Graded allocation between vegetative and reproductive growth for annual plants in growing seasons of random length

Abstract Optimal allocation strategies are calculated for annual plants in fluctuating environments using a two-component model of plant growth, in which photosynthate is partitioned between a vegetative and a reproductive component. Previous studies have shown that final reproductive yield is maximized by a sequence of complete switches from purely vegetative to purely reproductive growth in an environment of fixed length. In most cases this final yield is maximized by a single switch. Here we assume that in temporally varying environments natural selection acts to maximize the geometric mean of final yield. We show that the geometric mean of final yield is maximized by a graded allocation strategy that prescribes a mix of vegetative and reproductive growth. Examples of graded optimal allocation strategies are provided.

[1]  O. T. Solbrig.  The Population Biology of Dandelions , 1971 .

[2]  J. C. Beatley.  Survival of Winter Annuals in the Northern Mojave Desert. , 1967, Ecology.

[3]  G. Leitmann.  An Introduction To Optimal Control , 1966 .

[4]  T. Vincent,et al.  Evolution of life history strategies for an asexual annual plant model. , 1980, Theoretical population biology.

[5]  Madhav Gadgil,et al.  The Concept of r- and K-Selection: Evidence from Wild Flowers and Some Theoretical Considerations , 1972, The American Naturalist.

[6]  Harold A. Mooney,et al.  The Carbon Balance of Plants , 1972 .

[7]  J. C. Beatley.  Biomass of desert winter annual plant populations in southern Nevada , 1969 .

[8]  E. Wilson,et al.  Caste and ecology in the social insects. , 1979, Monographs in population biology.

[9]  D. Cohen,et al.  Maximizing final yield when growth is limited by time or by limiting resources. , 1971, Journal of theoretical biology.

[10]  J. C. Beatley.  Phenological Events and Their Environmental Triggers in Mojave Desert Ecosystems , 1974 .

[11]  G. Paltridge,et al.  Plant yield and the switch from vegetative to reproductive growth. , 1974, Journal of theoretical biology.

[12]  J. Roughgarden,et al.  Multiple switches between vegetative and reproductive growth in annual plants , 1982 .

[13]  R. Lewontin,et al.  On population growth in a randomly varying environment. , 1969, Proceedings of the National Academy of Sciences of the United States of America.

[14]  J. C. Hickman.  ENERGY ALLOCATION AND NICHE DIFFERENTIATION IN FOUR CO-EXISTING ANNUAL SPECIES OF POLYGONUM IN WESTERN NORTH AMERICA , 1977 .

[15]  D. Cohen.  Optimizing reproduction in a randomly varying environment. , 1966, Journal of theoretical biology.

[16]  K. Bell,et al.  Seasonal changes in biomass allocation in eight winter annuals of the Mojave Desert , 1979 .

[17]  J. P. Mcdanell,et al.  Necessary Conditions Joining Optimal Singular and Nonsingular Subarcs , 1971 .

[18]  J. Harper,et al.  The reproduc-tive strategy of higher plants. 1. The concept of strategy with special reference to Senecio vulgaris L. , 1970 .