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Effect of root-knot and reniform nematodes on plant growth and bulk-density of plant residues of pigeonpea
Biological Wastes 30 (1989) 245-250
Effect of Root-Knot and Reniform Nematodes on Plant Growth and Bulk-Density of Plant Residues of Pigeonpea Suhail A n v e r & M. M a s h k o o r A l a m * Department of Botany, Aligarh Muslim University, Aligarh-202002, India (Received 9 February 1989; revised version received 16 March 1989; accepted 29 March 1989)
ABSTRACT Different varieties of pigeonpea showed varied reactions to the root-knot nematode Meloidogyne incognita and reniform nematode Rotylenchulus reniformis. Loss in plant weight, number of pods per plant, chlorophyll content of leaves and bulk density of stem parts was directly correlated with the multiplication of the nematodes, the highest being in susceptible varieties with minimal or no change in resistant varieties. Variety ICPL 8562 showed resistance to M. incognita and variety ICPL 87 to R. reniformis.
INTRODUCTION Pigeonpea (Cajanus cajan L.) is an important and widely grown pulse crop in India. Not only is it an important source of vegetable protein, but the woody stem residues have great potential as a substitute to the ever-increasing demand for solid fuel. A survey conducted in the Aligarh district revealed the presence of the root-knot nematode, Meloidogyne incognita (Kofoid & White) Chitwood, and reniform nematode, Rotylenchulus reniformis Linford & Oliveira, on pigeonpea. A number of crop cultivars have been screened for their reaction against M. incognita (Hasan & Khan, 1983; Sasser & Hartman, 1985) and R. reniformis (Patel et al., 1987; Thakar & Yadav, 1987). In all these reports the effect of these nematodes on the growth ofpigeonpea has not been studied. It was therefore considered worthwhile to * To whom correspondenceshould be addressed. 245 Biological Wastes 0269-7483/89/$03.50 © 1989 Elsevier SciencePublishers Ltd, England. Printed in Great Britain
246
Suhail Anver, M. Mashkoor Alam
find out the damaging potential of these nematodes to plant growth and bulk-density of plant residues of pigeonpea.
METHODS Five seeds of different varieties of pigeonpea were sown to 15 cm earthen pots containing steam-sterilized soil (clay, sand and compost mixture in the ratio of 7:2:1), after surface sterilization with 1% mercuric chloride and then thorough washing with sterilized distilled water. After germination, plants were thinned to one per pot. Three-week-old plants were inoculated with 5000 freshly hatched second-stage juveniles of M. incognita or freshly isolated specimens of R. reniformis Separately. One set of each variety remained uninoculated as control. Each treatment, as well as the control, was replicated five times. Plant growth characteristics (fresh weight of shoot and root and number of pods) and eggmasses per plant were noted two months after inoculation. Chlorophyll content of the leaves was estimated by the method of Hiscox and Israelstam (1979). Bulk density of dried stems was calculated by dividing the weight (g) by the instantaneous volume (cm3). In the case ofR. reniformis, the final population in the pot soil was isolated with the help of Cobb's sieving and decanting method along with Baermann's funnel technique (Southey, 1986). Reproduction factor (R) was calculated by dividing the final population (Pf) by the initial population (Pi) as suggested by Oostenbrink (1966).
RESULTS A N D DISCUSSION Interesting results were obtained with respect to the reactions of different varieties ofpigeonpea to the root-knot (M. incognita) as well as the reniform (R. reniformis) nematodes. The degree of nematode infection was evident by eggmass production in the case of the root-knot nematode and 'R' factor in the case of the reniform nematode. There was a positive correlation with the intensity of nematode infection and the reduction in the weight of shoot and root, number of pods per plant and bulk density of the woody stem. Rootknot infection caused greatest reduction in various growth parameters, including bulk density in the variety HY 3C, but almost no change in ICPL 8562 (Table 1). The variety ICPL 131 showed the greatest susceptibility to the reniform nematode by way of maximum reduction in plant growth, while variety ICPL 87 was found almost resistant, as there was no appreciable loss in plant growth characteristics (Table 2).
