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of alfalfa to thc sten nematode

(Dltylenchus dlp8acl).^,ł Phytopathology. 52

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The real8tance of seedllng and clonal lants of luceme to infestatlon by Itylenchus dlpsacl yarled in reslstant stratna wlth temperaturę. At 50°F. Łahontan was morę resistance than at 60°F. and 70°F. but selection8 of an introduced yariety from Iran and the varlety Talent dld not vary at these 3 teoperatures.

0802GRUNDBACHER, F.J.,    1962. "Testlng

alfalfa seedllnga for resistance to the sten nematode Dltylenchus dlpsacl (Kuhn) Filipjev.” Proceedlng8 of the Helmlnthol-ogicai Soclety of Washington, 29    (2),

152-158.

Germlnated luceme seedllngs were grown on filter paper rolls wrapped around glass vials ln a breaker of tap-water or dllute Hoagland's solutlon kept in a controlled envlronment. Dltylenchus dlpsacl were extracted from arled Tuceme tops and suspended in 1% sodium carboxymethyl-cellulose, a droplet of whlch was placed between the cotyledons. Inoculated seed-lings were then kept under contlnuous llght for 5 days, preventing the cotyledons froo cios Ing, whlch resulted in a greater concentratlon of D. dlpsacl in the shoot apex. Hlcroscoplcal examlnatłons of stalned seedllngs showed that D. dlpsacl could reproduce ln the hypocotyl, cotyledons and petloles of both susceptible and reslstant plants. In susceptible plants, one month after inoculatlon and grown at 52°F., there was swelling of the meristesatlc tissue at the shoot apex and large numbers of eggs were produced by the nematodes; reslstant seedllngs usually showed llttle swelling and nematode reproductlon dld not usually occur. The prlmary shoot often remalned rudlmentary and a secondary shoot was produced whlch overcame the nematode attack. It 18 concluded that hypersensl-tivlty to D. dlpsacl often inhiblts meristematle growth of reslstant plants.

08030*BANN0N, J.R. & REYNOLDS, H.W., 1962. ^,fReslstance of alfalfa to tvo specles of root-knot nematodes.” Plant Disease Reporter, 46 (8), 558-559.

The reactions of 13 breeding llnes of Afrlcan luceme and a Slrsa selection to Meloldogyne 1avanlca and M. Incognlta var. acrlta were tested. The Afrlcan llnes all had very llght infestations of both root-knot specles, the Slrsa selection was llghtly to moderately lnfested and the check varlety, Łahontan, was moderately to heavily galled. It ls clalmed that when hlghly reslstant yarletles are grown the nematode population of an lnfested field ls reduced so that succeedlng crops in the rotatlon will remaln relatlvely free from root-knot damage.

0804 CHEN, T. & RICH, A.E., 1962. "Patho-geniclty of Pratylenchus penetrans on strawberry and Ladlno whlte clover śeed-llng8.” (Abstract.I Phytopathology, 52 (9), 922-923.

Seedllngs of Ladlno whlte clover and strawberry were grown aseptlcally in tubes on modlfled Hoagland's and Knop's Solutions. Pratylenchus penetrans cultured on

clover callus tissue were added to the tubes contalnlng the seedllngs. Nematodes feedlng on the root halrs and epldermls Just behlnd the root cap resulted ln dlsappearance of root halrs, swelling of root tips, darkenlng of roots and stuntlng of plants. These experlmenta demonatrate that P. penetrans ls pathogenlc to Ladlno whlte~clover and strawberry seedllngs ln the absence of all other organisms.

0805 HEYNS, J., 1962. ”A report on South Afrlcan nematodes of the famllles Longidorldae. Belondlrldae and Alalmldae (Nematoda:    Dorylalmoldea), wlth descrlp-

tlons of three new specles.” Nematologlca, 8 (1), 15-20. [French summary p.20.1 Longldoras elongatus. Xlphlnema amerl-canuroT X. hallel7 brevlcaudatum and boryTalmellus tenuldens are recorded from South Afrlca. The 2 female speclmens of X. amcrlcacum morę closely resemble those from Allgarh7 India, deserlbed by Slddiql, 1959 [see Heim. Abs., 29, No. 322) than American materiał. X. yąnderllndel n.sp., Amphldelus n.sp. and D. projectus monohystera n.sp. are described and illustrated. X. yąnderllndel (females only) was found around the ~roots of maize and cowpeas ln the Orange Free State and also around the roots of cowpeas and peanuts ln the Transyaal. It dlffers from X. hallei ln havIng a flattened lip region] shorter spear, a shorter and almost stralght tali and a longer basal bulb, and froo X. attodororua ln the much shorter spear and spear extenslon, the morę poster lor loca-tlon of the vulva and the longer tali. The vulva of X. yąnderllndel ls a conspicuous transverse sllt    47 to 52%) morę than

half the body wldth. Both uterl have one or morę large pouches. D. projectus was found ln cultlvated soli at tne Tobacco Research Statlon, Ruatenburg, Transyaal. It ls distinguished by the amalgaoated lnner parts of the llps belng set off as a prominent lablal dlsc sllghtly morę than half the wldth of the lip region; lt dlffers from D. strlatus ln the hemlspher-Ical tali ending, shorter pre-rectum and smaller slze. A. roonohystera ls descrlbed from a single female from soli ln a cltrus orchard ln Transyaal. Thls specles belongs ln the group of Aiaphldelus spp. havlng relatlvely short taił8. It~ dlffers froo A. uniformie ln havlng no anterlor uterlńe branch, amphlds located sllghtly morę anterlor ly and by the sub-acute tali termlnus.

0808 ROIYAINEN, 0. 6 TINNILA, A., 1963. ^r,The resistance of certaln Finnish red clover yarletles to the stem nematode Dltylenchus dlpsacl (Kuhn) Flllpjev.” Annales Agrlculturae Fennlae, 2 (1), 1-6.

Stern nematode resistance was lnvestlgated ln a large quantlty of Finnish red clover and coopared wlth the Swedlsh variety Merkur and some other forelgn yarletles. Luceme, alslke clover and whlte clover were also Inoculated but they were very reslstant to the nematode population used. A few Finnish local yarletles, especially Kangasala and Talpalsaarl, showed some degree of resistance and although not as reslstant as Merkur they are considered yaluable for further breeding.