Investigations of the host feeding preferences ofSitona weevils found commonly on white clover (Trifolium repens) in the UK

A series of laboratory and field studies were done to evaluate a range of leguminous plant species for their feeding potential by adult weevils of the genusSitona Germar. (Coleoptera: Curculionidae). Three species ofSitona, S. lineatus L.,S. flavescens Marsh. andS. hispidulus F. all of which are found commonly on white clover (Trifolium repens L.) in the UK were offered a range of 11 legume species,T. repens (white clover, cv. Olwen),T. pratense L. (red clover, cv. Marcom),T. fragiferum L. (strawberry clover, cv. Palestine),T. hybridum L. (hybrid clover, cv. Tetra),T. incarnatum L (crimson clover),T. dubium Sibth. (lesser yellow trefoil),Lotus corniculatus L. (birdsfoot-trefoil, cv. Leo),L. uliginosus Schkuhr. (large birdsfoot-trefoil),Melilotus alba Desr. (white melilot),Medicago sativa L. (lucerne, cv. Europe) andM. lupulina L. (black medick) in two laboratory experiments. The weevils were offered a choice of these legumes in one experiment whilst in the other they did not have a choice of food material. These legumes were also sown in the field and a number of measurements of damage, together with counts ofSitona spp., were made. In the laboratoryS. lineatus andS. hispidulus favoured some of the legumes to a greater or lesser extent than white clover.S. flavescens was more restricted in its feeding than the other two weevil species. In the field studyS. lineatus invaded the experimental area quickly and tended to favourMedicago spp. andMelilotus spp. Later in the yearS. flavescens dominated the sitona fauna on the experiment, with the exception of aggregations ofS. lineatus onM. sativa andM. alba. In a separate screen of 5 varieties of white clover (cvs Donna, Menna, Kersey, Olwen and Grasslands Huia), cv. Olwen appeared to be the most susceptible to sitona attack.     

The differential mortality ofTrifolium repens andPhleum pratense seedlings in relation to temperature

Summary 1. The pathogenic potential of test soils towards germinating seeds ofTrifolium repens andPhleum pratense showed marked variation with time, but no apparent relation to seasonal changes or to the condition of the soil.2. The two species differed in their response to pathogenic factors and the ratioT. repens :P. pratense in the seedlings which emerged showed marked variation.3. Both pre- and post-emergence mortality ofT. repens occurred, whileP. pratense responded to low soil temperature mainly by failure to germinate, through death, and more often enforced dormancy of the seed.4. Chilling the seed in wet soil before germination increased mortality considerably.P. pratense stands were reduced at temperatures below 10°C. Losses ofT. repens were small above 5°C, but at 0°C and below losses were heavier than ofP. pratense.5. In sterilised soil, establishment was consistently better than in corresponding unsterilised soils. Fungicide treatment of the seed in unsterilised soil resulted in improvement of stands in most cases, but less than soil sterilisation.6. The improvement in emergence due to soil sterilisation or fungicide treatment was much the same after all pre-chilling treatments.7. The relationship of germination behaviour and liability to pathogenic attack under different temperature conditions is discussed in the light of experience in the field.     

Effects of leguminous ground cover competition on red birch and soil nutrient status in the nursery

Legumes as ground cover are regularly planted to increase nitrogen economy of crops and to improve soil. In the present study various clover species were evaluated as vegetative ground cover in nursery field production of micropropagated red birch (Betula pubescensEhrh. f. rubraUlvinen f. nova) in two 2-year experiments. The clover species and cultivars, Trifolium pratenseL. ‘Bjursele’, T. repens L. ‘Jogeva’, T. repens L. ‘Sonja’, T. hybridum L. ‘Frida’, T. incarnatum L. ‘Opolska’, T. resupinatum L. and T. subterraneum L. were compared to grass sod Festuca rubra L. ‘Ensylva’ and to a coverless ground (control). The last one was kept weed free by hand hoeing. Birch (leaves, stems, branches and roots) and soil nutrient concentrations (N, P, K, Ca, Mg and Fe) were analysed and nutrient ratios in birch determined. The annual clovers, T. incarnatumL., T. resupinatumL. and T. subterraneumL., provided about the same nutrient status in birch as did the control. Perennial clovers and grass were strong competitors with trees. High levels of P and Mg in birch leaves relative to N concentration were typical for poorly growing seedlings. Neither annual nor perennial clovers did generally improve soil nutrient status. This revised version was published online in June 2006 with corrections to the Cover Date.     

