|JORDA, JR., J|
Submitted to: World Agroforestry Congress
Publication Type: Abstract Only
Publication Acceptance Date: 11/24/2003
Publication Date: 6/29/2004
Citation: Baligar, V.C., Olimpio, J., Paiva, A., Silveria, A., Lucena, E., Faria, J.C., Cabral, R., Pomella, A., Jorda, Jr., J. 2004. Light intensity effects on growth and nutrient uptake and use efficiency of erect leguminous cover crops[abstract]. World Agroforestry Congress.
Technical Abstract: In plantation crops such as cacao, cover crops have tremendous beneficial influence on improved soil fertility and productivity, reduced erosion and leaching losses, and control of weeds, diseases and pests. Because, cover crops are grown as under story plants, light intensity has major implications on the growth, development and survivability of these plants. Information is lacking on the growth performance and nutrient needs of these crops at low light intensities. Experiment was under taken in climatically controlled growth room to assess the influence of photosynthetic photon flux density (PPFD) on growth and macro-micro nutrient uptake parameters (concentration, uptake) and nutrient use efficiency in erect leguminous cover crops. Two PPFD (200, 400 umol s-1 m-2) were achieved by constructing mini shade frames covered with various layers of plastic cloth. Nine cover crops used in this study include: joint vetch, sunhemp, crotolaria ochroleuca, showy crotolaria, hairy indigo, lab-lab, sesbania, tropical stylo-fabaceae and cowpea. Higher PPFD enhanced growth and nutrient uptake parameters and nutrient use efficiency. Cover crops used in this study showed inter specific differences in growth, nutrient uptake and nutrient use efficiency at both the PPFD. Cover crops tested are sensitive to low light intensity. Shade and fertilizer management are very critical in plantation crops to achieve the maximum potentials benefits of cover crops.