AOBPreview originally published online on April 29, 2005
Annals of Botany 2005 96(1):127-135; doi:10.1093/aob/mci158
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Reproductive Allocation of Biomass and Nitrogen in Annual and Perennial Lesquerella Crops
1 Departamento de Producción Vegetal and 2 IFEVA, Facultad de Agronomía (UBA), Av. San Martín 4453, (1417) Buenos Aires, Argentina and 3 Department of Crop Production and Forestry, University of Lleida, Centre UdL-IRTA, Av. Rovira Roure 191, E-25198 Lleida, Spain
* For correspondence. E-mail ploschuk{at}ifeva.edu.ar
Received: 26 September 2004 Returned for revision: 8 November 2004 Accepted: 24 March 2005 Published electronically: 29 April 2005
• Background and Aims The use of perennial crops could contribute to increase agricultural sustainability. However, almost all of the major grain crops are herbaceous annuals and opportunities to replace them with more long-lived perennials have been poorly explored. This follows the presumption that the perennial life cycle is associated with a lower potential yield, due to a reduced allocation of biomass to grains. The hypothesis was tested that allocation to perpetuation organs in the perennial L. mendocina would not be directly related to a lower allocation to seeds.
• Methods Two field experiments were carried on with the annual Lesquerella fendleri and the iteroparous perennial L. mendocina, two promising oil-seed crops for low-productivity environments, subjected to different water and nitrogen availability.
• Key Results Seed biomass allocation was similar for both species, and unresponsive to water and nitrogen availability. Greater root and vegetative shoot allocation in the perennial was counterbalanced by a lower allocation to other reproductive structures compared with the annual Lesquerella. Allometric relationships revealed that allocation differences between the annual and the perennial increased linearly with plant size. The general allocation patterns for nitrogen did not differ from those of biomass. However, nitrogen concentrations were higher in the vegetative shoot and root of L. mendocina than of L. fendleri but remained stable in seeds of both species.
• Conclusions It is concluded that vegetative organs are more hierarchically important sinks in L. mendocina than in the annual L. fendleri, but without disadvantages in seed hierarchy.
Key words: Lesquerella fendleri, allocation, partitioning, allometry, annuals, perennials, new crops, oil-seed crops, grain crops