THE ROLL OF BIOLOGICAL AGENTS IN REGULATING PLANT PARASITIC NEMATODES INFECTING TOMATO PLANTS.

Transcription

1 THE ROLL OF BIOLOGICAL AGENTS IN REGULATING PLANT PARASITIC NEMATODES INFECTING TOMATO PLANTS. BY H. H. HENDY** ;H. I. EL-NAGAR* A. A. OSMAN* AND A. A. FARAHAT* Dept., Zool.& Nematol., Fac. of Agric., Cairo Univ. **Nematol. Unit., Plant Protec. Dep., Desert Res. Centre. EGYPTIAN JOURNAL OF APPLIED SCIENCE Vol. ( 9 ), No. (5), May, 1994 ABSTRACT The effect of certain organic manures (powderet, pigeon manure, poultry manure), sewage water, the biocide (Sincocin) and the systemic nematicide Temik 15% on tomato infected with Meloidogyne spp. and Helicotylenchus spp. was studied. Results of single application indicated that, Sincocin 10% and 15% gave the highest reduction of Meloidogyne larvae and egg masses respectively, while all supplements and sewage water adversely increased larvae. Sewage water decreased egg masses number by 50%. Combination effect of Sincocin 5% + sewage water, and Sincocin 5% + pigeon manure gave the best reduction of Meloidogyne reproduction. Sincocin 1% resulting the highest rate of reduction on Helicotylenchus population by 61%. Aldicarb significantly decreased the Meloidogyne and Helicotylenchus population. Results of double application indicated that Sincocin 1% reduced Meloidlgyne Larvae and egg masses by 73.8 % and 53.7% respectively, while pigeon manure was the only amendment reduced Meloidogyne larvae (47.9%). Pigeon manure, Sincocin 10%, powderet and sewage water gave the highest percent of reduction of Helicotylenchus population (57.6%, 47.1%, 42.3 and 37.6%). Aldicarb (Temik 15%) achieve the best results controlling nematode. INTRODUCTION Very few reports have been recorded concerning the effect of the new biocide Sincocin on plant parasitic nematodes. Mohamed (1989) reported that the treatment of Sincocin on clover and corn plants infected with Meloidgyne incognita gave high reduction of root galling and egg mass formation. Organic soil amendments were reported to possess nematicidal properties in vitro and in vivo (Singh & Sitarmaiah, 1978). The developmental stages of Rotlylenchulus reniformis, Tylenchulus semipenetrans, Meloidogyne incognita, M. javanica and Pratylenchus scrbneri were affected by several organic and inorganic nitrogenous amendments in vitro (Mankau & Mankau, 1975 and Abdel-Rahman et al, 1979). At a low initial nematode densities, the application of organic material may be sufficient to keep some nematode populations below the economic threshold level (Errico and Maio 1980). Hatchability in Meloidgyne javanica was reduced and infectivity and development of the juveniles were considerably retarded by several organic and inorganic amendments (Yousif and Badra 1981). Coosemans (1982) studied the influence of organic materials on the population dynamics of M. halpa. He stated that the addition of 10% compost resulted in a minimum number of root-knot nematode. Maareg (1984) concluded that cattle manure, root wastes and pigeon dung reduced the numbers of M. javanica and increased plant growth. Amin (1985) proved that seven organic manures significantly reduced the numbers of females and egg-masses of B.reniformis on the roots of cowpea. He also added that poultry dropping, pigeon dropping and rabbit dung are the most organic manures that reduced nematode numbers. R /18/96

2 Severity of nematode disease were also limited by the addition of sewage sludge to the soil (Habicht, 1975 and Hunt et al, 1973). Sewage water contains, by composition, many organic and mineral nutrient elements. When nematode-infected plants are irrigated with sewage water, plant damage may be compensated. In vitro, sewage water as such or boiled suppressed the egg hatching of Meloidgyne incognita and Rotylenchulus reniformis (Lal and Yadav,1976). Dry sewage sludge has been reported to increase growth of eggplants infected with the reniform nematode, R. reniformis and also decreased number of females on root, (Lal et al,1977). In contrary, Al-Yahya 