[R] Medicago sativaL. (Fabacae).
Fr: Luzerne; Ge: Luzerne; Pt: Luzerna; Sp: Alfalfa; It: Erba medica.
-Perennial plant with a height of 50 to 80 cm, deep roots and a branched stem, exhibiting considerable morphological diversity (*) .
- It is the most cultivated leguminous forage in the world, and it can be found growing naturally at the edge of fields and roads.
- It is sown in pure stands or with a perennial grass.
- Sowing occurs in April-May for a first harvest at the first flowering (July), and a second harvest at the second flowering (early September).
- A lucerne field can be harvested 3 to 6 times per year. Wilting occurs at the flower stage and then about every 5 weeks. Silage is difficult. It is of limited use for grazing because it may induce serious digestive problems in ruminants through the accumulation of fermentation gases in the rumen (bloating), that cannot be released by eructation during rumination. It is sensitive to trampling.
- A field of lucerne can be maintained in full production for 7 years.
- Diseases: those of forage legumes, and particularly the damping-off disease due to Pythium, yellowing and dwarfism due to Verticillium albo-atrum, the desiccation of isolated plants caused by Sclerotinia trifoliorum, clover scorch (Colletotrichum trifolii) which develops primarily in the summer and Ascochyta pinodella which produces brown stains on the stem and leaves.
- Principal European pests: their principal enemies are common to all forage legumes. However, there are numerous specific pests such as the alfalfa flower midge (Contarinia medicaginis) and the alfalfa sprout midge (Dasineura ignorata). Tychius aureolus (Keiswetter) (Col. Curculionidae), and Cydia medicaginis Kouznetsov (Lep. Tortricidae) attack the seeds.
* Lucerne (Minost C.)
a: stem; b: leaf with 3 folioles; c: stipule; d: inflorescence; e: fruit (pod).
HYPPZ on line: Species (scientific names), Pests (common names), Glossary, Crops.
HYP3 : HYPP Phytopathology.