Chemical Defense of Lupins. Mollusc-Repellent Properties of Quinolizidine Alkaloids

Abstract

Quinolizidine Alkaloids, M ollusc Repellency, C oevolution, Plant-H erbivore Interaction, Snails, Chemical Defense Polyphagous molluscs such as H elix pom atia and Arion rufus generally do not feed on plants containing alkaloids. O f 19 species tested 10 species were totally avoided, the other 9 species were less attacked than Lactuca sativa, which was readily taken. Plants containing quinolizidine alkaloids were studied in detail. Those species with the a-pyridone alkaloids cytisine and N-methylcytisine were avoided to a higher extent than plants with lupanine as the major alkaloid. Since the repellency observed could be due to other natural products present in the plants besides the alkaloids, the feeding response o f H elix pom atia was tested on artificial diets containing quinolizidine alkaloids in various concentrations as the only variable. If the snails had the choice they clearly preferred alkaloid-free food or a diet with only low alkaloid concen trations. Half-maximal repellency o f cytisine is less than 2 m M , o f sparteine 1 -5 m M , and o f lupanine 1 -8 mM. Since the in vivo concentrations o f sparteine, cytisine, and lupanine are equal to or higher than the inhibitory concentrations required it is concluded that quinolizidine alkaloids constitute a potential antimolluscan principle o f legum es.

The bacterial artificial chromosome (BAC) library of the narrow-leafed lupin (Lupinus angustifolius L.)

“…Furthermore, lupins are characterized by a rich secondary metabolism and the production of alkaloids, phytoalexins and flavonoids [7,8]. Some of these biologically active substances have potential applications in medicine and in pest control [9,10]. Despite their obvious advantages as a crop, lupins are still of minor importance in Europe.…”

Effect of Lupin Extract and Nitrogen Fertilization on Yield Quality of Celeriac

“…It was also observed that lupin extract exhibits repellent activity against Colorado beetle (Wyrostkiewicz et al 1996) as well as bacteriostatic (Tyski et al 1988, Wink 1994, and fungistatic activity (Wink 1994). Cwojdziński et al (1997) believe that, the extract has positive effect on yield when optimal growing conditions during plant cultivation are ensured i.e.…”

“…It seems that explanation of action mode of lupin extract should be looked for in its chemical composition, in particular relatively high amount of alkaloids (95.8 g⋅kg -1 ). It may be supposed that so-called minor alkaloids, present also in lupin extract, play very important role of stimulators of photosynthesis process (Wink 1994). According to this author, in plants sprayed with solution of alkaloids photosynthesis may be intensified supplying plants with additional carbohydrates, which may be used as an energy source for nitrates reduction.…”

“…It should be underlined that with lupin extract plants were supplied with relatively big amounts of both manganese (190 mg·kg -1 ) and molybdenum (6 mg·kg -1 ). Another compounds, which activate nitrate reductase and also stimulate synthesis of nitrogen compounds, in particular ribonucleic acids and proteins, are cytokinins (Wink 1994). It may not be excluded that extract from bitter lupin contains dihydrozeatin, a chemical from cytokinin group, which presence in seeds of yellow lupin was reported by Koshimizu et al (1997).…”

Larval Performance and Adult Attraction ofDelia platura(Diptera: Anthomyiidae) in a Native and an Introduced Crop

“…Quinolizidine alkaloids are plant defensive compounds against herbivores (Wink 1984, 1992a, Wink and Römer 1986. There are high concentrations of these alkaloids in seeds of lupines (1-4% of dried weight) (Wink 1992a, Carey andWink 1994).…”