1986, found that juveniles, eggs and all stages of Tylenchulus semipenetrans were higher in sewage water treatments than in tap water. MATERIALS AND METHODS Two green house pot experiments were under taken to study the effect of some soil organic manures, a new biocide (Sincocin) and sewage water on plant parasitic nematodes infecting tomato plants under green-house condition. Sincocin solution was studied at different concentrations and in a single and combined treatments with the other soil amendments and sewage water. Pigeon dung, poultry dung, powderete and sewage water were used in this study singly or in combination with Sincocin 5%. The organic amendments were used in a single or double doses (2.5 gm/pot). The nematicide Temik 0.2 gm/pot was used to compare the efficacy of the tested materials. Sewage water was used instead of the ordinary irrigation water in some treatments. The farm yard manure and powderete were applied in these trials as dried material (naturally dried). Tomato, Lycopersicon esculentum var. strain B was used in these trials as indicator plant. The root-knot nematodes, Meloidgyne spp. were used in these trials with Helicotylenchus spp as inocula with levels 1,850 2nd stage larvae of the first nematode and 4,000 for the second through using a naturally infested soil from El-Gabal Al-ASfar (sandy soil). The utilized materials were applied 7 days after tomato transplantation which incorporated with the top soil surface and watered immediately. Treatments were replicated six times and pots were arranged in greenhouse in complete randomized block design. Ten cm plastic pots were used as containers in these trials. Three months after transplantion data on nematode population and plant growth were recorded. RESULTS Data on the effect of certain organic amendments, sewage water, Sincocin and the systemic nematicide Temik on tomato plants infected with Meloidgyne spp. and Helicotylenchus are presented in tables (1-4). rates. The applied materials obviously affected nematode development and enhanced plant growth with different From table (1) Sincocin suppressed the total number of Meloidogyne juveniles in soil by different rates except for Sincocin 20% which increased the population by 200%. The highest rate of nematode reduction was associated with Sincocin 10% followed by Sincocin 1%. The application of organic amendments and sewage water adversely increased the nematode population in soil with varying rates. The maximum rate of nematode increase was observed with sewage water followed by powderet pigeon and poultry manures. Regarding the effect of the combined treatments, Sincocin 5%, + sewage water sustained the highest rate of nematode reduction followed by Sincocin 5% + powderete, however and poultry supplements achieved the highest rate of nematode increase as compared with the check treatment. Aldicarb decreased the nematode population in soil much greater than any other treatment. 2

3 The different applied concentration of Sincocin decreased the number of galls. The highest rate of gall reduction was noticed with Sincocin 15% followed by 1%, 10%, 20% and finally with 5%. Poultry manure treatment followed by sewage water treatment decreased the number of galls as compared to the other tested manures. The combined treatments of Sincocin 5% with each of pigeon, sewage water, and poultry manures achieved the highest rates of gall reduction while Sincocin and Aldicarb sustained the outermost reduction in gall formation compared to the other treatments. Sewage water combined with Sincocin increased the rate of gall reduction than the single treatment of sewage water. The same trend was noticed with powderete and pigeon supplements in the combined and single treatments. Sincocin 15% followed by Sincocin 1% and 10% recorded the lowest rates of egg-mass numbers. Sewage water decreased the number of egg-masses by 50% while other tested manures increased the eggmass number by different rates. The addition of Sincocin to the applied organic manures led to