In vitro fertilization and seed development inTrifolium

Summary Pistils ofTrifolium repens L. andT. ambiguum Bieb. were cultured on an agar-based modified Murashige-Skoog medium. Pistils with and without accessory floral parts were removed from flowers of selected clones ofT. repens, hand-pollinated under aseptic conditions, and planted on the medium. Pistils cultured without accessory floral parts showed no evidence of fertilization after 2 weeks. However, 52% of thoseT. repens pistils cultured with calyx lobes and pedicels contained ovules with maturing embryos 12 days after in vitro cross-pollination. Pistils fromT. ambiguum intraspecific cross-pollinations could not be cultured successfully under the same conditions; however, addition of various combinations of auxin, cytokinin, and gibberellic acid enhanced embryo growth. Fertilization and partial embryo development occurred in interspecific crosses betweenT. ambiguum andT. repens orT. hybridum only whenT. ambiguum was used as the pistillate parent. These results indicate that embryological development under in vitro conditions closely parallels in situ development although growth regulator requirements may vary among species. This work is Technical Contribution 1785 from the South Carolina Agricultural Experiment Station and was supported by SCAES-USDA Cooperative State Research Agreement No. 616-15-65.     

Nitrogen accumulation in kaolin mining wastes in cornwall

Summary Nitrogen accumulation was studied in mica and sand mining wastes of Cornwall after twelve forage legume varieties were established with the use of lime and fertilizers containing phosphorus and potassium. In the finetextured mica waste legume productivity and nitrogen accumulation were similar to those for upland pastures in Cornwall; but legume growth was limited by summer drought on the coarse-textured sand waste. Native perennial legumes well adapted to the British climate were the most productive and showed the highest potential for nitrogen fixation. More than 500 kg N/ha accumulated during the 2-year period whenTrifolium pratense andLotus corniculatus were established on mica waste, and more than 250 kg N/ha was accumulated by these legumes on sand waste.Trifolium pratense andLotus corniculatus were persistent on both the mica and sand waste, andMedicago lupulina showed an unusually high tolerance for competition from invading and sown grass on the sand waste.Trifolium repens andT. hybridum are recommended for waste sites where grazing is a part of management.Nitrogen accumulation on mica waste was consistent with N fixation rates expected from climatic conditions. Nitrogen fixation by free-living bacteria is limited by the low organic matter content of the wastes. The nitrogen fixation potential by legumes on sand wastes has been underestimated because leaching losses were not adequately evaluated. Since nitrogen accumulation rates by earlyTrifolium pratense andT. repens were 70 percent higher than the maximum rate estimated for natural legumesi.e. (Ulex europaeus) on sand waste, the use of forage legumes should reduce reclamation time considerably. re]19760512Department of Botany Liverpool University     

Genetic similarity among Trifolium species based on isozyme banding pattern

The study deals with similarity among 25 species of the genus Trifolium represented by 134 accessions. Clustering of the species based on isozyme banding pattern of five enzymes revealed that T. repens was distinctly different from other species. T. repens and T. retusum formed independent clusters. The group of species comprising of T. pratense, T. cherleri, T. spumosum, T. subterraneum, T. resupinatum, T. alexandrinum, T. echinatum, T. constantinopolitanum and T. tembense exhibited considerable similarity to the second cluster. This group joined another group of five species, i.e. T. nigrescens, T. glomeratum, T. apertum, T. alpestre and T. hybridum with nearly 50% similarity. T. purpureum, T. hirtum, T. campestre, T. incarnatum, and T. argutum grouped separately. There was no marked difference for banding pattern among T. alexandrinum genotypes. T. alexandrinum showed close affinity with T. subterraneum and T. resupinatum. T. lappaceum, T. diffusum, T. campestre, T. incarnatum and T. argutum showed only 44.8% similarity with other Trifolium species. Grouping together of accessions belonging to individual species indicated that incompatibility among species under study had restricted interspecific hybridization. Species belonging to subgenus Lotoidea clustered with species of subgenus Trifolium. Chonosemium species T. campestre formed one cluster with two Trifolium species T. hirtum and T. incarnatum. T. nigrescens was placed quite apart from the T. repens.     

