Indian J. Nema/ol. 4 (1974) : 31-45

EFFECT OF SOME PESTICIDES ON NEMATODES ASSOCIATEDWITH BRINJAL AND TOMATO

BY

INDERJIT SINGH and S. K. PRASAD

DivisiJn of Nematology, Indian Agricultural Research Institute, New Delhi, India

The relative efficacyof some pesticides viz., thionazin, phorate, lindane, dimethoate,DBCP, carbofuran and thionazin+phorate was tested against nematodes associated with brinjaland tomato. Experiments with dazomet were conducted separately. Thionazin, phorate anddazomet were used as dip/granule/dip+granule application. Lindane, dimethoate and DBCPwere used as dip application; and carbofuran and thionazin+phorate were used as granularapplicat.on. In each application there were four dosages. The observations were recorded inrespect of nematode populations, plant growth characters and galls per plant. The higher dosagesof dip+granule application of thionazin, phorate and dazomet; and granular application ofthionazin, phorate, dazomet, carbofuran and thionazin+phorate were effective. Dip+granuleapplication showed smaller galls when compared with those obtained in granular application. Ingen.:ral, thionazin, phorate and dazomet were effective as granular and dip+granular application;and carbofuran and thionazin+phorate as granular application. While phorate formulations weremore effective in case of brinjal it was thionazin applications in respect of tomato.

Brinjal and tomato-widely grown and commercially important vegetablecrops are most susceptible to plant parasitic nematodes. The seedlings normally getinfested in the nursery seed bed and when transplanted and given optimum condi­tions for plant growth, which are also most favourable for nematodes, the popula­tion of plant parasitic nematodes builds-up rapidly and cause injury to plants. Inthe present studies attempts were made to evaluate the effectiveness of some pesticideswhich could be used economically either as a seedling dip treatment and/or granularapplication in reducing the nematode-induced crop losses.

MATERIALS AND METHODS

Nurseries ef brinjal (Solanum melongena - variety Pusa Purple Long)and tomato (Lycopersicum esculentum - variety Pusa Ruby) were raised on methylbromide (1 kilogram per 9 sq. metre) treated beds. Seedlings of uniform size andage (28-30 days) were used for transplanting. Studies were conducted in the monthof September. Pesticides studied included: thionazin (Nemafos, 0,0 - diethyl0-2 pyrazinyl phosphorothioate) lOG, 46% E. C. ; phorate (Thimet, O-O-diethyl S-

32 INDERJIT SINGH AND S. K. PRASAD

(ethylthiomethyl) phosphorodithioate) lOG, 90% technical grade; lindane (Gam­mexane, Gamma isomer of I,2,3,4,5,6-hexachlorocyc1ohexane - at least 99% thegamma isomer of BHC (Benzene hexachloride); dimethoate (Rogor, O,O-dimethylS-(N-methylcarbamoyl methyl) phosphorodithioate) 30% E.C.; DBCP (Nemagon,1,2-dibromo-3-chloropropane) 75% (V/V) ; Carbofuran (Furadan, 2, 3-dihydro-2, 2­dimethyl-7-benzofuranyl methyl carbamate) 10 G, and thionazin+phorate (mixture)lOG. Thionazin and phorate were used as dip/granule/dip+granule application.Lindane, dimethoate and DBCP were used as dip applications, and carbofuran andthionazin + phorate as granular applications. In each case, there were fourdosages, which were replicated three times. The details are given in Table I(brinjal) and Table 11 (tomato). Different concentrations of thionazin (46% E. C.),dimethoate (30~~ E. C.), and DBCP (75% V/V) were prepared by diluting themwith water. Phorate and lindane concentrations were prepared from 10 per centstock solutions with emulsified water (Triton x 100, 1 part in 160 parts of tapwater).

For selecting the highest dip concentration not phytotoxic to seedlings, apilot experiment was conducted. Concentration time combination giving phyto­toxic effects were discarded. Based on the highest concentration with no phytotoxiceffect, three lower concentrations of each pesticide were selected.

