ALLOMETRY AND GROWTH PATTERNS OF scirpus grossus L. ON PEAT

Scirpus grossus L. is a principal rhizomatous weed in the rice fields, drainage and irrigation canals, river banks, abandoned rice fields and wasteland in Malaysia. This study describes the modular dynamics, spatio-temporal growth patterns of aerial plant and sub-terranean rhizome populations of this scourge on fertilized and unfertilized peat soils. The NPK fertilizer application at 100:30:30 ha^-1 resulted in more robust aerial plant growth of S. grossus with 126.75 ramets m^-2 (mean dry aerial bioamass of 2.32 g plant^-1) compared with 117.83 ramets m^-2 (1.63 g plant^-1) in unfertilized plots 24 weeks after planting of the mother plant. Mean ramets mortality was significantly higher in unfertilized plots at 30.3 ramets m^-2, while in the fertilized plots this was only 8.7 ramets m^-2, resulting respective net populations of 116.08 ramets m^-2 and 87.5 ramets m^ -2 in fertilized and unfertilized plots. Flowering set in earlier among ramets in fertilized plots with 51.58 ramets m^-2 vis-a-vis 38.75 ramets m^-2, 24 weeks after transplanting of the mother plant in unfertilized plots. Fertilizer applications did not register any significant difference in mean plant height, chlorophyll contents, and chlorophyll fluorescence measurements vis-a-vis those without fertilizer application. The time- and space-mediated clonal growth of S. grossus did not register any significant preferential directionality and dispersion of aerial plants and their sub-terranean rhizomes irrespective of fertilizer regimes, but rather displaying opportunistic resource capture by aerial and sub-terranean modules.