01626nam a2200205 a 450000100080000000500110000800800410001910000170006024500990007726001200017630000140029652009800031065000160129065000110130665000320131765300220134965300100137170000220138170000170140319927852014-08-18       2013    bl uuuu     u00u1 u    #d1 aSHOCK, C. C.  aReview of two decades of progress in the development of successful drip irrigation for onions.  aIn: IRRIGATION SHOW & EDUCATION CONFERENCE, 2013, Austin. Proceedings... Falls Church: Irrigation Associationc2013  c1 CD-ROM.  aThe irrigation needs of long day onion (Allium cepa) have been extensively studied at Ontario, Oregon, over the past 22 years. Drip irrigation has compared favorably with furrow and sprinkler irrigation systems. Onions were found to have very narrow soil moisture requirements. Drier soil than optima led to yield loss and wetter soil promoted bulb decomposition. Short term water stress at the three- to six-leaf stages of plant growth promoted multiple centers in long day onion varieties. Irrigation was successfully scheduled using soil water tension or evapotranspiration. Nitrogen fertilization and plant populations have been optimized. Drip system design must carefully consider the hydraulic conductivity of the soil in the placement of tape and onion rows since the soil moisture must wick over from the drip tape to the onion plant. The drip irrigation system design uniformity, operation, and maintenance are essential given onion?s low tolerance to water stress.  aAllium Cepa  aCebola  aIrrigação por Gotejamento  aEstresse hídrico  aOnion1 aFEIBERT, E. B. G.1 aPINTO, J. M.