Sandy loam soil, heavily infested with plant parasitic nematodes wascollected from the Horticulture DivisIOn, Indian Agricultural Research Institute,New Delhi. For pre-treatment nematode counts, three soil samples each con­taining six cores were taken. From this, 200 ml was processed for nematodeextraction by "Cobbs modified sieving and Baermann funnel technique" (Christieand Perry, 1951). Nematode numbers in 0.92 kg (soil/pot) of soil was computedas follows-Brinjal : Meloidogyne larvae 312, Tylenchorhynchus 1230, Rotylenchulus327, Helicotylenchus 123, Trichotylenchus 96 and saprozoic nematode 3264;Tomato: Meloidogyne larvae 378, Tylenchorhynchus 1209, Rotylenchulus 663, Hoplo­laimus 12li and saprozoic nematodes 2643.

After the dip treatment, seedlings were transplanted in 15 cm diameterearthen pots. In the case of granular applications the pesticides were placed inholes (in the centre of the pot), which were filled up and pressed firmly. In case ofdip + granular application, the required quantity of granular formulations wasadded as indicated earlier and the treated plants were transplanted. For control,seedlings were transplanted after giving a dip in emulsified water for 15minutes.

TABLE I

Effect of some pesticides on nematodes and plant characters (brinjal experiment)Nematodes

Plant characters

Dosage AI/ha (kg),

Observations after 50 daysObservations

Observations after 50 daysTreat- concentration (ppm)after 30 days

ment No.and time in

minutes ShootRootShootRoot

Meloidogyne Tylenchor-

Rotylen-SaprozoicShoot lengthlengthlengthdrydryhynchus

chulus weightweighttI1

(cm)(cm)(cm) .."

(g) (g).."tI1n>-l

2345 6789101l 0

'TJ."tI1ThionazintI>

>-l

Dip

n8tI1Tt

125 (15 minutes)576110951220699.515.036.72.81.2{Il

0T2250 ("") 683 157932028809.515.830.02.81.0z

Ta500 ("") 384 1088107334910.818.527.54.41.1z

tI1T,1000 ("") 448 768170221911.821.728.32.31.0t!:

>>-lGranule0

CltI1T55 235512234228310.416.730.02.00.6{Il

T6

11 128341320172812.519.841.73.01.1

T,

16 1703202132901-12.718.341.04.5lATa

22 106235171187714.221.336.75.41.7

Dip + Granule Tu

1000 (15 minutes>+ 5171576277471510.512.722.32.00.4

Tto

1000 (""

>+11128 213277198411.017.335.33.00.9

Tu1000 (""

)+16 85 171128185612.719.027.35.11.1

Tt!1000 ("

")+22 64 85171209112.519.030.75.61.2ww

23456 78910 11w~

PhorateDipTu

125 (15 minutes)533142732028379.216.025.72.00.8

Tu

250 ("") 469 1301107403210.318.350.73.71.2

Tu;

500 ("") 512 1963234422411.220.338.35.71.6

Tl61000 ("

") 533 2048192576010.717.729.75.11.9

Granule•..Tl7

5 46944834119209.718.324.03.41.1ZgTl8

11 149149320219710.316.324.03.00.7"Tl9

16 646485130111.220.329.35.91.7...•

•....,T20

22 430074711.219.328.37.21.7v.>

ZDip + granule0

::r::Tu1000 (15 minutes)+ 514927753320278.516.028.7l.S0.4>

T221000 ("

")+11149 14938420275.511319.72.70.3

Z0T28

1000 ("")+16 85 436411736.216.323.35.70.6~T24

1000 ("")+22 43 0434917.817.028.05.01.1~

Lindane

~Dip

>uo>

Tu500 (15 minutes)299130125627617.814.329.03.31.40

T28

1000 ("") 341 149329932858.015.329.72.71.4

T272000 ("

") 213 177117120698.715.328.74.01.6T28

4000 ( "") 213 260312828169.216.722.05.01.6

Dimethoate DipT29

125 (15 minutes)3412688299422411.219.732.74.41.6Tao

250 ("") 341 245327734999.017.029.03.71.1

Tal500 ("") 341 358432040758.319.331.75.61.6

Tal1000 ("

