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0 03 0 BritaIN, Plant Breeoing iNsriTUTE Annual report 1977. Cambridge, UK. (1978) 168 pp. [En, Plant nematology pp. 28-29, 74, 77, 82, 85-86)

Brief reports are given of field tests of potato clones for resistance to Globodcra roslochiensis, and of commcrciai diploid varieties of red clover for resistance to Ditylcnchus dipsaci. Two techniąues are describcd for assessing resistance of luceme seedlings to D. dipsaci. Symptoms appeared after 24 hours. Of 9 varieties tested nonę was as resistant as cv. Lahontan but there were real and repcatable difTcrcnces between varieties and it i$ concluded that resistant varieties could be bred. Breeding of potatoes has becn continued with the object of combining resistance to pathotype Roi of G. rostochiensis with resistance to pathotypes Pal and Pa3 of G. pallida.

003 1 Vovlas, N.; Inserra, R. N. BiologicaJ rcaatioiiship of Rotylencbulus borealis on seteral plant casttiT&rs. Journal of Nematology (1982) 14 (3) 373-377 [En, LZZ Tef.) Inst. di Neraatoiogia agraria dcl Consiglio Nazionale de=Be Ricerche, 70126 Bari, Italy.

The embryogenic development of R. borealis, at 24 to ZfićTC, was compieted on maize in 12 to 15 days, and the life-cjjcde of the nematode from egg to egg required 35 to 40 days ajc HO to 25'C. Juveniles remained in the soil as preLofective staągcs for 17 to 19 days before becoming adults. Oniy imnmature vermifonn and swollen egg-Iaying females were fbmmd attached to maize roots. Eggs were laid in a gelatinous ansam* on the root surface; che number of eggs/egg mass was 4ST- ^ 28 on maize roots. Bean, green pea, potato, sorgbum, annr sweet potato were also found to be hosts of R. borealis. Tnce nematode establishcd a permanent feeding site on maize rooot in an endodennal celi that became hypertrophied. Pceaicyclic cells close to the feeding site showed granular cyimjplasm and nuclei with hypertrophied nucleoli. A celi wali ingrowth was also noted around the area of stylet penetration into the endodermal celJ.

*00 32 SHEAFFER, C. C.; RabaS, D. L.; FrOSHEISER, F. I.; Nelson, D. L. Nematicides and fungicides iroprore legume establishment. Agronomy Journal (1982) 74 (3) 536-538 (En, 13 ref.) Dep. of Agronomy & PI. Genetics, Univ. of Minnesota, St. Paul, MN 55108, USA.

In a field ezpeoment in Minnesota, USA, application of pbenamiphos (5.6 kg a.i./ha), aldoaycarb (8.9 kg a.i./ha) or carbofuran (2.2 kg a.i./ha), prior to planting with luceme or birdsfoot trefoil, inereased legume yields compared to Controls in the planting and following year. Carbofuran or pbenamiphos were morę efTective than aldosycarb. Soil nematode populations were unafTected. In a 2nd field experiment, carbofuran (2.2 kg a.i./ha) alone or in combinations with metalazyl (2.2 kg a.i./ha) or benornyl (16 kg a.i./ha) gave significantly greater luceme yields than Controls or fungicides alone. Soil nematode populations were unafTected although carbofuran or carbofuran-fungicide nuAtures significantly reduced Pratylenchus pencirans numbers in luceme roots. It is suggesićd that a nemutode-fungus disease comples may be responsible for poor scedling establishment and yields of luceme.

003 3 SHARMA R. D.; SwarUP, O.    Hi the rt o unrecorded

plant par&sitic nematodes of Andropogoo gayanus Kunth. taj. tnsquamulBtus Stapf. frora Cerrado rr^oo of DraziL la

Trabalhos apresemados i VI ceumio Braju lara dc Hematologia. 8-12 fevcreiro de 1982, Fortilcra. Puhlica^ao No. 6. (Edited by: Lordello. L.G.E.) Pi racica ba. SP. Oraz ił; Sociedade Brasileira de Nematologia (1982) 99-102 (En. 5 ref.) EMBRAPA. CPAC. Planaitioa-DP. Bnml.

A survey of 10 soil and root samplca of A. gayanu.t var. bisĄuamulalus cv. ‘PlanaJtina' from PLanaltina. Brazil reveaied the following plant parasitic nematode*: Pratylenchus bracbyurus, Helicotylcnchus digonicus md Macroposthonia omata. The dominant species. H. digomcui.

