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Plant Responses to Light: A Potential Tool for Weed Management

Published online by Cambridge University Press:  12 June 2017

Jodie S. Holt
Jodie S. Holt*
Affiliation:
Dep. Botany and Plant Sci., Univ. California, Riverside, CA 92521-0124
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Abstract

Light regulates many facets of plant growth and development through the effects of quantity of total energy and of photons, spectral quality, duration, and photoperiod. Numerous techniques and types of equipment are available for quantifying light in plant canopies. The effect of total quantity of light on weed and crop productivity has been described for many cropping systems. Recent work has focused on other aspects of light, in particular, spectral distribution of light (quality), transient light (sunflecks), and plant adaptation to changing light environments. The altered spectral quality of light in a plant canopy affects plant growth and morphology, which in turn affect competition for light. Dynamic plant response to transient light is also important to canopy photosynthesis and productivity. Plant physiological and morphological adaptation to fluctuating light is another potential factor regulating weed/crop interactions. Current cropping practices such as using smother crops and narrow row spacing exploit plant light responses to promote crop growth and suppress weed growth. A better understanding of plant responses to light quality, transient light, and fluctuating light environments will lead to a better understanding of how to manipulate the light environment in crop canopies to improve weed management.

Keywords

Light qualitysunfleckstransient lightcanopycompetitionphotosynthesiscultural weed control
Type
Special Topics
Information
Weed Science , Volume 43 , Issue 3 , September 1995 , pp. 474 - 482
Copyright
Copyright © 1995 by the Weed Science Society of America 

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References

LITERATURE CITED

1. Abernathy, J. R. and Bridges, D. C. 1994. Research priority dynamics in weed science. Weed Technol. 8:396–399.Google Scholar
2. Akey, W. C., Jurik, T. W., and Dekker, J. 1990. Competition for light between velvetleaf (Abutilon theophrasti) and soybean (Glycine max). Weed Res. 30:403–411.Google Scholar
3. Aldrich, R. J. 1984. Weed-Crop Ecology. Breton Publ., North Scituate, MA. Pages 373–435.Google Scholar
4. Anderson, J. M., Goodchild, D. J., and Boardman, N. K. 1973. Composition of the photosystems and chloroplast structure in extreme shade plants. Biochim. Biophys. Acta 325:573–585.Google Scholar
5. Arntz, B. and Trebst, A. 1986. On the role of the QB protein of PS II in photoinhibition. FEBS Lett. 194:43–49.Google Scholar
6. Ballare, C. L., Sanchez, R. A., Scopel, A. L., Casal, J. J., and Ghersa, C. M. 1987. Early detection of neighbour plants by photochrome perception of spectral changes in reflected sunlight. Plant, Cell Environ. 10:551–557.Google Scholar
7. Ballare, C. L., Sanchez, R. A., Scopel, A. L., and Ghersa, C. M. 1988. Morphological responses of Datura ferox L. seedlings to the presence of neighbours. Oecol. 76:288–293.Google Scholar
8. Ballare, C. L., Scopel, A. L., Radosevich, S. R., and Kendrick, R. E. 1990. Phytochrome-mediated phototropism in de-etiolated seedlings. Plant Physiol. 100:170–177.Google Scholar
9. Ballare, C. L., Scopel, A. L., and Sanchez, R. A. 1990. Far-red radiation reflected from adjacent leaves: an early signal of competition in plant canopies. Sci. 247:329–332.Google Scholar