") 256 377634150137.819.328.06.72.3

DBCP

DiPTal125 (15 minutes)4691280363505610.827.727.~2.70.7

Tu

250 ("") 491 1429299366913.027.723.03.51.2

TaG

500 ("") 363 1301299712512.027.022.73.41.0

Ta.1000 ("

") 235 960256124379.820.725.33.00.7

CarbofuranGranuleTa7

5 19236343874710.018.726.32.40.6

TaB

1 128363055277.816.330.01.80.6

Ta9

16 85149068697.019.332.02.70.7trI..,T40

22 4364039477.822.032.74.51.1..,trI()

Thionazin+phorate

>-l

0Granule..,

Tfl

5 51212164271070910.728.726.73.81.5"tl

menT'211 2131365405808510.522.724.04.81.5>-l

Ta16 641711491102911.030.326.76.51.5B

ClTu22 212351281075212.7!0.338.08.52.4men

T,sControl 4912304469103897.517.327.02.30.50Z

For thionazin andphorateZ

S. E.N.S.N.S.N.SN.S.0.2N.S.N.S.0.3N.S.

trI

s::C. D. (P=0.05)

N.S.N.S.N.S.N.S.0.4N.S.N.S.0.5N.S.>-

dC. D. (P=O.OI)

N.S.N.S.N.S.N.S.0.5N.S.N.S.N.S.N.S.0mFor dosages

en

S. E.

131.2592.6117.81581.40.72.26.80.9 0.4

C. D. (P=0.05)

261.11179.4233.93147.11.44.313.51.90.7

C. D. (P=O.OI)

345.11558.6309.84159.2t,>5.717.82.51.0

For lindane, dimethoate. DBCP, carbofuran thionazin+phorate and a/so for applicationsS. E.

65.3296.358.2790.40.41.13.40.5 0.2

C. D. (P:0.05)

129.9589.7115.71572.90.72.26.70.9 0.4

C. D. (P •••O.Ol)

171.7779.3153.22078.70.92.88.81.20.5wVIN. S.=Non significant, Average of 3 replications

TABLE IIwEffect of some pesticides on nematodes and plant character (tomato experiment)

0'1

Nematodes

Plant characters

Dosage AI/ha (kg)

Observations after 50 daysObservations

Observation after 50 daysTreat- after 30 daysmeot

concentration (ppm)

No.

and time in

minutes ShootRoot

ShootRoot

Meloidogyne Tylenchor-

Rotylen-SaprozoicShoot lengthlengthlengthdrydry

hynchllschllllls

(cm)(cm)(cm)weightweight(g)

(g)Z02345678910Il r!l

it'.......>-lThionazintIl

Dip

ZClTl

125 (15 minutes)38425814395979220.030.327.61.60.8-..•..

Ta250 ("") 341 9172901392524.336.030.71.71.2>Z

Ta500 ("") 341 9392048503518.833.327.32.51.00

Ta

1000 ("") 213 576917514119.837.023.72.40.6:n

Granule

;00:

'1:iTi

5 2354912048448015.828.718.01.606 it'>To

11 1923411344546118.330.319.02.10.6tIl>T7

16 1923851365347724.540.323.02.91.30

Ts

22 85171960433121'049.321.33.50.7

Dip+granule Te

1000 (IS minutesH 5 256 6832923469322.533.326.62.20.6

TIO

1000 (""

)+11149 2341941448017.029.730.72.50.6

Tu

1000 (""

)+16174 4271216268821.535.727.7. 2.90.7

Tu

1000 ("")+2285 3841536390420.240.736.03.80.8

Phorate DipT18

1 (5minutes)6615761771503511.724.022.81.20.3

Tu

2 ("") 5J2 640J941695510.730.324.72.40.7

TI5 5 ("") 320 6832261586713.327.026.02.10.6

TI6

10 ("") 299 4911941499216.336.024.33.01.1

Granule TI7

5 6405761813309321.032.827.72.10.6

TI8

II 2353631600401120.531.027.32.40.7

TIe

16 107448469260312.432.021.32.80.6

T20

22 149554277145114.633.825.34.10.7

Dip+granule T2l

10 (5 minutes)+ 5405363917273113.331.317.22.40.3~Tu10 ("" )+112134271173411712.827.622.02.30.4>rj

>rj

T2a10 ("" )+161923201003266716.236.327.32.40.7~(')

T~410 ("" )+222354051131537615.832.431.33.00.9>-l

0Lindane

>rj

"l:IDip

~'">-l

T25

12 (5 minutes)34112371515556822.521.08.81.40.2(5

8T2825 ("" )256 7681813584522.333.024.71.90.4~'"

T2750 ("" )1924481332526917.126.019.31.30.40

T2.