Retention of phytoalexin regulation in legume callus cultures

Legume callus cultures were examined to assess whether regulation of phytoalexin biosynthetic pathways is retained in cultured tissues. Callus tissue cultures ofCanavalia ensiformis (jackbean),Medicago sativa (alfalfa), and nine species ofTrifolium (clover) were established (six clover species for the first time) and maintained on modified Gamborg's B5 medium. Phytoalexins educed in cultures incubated for 48 h with an abiotic elicitor (3.15 mM HgCl₂) were detected by their antifungal activity and were purified by column chromatography and high-performance liquid chromatography. Following crystallization, phytoalexins were identified by ultraviolet and proton nuclear magnetic resonance spectroscopy. None of the treated cultures yielded the same complement of phytoalexins reported for fungal-inoculated leaves of the corresponding plants. Callus from all species exceptT. pratense yielded medicarpin, the only phytoalexin reported in treated leaves of all the corresponding plants. A second phytoalexin, maackiain, was found in treatedT. pratense andT. medium calli; maackiain has been reported in fungal-inoculated leaves of those plant species as well asT. hybridum. The phytoalexins sativan and vestitol were not found in treated callus tissues even though they were reported to be present in fungal-inoculated leaves of the same species. These results suggest that (a) the pathway for medicarpin biosynthesis is of central importance for this group of legumes, (b) some phytoalexin anabolic pathways contain metabolic blocks in cells of cultured tissue, and (c) the mechanism for regulating phytoalexin accumulation in tissues is not lost in culture. Contribution no 8113 of the US Regional Pasture Research Laboratory, USDA-ARS, University Park, PA, USA     

Pollination in vitro: effects on the growth of pollen tubes,seed set and gametophytic self-incompatibility in Trifolium pratense L. and T. repens L.

Summary Growth of pollen tubes and seed set were compared after hand pollination in situ and in vitro in two self-incompatible species, Trifolium pratense and Trifolium repens. Adhesion of pollen grains to the stigma was greater in vitro for both species. After cross-pollination, in vitro culture gave a significant increase in the cumulative growth of pollen tubes in pistils of T. pratense compared to in situ conditions. After selfing in T. repens, pollen tube growth was significantly increased by in vitro culture of florets. Seed set after crossing in situ and in vitro was similar for both species. Seed set after selfing in vitro was not increased in T. pratense. Several genotypes of T. repens were classified as very good, good and poor selfers based on their capacity for seed set following selfing in situ. In vitro pollination increased self seed formation by 1.7-, 18.0- and 31.0-fold for each class, respectively. Ovules located nearest to the style were fertilized more often after selfing than after crossing.     

Isozyme Variation in Wild and Cultivated Species of the Genus Trifolium L. (Leguminosae)

Isozyme patterns for PGI (phosphoglucoisomerase), MDH (malatedehydrogenase), EST (esterase) and SOD (superoxide dismutase)were evaluated in 36 accessions of eight Trifolium species,namely T. incarnatum, T. polymorphum, T. pratense, T. repens,T. resupinatum, T. riograndense, T. subterraneum and T. vesiculosum.Similarity between species and accessions was estimated by Jaccard’ssimilarity index based on presence or absence of bands. TheUPGMA method was utilized for the groupings and dendrogram constructionwith the aid of the NTSYS-PC program. Interspecific similaritywas low (J 0.351). The dendrogram presented eight groups, eachone corresponding to a taxonomic species. Most of the accessionsof the same species grouped together at J > 0.50, exceptT. riograndense, T. repens and T. pratense. These three speciesshowed the lowest similarity between their accessions, reflectinghigher intraspecific variation. Some accession-specific bandswere identified. The species groupings are consistent with traditionaltaxonomic species delimitation. Therefore isozyme patterns,especially when several systems are employed, are useful andreliable biochemical markers for the taxonomic delimitationand characterization of Trifolium germplasm. Copyright 2000Annals of Botany Company Genetic diversity, germplasm characterization, isoenzymatic variability, biochemical markers, isozymes,Trifolium     

Physiological Studies on Nodule Formation. The Characteristics and Inheritance of Abnormal Nodulation of Trifolium pratense by Rhizobium leguminosarum

Five to 7 per cent of plants of Trifolium repens L. and T.pratenseL. and 100 per cent of plants of T. subterraneum L. were nodulatedby Rhizobium leguminosarum but none of T. hybridum L., T. glomeratumL. or T parvifirum Ehrh. The frequency of nodulation of T. pratenseby R. leguminosarum was much increased by breeding from susceptibleplants. Such plants were not nodulated by bacteria isolatedfrom any other cross-inoculation group, but remained fully susceptibleto R. trifolii. The nodules formed by R. leguminosarum are generallyassociated with lateral roots and are ineffective.     