10. Ballare, C. L., Scopel, A. L., and Sanchez, R. A. 1991. On the opportunity cost of the photosynthate invested in stem elongation reactions mediated by phytochrome. Oecol. 86:561–567.CrossRefGoogle ScholarPubMed
11. Ballare, C. L., Scopel, A. L., and Sanchez, R. A. 1991. Photocontrol of stem elongation in plant neighbourhoods: effects of photon fluence rate under natural conditions of radiation. Plant, Cell Environ. 14:57–65.Google Scholar
12. Ballare, C. L., Scopel, A. L., Sanchez, R. A., and Radosevich, S. R. 1992. Photomorphogenic processes in the agricultural environment. Photochem. Photobiol. 56:777–788.Google Scholar
13. Barnes, P. W., Beyschlag, W., Ryel, R., Flint, S. D., and Caldwell, M. M. 1990. Plant competition for light analyzed with a multispecies canopy model. III. Influence of canopy structure in mixtures and monocultures of wheat and wild oat. Oecol. 82:560–566.Google Scholar
14. Bauer, H. and Thoni, W. 1988. Photosynthetic acclimation in fully developed leaves of the juvenile and adult life phases of Hedera helix . Physiol. Plant. 73:31–37.Google Scholar
15. Bazzaz, F. A. and Carlson, R. W. 1982. Photosynthetic acclimation to variability in the light environment of early and late successional plants. Oecol. 54:313–316.Google Scholar
16. Berkowitz, A. R. 1988. Competition for resources in weed-crop mixtures. Pages 89–119 in Altieri, M. A. and Liebman, M., eds. Weed Management in Agroecosystems: Ecological Approaches. CRC Press, Boca Raton, FL.Google Scholar
17. Beuerlein, J. E. and Pendleton, J. W. 1971. Photosynthetic rates and light saturation curves of individual soybean leaves under field conditions. Crop Sci. 11:217–219.Google Scholar
18. Beyschlag, W., Barnes, P. W., Ryel, R., Caldwell, M. M., and Flint, S. D. 1990. Plant competition for light analyzed with a multispecies canopy model. II. Influence of photosynthetic characteristics on mixtures of wheat and wild oat. Oecol. 82:374–380.Google Scholar
19. Bjorkman, O. and Holmgren, P. 1963. Adaptability of the photosynthetic apparatus to light intensity in ecotypes from exposed and shaded habitats. Physiol. Plant. 16:889–914.Google Scholar
20. Boardman, N. K. 1977. Comparative photosynthesis of sun and shade plants. Ann. Rev. Plant Physiol. 28:355–377.Google Scholar
21. Boyd, J. W. and Murray, D. S. 1982. The effect of shade on silverleaf nightshade (Solanum elaeagnifolium). Weed Sci. 30:264–269.Google Scholar
22. Boyer, J. S. 1982. Plant productivity and environment. Sci. 218:443–448.Google Scholar
23. Bugbee, B. G. and Salisbury, F. B. 1988. Exploring the limits of crop productivity. I. Photosynthetic efficiency of wheat in high irradiance environments. Plant Physiol. 88:869–878.Google Scholar
24. Burkey, K. O. and Wells, R. 1991. Response of soybean photosynthesis and chloroplast membrane function to canopy development and mutual shading. Plant Physiol. 97:245–252.Google Scholar
25. Burton, G. W., Jackson, J. E., and Knox, F. E. 1959. The influence of light reduction upon the production, persistence and chemical composition of coastal bermudagrass (Cynodon dactylon). Agron. J. 51:537–542.Google Scholar
26. Campbell, G. S. and Norman, J. M. 1989. The description and measurement of plant canopy structure. Pages 1–19 in Russell, G., Marshall, B., and Jarvis, P. G., eds. Plant Canopies: Their Growth, Form and Function. Cambridge Univ. Press, Cambridge, GB.Google Scholar
27. Casal, J. J., Deregibus, V. A., and Sanchez, R. A. 1985. Variations in tiller dynamics and morphology in Lolium multiflorum Lam. vegetative and reproductive plants as affected by differences in red/far-red irradiation. Ann. Bot. 56:553–559.Google Scholar