C I C I C I C I C I C I C I C I C I
Treatment
16"40a 7'30b 17-50a 9.20b 17.50a 13"50b 23"00a 10.30b 16"33a 9"50b 17.00a 8-30b 8.00a 8.00a 14"50a 7"50b 17-82a 10.50b
Weight (g)
41"07
48-27
--
51"17
41.82
55-21
22"85
47.42
55.48
% reduction
Plant growth
9a 5b 1la 6b 10a 7b 12a 6b 8a 6b 10a 6b 5a 5a 8a 5b 10a 7b
No. of pods/ plant
2.20a 1'53b 2'34a 1-74b 2-34a l'81b 2.29a 1'79b 2"19a 1"72b 2-38a 1"63b 1"75a 1"73a 2.26a l'60b 2.40a 1"77b
Chlorophyll (chl. a + chl. b) (mg/g)
Each value is an average of five replicates. In columns, figures for a variety followed by the same letter do not differ significantly at P = 0'05. C, Uninoculated control; I, inoculated.
T 7
ICPL 8562 (ANM 669) ICPL 8863
ICPL 270
ICPL 131 (C 11 line) ICPL 151
ICPL 4 (Prabhat line) ICPL 87
HY 3C
Variety
0-27a 0-20b 0-26a 0.21b 0.28a 0"24b 0-30a 0"23b 0-27a 0-22b 0"29a 0-23b 0"25a 0"24a 0-25a 0"20b 0-28a 0"23b
g/cm 3
17"85
20-00
4.00
20"68
18.51
23-33
14"28
19.23
25-92
% reduction
Bulk density
TABLE 1 Pathogenicity of Root-Knot Nematode Meloidogyne incognita to Pigeonpea Varieties
85
101
105
87
118
75
98
120
No. of eggmasses/ plant
t~
q)
C I C I C I C I C I C I C I C I C I
Treatment
16"40a 7-50b 17-50a 9"75b 17.50a 17.45a 23"00a 7-40b 16"33a 9-83b 17-00a 9"90b 8.00a 6"50b 14-50a 7"75b 17-82a ll.00b
Weight (g)
38"27
46-55
18.75
41-76
39"80
67.82
0"28
44-28
54"26
% reduction
Plant growth
9a 6b 1la 7b 10a 10a 12a 4b 8a 7a 10a 7b 5a 3a 8a 5b 10a 8b
No. of pods/ plant
2.20a 1"58b 2'34a 1"79b 2"34a 2-34a 2,29a 1'62b 2"19a 1.83a 2"38a 1"65b 1.74a 1-57a 2-26a 1"62b 2-40a 1.81b
Chlorophyll (chl. a + chl. b) (mg/g)
0-27a 0.21b 0.26a 0-22b 0.28a 0"27a 0.30a 0-20b 0"27a 0"24b 0"29a 0.25b 0.25a 0"23a 0"25a 0-21b 0-28a 0-25b
g/cm 3
10-71
16.00
8"00
13"79
11-11
33"33
3.57
15'38
22-22
% reduction
Bulk density
Each value is an average of five replicates. In columns, figures for a variety followed by the same letter do not differ significantly at P = 0-05. C, Uninoculated control; I, inoculated. R, Reproduction factor; Pf, final population; Pi, initial population.
