Diversity of weed flora in pineapple plantations of Kerala.
Pineapple is an important foreign exchange crop of Kerala. A study was initiated to survey the pineapple growing areas and identify the weed flora, their habitat preferences and growth habits is a pre-requisite for developing an appropriate weed management strategy. A survey was undertaken in five major pineapple producing districts of Kerala and phytosociological parameters were estimated. The results showed the occurrence of a fairly wide diversity of weeds in pineapple plantations (54 species), with species from 25 families present in almost all the areas surveyed. The highest representation of weeds was observed from the family Asteraceae (10), followed by Poaceae (8) and Fabaceae (5). Highest frequency values were obtained for Mikania micrantha (63), Chromolaena odorata (60), Merremia umbellata (53.3), Mimosa pudica (50), Alternanthera bettzickiana (50), Cyclea peltata (46.6), Centrosema pubescens (43.3), Cleome burmanii (46.6), Commelina diffusa (43.3), and IchInocarpus frutescens (43.3). Mikania micrantha, Chromolaena odorata, Merremia umbellata, Mimosa pudica, Alternanthera bettzickiana, Cyclea peltata, Cleome burmanii, Centrosema pubescens, and Ichinocarpus frutescens. had the highest Relative dominance while Abundance value was higher for Isachne miliacea, Cynodon dactylon, Digitaria ciliaris, Mollugo verticillata, Parthenium hysterophorus, Melochia corchorifolia, Bulbostylis barbata and Cyperus iria.