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infested arabie land just before potatoes or red clover aa they suppress P. penetrana. Nematlcides give effectlve contro! oT P. penetraną but thelr co8t restrlcts thelr uae to land growlng valuable cropa. Other plant nematode relatlonahlp8 lndlcated by the resulta were that grass, red clover, oata, rye, and 8vede were e£flclent ho8t8 of Tylenchorhynchua dublua; red clover waa a good hoat o£ Rotylenchus robuatuą; potatoes were a bet ter hoat For rtelołdogyne .hapla than red clover, mangold or oat8; mangold was an e££lcient ho8t o£ P. neglectua but auppreaaed P. penetrana and F. crenatua; mangold and grasa were efflclent hosts of Paratylenchua app.

0813 RHOADES, H.L« & LINFORD, M.B., 1961. "A atudy o£ the paraaltlc habit of Paratylenchuą projectuą and P. dlanthus." Proceedlnga of the Helmlnthológical Soclety of Washington, 28 (2), 185-190.

0b8ervationa were madę on Paratylenchuą projectuą and P. dlanthus on the roots of clover and tobacco In ogar. Feedlng was malnly ectoparasitlc on root halrs and epidermal cells in the young maturę region. Pre-adult larvae of both apecies and males of P. dlanthus dld not appear to feed. Sooe larvae and females were seen to feed on one celi for several days. Inaertion of the atylet took several mlnutes and was followed by a period of relatlve lnactivity when sallva waa seen to flow forward from the doraal aide of the basal bulb to fili the 8allvary duet and ampulla. Sallva was not ob8erved paaalng through the stylet but a granular dome bullt up around the stylet during feedlng; thls appeared to have little effect on the celi contenta but protoplasta of red clover root halrs diaappeared after prolonged feedlng. A rhythmlc pulsatlon of the median bulb occurred some time after stylet lnsertlon and la8ted for morę than a week ln some 8peclmen8 untll the nematode was ready to retract ita stylet.

0814AN0N., 1961. "An alfalfa 8tem nematode (Dltylenchus dlpsacl) (Kuhn, 1857) Fllipjev, 1936)7* Cańadlan Inaect Pest Review, 39 (4), 165.

Infeatations of Dltylenchus dlpsacl were flrst reported on lucerne plots at the Research Statlon at Lethbrldge in 1950. No infeatations were noticed after 1952 untll 1958; sińce then lt has peralsted and has alao been noted ln several lucerne flelds in the area.

0815 BINGEFORS, S., 1961. "Stern nematodes ln clover8 and lucerne and thelr control by breedlng for resletance." International Grasaland Congresa (8th), Reading, July 11-20, 1960. Proceedlng8, pp.78-81.

Blngefors mentlons the racea of Dltylenchus dlpsacl that attack red clover, whlte clover and lucerne and the symptooa and apread of the dlsease in red clover cropa and dlscusses the lntroductlon of re8latant varleties into Sweden. The resls-tance of plants waa inereased rapldly by 8electlon but lt la not lnherlted aa a single gene. The reproduction of eelworma 18 lnhlblted ln reaistant varletlea and, sińce the number ln the soli decllnea when

a reslatant variety la grown, the lncldence of dlsease in a aubaequent ausceptlble varlety la reduced. In southem Sweden ln 1958, 80% of all the early red clover sown belonged to reaistant varletlea compared wlth only 10% ln 1939. Blngefors conalders that acreening plante for resletance ln the field 18 no longer rellable and must be replaced or supplemented wlth artiflclal lnfectlon methoda, probably using eelworms reared ln culture.

0816 McBRIDE, J.M., JOHNS, D.M. 6 CARTER, C.R., 1981. "Relatlve hoat responses of Interplanted weeda and com to Pratylenchus zeae and P. brachyuruą (Jtematoda, TyTenchida)." lAbstract of paper preaented at the 37th Annual Meetlng of the Southem Dlvlalon. American Phytopathologlcal Soclety.) Phytopathology, 51 (9;, 644.

Roots of varioua tranaplanted weeda, rep-resentlng 33 apecies, growlng wlth malze were sampled for Pratylenchus zeae and P. brachyuruą. The naize roots had PratyiencHuą lnfectlons of 30 to 200 per gm. and In weeds the lnfectlons were two to 14 per gm. The ratio of P. zeae to P. brachyurus in malze roots waa HTFT and Tn weeda roots 10:1. Roots of aeveral weed specles were not Infected and weeda that had infected roots were consldered to be uncongenlal hosta. There waa no evldence that the weed roots were antlblotlc to the nematode populatlons ln the malze roots.

0817TANASIJEVIC, N.,    1980. "PoJava 1

ra8pro8tranJeJe    nematode    stabla

(Dltylenchua dlpsacl Kuhn) na lucerkl u nasoj zemTJl.^TrZasKtita BilJa. Belgrade, No. 57/58, pp.225-227. (English aumnary p.227.1

A 8hort account of the dlstribution of Dltylenchus dlpsacl attacklng lucerne ln Vugoalavla ls given. Typlcal aymptoma of swollen stem, deformed crown buds and 8tunted growth are deacrlbed.

0818TOWNSHEND, J.L. & MULVEY, R.H., 1961. ^MAn occurrence of Heterodera trlfolll Goffart, 1932 ln the Niagara Peninsula, Ontario." Canadlan Plant Dlsease Survey, 41 (5), 290.

Cyat8 of Heterodera trlfolll were found in concentratlons of 35 and 40 per 200 gm. soli 8ample. LadIno clover was reported aa the ho8t crop.

*0818CHEN, T., KILPATRICK, R.A. & RICH, A.E.,    1962. "Stylet-bearlng nematodes

asaociated wlth whlte clovers in New Hampahlre 1960-1961." Plant Dlsease Reporter, 46 (5), 346-347.

Pratylenchus penetrans was found to be the predominant stylet-bearlng nematode ln and around the roots of whlte clover (Trlfollum repens) at two New Hampshlre (tl.S.A.) localltles. Populatlons of thls nematode were hlgher ln heavy loam than in flne sandy loam. Experlmental plots ln the two localltles were treated wlth (i) methyl bromlde, (11) dleldrin duat (50%), (iii) both Chemicals comblned, (iv) untreated control. Methyl bromlde gave good control for three years after the Inltlal treat-ment. High populatlons of P. penetrana were 198 found ln the dleldrin” treated plota,