Development of two sequence-specific PCR markers linked to the le gene that reduces pod shattering in narrow-leafed Lupin (Lupinus angustifolius L.)

Jeffrey G Boersma,Bevan J Buirchell,Krishnapillai Sivasithamparam,Huaan Yang

doi:10.1590/s1415-47572007000400020

Abstract

Wild types of narrow-leaf lupin (Lupinus angustifolius L.) have seed pods that shatter upon maturity, leading to the loss of their seeds before or during the harvest process. Two recessive genes have been incorporated into domesticated cultivars of this species to maximize harvest-ability of the produce. One of these genes is called lentus (le). Two microsatellite - anchored fragment length polymorphism (MFLP) candidate markers were identified as closely linked to the le gene in a recombinant inbred line (RIL) population derived from a domesticated x wild type cross. The candidate MFLP markers were isolated from the gel, re-amplified by PCR, cloned and sequenced. The MFLP polymorphisms were converted into sequence-specific PCR-based markers. Linkage analysis by MapManager indicated that one of the markers, LeM1, was 2.6 centiMorgans (cM) and the other, LeM2, was 1.3 cM from the gene, with both being on the same side. The correlation between the marker genotype and the plant phenotype for the le gene is 95% for the Australian cultivars, and approximately 36% on wild types tested. These markers may be useful in marker assisted selection for the le gene when introgressing wild material into lupin breeding programs.

Highlights

An essential characteristic of a modern grain crop is the ability to retain its seeds long enough to allow mechanical harvesting at full maturity
Among the markers originated from 153 sets of microsatellite – anchored fragment length polymorphism (MFLP) during a mapping study (Boersma et al, 2005), two dominant markers designated as DAWA323.150 and DAWA468.290 were identified as candidate markers for development as sequence-specific markers tagging the le gene
Marker DAWA323.150 mapped as1.2 cM from the le gene in the map based on the 89 recombinant inbred line (RIL) (Boersma et al, 2005), was present in RILs with lele genotype, but was absent in RILs with LeLe genotype (Figure 1)

Summary

Introduction

An essential characteristic of a modern grain crop is the ability to retain its seeds long enough to allow mechanical harvesting at full maturity. Introduced into Western Australia (W.A.) towards the end of the 19th century (Gladstones, 1994) as a green manure crop, these plants were essentially wild. Wild types of L. angustifolius have seed pods that shatter upon maturity, making harvesting very difficult. Research aimed at finding plants with non-shattering pods was reported to have begun in Germany in 1929 (Hanelt, 1960). They were successful in selecting a strain that had a reduced pod shatter (von Sengbusch and Zimmermann, 1937) apparently related to a large reduction in the thick-

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