The Gene Pools of the Grasspea (Lathyrus sativus L.)

Interspecific hybridization between the grasspea, Lathyrus sativus, and 15 wild species in Section Lathyrus is reported. Only two species, L. amphicarpos and L. cicera produced viable F¹ hybrids with low fertility when crossed with L. sativus as male parent. Crosses with six other species produced pods following pollination when L. sativus was the male, but seedlings were inviable, seeds did not germinate or pods were empty or had totally shrivelled seeds. When L. sativus was the female parent, only one cross with L. gorgoni produced an F¹, but the seedling was inviable. The germplasm resources of the grasspea are identified, with L. amphicarpos and L. cicera placed in the secondary gene pool and the other species in the tertiary gene pool. The definition of these germplasm resources is discussed in terms of grasspea improvement through plant breeding.     

Diversity of seed albumins in the grasspea (Lathyrus sativus L.): an electrophoretic study

Electrophoretic analysis of seed albumins covered 105 Lathyrus sativus accessions originating from different geographical regions. Four major albumin bands were responsible for the detected variation. Due to differences in the number and combination of these bands, eleven electrophoretic seed albumin patterns were distinguished; four of them were rare phenotypes found in less than 1% of the 817 examined individuals. Electrophoretic data were subjected to statistical analysis using hierarchical UPGMA grouping and biplot techniques. Generally, no correlation was found between occurrence of either the seed albumin patterns or the major albumin bands and geographical origin of the forms under study. On the other hand, data concerning frequency distribution of the major albumin bands tended to separate two groups of accessions, white-seeded with large seeds and coloured-seeded with relatively small seeds; coloured-seeded accessions with rather large seeds mixed with the above groups.     

Diversity of seed globulins in Lathyrus sativus L. and some related species

Sodium dodecyl sulphate-polyacrylamide gel electrophoresis of reduced seed globulins covered 141 accessions of Lathyrus sativus and the following related species: L. amphicarpos, L. blepharicarpus, L. cicera, L. gorgoni, L. marmoratus, L. pseudocicera and L. stenophyllus. In the total examined material 71 globulin polypeptide bands were distinguished. The number of polypeptide bands detected in particular species varied from 14 in L. amphicarpos to 29 in L. sativus; all the species under study showed intraspecific variation due to individual variation and/or differences among accessions. Electrophoretic data were subjected to statistical analysis using hierarchical UPGMA grouping. Frequency distribution of polypeptide bands in L. sativus showed some correlations with geographical origin and certain seed characteristics (seed coat colour, seed weight) of the studied accessions. As regards interspecific relationships, the studied species showed to be distantly related taxa except for the rather closely allied L. cicera and L. marmoratus. The obtained results are compared with the electrophoretic seed albumin data reported earlier for the same taxa.     

Phenotypic polymorphism of six enzymes in the grasspea (Lathyrus sativus L.)

Summary The phenotype variation in six enzymes, 6-phosphogluconate dehydrogenase (6-PGD), malate dehydrogenase (MDH), peroxidase (PRX), isocitrate dehydrogenase (IDH), galactose dehydrogenase (GD) and glutamate oxaloacetate transaminase (GOT), was investigated using horizontal starch gel electrophoresis in 52 accessions of the grasspea, Lathyrus sativus. Phenotypic polymorphism was observed for all six enzymes. High phenotypic polymorphism (Pj) was observed for PRX and 6-PGD, while there was little polymorphism for GOT, with only two accessions showing variation. There was no correlation between phenotypic polymorphism and region of origin, or groupings of accessions made on the basis of flower colour. Tentative genetic interpretations of banding patterns are given for five of the enzyme systems. The level of apparent heterozygosity was higher than expected in this predominantly autogamous species. The level of variation in the grasspea is discussed in terms of its potential for exploitation through plant breeding.