28. Casal, J. J., Sanchez, R. A., and Deregibus, V. A. 1986. The effect of plant density on tillering: the involvement of R/FR ratio and the proportion of radiation intercepted per plant. Environ. Exp. Bot. 26:365–371.Google Scholar
29. Casal, J. J., Sanchez, R. A., and Deregibus, V. A. 1987. The effect of light quality on shoot extension growth in three species of grasses. Ann. Bot. 59:1–7.Google Scholar
30. Casal, J. J., Sanchez, R. A., and Deregibus, V. A. 1987. Tillering responses of Lolium multiflorum plants to changes of red/far-red ratio typical of sparse canopies. J. Exp. Bot. 38:1432–1439.Google Scholar
31. Casal, J. J. and Smith, H. 1989. The function, action and adaptive significance of phytochrome in light-grown plants. Plant, Cell Env. 12:855–862.Google Scholar
32. Chabot, B. F., Jurik, T. W., and Chabot, J. F. 1979. Influence of instantaneous and integrated light-flux density on leaf anatomy and photosynthesis. Amer. J. Bot. 66:940–945.Google Scholar
33. Chazdon, R. L. 1988. Sunflecks and their importance to forest understory plants. Adv. Ecol. Res. 18:1–63.Google Scholar
34. Chazdon, R. L. and Pearcy, R. W. 1986. Photosynthetic responses to light variation in rain forest species. I. Induction under constant and fluctuating light conditions. Oecol. 69:517–523.Google Scholar
35. Chazdon, R. L. and Pearcy, R. W. 1986. Photosynthetic responses to light variation in rain forest species. II. Carbon gain and light utilization during lightflecks. Oecol. 69:524–531.Google Scholar
36. Chazdon, R. L. and Pearcy, R. W. 1991. The importance of sunflecks for forest understory plants. BioSci. 41:760–766.Google Scholar
37. Chow, W. S. and Anderson, J. M. 1987. Photosynthetic responses of Pisum sativum to an increase in irradiance during growth. I. Photosynthetic activities. Aust. J. Plant Physiol. 14:1–8.Google Scholar
38. Cleland, R. E., Melis, A., and Neale, P. J. 1986. Mechanism of photoinhibition: photochemical reaction center inactivation in system II of chloroplasts. Photosyn. Res. 9:79–88.Google Scholar
39. Cooper, J. P. 1975. Control of photosynthetic production in terrestrial systems. Pages 593–622 in Cooper, J. P., ed. Photosynthesis and Productivity in Different Environments. Cambridge Univ. Press, Cambridge, GB.Google Scholar
40. Cornic, G. and Miginiac-Maslow, M. 1985. Photoinhibition of photosynthesis in broken chloroplasts as a function of electron transfer rates during light treatment. Plant Physiol. 78:724–729.Google Scholar
41. Cudney, D. W., Jordan, L.S., and Hall, A. E. 1991. Effect of wild oat (Avena fatua) infestations on light interception and growth rate of wheat (Triticum aestivum). Weed Sci. 39:175–179.CrossRefGoogle Scholar
42. Dale, M. P. and Causton, D. R. 1992. The ecophysiology of Veronica chamaedrys, V. montana, and V. officinalis. I. Light quality and light quantity. J. Ecol. 80:483–492.Google Scholar
43. Dall'Armellina, A. A. and Zimdahl, R. L. 1988. Effect of light on growth and development of field bindweed (Convolvulus arvensis) and Russian knapweed (Centaurea repens). Weed Sci. 36:779–783.Google Scholar
44. Davies, E. C., Chow, W. S., LeFay, J. M., and Jordan, B. R. 1986. Acclimation of tomato leaves to changes in light intensity: Effects on the function of the thylakoid membrane. J. Exp. Bot. 37:211–220.Google Scholar
45. De la Torre, W. R. and Burkey, K. O. 1990. Acclimation of barley to changes in light intensity: Photosynthetic electron transport activity and components. Photosyn. Res. 24:127–136.Google Scholar