an increase in the egg-mass reduction potentiality of these supplements. Sincocin + pigeon manure followed by Sincocin + sewage water clearly reduced the number of egg-masses more than the other tested materials. The highest rate of egg-mass reduction was noticed with Aldicarb. It was worthy to notice that Sincocin 1% followed by Sincocin 10% recorded the highest rates of Helicotylenchus reduction in soil while Sincocin 20% increased the soil population by 31%. The same trend was noticed by sewage water, powderete and poultry which increased the soil population by 123, 32 and 22% respectively. Furthermore, Sincocin 5% + poultry as combined treatment decreased the soil population by 61% Aldicarb manifested the climax of nematode reduction compared to check and the other tested materials. Data in table (2) indicated that all tested concentrations increased the total plant weight except for Sincocin 15% and 20%. The highest rate of plant weight increase was noticed with Sincocin 1% followed by 10% and 5% respectively. Sewage water treatment extremely increased total plant weight by 82% Pigeon manure treatment was the only supplement increasing plant weight by 18.6% while poultry was 5.5%. Aldicarb increased total plant weight by almost 20% compared to check treatment. The combined treatment of Sincocin 5% + sewage water increased plant weight by 70% while single treatment of sewage water was much higher (81.6%). The addition of Sincocin 5% to powderete clearly increased the influence of powderete from 1% to 21%. The same trend was noticed with pigeon manure and poultry. On the other hand, the addition of Sincocin 5% to Aldicarb increased the plant weight from 20% to 49%. The highest plant length increase was displayed by Sincocin 5% + poultry (37%), Sincocin 20% followed by Sincocin 15% were the best treatments among Sincocin concentrations enhanced plant length. The application of different organic manures had resulted in a different rates of plant length increase compared to check. Shoot length of the treated plants were much higher than control plants. The maximum shoot length was associated with pigeon manure treatment followed by Sincocin 5% + sewage water. Sincocin 1% gave the best treatment among Sincocin concentrations which increased shoot fresh weight (21.6%). The combined treatment of Sincocin 5% + pigeon manure gave an outstanding increase of shoot fresh weight by 159%, while sewage water increased shoot fresh weight by 78.8%. 3

4 The most remarkable increase in shoot dry weight was obtained by sewage water combined with Sincocin. It was worthy to notice that, the addition of Sincocin to sewage water decreased to some extent the shoot dry weight of the treated plants from 103 to 90%. Data indicated that different applied substances increased root length by different rates except for certain materials. The highest root lengths were obtained with poultry manure followed by pigeon manure with Sincocin. The application of sewage water affected root weight positively and increased weight by 84.7%. Pigeon manure followed by poultry manure increased root weight by 38.4% and 24% respectively. Sincocin 20% increased root weight by 28%. Results of the effect of organic manures, Sincocin sewage water and nematicides as a double application treatments on tomato plant infected with Meloidgyne and Helicotylenchus are presented in table (3, 4). The only treatment which recorded 73.3% nematode reduction was Sincocin 1%. 