The effects of an experimental programme to support students’ autonomy on the overt behaviours of physical education teachers

Although the benefits of autonomy supportive behaviours are now well established in the literature, very few studies have attempted to train teachers to offer a greater autonomy support to their students. In fact, none of these studies has been carried out in physical education (PE). The purpose of this study is to test the effects of an autonomy-supportive training on overt behaviours of teaching among PE teachers. The experimental group included two PE teachers who were first educated on the benefits of an autonomy supportive style and then followed an individualised guidance programme during the 8 lessons of a teaching cycle. Their behaviours were observed and rated along 3 categories (i.e., autonomy supportive, neutral and controlling) and were subsequently compared to those of three teachers who formed the control condition. The results showed that teachers in the experimental group used more autonomy supportive and neutral behaviours than those in the control group, but no difference emerged in relation to controlling behaviours. We discuss the implications for schools of our findings

Mining the sequence data of Rhizobium Leguminosarum BV Trifolii WSM1325 and WM2304

Most clover rhizobial inoculants form effective nitrogen-fixing symbioses with either annual or perennial species (and very few with both). This constraint provides a considerable barrier to agricultural productivity since background populations of R. trifolii may nodulate with an incompatible host but ineffectively fix nitrogen (Yates et al 2008)

Complete genome sequence of the Medicago microsymbiont Ensifer (Sinorhizobium) medicae strain WSM419

Ensifer (Sinorhizobium) medicae is an effective nitrogen fixing microsymbiont of a diverse range of annual Medicago (medic) species. Strain WSM419 is an aerobic, motile, non-spore forming, Gram-negative rod isolated from a M. murex root nodule collected in Sardinia, Italy in 1981. WSM419 was manufactured commercially in Australia as an inoculant for annual medics during 1985 to 1993 due to its nitrogen fixation, saprophytic competence and acid tolerance properties. Here we describe the basic features of this organism, together with the complete genome sequence, and annotation. This is the first report of a complete genome se-quence for a microsymbiont of the group of annual medic species adapted to acid soils. We reveal that its genome size is 6,817,576 bp encoding 6,518 protein-coding genes and 81 RNA only encoding genes. The genome contains a chromosome of size 3,781,904 bp and 3 plasmids of size 1,570,951 bp, 1,245,408 bp and 219,313 bp. The smallest plasmid is a fea-ture unique to this medic microsymbiont

Highly Specific hosts in the Listia section of the Legume Genus Lotononis are nodulated by Methylobacteria and by novel isolates that are a new genus of root nodule bacteria

Symbiotic specificity and nodule morphology are characteristics that can be used as taxonomic markers in the legume genus Lotononis and that support its division into two separate genera. Lotononis (from the Crotalarieae tribe in the Genistoid clade of the sub-family Fabaceae) is of mainly southern African origin, comprising some 150 species of herbs and small shrubs. Our work has shown that Lotononis is nodulated by phylogenetically diverse root nodule bacteria and that different specificity groups exist within the genus

Root nodule bacteria isolated from South African Lotononis bainesii, L. listii and L. solitudinis are species of Methylobacterium that are unable to utilize methanol

The South African legumes Lotononis bainesii, L. listii and L. solitudinis are specifically nodulated by highly effective, pink-pigmented bacteria that are most closely related to Methylobacterium nodulans on the basis of 16S rRNA gene homology. Methylobacterium spp. are characterized by their ability to utilize methanol and other C1 compounds, but 11 Lotononis isolates neither grew on methanol as a sole carbon source nor were able to metabolize it. No product was obtained for PCR amplification of mxaF, the gene encoding the large subunit of methanol dehydrogenase. Searches for methylotrophy genes in the sequenced genome of Methylobacterium sp. 4-46, isolated from L. bainesii, indicate that the inability to utilize methanol may be due to the absence of the mxa operon. While methylotrophy appears to contribute to the effectiveness of the Crotalaria/M. nodulans symbiosis, our results indicate that the ability to utilize methanol is not a factor in the Lotononis/Methylobacterium symbiosis

Microvirga lupini sp. nov., Microvirga lotononidis sp. nov., and Microvirga zambiensis sp. nov. are Alphaproteobacterial root nodule bacteria that specifically nodulate and fix nitrogen with geographically and taxonomically separate legume hosts