46. De la Torre, W. R. and Burkey, K. O. 1990. Acclimation of barley to changes in light intensity: chlorophyll organization. Photosyn. Res. 24:117–125.Google Scholar
47. Demmig-Adams, B. and Adams, W. W. III. 1993. The xanthophyll cycle, protein turnover, and the high light tolerance of sun-acclimated leaves. Plant Physiol. 103:1413–1420.Google Scholar
48. Demmig-Adams, B., Winter, K., Kruger, A., and Czygan, F.-C. 1989. Light response of CO2 assimilation, dissipation of excess excitation energy, and zeaxanthin content of sun and shade leaves. Plant Physiol. 90:881–886.Google Scholar
49. Dengler, N. G. 1980. Comparative histological basis of sun and shade leaf dimorphism in Helianthus annuus . Can. J. Bot. 58:717–730.Google Scholar
50. Deregibus, V. A., Sanchez, R. A., and Casal, J. J. 1983. Effects of light quality on tiller production in Lolium spp. Plant Physiol. 72:900–902.Google Scholar
51. Deregibus, V. A., Sanchez, R. A., Casal, J. J., and Trlica, M. J. 1985. Tillering responses to enrichment of red light beneath the canopy in a humid natural grassland. J. Appl. Ecol. 22:199–206.Google Scholar
52. Donald, C. M. 1961. Competition for light in crops and pastures. Page 282–313 in Mechanisms in Biological Competition. Soc. Exp. Biol. Symposia 15. Academic Press, New York, NY.Google Scholar
53. Fay, P. A. and Knapp, A. K. 1993. Photosynthetic and stomatal responses of Avena sativa (Poaceae) to a variable light environment. Amer. J. Bot. 80:1369–1373.Google Scholar
54. Fitter, A. H. and Hay, R. K. M. 1987. Environmental Physiology of Plants. Academic Press, NY. Pages 23–65.Google Scholar
55. Gamon, J. A. and Pearcy, R. W. 1990. Photoinhibition in Vitis californica. The role of temperature during high-light treatment. Plant Physiol. 92:487–494.Google Scholar
56. Gibbs, M. and Carlson, C. (eds.). 1985. Crop Productivity: Research Imperatives Revisited. An international conference held October 13–18, 1985 at Harbor Springs, MI and December 11–13, 1985 at Airlie, VA.Google Scholar
57. Graham, P. L., Steiner, J. L., and Weise, A. F. 1988. Light absorption and competition in mixed sorghum-pigweed communities. Agron. J. 80:415–418.Google Scholar
58. Greer, D. H., Berry, J. A., and Bjorkman, O. 1986. Photoinhibition of photosynthesis in intact bean leaves: role of light and temperature, and requirement for chloroplast protein synthesis during recovery. Planta 168:253–260.Google Scholar
59. Hatch, M. D., Slack, C. R., and Bull, T. A. 1969. Light-induced changes in the content of some enzymes of the C4-dicarboxylic acid pathway of photosynthesis and its effect on other characteristics of photosynthesis. Phytochem. 8:697–706.Google Scholar
60. Hatfield, J. L. and Carlson, R. E. 1978. Photosynthetically active radiation, CO2 uptake, and stomatal diffusive resistance profiles within soybean canopies. Agron. J. 70:592–596.Google Scholar
61. Havaux, M. 1992. Stress tolerance of photosystem II in vivo. Antagonistic effects of water, heat, and photoinhibition stresses. Plant Physiol. 100:424–432.Google Scholar
62. Heber, U. and Walker, D. 1992. Concerning a dual function of coupled cyclic electron transport in leaves. Plant Physiol. 100:1621–1626.Google Scholar
63. Holmes, M. G. and Smith, H. 1975. The function of phytochrome in plants growing in the natural environment. Nature 254:512–514.Google Scholar
64. Holmgren, P. 1968. Leaf factors affecting light-saturated photosynthesis in ecotypes of Solidago virgaurea from exposed and shaded habitats. Physiol. Plant. 21:676–698.Google Scholar
65. Holt, J. S. 1991. Applications of physiological ecology to weed science. Weed Sci. 39:521–528.Google Scholar