0ther tested Sincocin concentrations unfortunately increased soil nematode population to high levels (132.2% for Sincocin 20%) compared to control treatment. Pigeon manure was the only amendment caused nematode reduction by 47.9%. The joint treatment of Sincocin 5% and organic manure increased soil nematode population to higher levels (Sincocin 5% + powderete achieved 416.9% nematode increase). All applied amendments, biocidal solution and sewage water remarkably reduced numbers of galls. The best results of Sincocin concentrations was obtained with 10% followed by 1%, 15%, 20% and 5%,respectively. Powderete application reduced number of galls by 58.5% which surpassed the other organic manures compared to check. Addition of Sincocin to the organic amendments decreased its efficiency in some cases compared to the single treatments of organic amendments. Concerning the effect of these materials on egg-mass formation, except for the joint treatment of Sincocin + powderete, all the tested materials reduced the rate of egg-mass formation compared to check. Among Sincocin concentrations, Sincocin 1% reduced egg-mass formation by the highest rate 53.7%. The addition of Sincocin to soil amendments reduced the efficiency of soil organic manures without any exception. The utilization of the applied materials to some extent reduced the soil population of Helicotylenchus with some exceptions (Sincocin 5%, Sincocin + sewage water, Sincocin + powderete and Sincocin + poultry manure) which increased nematode population more than the check with different rates. Results of the effect of soil amendments, Sincocin nematicides and sewage water as double treatments, on plant growth of tomato are summarized in table (4). Total plant fresh weight was increased by the different treatments except for Sincocin 10, 15 and 20% powderete, and the joint treatment of Sincocin 5% + poultry manure. The addition of sewage water alone or in combination with Sincocin 5% had resulted in an outstanding increase (79.2 and 86.7%) respectively. All the applied materials enhanced total plant length more than the check plants with varied rates. Sewage water and Sincocin 5% recorded the highest plant length increase. Plant shoot was obviously affected by the application in different ways. It was worthy to notice, that the application of sewage water and sewage water joint treatment with Sincocin had resulted in an outstanding effect on shoot length and weight compared to check treatment. 4

5 Applying soil supplements and biocidal solution to manage nematode population in soil indicate that nematode population could be managed by these materials with different degrees. Some of the applied organic manures increased nematode population while the others decreased nematode counts to some extent. The different nematode parameters were affected by the different rates of the used materials. In some cases, the application of Sincocin increased the effect of organic manures in controlling nematodes however contrary results were obtained with other treatments. Generally, some organic manures reduced numbers of nematode in soil, number of root galls, others reduced only nematode in soil or galls on roots. Cultivated soil normally harbors a mixed population of plant parasitic nematodes. The occurrence of 4-6 genera of plant parasitic nematodes and also the occurrence of mixtures of two or more species of a genus at the same place, appeared to be common. There are several observations that manuring relatively suppresses the rate of infestation and reproduction of Heterodera (Duddington 1956, Loan 1956, Oostenbrink 1950, 1952, Reinmuth 1955, Meloidogyne (Johnson 1959, Linford et al 1938, Oostenbrink 1954), Pratylenchus (Oostenbrink 1954) and probably other phytophagous species. Two plausible explanation are the introduction and/or stimulation of nematode-trapping fungi or other predators (Duddington 1956, and Linford et al 1938) and a change in the plant, resulting in a slight resistance (Lasn 1956). Our results indicate that the application of organic manures remarkably reduced nematode population in soil and egg masses on roots. Application of organic matter to the soil usually stimulates microbial action and creates conditions favorable for growth and reproduction of natural enemies of nematodes already present in the soil (Oteifa et al 1964). It has been known for several years that organic manuring influences the development of many nematodes. The application of organic manures increases the tolerance of the plants against diseases. Generally, plots having received farm yard manure had