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phenoxyacetic acld." Plant Dlsease Reporter, 47 (6), 497-501.

Test-tube experlments on the effect of Pratylenchus penetrans and 2,4-D on 7 varietles of lettuce (Lactuca satlva) and 6 specles of clover (Trłlollum spp.) are reported. Nematode Tnjury resulted In necrosis and svelllng of roots, stuntlng of plants and lncreased secondary root forma-tlon. Injury from 2,4-D caused stuntlng of plants, necrosis, malformatlon of roots and celi hypertrophy. The dlfference betwen nematode and 2,4-D Injury was observed only ln the early stages of growth. Seedllngs treated with callus tlssue contalnlng 2,4-D and nematodes whlch had been reared on callus tlssue, transferred sufflclent 2,4-D after thelr death to cause swe11Ing of roots and reductlon ln growth.

0772 CHEN, T. & RICH, A.E., 1963. "Attrac-tlon of Pratylenchus penetrans to plant roots.'* Plant Dlsease Reporter, 47 (6), 504-507.

White clover (Trifollun repens) seedllngs were grown under aseptlc condłtlons ln one limb of a U-tubę contalnlng 0.5% agar and Pratylenchus penetrans were added to the other limb. Wlthln5 hours sonę nematodes had mlgrated the 15 to 20 cm. to the root zonę. If clover was absent on elther slde or lf plants were present on both sldes the nematodes dld not mlgrate. The nematodes orlentated themselves towards the attrac-tant produced by the root and mlgrated towards it, both vertlcally and horizontal-ly. The concentration gradlents ln the agar are hlghest near the roots.

07 7 3 CHAPMAN, R.A., 1963. "Population development of Meloldogyne arenarla ln red clover." Proceedings of the Relmintho-logical Society of Washington, 30 (2), 233-236.

The ratę of population development of Meloldogyne arenarla ln red clover growlng ln 80li lnfested wlth 500 larvae per 500 gm. was greater than ln plants growlng ln soli lnfested with 100 larvae per 500 gm. Thls Indlcates a dlrect relatlonshlp between the lnfestatlon level and popula-tlon development of M. arenarla ln red clover. The former set~óf plants, l.e. that with the hlgher lnfestatlon level, was lnjured by the nematodes whereas the latter was not. A slgnlflcant stlmulatlon of root growth ln young plants occurred at the hlgher lnfestatlon level.

07 74 GOLDEN, A.M. A COBB, C.S., 1963. ^,rHeterodera lespedezae (Heteroderldae), a ńew specles or cyst-formlng nematode.'* Proceedings of the Helminthological Society of Washington, 30 (2), 281-286.

Heterodera lespedezae n.sp. (20 femalea, małe unknown), coliected from roots of Kobe lespedeza, Lespedeza strlata, near Monroe ln Union County, North Carolina, U.S.A., is deseribed and flgured. The common name of "Lespedeza cyst nematode" is suggested for thls specles. It is sald to be closely related to H. trifolll, but differs ln havlng shorter stylets in both larvae and females, the outlet of the dorsal oesopha-geal gland near the style t base, by differences in the generał shape of the larval tali and by the stylet knobs sloping

posterioriy and measurlng 5 mlcrons ln wldth ln the female. It differs froo H. glyclnes in the absence of males, ln havlng a zonger larval stylet, and in the length of the larval tali in hyaline tali terminal. The larval tali terminal ls also relatlvely narrower and has an almost acute termlnus.

0775 NORTHERN IRELAND, AGRICULTURAL RESEARCH INSTITUTE. Forty-elghth Annual Report 1974-1975. Hlllsborough, Co. Down; (1975) 49 pp. [En, Plant Nematology pp. 17, 18]

The effect of Heterodera trifolll lnfestatlon on the growth of red (Trlfollum

Sratense) and white (T. repens) clovers in orthem Ireland is belng studied. Mentlon ls madę of the role of Dytllenchus dlpsacl ln reducing red clover yields.

07 76 HOLTZMANN, O.V. & ARACAKI, M., 1963. ⁿClover cyst nematode ln Rawali." Plant Dlsease Reporter, 47 (10), 886-889.

The authors report the flrst record of a cyst nematode ln the State of Hswall. Heterodera trifolll was found attacklng Tri fol lup" repens ln pastures and on road-sldes in severai dlatrlcts. In pot tests, uslng an lnoculum of 10 non-deslccated cysts or gravld females of the nematode, Beta yulgarls var. cicla, Lathyrus tlngltanus, Sesbanla grandl flora and Yrltollum semlpilosum were found to be very susceptlble; Brasslca juncea, Deemodlum c ani mim, D. unclnatum and t oma to wre slightly susceptlble. Ali these are sald to be new host records. Pathogenlclty testa showed the yle Id of Trlfollum repens inoculated with H. trifolll to be reduced 8everely after tfie flrst 2 months' growth, as compared with uninoculated plants. The authors dlscuss earller records of Heterodera ln Hawall, whlch may posslbly have referred to a specles of Meloldogyne. H. trifolll appears to be a potentially serlcrus pest in Hawall.

07 77 LEACH, C.M., DICKAS0N, E.A. & GROSS, A.E.. 1963. "The relatlonshlp of insects, fungl and nematodes to the deterioratlon of roots of Trlfollum hybridum L.ⁿ Annals of Applied Biology, 52 (i), 371-385.

The posslble relatlonships of lnsect, ftingus and nematode injury to the deterioratlon of roots of alslke cIover, Trlfollum hybridum wre lnyestlgated. Randami red plots with slxfold repllcstlon of the followlng treatments and thelr comblnatlons wre used: (1) the lnsectlclde heptachlor (at 4 Ib. per acre) sprayed on to the soli surface and rototllled to a depth of 4 Inches; (li) the soli fumlgant chloropicrln (at 450 lb. per acre) applied by chlsel harrow to a depth of 8 Inches and sealed by rolling; (lii) the nematlcide EDB (at 6 gallons of Dowfume W-85 per acre) applied as for chloropicrln. Ihe plots wre sown with clover seeds 2 weks after treatment. The insectlclde together with elther of the soli fualgants lmproved stand unlformity, plant helght and flowrlng and decreased the number of weeds. In the second year thls treatment greatly lncreased the dry-wight yleld. Both Meloldogyne incognlta var. acrlta and Pratyienchu8 sp. wre pre-192 sent but only very few of the former. No