66. Holt, J. S. 1994. Impact of weed control on weeds: New problems and research needs. Weed Technol. 8:400–402.Google Scholar
67. Holt, J. S. and Orcutt, D. R. 1991. Functional relationships of growth and competitiveness in perennial weeds and cotton (Gossypium hirsutum). Weed Sci. 39:575–584.Google Scholar
68. Horwith, B. 1985. A role for intercropping in modem agriculture. BioSci. 35:286–291.Google Scholar
69. Inoue, E., Uchijima, Z., Udagawa, T., Horie, T., and Kobayashi, K. 1968. Studies on energy and gas exchange within crop canopies. 2. CO2 flux within and above a corn canopy. J. Agric. Met. 23:165–176.Google Scholar
70. Jones, H. G. 1983. Plants and Microclimate. A Quantitative Approach to Environmental Plant Physiology. Cambridge Univ. Press, Cambridge, GB. pp. 9–35.Google Scholar
71. Jones, M.B. 1993. Plant microclimate. Pages 47–64 in Hall, D. O., Scurlock, J. M. O., Bolhar-Nordenkampf, H. R., Leegood, R. C., and Long, S. P., eds. Photosynthesis and Production in a Changing Environment. A Field and Laboratory Manual. Chapman and Hall, London, GB.Google Scholar
72. Jordan, N. 1993. Prospects for weed control through crop interference. Ecol. Appl. 3:84–91.Google Scholar
73. Jurik, T. W., Chabot, J. F., and Chabot, B. F. 1979. Ontogeny of photosynthetic performance in Fragaria virginiana under changing light regimes. Plant Physiol. 63:542–547.Google Scholar
74. Keeley, P. E. and Thullen, R. J. 1978. Light requirement of yellow nutsedge (Cyperus esculentus) and light interception by crops. Weed Sci. 26:10–16.Google Scholar
75. Kim, J. H., Nemson, J. A., and Melis, A. 1993. Photosystem II reaction center damage and repair in Dunaliella salina (green alga). Plant Physiol. 103:181–189.Google Scholar
76. Krause, G. H., Somersalo, S., Zumbusch, E., Weyers, B., and Laasch, H. 1990. On the mechanism of photoinhibition in chloroplasts. Relationship between changes in fluorescence and activity of photosystem II. J. Plant Physiol. 136:472–479.Google Scholar
77. Krupa, Z., Oquist, G., and Gustafsson, P. 1990. Photoinhibition and recovery of photosynthesis in psbA gene-inactivated strains of cyanobacterium Anacystis nidulans . Plant Physiol. 93:1–6.Google Scholar
78. Kyle, D. J., Osmond, C. B., and Arntzen, C. J., eds. 1987. Photoinhibition. Topics in Photosynthesis, Volume 9. Elsevier Science Pub., New York, NY. 315 Pages.Google Scholar
79. Laisk, A., Kiirats, O., and Oja, V. 1984. Assimilatory power (postillumination CO2 uptake in leaves). Measurement, environmental dependencies and kinetic properties. Plant Physiol. 76:723–729.Google Scholar
80. Liebman, M. 1988. Ecological suppression of weeds in intercropping systems. A review. Pages 97–212 in Altieri, M. A. and Liebman, M., eds. Weed Management in Agroecosystems: Ecological Approaches. CRC Press, Boca Raton, FL.Google Scholar
81. Liebman, M. and Dyck, E. 1993. Crop rotation and intercropping strategies for weed management. Ecol. Appl. 3:92–122.Google Scholar
82. Long, S. P. and Humphries, S. 1994. Photoinhibition of photosynthesis in nature. Ann. Rev. Plant Physiol. Plant Molec. Bio. 45:633–662.CrossRefGoogle Scholar
83. Loomis, R. S. and Gerakis, P. A. 1975. Productivity of agricultural ecosystems. Pages 145–172 in Cooper, J. P., ed. Photosynthesis and Productivity in Different Environments. Cambridge Univ. Press, Cambridge, GB.Google Scholar
84. Masojidek, J., Trivedi, S., Halshaw, L., Alexiou, A., and Hall, D. O. 1991. The synergistic effect of drought and light stresses in sorghum and pearl millet. Plant Physiol. 96:198–207.Google Scholar