15 reported for the first time from Brazil. Oihcr gen era and species present were: Tylencbus, Apbelenchoides. Ditylcnchus and Apbelencbus avenae. This is the first report of ibcse 94

nematodes associated with andro pogoń grass from the Cerrado regjpns of Brazil.

003 4 SKESTEPEROV. A. A. (Uynumics ol' paraSitic nematodes on Trifolium pratense.) Byullcten' Ysesoyuznogo Instituta Gel'mintologii im. K.I. Skryabina (1981) No.31, 98-104 (Ru. en. 8 ref.)

The seasonal variation in the numbers of che spccific plant pathogenic nematodes of T. pratense — Pratylenchus pratensis, Tylenchorhyncbus dubius and Paratylcnchus projectus — in the roots. rhizosphere and soil were studied [in the Europcan SSR). Vegciative sta ges (flowering and preparation for winter), humidity < 16%. large numbers of predatory nematodes. antagonism, numbers of bacteria and fungi. ploughing and crop rotation had a limiting efTect on P. projectus populations. Often, 4th stage larvae were the dominant stage in the soil. Migration from roots to rhizosphere to soil, and vice-vcrsa and into decp soil layers was often observed. AB these factors and, especiaBy antagonism with P. projectus and with spec i es of Tylencbus, Aglencbus and FUenchus also influeneed the population dynamics of T. dubius. Peak numbers of T. dubius coincided with Iow numbers of P. projectus. Pratylenchus pratensis had Little influence on population dynamics and was found mainiy in smali roots at 25 to 60 cm.

0 0 3 5 Putsa, N. M. [Chan ges in numbers of Ditylcnchus dipsaci and its distribution on Trifolium pratense and in soil.) Byullcten’ Ysesoyuznogo Instituta Gcl’mintologii im. K.I. Skryabin (1981) No.31, 40-44 (Ru, en, 9 ref.)

The distribution of D. dipsaci on Trifolium pratense seedlings was studied in ezperiraentaBy infected plants. At the 2-!eaf stage, most of the nematodes were in the epicotyl and the upper part of the hypocotyl; only 2.3% were in the cotyledon and only in 8.6% of the plants. Other plant organs were graduaUy penetrated but no nematodes were found in the roots of cither susceptible or resistant var. at 5 weeks. At aB stages most of the nematodes and eggs were in the bud and in the epi- and hypocotyl. The nematodes multiplied and acćumuiated in the leaf stalks and veins; few were found in the mesophyB. At 5 weeks, there were 118.0 nematodes and 81.2 eggs/piant of the susceptible var. and 69.8 and 59.4 respectiyely on the resistant var. The distribution of D. dipsaci on adult plants was studied over 3 years in the field (in USSR). Most nematodes were found in the stems at aB stages of growth, foBowed by leaves, root neck and roots (very few nematodes were in the roots). At the end of vegetative growth most nematodes found in the soil were in the 0-10 cm layer; there were nonę below 30 cm.

0036 Skipp, R. A.; CHRisrENSEN, M. J. Inrasioo of wbite cloter roots by fungi and other soil micro-organisms. IV. Surrey of root-inrading fungi and nematodes In sonie New ZeaJand pas tur es. New Zealand Journal of AgricuJturaJ Rescorcb (1983) 26 (l) 151-155 [En, 18 ref.) Pi. Dis. Div., DS/K, Private Bag, Paimerston Nortb, New Zealand.

A survey of nematode invaders of white clover roots trom pastures throughout New Zealand showed Heterodera trifolii, Mcloidogync spp. and Pratylenchus spp. to be present in samples from 75%, 58% and 48% of sites respectively.

0 0 3 7 Singh, D. B.; Reddy, P. P. Chemical control of Meloidogyne incognita infecting cowpea. Indian JoumaJ of Nematology (1982) 12 (1) 196-197 [En, 2 ref.) Indian InsL.of Horticultural Res., Bangalore 560080, India.

In a field experiment in Bangalore, India, aldicart). carbofuran, ethoprop or phenamipbos at 0.5, 1.0 or 1.5 kg ą-i./ha was applied one day before sowing cowpea seeds. AB nematicides significantly reduced the root-knot index and inereased yields compared to Controls; phenamipbos and aldicarb being the most effective.

0 03 8 Germani, G.; Cuany, A.; Merny, G. [Factorial onaiysis of the effect ot 2 nematodes on the growth of Aracbis and on the symbiotic fiaation of nitrogeo.) L’analyse