less nematodes and higher yields than those plots treated with artificial fertilizers. At a low initial nematode densities, the application of organic material may be sufficient to keep some nematode populations below the economic threshold (Errico and Maio 1980). Hatchability in Meloidogyne javanica was reduced and infectivity and development of the juveniles was considerably retarded by several organic and inorganic amendments (Yousif and Dadra 1981). Amin (1985) proved that seven organic manures significantly reduced the numbers of females and egg masses of B. reniformis on the roots of cowpea. He also added that poultry dropping, pigeon dropping and rabbit dung are the most organic manures that reduced nematode numbers. The application of organic soil amendments increases the population densities of Enchytraeids, mites, collembolans and insect larvae (Errico and Maio 1980). Organic and inorganic amendments of soil possess nematicidal properties in vitro and in vivo (Sitaramaiah, and Singh 1978). Developmental stages of R. reniformis, Tylenchulus semipenetrans Meloidogyne incognita, M. javanica and PratyIenchus scribneri were affected by several organic and inorganic nitrogenous amendments in vitro (Abd El-Rahman et al, 1979 and Mankau & Mankau 1975). The application of sewage as irrigation water to control certain plant parasitic nematodes in our studies generally indicate, their possibility to be used to nematode control and improving plant growth.sewage water perform two different effects on some fade population. In some cases, the nematode population was clearly increased and in other cases was remarkably decreased and highly reduced. In vitro, sewage water as such or boiled suppressed the egg hatching of Meloidogyne incognita and Rotylenchulus reniformis (Lal and Yadav, 1976). Yeates 1978, reported that population of some nematode genera were higher in pasture site irrigated with dairy shed effluent than in dry land site. This study suggests that sewage water may contains chemical and biological inductive factors that stimulate the nematode reproduction. Sewage water contains, by composition, many organic and mineral nutrient elements when nematode-infected plants are irrigated with sewage water, plant damage may be compensated. 5

6 In our studies powderete (dry sewage sludge) exhibited certain suppressive effect on nematode reproduction and egg mass formation. It has been reported coincided with our results that severity of nematode diseases were limited by the addition of dry sewage sludge (Habicht, 1975). It was worthy to notice that raw sewage sludge was more effective in decreasing root-knot galls than composted sewage sludge. Raw sludge has more available nitrogen than composted sludge. The reduction of galling seems to be related to chemicals, such as ammonia, salt, or organic acids, released during incubation rather to action of antagonistic organisms. Philippe and Kermarrec (1991) found that fewer juveniles of Meloidogyne incognita penetrated roots in pots with raw sludge added to the soil than in unamended control pots, moreover, egg production in treated soil was less than in control pots, also they reported that the Reproductive Factor, RF values (final egg number/inoculation egg number) of the treated pots were strongly reduced. One of the most interesting investigation, which had been done that of Al-Yahya (19B6), who found that juveniles, eggs and all stages of Tylenchulus semipenetrans were higher in sewage water treatments than in tap water. Water extracts from saturated composted municipal refuse induced immobility and death of the sting nematode, Belonolaimus longicaudatus (Hunt et al, 1973 b) With regard to the new biocide Sincocin, our results indicated that this compound reacts differently according to many factors including concentrations, host, nematodes and other ecological factors. Mohamed (1989) found that treatment clover infected with M incognita race I treated with Sincocin 2% and 4% resulted in an % reduction of root galling while