We have identified two Rhizobium meliloti genes (nodD2 and nodD3) that are highly homologous and closely linked to the regulatory gene nodD (nodD1). R. meliloti strains containing mutations in the three nodD genes in all possible combinations were constructed and their nodulation phenotypes were assayed on Medicago sativa (alfalfa) and Melilotus alba (sweet clover). A triple nodD1-nodD2-nodD3 m...

The ch4 mutant of sweetclover (Melilotus alba) has previously been demonstrated to be temperature- and photoperiod-sensitive for the accumulation of chlorophyll. Pigment content of ch4 mutant leaves was examined as a function of trifoliolate mass, an index of leaf development. Inhibition of chlorophyll accumulation caused by increased growth temperature or decreased photoperiod can be attenuate...

Leaflet orientation in Melilotus indicus (L.) All. Is under photonastic control during the day and nyctinastic control during the night, but also exhibits a diaphototropic (solar-tracking) response. Detached leaves with the two lateral leaflets excised were used to study the solar-tracking capability of the terminal leaflet. Perception of the photonastic excitation is located in the pulvinule. ...

This paper describes an open-flower mutant, designated opf, that we discovered in a genetic screen of fast neutron bombardment mutants in an attempt at floral-dip transformation of Melilotus alba (Fabaceae; white sweetclover), an alternative papilionoid legume host for Sinorhizobium meliloti. The opf mutant developed flowers with reflexed sepals and petals, thereby exposing the stamens and carp...