000			02915nam a22003253a 4500
001			UPMIN-00003300477
005			20221005141135.0
040			_aDLC _cDLC _dupmin
041			_aeng
090		0	_aLG993.5 2009 _bB4 O38
100			_aOguis, Georgianna Kae Ruiz.
245			_aLong-term weed management, diversity and abundance of broadleaf weeds in a banana plantation in Davao City, Philippines / _cGeorgianna Kae Ruiz Oguis.
300			_a90 leaves.
502			_aThesis (BS Biology) -- University of the Philippines Mindanao, 2009
520			_aWeeds are considered pests by many farmers because they reduce crop yield. Some weed species however, perform useful ecological functions such as providing a habitat for biocontrol agents, nourishing useful microorganisms in the soil and preventing erosion. Appropriate weed management should therefore aim to maintain a certain level of useful weed population and diversity instead of totally eliminating weeds. To determine if this objective can be achieved under two contrasting weed management practice. I report a two-year study on the effects of manual and chemical weed management on the broadleaf weeds in a banana plantation in Davao City, Philippines. The study regularly examined seed banks and monitored the population and biomass of five dominant weed species. In addition, the reproductive biology of the weeds was examined. I found no significant difference in the seed bank counts between manual and chemical plots. The chemical weed management treatment consisting of paraquat and glyphosate, however, consistently and significantly reduced the field counts and biomass of broadleaf weeds compared to the manual treatment. The broadleaf species diversity increased in the chemical plots but decreased in the manual plots. Dominance index generally decreased due to the appearance of previously undetected Drymaria cordata and Acalypha indica, which competed with the dominant and noxious weeds ageratum conyzoids, Bidens pilosa and cleome rutidosperma in the later part of the observation period. Considering the unique characteristics of the weed species, I discussed the ecological significance of the shifts in weed composition resulting from manual and chemical weeding. I conclude that herbicide treatment was ecologically advantageous compared to manual weed control as it has more effectively reduced weed abundance and dominance of noxious weed without concomitantly decreasing weed diversity.
650	1	7	_aBanana plantation.
650	1	7	_aAgeratum conyzoides.
650	1	7	_aParaquat.
650	1	7	_aWeeds.
650	1	7	_aWeed management.
650	1	7	_aBroadleaf weeds.
650	1	7	_aBanana plantation _zDavao City _zPhilippines.
650	1	7	_aWeed diversity.
650	1	7	_aWeed seed longevity.
650	1	7	_aWeed species.
260			_c2009
905			_aFi
905			_aUP
658			_aUndergraduate Thesis _cBIO200, _2BSB
999			_c2296 _d2296