T 7
ICPL 8562 (ANM669) ICPL 8863
ICPL 270
ICPL 131 (C l l l i n e ) ICPL 151
ICPL 4 (Prabhat line) ICPL 87
HY 3C
Variety
Pathogenicity of Reniforrn Nematode Rotylenchulus reniformis to Pigeonpea Varieties
TABLE 2
2-86
3"66
18321 14295
2"60
13 067
3-39
3"07
15362 16954
4-39
1.00 5090 21952
3.40
3"89
R = (Pf/Pi)
17021
19435
Final nematode population per pot
:x E"
IxJ .gL O0
Nematode effects on pigeonpea bulk density
249
It is well known that these nematodes cause reduction in root-surface area and mechanical injury to the root tissue, thereby impairing water absorption efficiency of the roots (Alam et al., 1974; Ismail & Alam, 1975). The chlorophyll content of the leaf was also reduced by the test nematodes (Tables 1 and 2) which might have adversely affected the photosynthesis of the plant, as has been indicated earlier (Wallace, 1987). All these factors might have contributed towards the overall loss in different growth characters, including the bulk-density of woody stem. There is no report in the literature where the bulk density has been studied in relation to nematode infection. In India, as elsewhere, there is an acute shortage of fuel. This is more so in the case of solid fuels. With the depletion of forest reserves and coal mines the cost of solid fuel has gone up alarmingly. Crop residues with some combustible value are therefore very popular in the rural areas of developing nations. Pigeonpea, besides giving high-value vegetable protein in the form of pulse, has many other uses. The root-nodules enhance the fertility of the soil, whereas the stalk residues have good combustibility and are a favourite fuel among rural people. The present study has clearly revealed that the root-knot and reniform nematodes are not only capable of reducing the plant growth but they also retard pod formation which ultimately affects the yield. They also effectively retard the bulk density of the stem, or in other words the combustibility of stem residues. The resistant varieties, where nematodes could not sustain, have thus escaped this reduction in the fuel-energy accumulated by the plant. Jain et al. (1986) have applied uniaxial pressure to increase bulk density of crop residues, including pigeonpea. Our study has revealed that the erosion in bulk density of pigeonpea due to nematodes can be restricted by using resistant crop cultivars or, perhaps, by controlling these nematodes by other means. ACKNOWLEDGEMENT The authors are highly thankful to Dr Laxman Singh, Principal Pigeonpea Breeder, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), India, for providing seeds of pigeonpea cultivars used in the present investigations. REFERENCES Alam, M. M., Hasan, N. & Saxena, S. K. (1974). Effect of root-knot nematode, Meloidogyne incognita, on water absorption capability of tomato roots. Indian J. NematoL, 4, 244-6.
250
Suhail Anver, M. Mashkoor Alam
Hasan, A. & Khan, A. M. (1983). Resistance of some pigeonpea cultivars to rootknot nematode. Int. Pigeonpea Newsl., 2, 56. Hiscox, J. D. & Israelstam, G. F. (1979). A method for the extraction of chlorophyU from leaf tissue without maceration. Can. J. Bot., 57, 1332-4. Ismail, W. & Alam, M. M. (1975). Inhibition in the water absorption capability of castor and tomato roots by the infection of the reniform nematode, Rotylenchulus reniformis Linford & Oliveira, 1940. Geobios, 2, 23-4. Jain, A. K., Sharma, V. R. & Pathak, B. S. (1986). A note on the changes in the bulk density of crop residues due to the application of uniaxial pressure. Agric. Wastes, 16, 89-95, Oostenbrink, M. (1966). Major characteristics of the relation between nematodes and plants. Meded Landb.-Hogesch. Wageningen, 66, 3-46. Patel, B. A., Chavda, J. C., Patel, S. T. & Patel, D. J. (1987). Reaction of some pigeonpea lines to reniform nematode (Rotylenchulus reniformis). Int. Pigeonpea Newsl., 6, 57-9. Sasser, J. N. & Hartman, K. M. (1985). Evaluation of some pigeonpea lines for resistance to root-knot nematodes, Meloidogyne spp. Int. Pigeonpea Newsl., 4, 44--5. Southey, J. F. (1986). Laboratory Methods for Work with Plant and Soil Nematodes. Min. Agr. Fish. Food, HMSO, London. Thakar, N. A. & Yadav, B. S. (1987). Evaluation of pigeonpea varieties/lines for resistance against the reniform nematode. Indian J. Nematol., 17, 132-3. Wallace, H. R. (1987). Effects of nematode parasites on photosynthesis. In Vistas on Nematology, ed. J. A. Veech & D. W. Dickson. Soc. Nematol., Inc., Hyattsville, MD, pp. 253-9.