100 ("" )1074911771469319.534.723.31.60.7Z

ZInDimethoatea::>Dip

>-l0T2e

1 (5 minutes)128012162923546119.234.323.02.00.6tl

~'"Tao2 ("

") . 405 5761408531219.532.319.32.10.6

T31

5 ("") 448 5331387622921.547.326.33.31.1

Tat

10 ("") 469 6191387569621.739.727.72.81.2

DBCP DipTaa

125 (5 minutes)1067234717281107221.731.720.71.50.5

Ta4250 ("

") 789 14291515695519.629,320.01.40.6

Tu500 ("

") 512 21331387844821.831.725.32.01.1

Ta81000 ("") 533 21551579520516.333.720.72.20.8~

-:J

2 3456 7891011w00---_ ... ,~_ .. _-

--~~_._- ~.~._--~

Carbofuran GranuleT87

5 81121332005644322.123.012.01.50.2

T38

11 49114932304516322.327.718.71.60.8

Tall

16 70413012027578118.334.023.73.70.9

T40

22 21311091323544021.737.710.33.71.2

Thionazin+ phorateGranule

ZT.1l

5 76822831920475717.231.325.71.60.5t:l"'T42

11 87518561365441617.628.022.01.50.3:oll

...•

T4316 38418561642313617.440.727.33.50.7;:j

tI:IT44

22 2561515619266728.742.022.74.11.352

T45

Control 100321551728554713.222.718.71.30.5Cl

:rFor thionazin andphorate

>Z

S. E.N.S.N.S.279.7N.S.1.21.6N.S.N.S.N.S.

t:l

~C. D. (P=0.05)N.S.N.S.556.8N. S.2.33.2N. S.N.S.N.S.r:C. D. (P=O.Ol)N.S.N.S.N. S.N. S.3.1N.S.N.S.N.S.N. S."=:ollFor dosages

>tI:I

S. E.219.5575.4970.31662.74.15.74.00.80.3

>0

C. D. (P=0.05)437.11145.01930.93308.88.111.37.91.60.6

C. D. (P=O.OI)

577.31513.02551.74373.110.714.910.52.10.8

For lindane, dimethoate, DBCP, carbofuran, thionazin+phorateand also for applicationsS.E.

109.4287.4485.1831.62.42.82.00.60.2

C. D. (P=0.05)

217.6571.5965.11654.44.15.64.01.10.3

C. D. (P=O.OI)

288.0755.81276.12186.25.47.45.21.50.4

N. S. = Non significant, Average of 3 replications

EFFECT OF PESTICIDES ON NEMATODES 39

Thirty days after transplanting, the height of plants were recorded. Afteranother 20 days, the plants were depotted and soaked in two litres of water in abucket. The roots were carefully freed from the adhering soil, and the soil wasmixed thoroughly. From this soil suspension, 500 ml was processed for nematodepopulation. Nematodes present were then interpreted as population per pot(0.92 kg soil). Shoot and root length, shoot and root dry weight and number ofgalls per plant were recorded. In case of tomato, yield per plant was also recorded.Shoots and roots were dried in paper envelopes in an oven at 80°C until the weightbecame constant and the dry weights were recorded.