The comparative phosphorus requirements of some temperate perennial legumes

The phosphorus (P) responses of seven temperate perennial pasture legumes and two species of lupins were compared in a field trial over a range of nine P rates, from 0 to 800 kg ha^-1. The two lupins produced more than 5 t ha^-1 of dry matter in the absence of added P and showed no response to the fertiliser. In contrast, the pasture legumes initially failed to grow without added P and responded to applications of between 200 and 800 kg ha^-1. At the higher rates of P, dry matter production of the pasture legumes was equivalent to that of the lupins.In the first 2 years of the trial; the most productive pasture legume species at the higher rates of added P were also the most productive at the lower rates. Phosphorus requirements for 90% of maximum yield varied greatly between species, but were closely related to maximum yield. Thus species with low P requirements for maximum yield were not necessarily P-efficient species. In the third and subsequent years of the trial Lotus corniculatus performed better than the other pasture legumes at the lower rates of added P. In contrast to other studies Lotus pedunculatus showed no ability to outyield Trifolium repens at low rates of P. Critical P concentrations of the pasture species for the late spring-early summer period declined in the order Trifolium repens (0.34%) > Lotus pedunculatus (0.30%) > Triofolium pratense (0.28%) > Trifolium hybridum (0.27%) > Trifolium ambiguum (0.26%) > Lotus corniculatus (0.23%).Mineralisable nitrogen (N) levels were determined in soils under three species in the 7th year of the trial. At the lowest rates of added P, mineralisable N levels were much higher under Lupinus polyphyllus than under Trifolium repens or Lotus corniculatus. With increasing P rate, levels under the latter species increased, and at 100 kg P ha^-1 were equivalent to those under the lupin with no added P.     

The effects of lime-pelleting and lime-superphosphate fertilizer on the growth of three annual legumes in an acid sandy soil

Summary Three pioneer pasture legume species,Trifolium subterraneum, Trifolium glomeratum andOrnithopus compressus, were grown in a sandy soil of pH 5.0. The growth and nodulation of each species was examined in the presence and absence of lime pelleting and with superphosphate and lime-superphosphate fertilizer. In each species tested, plant yield, nodule number and nitrogen recovery as maximal where lime pelleting and lime-super were applied together. Plant calcium indicated that the response to lime was due to changes in soil pH rather than to a calcium response. T. glomeratum was the species most responsive to lime application but its growth was at best only half that ofT. subterraneum andO. compressus, which produced equally under both favourable (pH 5.9) and unfavourable (pH 4.4) conditions created by fertilizer applications.     

The latent trichophytosis of human clothing,II. Some data relating to Trichophyton pratense

Summary The author refers to the results of his investigations carried out with theT. pratense in 1940. He could continue these experiments only in the year 1965. This time he came to the conclusion that three fungi species:T. terrestre Durie &Frey,T. pratense andT. gypseum var.asteroides belong together. He could observe that the cultures of these fungi develop well on some kinds of textile materials. Relying upon these findings he applied the TO-KA-VA method in an inverted way to demonstrate the fungi which had settled on the textiles with the dust of soil. By means of this method he observed thatT. pratense had indeed occurred on some cloths. By further investigation he proved the identity ofT. terrestre Durie &Frey withT. pratense andT. gypseum var.asteroides and demonstrated, that this latter fungus might be the degenerative derivate of the former ones. Finally, he gave as his opinion that the settlement of theT. gypseum var.asteroides is also likely to occur on human clothing; however, far more rarely than that of other kinds of fungi.     