Effect of Root-Knot and Reniform Nematodes on Plant Growth and Bulk-Density of Plant Residues of Pigeonpea Suhail A n v e r & M. M a s h k o o r A l a m * Department of Botany, Aligarh Muslim University, Aligarh-202002, India (Received 9 February 1989; revised version received 16 March 1989; accepted 29 March 1989)
ABSTRACT Different varieties of pigeonpea showed varied reactions to the root-knot nematode Meloidogyne incognita and reniform nematode Rotylenchulus reniformis. Loss in plant weight, number of pods per plant, chlorophyll content of leaves and bulk density of stem parts was directly correlated with the multiplication of the nematodes, the highest being in susceptible varieties with minimal or no change in resistant varieties. Variety ICPL 8562 showed resistance to M. incognita and variety ICPL 87 to R. reniformis.
INTRODUCTION Pigeonpea (Cajanus cajan L.) is an important and widely grown pulse crop in India. Not only is it an important source of vegetable protein, but the woody stem residues have great potential as a substitute to the ever-increasing demand for solid fuel. A survey conducted in the Aligarh district revealed the presence of the root-knot nematode, Meloidogyne incognita (Kofoid & White) Chitwood, and reniform nematode, Rotylenchulus reniformis Linford & Oliveira, on pigeonpea. A number of crop cultivars have been screened for their reaction against M. incognita (Hasan & Khan, 1983; Sasser & Hartman, 1985) and R. reniformis (Patel et al., 1987; Thakar & Yadav, 1987). In all these reports the effect of these nematodes on the growth ofpigeonpea has not been studied. It was therefore considered worthwhile to * To whom correspondenceshould be addressed. 245 Biological Wastes 0269-7483/89/$03.50 © 1989 Elsevier SciencePublishers Ltd, England. Printed in Great Britain
246
Suhail Anver, M. Mashkoor Alam
find out the damaging potential of these nematodes to plant growth and bulk-density of plant residues of pigeonpea.
METHODS Five seeds of different varieties of pigeonpea were sown to 15 cm earthen pots containing steam-sterilized soil (clay, sand and compost mixture in the ratio of 7:2:1), after surface sterilization with 1% mercuric chloride and then thorough washing with sterilized distilled water. After germination, plants were thinned to one per pot. Three-week-old plants were inoculated with 5000 freshly hatched second-stage juveniles of M. incognita or freshly isolated specimens of R. reniformis Separately. One set of each variety remained uninoculated as control. Each treatment, as well as the control, was replicated five times. Plant growth characteristics (fresh weight of shoot and root and number of pods) and eggmasses per plant were noted two months after inoculation. Chlorophyll content of the leaves was estimated by the method of Hiscox and Israelstam (1979). Bulk density of dried stems was calculated by dividing the weight (g) by the instantaneous volume (cm3). In the case ofR. reniformis, the final population in the pot soil was isolated with the help of Cobb's sieving and decanting method along with Baermann's funnel technique (Southey, 1986). Reproduction factor (R) was calculated by dividing the final population (Pf) by the initial population (Pi) as suggested by Oostenbrink (1966).
RESULTS A N D DISCUSSION Interesting results were obtained with respect to the reactions of different varieties ofpigeonpea to the root-knot (M. incognita) as well as the reniform (R. reniformis) nematodes. The degree of nematode infection was evident by eggmass production in the case of the root-knot nematode and 'R' factor in the case of the reniform nematode. There was a positive correlation with the intensity of nematode infection and the reduction in the weight of shoot and root, number of pods per plant and bulk density of the woody stem. Rootknot infection caused greatest reduction in various growth parameters, including bulk density in the variety HY 3C, but almost no change in ICPL 8562 (Table 1). The variety ICPL 131 showed the greatest susceptibility to the reniform nematode by way of maximum reduction in plant growth, while variety ICPL 87 was found almost resistant, as there was no appreciable loss in plant growth characteristics (Table 2).
