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bi-monthly from June to October. Large numbers of Pratylenchus penetrans were found at 4 of the sltes; at the 5th site P. crenatus vas the most numerous. The popula-tlon oT Pratylenchus spp. In the roots lncreaeed 3 to 7-fold during the growing aeaaon. TYlenchua spp., HelIcotylenchua spp. and Aphelenchus sp. were also lound consistentTy Iii email er numbers together with occaslonal Paratylenchus spp., Tylenchorhynchus spp., Xlphlnema app. and heterodera spp." The total populatlon of plant-parasltlc nematodes was Inltlally high, decreased rapidly and then built up steadily to the end of the growing season.

0794 PAŁO, A.V., 1962. "Translocation and development of stem eelworn, Dltylenchus dlpsacl (Kuhn) in luceme, Medlcago satjyą L. Nematologlca, 7 (2), 122-1327 iGeroan susasary pp.131-132.1

Pało glve8 the resulta of experiments on the ecology of the lucerne sten eeIwona. Two-week-old lucerne seedllngs (Du Puits vaTiety) were Inoculated with 200 eelworms (all stages) and, on later exasalnation, eelworm8 wre found in all parte of one-month-old plants; the second and third-month-old plants showed irregular infection In the maln stem and Infectlons in the side shoot8 appeared to be independent of the position of the main stem infection. EelwortDs are carried in the flower debris and not within the seeda thejnselves and are aiso carried up passively as the plant grows. The viability of narclssua, tulip and lucerne races In drled plant materiał decreased as the humldlty at which they were stored lncreaeed. Lucerne seedllngs grown for 2 months in pots of artlflclally lnfested soil decreased In wlght by 10.2 mg. for each 10-fold increase In lnoculum and also there was 28-fold Increase in finał eelworiB populatlon ln the plant for unit increase in the inltial Inocultm. Ten eelworss scattered at random over 120 aq. cm. surface of 1 kg. of potted soil was sufflclent to cause serlous Infection of the seedllngs. There was no evidence of parthenogenesis.

0796RIGGS. R.D., DALE, J.L. 6 HAMBLEN, M.L., 1962. ^,rReaction of Bermuda grass yarietles and lines to root-knot nematodes. ^,rPhytopathology, 52 (6), 587-588.

Ten posturę typea and 6 lawn types of Bermuda grosa (Cynodon app.) were tested against the root-lcnot nematodes Meloldogyne arenarla. M. bagla, M. Incognito. M. Incognito vair. acrlta and M.~ 1avanlća. Tfje most damaging was M. lncognlta var. acrlta. reslstance be Ing showfTinone lawn and U posturę types. M. hopla did least damage, galis with egg massisbeing found on only 4 of the pasture types. Coastal and Midland were the most reslstant of the pasture types, Midland belng at tackę d only by the M. lncognlta group. Uganda was the best Tawn type, only M. lncognlta var. acrlta cauaing a few galfs, but no egg masses were found.

0796ROIVAINEN, 0., T1NNILA, A. 6 KANERV0,

V., 1962. ⁿ0bservatlons on the stem nema-tode Dltylenchus dlpsacl (Kuhn) Pllipjev as a pest of red clover in Flnlsnd." Annales Agriculturae Fenniae, 2, 127-132.    195

Dltylenchus dlpsacl has been found ln red clover at <T different places in Flnlsnd where It was shown that the nematode could be spread by seed. Mechanlcal cleanlng of nematode-lnfested red clover seed reduced the degree of infestatlon but all nematodes were not removed. It is recommended that lmported red clover seed should be treated with oethyl bromide.

0797SASSER, J.N., YARGAS GONZALES, O.F. 6 MARTIN, A., 1962. "New flndings of plont-parasitlc nematodes in Peru." Plant Disease Reporter, 46 (3), 171.

Plant-parasitic genera encountered in Peru by Krusberg & Hirschmann, 1958 Ifor abstract see Heim. Abs., 27, No.l43e] were agaln found in a survey madę in 1961. New flndings included Dltylenchus dlpsacl on lucerne, Rotylenchulus renlformie ln large numbers fromsoTT from the rhizospheres of 8everal crop plants, Radopholus simllis causlng severe damage in banana plantatlons and a Pollchodorus (undescribed species) aseoclated with i“ mahogany tree. In the Coastal region Meloldogync lncognlta and R. simllis were the most łmportant economlcaT-ly, causlng severe damage to cotton and banana respectlvely, and there was evidence of an interrelationship between these nematodes and certain fungal diseases. In some areas Heterodera rostochlensls caused severe losses to potato and ln one area of the selva M. exlgua on coffee was the most damaging nematode.

0798 ALIEV, A.A., 1961. llnfectivity of Meloldogyne sp. to »arieties of maize.] Trud i V8e8oyuznogo Instituta Zashchitl Rasteni, No. 16, pp.89-92. lin Russian: Engllsh summary p.92.]

Two-year observatlona on 29 maize variet-ies, planted in soli heavlly infected with Meloldogyne sp., showed that different va-rletles became infected to different degrees but that developoent and fruiting of the plants wre unaffected.

0 79 9 00STENBRINK, M.,    1960. "Einige

Grundungunsfragen im Hinblick auf pflanzen-parasltare Nematoden." International Congress of Crop Protectlon (4th), Hamburg, September 195*. Proceedlngs, Vol. I, pp.575-577. [Engllsh summary p.577.J

Red clover, Trlfollum pratense. caused considerable bulld-up o? Pratylenchus penetrans in flelds already lnfested antf ltself suffered from attack. Howver, if Afrlcan marlgolds, Tagetes sp., wre grown before crops susceptlble to P. penetrans, these nematodes wre suppressed and Tagetes could be used as a green manure.

0800EPPS, J.M. & CHAMBERS, A.Y., 1959. "Mung bean (Phaseolua aureus). a host of the soybean cyst nematode (Heterodera

tlycines).*' Plant Disease Reporter, 43 (9), 81-982.

Two yarietles of Mung bean (Phaseolua aureus), Oklahoma 12 and Klloga, wre very susceptlble to Heterodera glyclnes but a "Jumbo strain" tested appeared to show a high reslstance to white female develop-ment.

0801 GRUNDBACHER, F.J. 6 STANFORD, E.H., 1962. ^,rEffect of temperaturę on reslstance