RHIZOMATOUS LOTUS-CORNICULATUS L - III - INTROGRESSION OF RHIZOMES INTO AUTOGAMOUS GERMPLASM

Introduction of genes for rhizomes from wild Lotus corniculatus L. ger mplasm into domesticated germplasm may be an important step towards im proving persistence of cultivated L. corniculatus, normally a cross-po llinated herbage crop. This study was initiated to determine if rhizom es could be transferred to a L. corniculatus germplasm that sexually r eproduces via autogamy. Autogamy is an unusual reproductive expression in this typically self-incompatible species. Compatibility was high b etween the autogamous germplasm AG-S4 and five wild Moroccan accession s with rhizomes. Higher crossing success was obtained when AG-S4 was u sed as a maternal parent Most seeds produced were normal in appearance and size and had high germination. The resulting F-1 progeny were mor phologically intermediate between the parents for size and shape of le af and floral characters, but appeared more similar to their Moroccan parents. Differences between reciprocal crosses were not evident. Hybr idity of progeny was confirmed by random amplified polymorphic DNA (RA PD) analysis using eight primers. Fertility of F-1 progeny was low rel ative to their parents. Meiosis of parental genotypes was characterize d by a high frequency of bivalents, but the meiotic behavior of their F-1 hybrids was more irregular. The frequency of univalents varied fro m 0 to 8 with an average 2.4 per cell, indicating homology of chromoso mes between AG-S4 and Moroccan accessions was not complete. Rhizomes w ere successfully expressed in F-1 hybrids and a small, number were fou nd to also be autogamous. The autogamous hybrids will be important too ls to elucidate the inheritance of rhizomes in L. corniculatus. Select ion among the hybrids could lead to autogamous, rhizomatous cultivars of L. corniculatus.