85. Mbah, B. N., McWilliams, E. L., and McCree, K. J. 1983. Carbon balance of Pepperomia obtusifolia plants during acclimatization to low PPFD. J. Amer. Soc. Hort. Sci. 108:769–773.Google Scholar
86. McGiffen, M. E. Jr., Masiunas, J. B., and Hesketh, J. D. 1992. Competition for light between tomatoes and nightshades (Solanum nigrum or S. ptycanthum). Weed Sci. 40:220–226.Google Scholar
87. McLachlan, S. M., Tollenaar, M., Swanton, C. J., and Weise, S. F. 1993. Effect of corn-induced shading on dry matter accumulation, distribution, and architecture of redroot pigweed (Amaranthus retroflexus). Weed Sci. 41:568–573.Google Scholar
88. McWhorter, C. G. and Barrentine, W. L. 1988. Research priorities in weed science. Weed Technol. 2:2–11.Google Scholar
89. McWhorter, C.G. and Jordan, T.N. 1976. The effect of light and temperature on growth and development of johnsongrass (Sorghum halepense). Weed Sci. 24:88–91.Google Scholar
90. Methy, M., Alpert, P., and Roy, J. 1990. Effects of light quality and quantity on growth of the clonal plant Eichhornia crassipes . Oecol. 84:265–271.Google Scholar
91. Miyachi, S. and Hogetsu, D. 1970. Light-enhanced carbon dioxide fixation in isolated chloroplasts. Plant Cell Physiol. 11:927–936.Google Scholar
92. Monteith, J. L. 1978. Reassessment of maximum growth rates for C3 and C4 crops. Exp. Agric. 14:1–5.Google Scholar
93. Monteith, J. L. 1981. Does light limit crop production? Pages 23–38 in Johnson, C. D., ed. Physiological Processes Limiting Plant Productivity. Butterworths, London, GB.Google Scholar
94. Nobel, P.S. 1976. Photosynthetic rates of sun versus shade leaves of Hyptis emoryi Torr. Plant Physiol. 58:218–223.Google Scholar
95. Nobel, P. S., Forseth, I. N., and Long, S. P. 1993. Canopy structure and light interception. Pages 79–90 in Hall, D. O., Scurlock, J. M. O., Bolhar Nordenkampf, H. R., Leegood, R. C. and Long, S. P., eds. Photosynthesis and Production in a Changing Environment. A Field and Laboratory Manual. Chapman and Hall, London, GB.Google Scholar
96. Novoplansky, A. 1991. Developmental responses of portulaca seedlings to conflicting spectral signals. Oecol. 88:138–140.Google Scholar
97. Novoplansky, A., Cohen, D., and Sachs, T. 1990. How portulaca seedlings avoid their neighbours. Oecol. 82:490–493.Google Scholar
98. Ort, D. R. and Baker, N. R. 1988. Consideration of photosynthetic efficiency at low light as a major determinant of crop photosynthetic performance. Plant Physiol. Biochem. 26:555–565.Google Scholar
99. Pass, R. G. and Hartley, D. E. 1979. Net photosynthesis of three foliage plants under low irradiation levels. J. Amer. Soc. Hort. Sci. 104:745–748.Google Scholar
100. Patterson, D. T. 1979. The effects of shading on the growth and photosynthetic capacity of itchgrass (Rottboellia exaltata). Weed Sci. 27:549–553.Google Scholar
101. Patterson, D. T. 1980. Shading effects on growth and partitioning of plant biomass in cogongrass (Imperata cylindrica) from shaded and exposed habitats. Weed Sci. 28:735–740.Google Scholar
102. Patterson, D. T. 1982. Effects of shading and temperature on showy crotalaria (Crotalaria spectabilis). Weed Sci. 30:692–697.Google Scholar
103. Patterson, D. T. 1982. Shading responses of purple and yellow nutsedges (Cyperus rotundus and C. esculenlus). Weed Sci. 30:25–30.Google Scholar
104. Patterson, D. T. 1985. Comparative ecophysiology of weeds and crops. Pages 101–129 in Duke, S. O., ed. Weed Physiology. Volume I. Reproduction and Ecophysiology. CRC Press, Inc., Boca Raton, FL.Google Scholar
105. Pearcy, R. W. 1990. Sunflecks and photosynthesis in plant canopies. Ann. Rev. Plant Physiol. Plant Mol. Biol. 41:421–453.Google Scholar
