Asian Journal of Plant Sciences1682-39741812-5697Asian Network for Scientific Information10.3923/ajps.2002.176.179Arabidopsis thaliana]]>DastiAltaf A. Kaniz Fatima Saeed A. Malik 2200212This study examines the rate of change in dry weight and the way in which the change is distributed between various parts of the plants in response to photoperiod. Classical growth analysis was used to study how relative growth rate, net assimilation rate, leaf area ratio, specific leaf area and biomass allocation to leaves, stems, petioles and roots respond to day length. Significant effect of day length was found on almost all the growth parameters except the biomass allocation to roots. The plants grown under 16 hours show higher growth rate (RGR) than those in 8 hours photoperiod. This high RGR is achieved by high net assimilation rate (NAR) and low specific leaf area: a component of leaf area ratio. Low specific leaf area and high NAR reflect the anatomical modifications of leaf in response to day length, which increase the physiological activities per unit leaf area. Plants grown under long day condition invest more biomass to the stems, little to the leaves and show no clear tendency for roots.]]>Abrahamson, W.G. and M.D. Gadgil,1973Solidago, compositae).]]>107651661Anten, N.P.R. and T. Hirose,199987583597Anten, N.P.R. and M.J.A. Werger,1996Amaranthus dubius L: With a size hierarch of individuals.]]>1053037Bjorkman, O.,19811981pp: 57-107pp: 57-107Bunce, J.A.,198644777Causton, D.R. and J.C. Venus,1981Pages: 307Pages: 307Dale, M.P. and D.R. Causton,1992Veronica chamaedrys, V. Montana and V. officinalis. III. Effects of shading on the phenology of biomass allocations-a field experiment.]]>80517526Dijkstra, P. and H. Lambers, 1986Plantago major differing in relative growth rate.]]>113283290Dijkstra, P.,19891989pp: 125-140pp: 125-140Duncan, D.B.,195511142Givnish, T.J.,1982120353381Harpham, N.V.J., A.W.M. Berry, G. Roeda-Hoyos and I. Reskin et al.,1991Arabidopsis thaliana (L.) Heynh.]]>685561Head, G.C.,19731973pp: 237-294pp: 237-294Koning, H.,19891989pp: 101-123pp: 101-123McMahon, T.,197317912011204Menges, E.S.,1987Laportea Canadensis: Adaptive response to the environment or allometric constraints.]]>74551563Meekins, J.F. and B.C. McCarthy,2000Alliaria petiolata to variation in population density, nutrient addition and light availability.]]>88447463Robinson, S.A. and B.C. McCarthy,1999Carya ovata (Juglandaceae) seedlings to experimental sun patches.]]>1416984Roetman, E. and A.A. Sterk,1986Taraxicum in climatic chambers.]]>35522Poorter, H.,19891989pp: 124-135pp: 124-135Salisbury, F.B and C.W. Ross,19863rd Edn.,pp: 426-445pp: 426-445Stutzel, H., D.A. Charles-Edwards and D.F. Beech,198861481487Wilson, J.B.,198861433449