Separate experiments with dazomet (My lone, 3,5-dimethyl1etrahydro­1,3,5, 2H-thiodiazine-2-thione) 99% were· conducted with brinjal (variety-PusaPurple Long) and tomato (variety-Pusa Ruby). Soil was collected from vegetablearea of Agronomy Division, Indian Agricultural Research Institute, New Delhi.Pre-treatment nematode population counts were made as reported for the previousexperiments. Population counts in 0.92 kg of soil was as follows: Meloidogynelanae 518, Tylenchorhynchus 1868, Hoplolaimus 112, and saprozoic nematodes3953. Pots of 15 cm diameter wele used. Dazomet was used as dip/granule/dip+granule, each at four dosages. The details of the treatments are furnishedin Table III (brinjaJ) and Table IV (tomato). Each treatment was replicatedthree times. The procedures followed and observations recorded in theseexperiments were similar to the one reported earlier with the exception that shoot­length was not recorded after 30 days of transplanting and yield in respect of tomatowas also not obtained.

RESULTS AND DISCUSSION

Nematodes predominantly associated were: Meloidogyne (M. incognitaand M. javanica), Tylenchorhynchus (T. brassicae) and sparozoic nematodes.Rotylenchulus reniformis was also present in large numbers except in the case ofdazome[ experiments. Hoplolaimus and Helicotylenchus were present in lownumbers. A few Trichotylenchus was also recorded in case of brinjal experimentexcept in the case of dazomet trials. The results in respect of nematodes and plantcharacters are furnished in Table I and III (brinjal), and Table 11and IV (tomato).The number of nematode galls have been shown in fig. 1 (brinjal) and fig. 2 (tomato),and tomato yield in fig. 3.

In case of brinjal, the best results were obtained with dip + granule ofphorate. It was followed by granules of phorate and carbofuran, dip + granule ofthionazin, granule of thionazin and thionazin + phorate in that order. The leasteffective ones were dip of DBep, dimethoate and phorate.

40

;,o.

".I.

' • .1.

' • .1.

INDERJIT SINGH AND S. K. PRASAD

~.•"o~~"

~... J

.£1, 3<.• Z

'.1 C""======~~===== :

...=~t"J. ~

noJ.1 :1•.1.11111" 1I'"1!I1I1I1I11I111111111 "

0..1.= ..~~MII'IIIIIIIIIIIII~:~'IIII j

!..czoi~

I"l1

.."

.,.,I"l1

(")..,C.."

'tItT1'"..,(=i

6tT1'"ozZI"l1

a::>...,ooI"l1v.

