Towards a characterisation of the wild legume bitter vetch (Lathyrus linifolius L. (Reichard) Bässler) : heteromorphic seed germination, root nodule structure and N-fixing rhizobial symbionts

Jacovo, E. Dello and Valentine, T. A. and Maluk, M. and Toorop, P. and Lopez del Egido, L. and Frachon, N. and Kenicer, G. and Park, L. and Goff, M. and Ferro, V. A. and Bonomi, C. and James, E. K. and Iannetta, P. P. M. (2018) Towards a characterisation of the wild legume bitter vetch (Lathyrus linifolius L. (Reichard) Bässler) : heteromorphic seed germination, root nodule structure and N-fixing rhizobial symbionts. Plant Biology. ISSN 1438-8677 (https://doi.org/10.1111/plb.12902)

[thumbnail of Dello-Jacovo-etal-PB-2018-Towards-a-characterisation-of-the-wild-legume-bitter-vetch]
Preview
Text. Filename: Dello_Jacovo_etal_PB_2018_Towards_a_characterisation_of_the_wild_legume_bitter_vetch.pdf
Accepted Author Manuscript

Download (2MB)| Preview

Abstract

Lathyrus linifolius L. (Reichard) Bässler (bitter vetch) is a fabaceous nitrogen (N) fixing species. A coloniser of low nutrient (N) soils it supports biodiversity such as key moth and butterfly species and its roots are known for their organoleptic and claimed therapeutic properties. Thus, the species has high potential for restoration, conservation, novel cropping and as model species. The latter owing to its genetic synteny with important pulse crops. However, regeneration and functional attributes of L. linifolius remain to be characterised. Seeds of L. linifolius were characterised using physical, colourimetric and chemical data. Ultrastructural and functional characterisation of the N fixing root nodules included immunolabelling with nifH-protein antibodies (recognising the N fixing enzyme, nitrogenase). Endosymbiotic bacteria were isolated from the root nodules and characterised phylogenetically using 16S rRNA, nodA and nodD gene sequeneces. L. linifolius yielded hetermorphic seeds of distinct colour classes: green and brown. Seed morphotypes had similar carbon:N ratios and were equally germinable (ca. 90%) after scarification at differing optimal temperatures (16 and 20°C, respectively). Brown seeds were larger and comprised a larger proportion of the seed batch (69%). L. linifolius root nodules appeared indeterminate in structure, effective (capable of fixing atmospheric N) and accommodated strains with high similarity to Rhizobium leguminosarum biovar viciae. The findings and rhizobial isolates have potential application for ecological restoration and horticulture using native seeds. Also, the data and rhizobial resources have potential application in comparative and functional studies with related and socio-economically important crops such as Pisum, Lens and Vicia.