Strains of Gram-negative, rod-shaped, non-spore-forming bacteria were isolated from nitrogen-fixing nodules of the native legumes Listia angolensis (from Zambia) and Lupinus texensis (from Texas, USA). Phylogenetic analysis of the 16S rRNA gene showed that the novel strains belong to the genus Microvirga, with 96.1 % or greater sequence similarity with type strains of this genus. The closest relative of the representative strains Lut6T and WSM3557T was M. flocculans TFBT, with 97.6-98.0 % similarity, while WSM3693T was most closely related to M. aerilata 5420S-16T, with 98.8 % similarity. Analysis of the concatenated sequences of four housekeeping gene loci (dnaK, gyrB, recA, rpoB) and cellular fatty acid profiles confirmed the placement of Lut6T, WSM3557T and WSM3693T within Microvirga. DNA:DNA relatedness values and physiological and biochemical tests allowed genotypic and phenotypic differentiation of Lut6T, WSM3557T and WSM3693T from each other and from other validly published Microvirga species. The nodA sequence of Lut6T was placed in a clade that contained strains of Rhizobium, Mesorhizobium and Sinorhizobium, while the 100 % identical nodA sequences of WSM3557T and WSM3693T clustered with Bradyrhizobium, Burkholderia and Methylobacterium strains. Concatenated sequences for nifD and nifH show that Lut6T, WSM3557T and WSM3693T were most closely related to Rhizobium etli CFN42T nifDH. On the basis of genotypic, phenotypic and DNA relatedness data, three novel species of Microvirga are proposed: Microvirga lupini (Lut6T = LMG26460T, = HAMBI 3236) Microvirga lotononidis (WSM3557T = LMG26455T, = HAMBI 3237) and Microvirga zambiensis (WSM3693T = LMG26454T, = HAMBI 3238)

A re-appraisal of the biology and terminology describing rhizobial strain success in nodule occupancy of legumes in agriculture

Aim: To ensure that the majority of nodules on a legume are occupied by the inoculant strain poses a significant challenge to maximising nitrogen fixation in agricultural settings. The aim of this review is to establish a set of common terms with which to classify and interrogate experiments that investigate nodule occupancy in legumes. Results: At least six different terminologies have been developed to discuss experimental outcomes where legumes have access to more than one rhizobial strain. In this review we nominate a set of preferred terms: promiscuous, exclusive, selective and non-selective nodulation in an attempt to provide conformity to the general scientific pursuit of understanding the circumstances leading to nodule occupancy in legumes when more than one strain has the opportunity to form the nodule. Discussion: To maximise nitrogen fixation from legumes, a primary challenge is to prevent rhizobia resident in the soil from dominating nodule occupation, since whilst they may be numerically dominant, they are often not optimally matched for nitrogen fixation with the introduced legume. It is apparent, however, that at times the legume host is able to preferentially enter into symbiosis with a fully effective strain, even if an ineffective strain is present and numerically dominant. Conclusion: This manuscript reviews the terminology currently applied to nodulation outcomes in introduced legume symbioses where more than one strain type is available to infect the plant. We suggest adoption of a more stringent terminology as the research discipline matures to exploit genome sequence information. We have suggested the term "selective nodulation" to describe certain nodulation outcomes that are not based upon numerical supremacy

Nodule morphology, symbiotic specificity and association with unusual rhizobia are distinguishing features of the genus Listia within the southern African crotalarioid clade Lotononis s.l.

Background and Aims: The legume clade Lotononis sensu lato (s.l.; tribe Crotalarieae) comprises three genera: Listia, Leobordea and Lotononis sensu stricto (s.s.). Listia species are symbiotically specific and form lupinoid nodules with rhizobial species of Methylobacterium and Microvirga. This work investigated whether these symbiotic traits were confined to Listia by determining the ability of rhizobial strains isolated from species of Lotononis s.l. to nodulate Listia, Leobordea and Lotononis s.s. hosts and by examining the morphology and structure of the resulting nodules. Methods: Rhizobia were characterized by sequencing their 16S rRNA and nodA genes. Nodulation and N2 fixation on eight taxonomically diverse Lotononis s.l. species were determined in glasshouse trials. Nodules of all hosts, and the process of infection and nodule initiation in Listia angolensis and Listia bainesii, were examined by light microscopy. Key Results: Rhizobia associated with Lotononis s.l. were phylogenetically diverse. Leobordea and Lotononis s.s. isolates were most closely related to Bradyrhizobium spp., Ensifer meliloti, Mesorhizobium tianshanense and Methylobacterium nodulans. Listia angolensis formed effective nodules only with species of Microvirga. Listia bainesii nodulated only with pigmented Methylobacterium. Five lineages of nodA were found. Listia angolensis and L. bainesii formed lupinoid nodules, whereas nodules of Leobordea and Lotononis s.s. species were indeterminate. All effective nodules contained uniformly infected central tissue. Listia angolensis and L. bainesii nodule initials occurred on the border of the hypocotyl and along the tap root, and nodule primordia developed in the outer cortical layer. Neither root hair curling nor infection threads were seen. Conclusions: Two specificity groups occur within Lotononis s.l.: Listia species are symbiotically specific, while species of Leobordea and Lotononis s.s. are generally promiscuous and interact with rhizobia of diverse chromosomal and symbiotic lineages. The seasonally waterlogged habitat of Listia species may favour the development of symbiotic specificity