DlP+GRANUt..£

IIlIl '" 41 '"

~~~.~ Ii':"~.. L'

, ~•

• - "" 0>0.•... .,:-

~: ' ~~GRANULE .ofP

L-- 01010•••£1-----

•.

d':'d,!J. .-~ •..

GRANULE -DIPHilMULE DIP DIP Oftl GRANULE GRANULE

P 1-10RATE ...,..-----J t. LIND"'NE~tDfMETHOATEtt...DeCp...Jtc.ReoFUA.~THION,tJIN-f.PHORATE

....~

Fig. 2. Effect of some nematicides on the intensity of root-knot nematode galls on tomoto,

GRANULE DtP+GRA"'ULE DIP

THIO •••/I,IIN ~t.-o,p'---

60

.0~z~A

..

l' I tMIl1l g..

""ooj d {E; •••• do!'

~. :? ~ ~ ~ ~ 5 ::: ••:::

~ >.oj d·,::!~":: d d~~ ..~ ;..~..~ 0· .... ~ d·~·~~~ ;! ~;! •... ~•. (ltt t-:? .Z f t11:.' , .i 0- Ki! _\ .

OtP GRANULE Dtp+GAAHVLE DI.P GRANULE DtP+GAAJIJlE DIP OIP Dtp GRAN.VU .GRANULE

~THIONA1IN_______J ~ PHQRA T E'~ '-llN'DANE.tfOI-..:.TtiCJM[' LOICP...JtC"I!IOf:lAlANtlTHIOP\lAZIN"., - p~rE~

:j[~

~ '".• .•.•.•.•......•••'It400i : .~.~.....~•~ ~~.... :;.!;.".

~

. Ir ~ 'DO;

, .•~ ".

: f

'"•. ' ~~"' .• ': ~

[lEISo!0200 ?

~ t='.=.. ...,~ •• :.=-','NI;·.~ .•-...

"~ ,: {:It D._I_IIlI ,,-...•'..

' ..

Fig. 3. Effect of some nematicides on the yield of tomatoA

42 INDERJI r SINGH AND S. K. PRASAD

TABLE III

l:.Jfect of dazomet on nematodes and plant character (brinjal experiment)

Nematode

Plant charactersDosage AI/ha Treat-

(kg), and con-ment

centration (ppm)Shoot

RootShootRootNo.

and time inMeloi·Tylenchor- Saprozoiclengthlengthdrydryminutes dogynehynchus

(cm)(cm)\\ eightweight

(g)(g)

GranuleTl

111 61944371181913.721.02.10.7

T2

223 2133136955711.720.02.51.0

Ta

335 171533375517.024.03.61.7

T.

447 21747465117.029.05.11.6

DipTi

625( 10 minutes)12804629947211.717.31.50.8

Ta1250 ("

") 17924437872511.714.3l.20.7

T72500 ("

") 1700460893659.015.01.30.5

Ts5000 ("

") 8113556812811.014.01.70.7

Dip + GranuleTs

5000 (10 rninutes)+l11 405 2624691212.016.71.50.6

T105000 ("

")+223 427 27951026114.723.03.61.1

Tu5000 ("

")+33597875540914.024.03.30.7

T125000 ("

")+44743853294414.722.04.41.0

T]3

Control24]15355955710.716.71.10.3

For applicationsS. E.

138.1527.9N.S.1.12.20.30.1

C. D. (P=O.05)

284.01085.3N.S.2.34.60.70.3

C. D. (P=O.OI)

383.81467.0N.S.3.16.20.90.4

For dosages S. E.

276.21055.82602.72.24.50.70.2

C. D. (P-0.05)

567.92170.65351.24.69.21.40.5

C. D. (P=O.OI)

767.62933.97232.96.212.41.90.7

N. S. = Non-significant, Average of 3 replications

EFFECT OF PESTICIDES ON NEMATODES 43

TABLE IV

Effect of dazomet on nematodes and plant characters (tomato experiment)

Nematodes

Plant charactersDosage AI/ha Treat-

(kg), and con-ment

centration (ppm) ShootRootShootRoot

No.and timeMe/oi-Tylenchor- Saprozoic drydry

in minutes dogynelengthlengthweightweighthynchus (cm)

(cm)(g)(g)

Granule

Tl

111 74753912107732.724.31.30.8Ta

223 21320401834737.724.33.00.9

Ta

335 25615301986135.719.74.40.8

T4

447 43171289940.724.03.71.1

DipT5

312 (5 minutes)292888111611916.019.71.50.5Ta

625 ("") 219679051244336.321.01.90.7

T71250 ("

") 213363151350431.325.02.20.9Ta

2500 ("") 9827019923534.329.72.10.9

Dip + GranuleTg

2500 (5 minutes)+lll 68374672107743.027.33.01.1TID

2500 ("")+223 171 23681815543.327.03.90.9

Tu2500 ("

")+335 107 384275239.722.33.50.9

T122500 ("

")+44743213245143.322.73.00.8TI3

Control18756293921631.319.31.30.4

For applications S. E.

259.9889.42128.02.6N.S.0.2N.S.

C. D. (P-0.05)

534.41828.64375.15.3N.S.0.4N.S.C. D. (P=O.OI)

722.32471. 7N.S.7.2N.S.0.6N.S.

For dosages S.B.

519.81778.84255.95.24.20.40.2C. D. (P=0.05)

1068.83657.38750.210.68.70.90.5

C. D. (P=O.Ol)

1444.64943.411827.214.3N.S.1.20.6

N. S.=Non significant, Average 3 replications

44 INDERJIT SINGH AND S. K. PRASAD

In case of tomato, dip + granule of thionazin was most effective. Itwas followed by granule of thionazin, dip + granule of phorate, granule of phorate,thionazin + phorate and carbofuran in that order. The least effective ones weredips of phorate, dimethoate, thionazin and OBCP. The difference in the effectivenessof dip + granule of phorate may be attributed to the low concentration of dipapplications.