Cytogeography of<Emphasis Type="Italic"> Ixeris nakazonei</Emphasis> (Asteraceae,Lactuceae) in the Ryukyu Archipelago of Japan and Taiwan

The cytogeographical structures of Ixeris nakazonei, a putative hybrid between I. debilis (6x) and I. repens (2x), were investigated in the Ryukyu Archipelago and Taiwan. In the Ryukyus, I. debilis occurs on Miyakojima Island of the southern Ryukyus and northward, while I. repens occurs on all islands except for Iriomotejima and Yonagunijima Islands. I. nakazonei, comprises six polyploid cytotypes, 3x, 4x, 5x, 6x, 7x and 8x, based on x=8. Four cytotypes from 3x to 6x occur in the central Ryukyus, while four cytotypes from 5x to 8x occur in the southern Ryukyus. The higher polyploids of I. nakazonei tend to be distributed in the more southerly area. Tetraploids of I. nakazonei always co-occur with I. debilis and I. repens, supporting the hybrid origin of this cytotype. Considering the chromosome number, octoploids, which predominate in the southern Ryukyus and Taiwan, may have derived directly from hybridization between I. debilis and I. repens. Odd-numbered polyploids of I. nakazonei, 3x, 5x and 7x, are relatively rare. Their chromosome numbers indicate that triploids and heptaploids are hybrids between the tetraploid of I. nakazonei and I. repens, and between the octoploid of I. nakazonei and I. debilis, respectively. Pentaploids of I. nakazonei in the central and southern Ryukyus are, respectively, hybrids between the tetraploid of I. nakazonei and I. debilis and between the octoploid of I. nakazonei and I. repens, indicating that pentaploids of I. nakazonei have at least two independent origins.     

Phylogeny of the GenusTrichodermaBased on Sequence Analysis of the Internal Transcribed Spacer Region 1 of the rDNA Cluster

Sequences of the internal transcribed spacer region 1 (ITS1) of the ribosomal DNA were used to determine the phylogenetic relationships of species ofTrichodermasect.Pachybasium.To this end, 85 strains—including all the availableex-type strains—were analyzed. Parsimony analysis demonstrated that the section is nonmonophyletic, distributing the 85 strains among three main groups that were supported by bootstrap values. Group A comprises two clades (A1 and A2), with A1 includingT. polysporum, T. piluliferum,andT. minutisporum,while A2 includedT. hamatum, T. pubescens,andT. strigosumin addition to species previously included in sect.Trichoderma(i.e.,T. viride, T. atroviride,andT. koningii). Theex-type strain ofT. fasciculatumformed a separate branch basal to clade A. Clade B contained the sect.PachybasiummembersT. harzianum, T. fertile, T. croceum, T. longipile, T. strictipile, T. tomentosum, T. oblongisporum, T. flavofuscum, T. spirale,and the anamorphs ofHypocrea semiorbisandH. cf. gelatinosa.Sequence differences among clades A1, A2, and B were in the same order of magnitude as between each of them andT. longibrachiatum,which was used as an outgroup in these analyses. Sequence differences within clades A1, A2, and B were considerably smaller: in some cases (i.e.,T. virensandT. flavofuscum; T. strictipileandH. cf. gelatinosa), the ITS1-sequences were identical, suggesting conspecifity. In other cases (e.g.,T. crassumandT. longipile; T. harzianum, T. inhamatum, T. croceum, T. fertile,andH. semiorbis; T. hamatumandT. pubescens;andT. viride, T. atroviride,andT. koningii) differences were in the range of 1–3 nt only, suggesting a very close phylogenetic relationship. The sequence of a previously described aggressive mushroom competitor group ofT. harzianumstrains (Th2) was strikingly different from that of theex-type strain ofT. harzianumand closely related species and is likely to be a separate species.     

Comparison of nodulating and non-nodulating strains ofRhizobium trifolii

Summary A non-nodulating mutant ofRhizobium trifolii and its nodulating parent were examined for possible dissimilarities in their extracellular polysaccharides, antigen composition and ability to grow on the roots ofTrifolium pratense. A major distinction between the two organisms was observed to be the inability of the non-nodulating strain to grow in the root-tip region ofT. pratense. A small quantitative difference in antigen composition but no significant qualitative or quantitative differences in the extracellular polysaccharides of the two bacteria were noted. The non-nodulating rhizobium could not be induced to nodulate seedlings ofT. pratense either in the presence of nodulating rhizobia or after ultraviolet treatment of the bacteria.     