C I C I C I C I C I C I C I C I C I
Treatment
16"40a 7'30b 17-50a 9.20b 17.50a 13"50b 23"00a 10.30b 16"33a 9"50b 17.00a 8-30b 8.00a 8.00a 14"50a 7"50b 17-82a 10.50b
Weight (g)
41"07
48-27
--
51"17
41.82
55-21
22"85
47.42
55.48
% reduction
Plant growth
9a 5b 1la 6b 10a 7b 12a 6b 8a 6b 10a 6b 5a 5a 8a 5b 10a 7b
No. of pods/ plant
2.20a 1'53b 2'34a 1-74b 2-34a l'81b 2.29a 1'79b 2"19a 1"72b 2-38a 1"63b 1"75a 1"73a 2.26a l'60b 2.40a 1"77b
Chlorophyll (chl. a + chl. b) (mg/g)
Each value is an average of five replicates. In columns, figures for a variety followed by the same letter do not differ significantly at P = 0'05. C, Uninoculated control; I, inoculated.
T 7
ICPL 8562 (ANM 669) ICPL 8863
ICPL 270
ICPL 131 (C 11 line) ICPL 151
ICPL 4 (Prabhat line) ICPL 87
HY 3C
Variety
0-27a 0-20b 0-26a 0.21b 0.28a 0"24b 0-30a 0"23b 0-27a 0-22b 0"29a 0-23b 0"25a 0"24a 0-25a 0"20b 0-28a 0"23b
g/cm 3
17"85
20-00
4.00
20"68
18.51
23-33
14"28
19.23
25-92
% reduction
Bulk density
TABLE 1 Pathogenicity of Root-Knot Nematode Meloidogyne incognita to Pigeonpea Varieties
85
101
105
87
118
75
98
120
No. of eggmasses/ plant
t~
q)
C I C I C I C I C I C I C I C I C I
Treatment
16"40a 7-50b 17-50a 9"75b 17.50a 17.45a 23"00a 7-40b 16"33a 9-83b 17-00a 9"90b 8.00a 6"50b 14-50a 7"75b 17-82a ll.00b
Weight (g)
38"27
46-55
18.75
41-76
39"80
67.82
0"28
44-28
54"26
% reduction
Plant growth
9a 6b 1la 7b 10a 10a 12a 4b 8a 7a 10a 7b 5a 3a 8a 5b 10a 8b
No. of pods/ plant
2.20a 1"58b 2'34a 1"79b 2"34a 2-34a 2,29a 1'62b 2"19a 1.83a 2"38a 1"65b 1.74a 1-57a 2-26a 1"62b 2-40a 1.81b
Chlorophyll (chl. a + chl. b) (mg/g)
0-27a 0.21b 0.26a 0-22b 0.28a 0"27a 0.30a 0-20b 0"27a 0"24b 0"29a 0.25b 0.25a 0"23a 0"25a 0-21b 0-28a 0-25b
g/cm 3
10-71
16.00
8"00
13"79
11-11
33"33
3.57
15'38
22-22
% reduction
Bulk density
Each value is an average of five replicates. In columns, figures for a variety followed by the same letter do not differ significantly at P = 0-05. C, Uninoculated control; I, inoculated. R, Reproduction factor; Pf, final population; Pi, initial population.