In case of dazomet, the dip application were least effective. The orderof effectiveness was: dip + granule = granule > dip. The high toxic potency ofdazomet against nematodes has also been observed by Burgis & Overman (1956)and Nirula & Bassi (1965).

The higher dosages of dip + granule application of thionazin, phorateand dazomet ; and granular application of thionazin, phorate, dazomet, carbofuranand thionazin + phorate were effective. There was no complete elimination ofgalls. Oip + granule applications, however, showed smaller galls when comparedwith those obtained in granular applications.

The dip application at higher concentrations registered a lower populationof Meloidogyne over control in case of brinjal. This was not true for tomato.This difference could be ascribed to the higher concentrations (phytotoxic in case oftomato) used in the case of brinjal. Similarly, preplanting dips with thionazin(Sher, 1960; Miller & Perry, 1965 and Reddy & Seshadri, 1972), phorate (Sher,1960) and OBCP (Oecker, 1970) have been found to be effective in minimisingnematode-induced crop losses. However, present findings are not in agreementwith those of Bindra & Kaushal (1971), where they reported that a pre-plant dip ofdimethoate 0.05% for 6 hours was most effective in supp~essing the root-knotnematode, Meloidogyne incognita. This concentration and time combination wasfound phytotoxic to tomato seedlings. Also, dimethoate dips did not give promisingresults.

In respect of Rotylenchulus reniformis, best results on brinjal wereobtained with higher dosages of dip + granule of thionazin and phorate, andgranular application of carbofuran, phorate, thionazin and thionazin + phorate.Also, the higher dosages of dip application of thionazin, phorate and lindane hadregistered low numbers over control. This was not true for tomato and could beattributed to difference in dip concentrations and the host plant. The difference ineffectiveness of different nematicides against different plant parasitic nematodes ondifferent hosts are in agreement with SincJair (1968).

In general, thionazin, phorate and dazomet were effective as granular

INDERJIT SINGH AND S. K. PRASAD 45

and dip + granular applications; carbofuran and thionazin + phorate as granularapplication.

ACKNOWLEDGEMENT

The authors are grateful to Dr. A. R. Seshadri, Head, Division ofNematology, Indian Agricultural Research Institute, for providing the facilities.

REFERENCES

BINDRA, O. S. & KAUSHAL, K. K. (1971). Chemical root-dips for control of root-knot nematodeattacking tomato. Pans 17 : 453-457.

BURGIS, D. S. & OVERMAN, A. J. (1956). Crop production in soil fumigated with Crage Myloneas affected by rates, application methods and planting dates. Proc. Fla. St. Hort.Soc., 69 : 207-210.

CHRISTlE, J. R. & PERRY, V. G. (1951). Removing nematodes from soil. Proc. helminth. Soc.Wash., IN ; 106-108.

DECKER, H. (1970). Further investigations on the control of parasitic nematodes in Banana plantmaterials. Xth International Nematology Symposium of the European Society ofNematologist, Pescara (Italia), 8-13 Sept., 1970 pp. 162.

MILLER, H. N. & PERRY, V. G. (1965). Elimination of nematodes from nursery plants by chemicalbare root dips. Plant Dis. Reptr. 49 : 51-53.

NIRULA, K. K. & BASSI, K. K. (1965). Observations on the control of root-knot nematode,Meloidogyne incognita (Kofoid and White, 1919) Chitwood, 1949, with Mylone andNellite. Indian J.Ent., 27 : 368-369.

REDDY, D: D. R. & SESHADRI, A. R., (1972). Elimination of root·knot nematode infection fromtomato seedlings by chemical root dips or soil application. Third InternationalSymposium on Sub-Tropical and Tropical Horticulture, Bangalore (India) Feb. 7thto 14th (Abstract) : 155.

SHER, S. A. (1960). Chemical control of plant parasitic nematodes in plant roots (Abstr.) Phyto­pathology, 50 : 654.

SINCLAIR, J. B. (1968). Fungicide-nematicide tests: Results of 1967-Baton Rouge. La : AmericanPhytopathdlogicalSocietY,23 : 148.

Accepted for publication: 18 June 1974