induced 16.7% reduction of egg masses by concentration 2% and no effect on egg-mass production with 4%. He also added that this behavior differed when he used corn and wheat plants and achieved an acceptable rates of nematode reduction. Table (1): Effect of soil amendments Sincocin Temik and sewage water as single treatments on tomato plants infected with Meloidgyne and Helicotylenchus under greed house conditions. Meloidogyne Helicotylenchus SOIL RED. GALLS RED EGG RED SOIL RED Treatment % % MASSES % % Sincocin 1% 16,200 d de abc 22 2,400 de 57.6 Sincocin 5% 20,000 d 2.3 1,880 ab ,314 a +31 2,400 bcd 18.8 Sincocin 10% 13,867 d de abc ,333 cde 41.2 Sincocin I5% 19,267 d de bcd ,200 bcd 25.9 Sincocin 20%/ 63,733 a ,128 cde ,067 ab ,467 b Sewage water 55,000 b ,257 bcd bcd ,667 a Powderete 2.5gm 48,467 b ,839 abc ,052 ab ,467 b Pigeon 2.5 gm 33,800 c ,776 abc ,406 a ,267 bcd 7.0 Poultry 2.5gm 31,000 c ,126 cde ,171 ab ,933 bc Temik 15% 0.2 gm 533 e f d e 98.8 Sin. 5% + sewage water 14,133 d def bcd ,600 bcd 1.2 Sin. 5% + powd. 2.5g 39,200 c ,264 bcd abc ,267 a Sin. 5% + pigeon 2.5 g 17,267 d ef cd ,000 bcd 11.7 Sin. 5% + poultry 2.5 g 39,400 c ,158 bcd abc 18 2,200 de 61.2 Sin. 5% + Temik 0.2 gm 800 e f d e Check 20,467 d 2,197 a 1,003 abc 5,667 bcd In each column values followed by the same letter do not differ significantly (p<0.05). 6

7 Table (2) The effect of soil amendments Sincocin, Temik and sewage water as a single treatments on plant growth of tomato infected with Meloidogyne spp. and Helicotylenchus under green house conditions. total plant growth Shoot Root Weight % Length % Length % Fresh % Dry weight % Length % Weight % Treatments gm increase cm increase cm increase weight, gm increase gm increase cm increase gm increase Sincocin 1% 49.2 bc ef def cde efg cd abc 35 5 Sincocin 5% 46.0 bc def cdef cde defg cd bc 20.3 Sincocin 10% 47.8 bc ef ef cde cdefg cd bc l7.5 Sincocin 15% 39.6 c cdef def cde fg abc c 0 6 Sincocin 20% bcde bcde e g bcd bc 28.2 Sewage water 72.3 a abcde ab a a cd a 84.7 Powderete 2.5 gm 40.3 c def def de g cd bc 23.2 Pigeon 2.5 gm 47.2 bc abcde a cde bcdef do abc 38.4 Poultry 2.5 gm 42.0 c abc bcde cde defg ab bc 24.3 Temik 15% 0.2 gm 47.7 bc a abcd bc cdefg a Sin. 5% - sewage water 87.8 a abcd ab a a 90.0 l6.1 cd ab 59.9 Sin. 5% + powd. 2.5 gm 48.3 bd abcd def bc bcd ab bc 7.3 Sin. 5% + pigeon 2.5 gm 51.2 bc ab abcd cd bc ab abc 33.3 Sin 5% + poultry 2.5 gm 50.2 bc ab abc cd bcde ab bc 30.5 Sin 5% + Temik 0.2 gm 59.3 ab a abc ab b ab bc 25.4 Check 39.8 c 43.5 f 27.6 f 22.2 cde 3.0 efg 15.9 cd 17.7 c In each column values followed by the same letter do not differ significantly (P<0.05). 7

8 Table (3) The effect of soil amendments, Sincocin Temik and sewage water as a double treatments on tomato infected with Meloidogyne spp. and Helicotylenchus under green house condition. Meloidogyne spp. Helicotylenchus Treatments In soil % reduction Galls % reduction. Egg masses % reduction. Helioco. % reduction Sincocin 1% 5,467 i b bc ,600 abcd 18.8 Sincocin 5% 21,000 fgh ,407 b b ,133 abc Sincocin 10% 31,833 def b ,000 bcd 47.1 Sincocin 15% 29,777 efg ,014 b bc ,617 bcd 36.2 Sincocin 20% 47,733 c ,248 b ab 3.9 4,400 abcd 22.3 Sewage water 37,000 cde ,246 b ab ,533 bcd 37.6 Rowderete 2.5 gm 42,333 cd b ab ,267 bcd 42.3 Pigeon 2.5 gm 10,667 h ,160 b b ,400 cd 57.6 Poultry manure 2.5 gm 42,200 cd ,298 b b ,483 abc 3.1 Temik 15% 02 gm 467 i c c e 0.0 Sin. 5% - sewage water 60,400 b ,435 b ab 7.8 6,333 abc Sin. 5% + Powd. 2.5 gm 105,800 a ,193 b ,183 a ,267 a Sin. 5% Pigeon 2.5 gm 2,406 fg , b ,067 bd 45.8 Sin. 5% + Poultry 2.5 gm 40,333 cde ,152 b ab ,933 ab Sin. 5% + Temik 0.2 gm 200 i c c e 98.8 Check 20,467 gh 2,197 a 1,003 ab 5,667 abc In each column values followed by the same letter do not differ significantly (p<0.05). 8

