A Model Study of the Alfalfa Leafcutter Bee - Seed Production System PDF Download

Author: Steven Bruce Stark
Publisher:
ISBN:
Category : Alfalfa leafcutting bee
Languages : en
Pages : 232

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Book Description
The behaviors of the alfalfa leaf cutter bee - seed production system under imposition of several management regimes were studied through the use of a simulation model that contains mechanisms for the following processes: 1) immature bee development and diapause; 2) immature bee mortality; 3) female bee emergence; 4) nesting tunnel selection; 5) egg-laying; 6) adult mortality; and 7) flowering and seed production. Management tactics studied through the use of simulation included: 1) varying the number of female bees introduced at the start of the season relative to the flower supply; 2) varying the time of initial bee emergence relative to initial flowering; 3) varying the number of introduced open tunnels relative to the number of introduced female bees; and 4) varying the time of initial system activities (emergence and flowering). The annual resolution model outputs, diapause female bee production and seed production, were studied to reveal the following behaviors: 1) Bee production increases when the initial emergence and flowering are delayed beyond the standard management time. 2) Seed production increases with a two week delay, but decreases with a four week delay. 3) With increasing bee introductions, bee production behaves similarly for both delay tactics, but quite differently for the standard. 4) With increasing bee introductions, seed production increases rapidly to a maximum and then levels off, for all three tactics. 5) The effects on bee and seed productions of asynchrony in first emergence and flowering depend on the timing of the onset of flowering. In almost all circumstances, the flowering delay tactic is better than the standard tactic, but greater asynchrony in the direction of late emergence is best offset by the standard tactic. 6) The introduction of open tunnels with small capacities (rather than large) greatly reduces the rate of bee population increase. The population increase is also greatly reduced when the overall capacity of the introduced open tunnels is insufficient for the population's cell production. 7) Seed production is insensitive to the open tunnel introduction. The identification of key mechanisms for the above behaviors led to the examination of current knowledge of those mechanisms and to the identification of needed research. The model provides a coherent, whole system perspective for management and research applications.