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Multiple consumers often attack seeds, seedlings, and adult plants, but their population-level consequences remain uncertain. We examined how insect and small mammal consumers influenced the demography and abundance of the perennial shrub, bush lupine (Lupinus arboreus). In grassland and dune habitats we established replicate experimental lupine populations in 81-[m.sup.2] plots that were either protected from, or exposed to, herbivorous voles and granivorous mice (via fencing) and/or root feeding insects (via insecticide treatment). Populations were initiated with transplanted seedlings in 1999 and 2000. We followed the demography of these cohorts, subsequent generations, and the seed bank for 5.5 years. Voles and insects killed many seedlings in dune (1999 only) and grassland (1999 and 2000) habitats. After 2000, insects and voles had minimal effects on seedling or adult survival. Seed predation by granivorous mice, however, greatly depressed seedling recruitment, resulting in lower adult lupine abundance in control plots vs. those protected from rodents. In grasslands, initial effects of voles and insects on seedling survival produced large differences among treatments in adult plant density and the cumulative number of seeds produced throughout the experiment. Differences among grassland populations in seed rain, however, had little influence on the magnitude of seedling recruitment into this habitat. Instead, recruitment out of a preexisting seed bank compensated for the lack of seed production in populations exposed to consumers. Shading by dense adults in plots protected from consumers limited seedling establishment within these populations. Although differences among populations in cumulative seed rain did not influence adult establishment, populations protected from consumers accumulated substantially larger seed banks than controls. These results illustrate how density dependence, habitat-specific seed dynamics, and particular demographic impacts of consumers interact to shape plant population responseS to consumers. Key words: bush lupine; granivory; insect herbivory; Lupinus arboreus; plant--consumer interactions; plant population dynamics; seed banks; voles.

Cotyledons of Lupinus luteus were sampled from 1 to 21 days after sowing and processed for light microscopy and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Length, width, and surface area of the cotyledons increased gradually until day 10. The thickness of the cotyledons increased from day 7 to 12 and decreased thereafter. Morphometric analyses showed that the increase in length, width, and thickness of the cotyledon was due to cell expansion, and the decrease in thickness of the cotyledon was due to the decrease in the length of abaxial cells and in the total number of cells. Mesophyll development accompanied schizogenous and lysigenous air space formation. There were two structurally distinct types of protein bodies. Protein bodies in five to six layers of cells on the abaxial side did not contain globoids, while globoids were prominent in protein bodies in the center and adaxial side. Storage protein mobilization occurred first in the abaxial side of the cotyledon and proceeded toward the adaxial side. SDS-PAGE analysis showed that proteins ranged from 97 to 14 kD. High molecular weight [alpha]- and [beta]-conglutinins were more abundant in the abaxial region, whereas [gamma]-conglutinin occurred in both abaxial and adaxial regions. In addition, there were five minor bands between 97 and 43 kD unique to abaxial region and five minor bands between 43 and 14 kD unique to adaxial region in the nonreduced protein profiles. The [alpha]- and [beta]-conglutinins began to decrease after imbibition and disappeared by day 7 after sowing. At this stage the subunits of ribulose-1,5-bisphosphate carboxylase/oxygenase and four new minor bands appeared.

A study was carried out to examine the novel inhibitors of lupin diadenosine 5',5'''-[P.sub.1],[P.sub.4]-tetraphosphate ([Ap.sub.4]A) hydrolase discovered by in silico virtual screening. Findings reveal that the compound may interpret a effective lead in the design of specific inhibitors of the plant-like form of [Ap.sub.4]A hydrolases.

The issue of lupine lineages is addressed by searching for possible biographic patterns preserved in nod gene phylogenies, with the help of Bradyrhizobium strains isolated mainly from lupine nodules of native Andean and lowland South American lupines.