106. Pearcy, R. W. 1991. Radiation and light measurements. Pages 97–117 in Pearcy, R. W., Ehleringer, J., Mooney, H. A., and Rundel, P. W., eds. Plant Physiological Ecology. Field Methods and Instrumentation. Chapman and Hall, New York, NY.Google Scholar
107. Pearcy, R. W., Roden, J. S., and Gamon, J. A. 1990. Sunfleck dynamics in relation to canopy structure in a soybean (Glycine max (L.) Merr.) canopy. Agric. Forest Meteor. 52:359–372.Google Scholar
108. Powles, S. B. 1984. Photoinhibition of photosynthesis induced by visible light. Ann. Rev. Plant Physiol. 35:15–44.Google Scholar
109. Radosevich, S. R. and Ghersa, C. M. 1992. Weeds, crops, and herbicides: A modern-day “neckriddle.” Weed Technol. 6:788–795.Google Scholar
110. Radosevich, S. R. and Holt, J. S. 1984. Weed Ecology. Implications for Vegetation Management. John Wiley and Sons, Inc., New York, NY. pp. 139–154.Google Scholar
111. Regnier, E. E., Salvucci, M. E., and Stoller, E. W. 1988. Photosynthesis and growth responses to irradiance in soybean (Glycine max) and three broadleaf weeds. Weed Sci. 36:487–496.Google Scholar
112. Roush, M. L., Jordan, N., and Holt, J. S. 1989. Ecological basis for weed biology in IPM. Pages 137–156 in Glass, E. H., ed. Proc. National IPM Symposium/Workshop on Targeting Research for IPM Implementation. National IPM Coordinating Committee.Google Scholar
113. Russell, G., Jarvis, P. G., and Monteith, J. L. 1989. Absorption of radiation by canopies and stand growth. Pages 21–39 in Russell, G., Marshall, B., and Jarvis, P. G., eds. Plant Canopies: Their Growth, Form, and Function. Cambridge Univ. Press, Cambridge, GB.Google Scholar
114. Ryel, R. J., Barnes, P. W., Beyschlag, W., Caldwell, M. M., and Flint, S. D. 1990. Plant competition for light analyzed with a multispecies canopy model. I. Model development and influence of enhanced UV-B conditions on photosynthesis in mixed wheat and wild oat canopies. Oecol. 82:304–310.Google Scholar
115. Saradadevi, K. and Raghavendra, A. S. 1992. Dark respiration protects photosynthesis against photoinhibition in mesophyll protoplasts of pea (Pisum sativum). Plant Physiol. 99:1232–1237.Google Scholar
116. Schmitt, J. and Wulff, R. D. 1993. Light spectral quality, phytochrome and plant competition. Trends Ecol. Evol. 8:47–51.Google Scholar
117. Sheehy, J. E. 1985. Radiation. Pages 5–28 in Marshall, B. and Woodward, F. I., eds. Instrumentation for Environmental Physiology. Cambridge Univ. Press, Cambridge, GB.Google Scholar
118. Siefermann-Harms, D. 1987. The light-harvesting and protective functions of carotenoids in photosynthetic membranes. Physiol. Plant. 69:561–568.Google Scholar
119. Sims, D. A. and Pearcy, R. W. 1992. Response of leaf anatomy and photosynthetic capacity in Alocasia macrorrhiza (Araceae) to a transfer from low to high light. Amer. J. Bot. 79:449–455.Google Scholar
120. Singh, K. P. and Gopal, B. 1973. The effects of photoperiod and light intensity on the growth of some weeds of crop fields. Pages 77–85 in Slatyer, R. O., ed. Plant Response to Climatic Factors. Proc. Uppsala Symp., UNESCO, Paris, France.Google Scholar
121. Skalova, H. and Krahulec, F. 1992. The response of three Festuca rubra clones to changes in light quality and plant density. Funct. Ecol. 6:282–290.Google Scholar
122. Smith, H. 1982. Light quality, photoperception, and plant strategy. Ann. Rev. Plant Physiol. 33:481–518.Google Scholar
123. Smith, H., Casal, J. J., and Jackson, G. M. 1990. Reflection signals and the perception by phytochrome of the proximity of neighbouring vegetation. Plant, Cell Env. 13:73–78.Google Scholar