9 Table (4) The effect of soil amendments, Sincocin, Temik and sewage water as double treatments on plant growth d tomato infected with Meloidlgyne spp. and Helicotylenchus under green house conditions. Total plant growth Shoot Root Weight % Length % Length % Fresh % Dry weight % Length % Weight % Treatments gm Increase cm increase cm increase weight gm increase cm increase cm increase gm increase Sincocin 1% Sincocin 5% Sincocin 10% Sincocin 15% Sincocin 20% Sewage water Powderete 2.5 gm Pigeon 2.5 gm Poultry 2.5 gm Temik 15% 0. 2 gm Sin. 5% - sewage water Sin. 5% + powd Sin. 5% pigeon 2.5 gm Sin 5% + Poultry 2.5 gm Sin 5% + Temik 0.2gm Check

10 LITERATURE CITED Abd El-Rahman, T., Saleh, M.A & Otiefa, B.A. (1979). Nematicidal activity and composition of some organic fertilizers and amendments. Revue Nematol.,2: Al-Yahyia, Fahad Abdullah,(1986). Effect of irrigation with sewage water on citrus nematode,tylenchulus semipenetrans. M. Se college of Agriculture,King Saud univ.riyadh, Saudia Arabia.79 pp. Amin,W.A.(1985). Factors affecting nematicides efficiency on controlling nematodes.m.sc.thesis fee. of Agric., Cairo univ. pp. 87. Castagnone-Senero, P. and A, Kermarrec(1991). Invasion of tomato roots and reproduction of Meloidogyne incognita as affected by raw sewage sludge. Supplement of Journal of Nematology 23 (4S): Coosemans, J(1982). Influence of organic material on the population dynamics of Meloidgyne halpa Chitwood. Agrieultural wasts,4(3): Duddington, C.L.(1956) The friendly fungi: A new approach to the eelworm problem. London. Faber and Faber, 188 pp. Errieo, F.P.D and F. Di Maio (1980). Effect of some organic materials on root knot nematodes on tomatoes in field preliminary experiments. Nematol. Medit.8: Habicht, W.A. Jr. (1975). The nematicidal effects and varied rates of raw and composted sewage sludge as soil organic amendments on root-knot nematode. Plant Disease Reporter 59: 631 Hunt, P.G.,G. C. Smart, and C.F. Eno. (1973). Sting nematode, Belonolaimus lonqicaudatus, immobility induced by extracts of a composted municipal refuse. J. Nematol. 5: Lal, A., and B.S. Yadav. (1976). Inhibitory effect of sewage on hatching of eggs of root-knot and reniform nematode. Indian J. of Mycology and Plant Pathology 5 (1): Lal, A., B.S. Yadav, and R.P. Nandwana (1977). Effect of chopped leaves of various plants sewage on the plant growth and reniform nematode, Rotylenchulus reniformis. Indian J. of Mycology and Plant Pathology. 7(1): Linford, M. B., Yap, F. and Oliveira, J.M. (1938). Reduction of soil populations of the rootknot nematode during decomposition of organic matter. Soil Sci. 45: Maareg, M.F.M. (1984). The role of organic amendments on controlling nematode. Ph.D. Thesis, Fac. Agric., Menoufia Univ. 188 pp. Mankau, R. and Mankau, S.K. (1975). The effect of NH4 concentrations on selected nematodes in vitro. Nematropical, 5: 25. Mohamed, A.S. (1989). Interaction of plant-parasitic nematodes on certain host plants. Ph.D. Fac. Agric Alexandria,Univ.pp Oostenbrink, M. (1950). Het aardappelaaltje (H. rostochiensis Wollen Weber), Een gevaarlijke parasite voor de eenzijdige aardappelcultuur. Versl. Piziekt.Dienst Wageningen 115: 230 PP. Oostenbrink, M. (1954). Heterodera rostochiensis, Crop rotation in relation to biology. Proc. Int. Nematol. Symp. Harpenden,

11 Oteifa, B.A., El-gindi, D.M., and Abuleid, H.Z. (1964). Egyptian organic manures favor natural enemies of nematodes. Plant Disease Reporter. Vol. 48, No. 11. Reinmuth, E. (1955). Zur Biologie und okologie de kartoffel nematoden sowie Grundsatzliches zu sein Bekampfung. Dtsh. landw., Berl. 6: 6: Sitarmaiah, R and Singh R.S.(1978). Effect of organic amendments on phenolic content of soil and plant response of _.javanica and its host to related compounds. Plant and soil., 50 (3): Van der Laan, P.A.(1956). The influence of organic manuring on the development of the potato root-eelworm, Heterodera rostochiensis. Nematologica 2: Yeates, G.W. (1978). Populations of nematode genera in soil under pasture. Newzealand J. of Agric. Research 21: Yousif, G.W. and Badra T. (1981). Effect of some organic and inorganic amendments on hatching,infectivity and development of M. javanica.indian J. Nematol.11 (2), THIS RESEARCH IS SUPPORTED BY NARP GRANT CA /l99l. 11