Seed predation

Janzen, D. H. (1978). The ecology and evolutionary biology of seed chemistry as relates to seed predation. In Biochemical Aspects of Plant and Animal Co-Evolution, ed. J. B. Harborne, pp. 163-206. London Academic Press. 

Inouye, D. W. and Taylor, O. R. (1979). Temperate region plant-ant-seed predator... 

Seeds are an important food source for many insects, birds, and small mammals. Seed predation is usually less in agricultural systems due to the intensive soil disturbance, seed burial by tillage, and lack of habitats for predators. However, studies have found significant weed seed loss by predation when seeds remained on the soil surface. 

Figure 22.1 Examples from two conceptual axes of interactions between flowers and their animal visitors. Axis 1 is a specialization-generalization spectrum of plant-pollinator interactions. Panel A depicts a guild of red Chilean flowers that share one species of hummingbird as a pollinator. In Panel D, a Perideridia umbel is visited by several families of bees, wasps and flies most are effective pollinators. Axis 2 describes relationships in which animals visit flowers for their own reproductive purposes. In panel B, a female Tegiticula moth gathers pollen from anthers of Yucca filamentosa, for which it is both obligate pollinator and seed predator. In panel C, a Drosophila fly (black arrow) is lured by appearance and smell of decaying matter to a deceptive Aristolochia flower, seen in cross-section. Floral scent plays diverse roles along these axes, including pollinator attraction in food- and sex-based mimicry. All photographs were taken by the author.

Bronstein J. L. (1992) Seed predators as mutualists ecology and evolution of the fig/ pollinator interaction. In Insect-Plant Interactions, ed. E. A. Bernays, Vol. IV, pp. 1—44. CRC Press, Boca Raton, FL. 

Steele MA, Knowles T, Bridle K, Simms EL (1993) Tannins and partial consumption of acorns Implications for dispersal of oaks by seed predators. Am Midi Nat 130 229-238... 

Bossard, C. C. (1991). The role of habitat disturbance, seed predation and ant dispersal on establishment of the exotic shrub Cytisus scoparus in California. Am. Midi. Nat. 126,1-13. 

Harvest losses of safflower can be one to live times the recommended seeding rate. Safflower seeds have some short-term sprouting resistance but no seed dormancy, which limits persistence in the soil seed bank. This oilseed is attractive to seed predators, including small mammals and birds (personal observation), which may reduce seed density but may facilitate transport of seed from the field. The distance and amount of seed transported by animals have not been quantified, and the fate of transported seed is unknown. Volunteer populations are restricted to the first follow year in conventional fields. Although they can be controlled by conventional herbicides in subsequent crops, there is the potential for survivors to flower, set viable seed, and contribute to both PMGF and SMGF. 

The seed mortality due to chewing insects is high for the East African population of the shrub Crotalaria pallida. Unexpectedly, it was found that plants with higher levels of alkaloid in the seeds experienced greater seed predation. 

Sheppard, A.W., CuUen, J.M., Aeschlimann, J.P. Predispersal seed predation on Carduus nutans (Asteraceae) ia southern Europe. ActaOecol. 15(5), 529-541 (1994)... 

Bleiler, J. a., G. a, Rosenthal, and D. H. Janzen, Biochemical ecology of canavanine-eating seed predators, Ecology, 69, 427-433 (1988). 

Rosenthal, G. A., C. G. Hughes, and D. H. Janzen, L-Canavanine, a dietary nitrogen source for the seed predator Caryedes bra-siliensis (Bruchidae), Science, 217, 353-355 (1982). 

Brouwer R (1983) Functional equilibrium sense or nonsense Neth J Agric Sci 31 335-348 Bnist GE (1994) Seed-predators reduced broadletif weed growth and competitive ability. Agric Ecosyst and Environ 48 27-34... 

Putnam AR, DeFrank J, Barnes JP (1983) Exploitation of allelopathy for weed control in annual and perennial cropping systems. J Chem Ecol 9 1001-1010 Putnam AR, Tang CS (1986) The science of allelopathy. WUey, New York, NY Qasem IR, Hill TA (1989) On difficulties with allelopathy methodology. Weed Res 29 345-347 Reader RJ (1991) Control of seedling emergence by ground cover a potential mechanism involving seed predation. Can J Bot 69 2084-2087... 

Cineole (Fig. 1) is a major constituent of these plant essential oils and is one of the most potent allelochemicals released by Artemisia spp. [37]. However, the potential allelopathic role of this monoterpene is not clearly established. Other factors such as competitiveness, reduced seed predation, and/or drought tolerance may be more important in the survival of the species [37]. 

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