124. Solangaarachchi, S. M. and Harper, J. L. 1987. The effect of canopy filtered light on the growth of white clover Trifolium repens . Oecol. 72:372–376.Google Scholar
125. Stitt, M. 1986. Limitation of photosynthesis by carbon metabolism. I. Evidence for excess electron transport capacity in leaves carrying out photosynthesis in saturating light and CO2 . Plant Physiol. 81:1115–1122.Google Scholar
126. Stoller, E. W. and Myers, R. A. 1989. Response of soybeans (Glycine max) and four broadleaf weeds to reduced irradiance. Weed Sci. 37:570–574.Google Scholar
127. Stoller, E. W., Wax, L. M., and Alm, D. M. 1993. Survey results on environmental issues and weed science research priorities within the corn belt. Weed Technol. 7:763–770.Google Scholar
128. Syvertsen, J. P. 1984. Light acclimation in citrus leaves. II. CO2 assimilation and light, water, and nitrogen use efficiency. J. Amer. Soc. Hort. Sci. 109:812–817.Google Scholar
129. Syvertsen, J. P. and Smith, M. L. 1984. Light acclimation in citrus leaves. I. Changes in physical characteristics, chlorophyll, and nitrogen content. J. Amer. Soc. Hort. Sci. 109:807–812.Google Scholar
130. Thompson, L. and Harper, J. L. 1988. The effect of grasses on the quality of transmitted radiation and its influence on the growth of white clover Trifolium repens . Oecol. 75:343–347.Google Scholar
131. Tremmel, D. C. and Bazzaz, F. A. 1993. How neighbor canopy architecture affects target plant performance. Ecol. 74:2114–2124.Google Scholar
132. Vandermeer, J. 1989. The Ecology of Intercropping. Cambridge Univ. Press, UK. 237 Pages.Google Scholar
133. Vidal, D., Griera, E., Marin, P., and Sabido, J. 1990. Anatomical and physiological acclimation of Fatsia japonica leaves to irradiance. Amer. J. Bot. 77:1149–1158.Google Scholar
134. Walker, G. K., Blackshaw, R. E., and Dekker, J. 1988. Leaf area and competition for light between plant species using direct sunlight transmission. Weed Technol. 2:159–165.Google Scholar
135. Wallace, A. and Wallace, G. A. 1993. Limiting factors, high yields, and law of the maximum. Hortic. Rev. 15:409–448.Google Scholar
136. Wallace, L. L. and Dunn, E. L. 1980. Comparative photosynthesis of three gap phase successional tree species. Oecol. 45:331–340.Google Scholar
137. Wild, A., Hopfner, M., Ruhle, W., and Richter, M. 1986. Changes in stoichiometry of photosystem II components as an adaptive response to high-light and low-light conditions during growth. Z. Naturforsch 41:597–603.Google Scholar
138. Wyse, D. L. 1994. New technologies and approaches for weed management in sustainable agriculture systems. Weed Technol. 8:403–407.Google Scholar
139. Yamamoto, H. Y. and Smith, C. M., eds. 1993. Photosynthetic Responses to the Environment. Current Topics in Plant Physiology: An American Society of Plant Physiologists Series, Volume 8. Amer. Soc. Plant Physiol. Rockville, MD. 252 Pages.Google Scholar
140. Yelverton, F. H. and Coble, H. D. 1991. Narrow row spacing and canopy formation reduces weed resurgence in soybeans, Glycine max. Weed Technol. 5:169–174.Google Scholar
141. Zimdahl, R. L. 1980. Weed-Crop Competition: A Review. International Plant Protection Center, Corvallis, OR. 197 Pages.Google Scholar
142. Zimdahl, R. L. 1988. The concept and applications of the critical weed-free period. Pages 145–155 in Altieri, M. A. and Liebman, M., eds. Weed Management in Agroecosystems: Ecological Approaches. CRC Press, Boca Raton, FL.Google Scholar
143. Zimdahl, R. L. 1993. Fundamentals of Weed Science. Academic Press, Inc., New York, NY. Pages 125–130.Google Scholar