Population studies in Goodyera (Orchidaceae) with emphasis on the hybrid origin of G. Tesselata

Morphological, cytological, and paper Chromatographic studies of populations from northern Michigan and examination of herbarium specimens from throughout North America were used to clarify the relationships ofGoodyera oblongifolia, G. repens var.ophioides, andG. tesselata. A canonical analysis of morphological data from mixed populations of these three species depictsG. tesselata as intermediate betweenG. oblongifolia andG. repens var.ophioides. The latter two species are diploid (2n = 30) andG. tesselata is tetraploid (2n = 60). Triploids (2n = ca. 45) were found in two mixed-species populations in northern Michigan.Goodyera tesselata produces three phenolic compounds present inG. oblongifolia and five different compounds present inG. repens var.ophioides. The range ofG. tesselata is confined to glaciated territory (except for two stations) in northeastern North America where the postglacially produced ranges ofG. oblongifolia andG. repens var.ophioides overlap. However,G. tesselata is quite abundant in areas outside the region of sympatry of the other two species. Based on this evidence, it is postulated thatG. tesselata is an allotetraploid species which resulted from hybridization betweenG. oblongifolia andG. repens var.ophioides during early post-Pleistocene. The slightly earlier blooming season ofG. tesselata may have been selected for to provide a measure of reproductive isolation between the tetraploid and its parents and to adapt the new species to the rather short growing season of northeastern North America.     

Antioxidant response to drought in red and white clover

Antioxidant response to drought in red (Trifolium pratense L., cv. ??Start??) and white clover (Trifolium repens L, cv. ??Haifa?? and cv. ??Debut??) grown as soil cultures was evaluated in water-deprived and recovered plants. Drought provoked oxidative stress in leaves confirmed by the considerable changes in electrolyte leakage, malondialdehyde, hydrogen peroxides and proline contents. Immunoblot of ??-1-pyrroline-5-carboxylate synthetase (P5CS), which catalyzes the first two steps in proline biosynthesis, revealed strong induction of the enzyme in red clover plants submitted to drought. Water-deprived white clover plants exhibited distinct P5CS profiles. This was related to different drought tolerance of the studied T. repens cultivars. Isoenzyme analyses of superoxide dismutase (SOD), peroxidase (POX) and catalase (CAT) demonstrated certain differences in antioxidant defence among the tested varieties. It was confirmed that MnSOD (in both T. repens and T pratense) and FeSOD (in T. repens) isoforms were the most affected by drought. The red clover cultivar ??Start?? exhibited the lowest FeSOD and POX activities which could contribute to its poor performance under water deprivation.     

Phytosociological and environmental gradients in a sector of the Western Desert of Egypt

Summary The climatic and physiographic features of the Western Desert of Egypt vary gradually from the Mediterranean coast inland. The present study provides an analysis of the gradients exhibited by these environmental variations and their relationships with vegetational gradients and the phytosociological behaviour of species in a sector along the Cairo-Alexandria desert road. The multivariate analyses of the vegetation lead to the recognition of six interrelated vegetational groupings which were distributed along a climatic gradient of increasing aridity, and an edaphic gradient of increasing sandiness and decreasing salinity and level of total phosphorus. These groupings were distinguished into three sets: a set ofConvolvulus-Helianthemum-Artemisia, andHelianthemum-Echiochilon, a set ofAnabasis, andSalsola-Anabasis, and a set ofAsphodelus-Noaea andThymelaea-Anabasis-Noaea groupings. The first set occupies the more arid end of the climatic gradient and the end of the coarse texture, low salinity and low levels of total phosphorus of the edaphic gradient. The second set occupies the opposite end of the edaphic gradient and the middle position of the climatic gradient and the middle position of the climatic gradient, and the third, the middle position of the edaphic gradient and the less arid end of the climatic gradient. Taxonomic nomenclature is according to T?ckholm (1974). The multivariate analyses were carried out using a Burroughs B6700 at the Computer Center of Utah State University, and supported by the U.S. Desert Biome. The authors are indebted to W. Valentine, H. C. Romesburg and K. Marshall for their assistance with data processing.     

Transformation of forage legumes using Agrobacterium tumefaciens

Summary Galls were induced in six species of forage legumes following inoculation with wild-type strains of A. tumefaciens. The plant species was more influential than the bacterial strain in determining the type of tumour produced. Inoculation of Medicago sativa resulted in small, disorganised tumours. The three Trifolium species, T. repens, T. hybridum and T. pratense, formed galls which tended to produce roots and both Onobrychis viciifolia and Lotus corniculatus produced teratomatous galls. The shoots elongated in the latter species only. In L. corniculatus, tissues that were infected by five bacterial strains were capable of shoot regeneration when cultured on a hormone-free medium. The transformed nature of these shoots was confirmed by their failure to root, the production of callus from leaves cultured on hormone-free medium and the presence of opines.