Topic
Lupinus arizonicus
About: Lupinus arizonicus is a research topic. Over the lifetime, 4 publications have been published within this topic receiving 259 citations.
Papers
TL;DR: In this paper, the gas exchange responses of potted, outdoor and greenhouse grown plants of the Sonoran Desert annuals Lupinus arizonicus (Wats.) and Malvastrum rotundifolium (Gray) were examined.
Abstract: The gas exchange responses of potted, outdoor and greenhouse grown plants of the Sonoran Desert annuals Lupinus arizonicus (Wats.) and Malvastrum rotundifolium (Gray) were examined. Light saturation of leaf photosynthetic rates did not occur in either species at quantum flux densities exceeding 2.0 mmol m-2 s-1. Decreasing water potentials due to long-term drought did not alter this pattern of light response, though it did lower both photosynthetic rates and leaf conductances. Absolute maximum net photosynthetic rates exceeded 60 μmol m-2 s-1 and 50 μmol m-2 s-1 for M. rotundifolium and L. arizonicus, respectively. Both species showed a two level control of leaf conductance, responding to bulk leaf water potential and vapor pressure deficit. There were non-stomatal effects of drought upon photosynthesis in each species. Leaves of M. rotundifolium exhibited a constant stomatal, inhibition of approximately 19%, while in leaves of L. arizonicus stomatal inhibition ranged from 12–40% with decreasing leaf water potentials. These physiological data lend support to previous reports on the divergent water use patterns of these co-occurring species.
121 citations
TL;DR: Evidence is presented that an active K+ ion transport mechanism is involved in these turgor-related leaf movements and there was an increase in the cupping leaf movement which is shown to be a water stress response.
Abstract: A B S T R A C T Both diaheliotropic (sun-tracking) and paraheliotropic (cupping) leaf movements are described for the Arizona Lupine [Lupinus arizonicus (Wats.) Wats.]. The leaf movements are shown to be non-circadian in nature. Evidence is presented that an active K+ ion transport mechanism is involved in these turgor-related leaf movements. Increasing concentrations of lanthanum, a known ion transport inhibitor, showed increasing inhibition of both leaf movements. Increasing concentrations of other salts did not inhibit either leaf movements, instead there was an increase in the cupping leaf movement (elevation of the leaflets) which is shown to be a water stress response.
75 citations
TL;DR: Diurnal patterns of leaf conductance showed marked seasonal trends, with gas exchange activity being restricted to early morning hours as water availability declined, and the significance of the two contrasting patterns is discussed in terms of observed plant distribution and origin.
Abstract: The seasonal course of water relations in field populations of two leaf solar tracking desert winter annuals was examined. Measurements were made of leaf movements in relation to leaf conductance and water potential. Malvastrum rotundifolium maintained solar tracking movements up to the wilting point of the plant (-4 MPa). Lupinus arizonicus altered its morphology through paraheliotropic leaf movements as leaf water potentials declined to-1.8 MPa. Diurnal patterns of leaf conductance showed marked seasonal trends, with gas exchange activity being restricted to early morning hours as water availability declined. Studies of potted plants showed that L. arizonicus was not able to alter its osmotic potential in response to drought, while M. rotundifolium underwent a 1.86 MPa reduction in osmotic potential. The significance of the two contrasting patterns is discussed in terms of observed plant distribution and origin.
69 citations
12 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 1983 | 1 |
| 1982 | 1 |
| 1978 | 1 |
| 1977 | 1 |