T 7
ICPL 8562 (ANM669) ICPL 8863
ICPL 270
ICPL 131 (C l l l i n e ) ICPL 151
ICPL 4 (Prabhat line) ICPL 87
HY 3C
Variety
Pathogenicity of Reniforrn Nematode Rotylenchulus reniformis to Pigeonpea Varieties
TABLE 2
2-86
3"66
18321 14295
2"60
13 067
3-39
3"07
15362 16954
4-39
1.00 5090 21952
3.40
3"89
R = (Pf/Pi)
17021
19435
Final nematode population per pot
:x E"
IxJ .gL O0
Nematode effects on pigeonpea bulk density
249
It is well known that these nematodes cause reduction in root-surface area and mechanical injury to the root tissue, thereby impairing water absorption efficiency of the roots (Alam et al., 1974; Ismail & Alam, 1975). The chlorophyll content of the leaf was also reduced by the test nematodes (Tables 1 and 2) which might have adversely affected the photosynthesis of the plant, as has been indicated earlier (Wallace, 1987). All these factors might have contributed towards the overall loss in different growth characters, including the bulk-density of woody stem. There is no report in the literature where the bulk density has been studied in relation to nematode infection. In India, as elsewhere, there is an acute shortage of fuel. This is more so in the case of solid fuels. With the depletion of forest reserves and coal mines the cost of solid fuel has gone up alarmingly. Crop residues with some combustible value are therefore very popular in the rural areas of developing nations. Pigeonpea, besides giving high-value vegetable protein in the form of pulse, has many other uses. The root-nodules enhance the fertility of the soil, whereas the stalk residues have good combustibility and are a favourite fuel among rural people. The present study has clearly revealed that the root-knot and reniform nematodes are not only capable of reducing the plant growth but they also retard pod formation which ultimately affects the yield. They also effectively retard the bulk density of the stem, or in other words the combustibility of stem residues. The resistant varieties, where nematodes could not sustain, have thus escaped this reduction in the fuel-energy accumulated by the plant. Jain et al. (1986) have applied uniaxial pressure to increase bulk density of crop residues, including pigeonpea. Our study has revealed that the erosion in bulk density of pigeonpea due to nematodes can be restricted by using resistant crop cultivars or, perhaps, by controlling these nematodes by other means. ACKNOWLEDGEMENT The authors are highly thankful to Dr Laxman Singh, Principal Pigeonpea Breeder, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), India, for providing seeds of pigeonpea cultivars used in the present investigations. REFERENCES Alam, M. M., Hasan, N. & Saxena, S. K. (1974). Effect of root-knot nematode, Meloidogyne incognita, on water absorption capability of tomato roots. Indian J. NematoL, 4, 244-6.
250
Suhail Anver, M. Mashkoor Alam
Hasan, A. & Khan, A. M. (1983). Resistance of some pigeonpea cultivars to rootknot nematode. Int. Pigeonpea Newsl., 2, 56. Hiscox, J. D. & Israelstam, G. F. (1979). A method for the extraction of chlorophyU from leaf tissue without maceration. Can. J. Bot., 57, 1332-4. Ismail, W. & Alam, M. M. (1975). Inhibition in the water absorption capability of castor and tomato roots by the infection of the reniform nematode, Rotylenchulus reniformis Linford & Oliveira, 1940. Geobios, 2, 23-4. Jain, A. K., Sharma, V. R. & Pathak, B. S. (1986). A note on the changes in the bulk density of crop residues due to the application of uniaxial pressure. Agric. Wastes, 16, 89-95, Oostenbrink, M. (1966). Major characteristics of the relation between nematodes and plants. Meded Landb.-Hogesch. Wageningen, 66, 3-46. Patel, B. A., Chavda, J. C., Patel, S. T. & Patel, D. J. (1987). Reaction of some pigeonpea lines to reniform nematode (Rotylenchulus reniformis). Int. Pigeonpea Newsl., 6, 57-9. Sasser, J. N. & Hartman, K. M. (1985). Evaluation of some pigeonpea lines for resistance to root-knot nematodes, Meloidogyne spp. Int. Pigeonpea Newsl., 4, 44--5. Southey, J. F. (1986). Laboratory Methods for Work with Plant and Soil Nematodes. Min. Agr. Fish. Food, HMSO, London. Thakar, N. A. & Yadav, B. S. (1987). Evaluation of pigeonpea varieties/lines for resistance against the reniform nematode. Indian J. Nematol., 17, 132-3. Wallace, H. R. (1987). Effects of nematode parasites on photosynthesis. In Vistas on Nematology, ed. J. A. Veech & D. W. Dickson. Soc. Nematol., Inc., Hyattsville, MD, pp. 253-9.