga, Qi Lia,b, Dazhong Wena, (2004) Vertical
distribution of soil nematodes under different land use types in an aquic brown soil .
Institute of Applied Ecology, Chinese Academy of Sciences.
12. Yeates, G.W., (1980) Populations of nematode genera in soils udner pasture. III Vertical
distribution at eleven sites. New Zealand Journal of Agriculture Research 23: 117-128.
13. Yeates, G.W., (1980) Populations of nematode genera in soils under pasture: III. Vertical
distribution at eleven sites. N. Zeal. J. Agric. Res 23, 117–128.
14. Yeates, G.W., King, K.L., (1997) Soil nematodes as indicators of the effect ofmanagement on grasslands in the New England Tablelands (NSW): comparison ofnative and improved grasslands. Pedobiologia 41, 526–536.

112