02393naa a2200289 a 450000100080000000500110000800800410001902400350006010000210009524501550011626000090027152014990028065000190177965000150179865000130181365000250182665000170185165000240186865000220189265000160191465300290193065300220195965300190198170000170200070000170201777300690203419867302020-01-08       2014    bl uuuu     u00u1 u    #d7 a10.1007/s12355-013-0267-02DOI1 aNASSIF, D. S. P.  aEvapotranspiration and transpiration coupling to the atmosphere of sugarcane in southern Brazilbscaling up from leaf to field.h[electronic resource]  c2014  aAbstract In some of the traditional areas growing sugarcane and in most of the expanding regions in Brazil, water deficit stress is a limiting factor and irrigation is usually needed to assure economically viable sugarcane yields. This research evaluated the water requirements of a drip-irrigated second ratoon sugarcane crop based on three different spatial scales: field, plant and leaf. The Bowen atio method (BRM) was used to evaluate the mass and energy exchanges over the field, further computing the crop evapotranspiration (ETc). Sap flow by heat balance method nstalled in four representative stalks was used to evaluate he water use at the plant scale, and an infra-red gas analyser was used to evaluate leaf transpiration and stomatal conductance at the leaf scale. Comparing ETc and reference evapotranspiration we found that the crop coefficients or dry and wet seasons were 0.81 and 0.98, respectively. Evapotranspiration peaks of 7 mm day-1 were observed under conditions of strong crop-atmosphere coupling and high net radiation values. The stomatal conductance ranged from 0.09 to 0.19 mmol m-2 s-1 in dry and wet seasons respectively, showing sensitivity to the atmospheric conditions, notably the vapour deficit pressure and wind speed. BRM ranged from 3.7 to 4.4 mm day-1 and leaf transpiration ranged among 3.4 and 4.2 mm day-1. In an irrigated sugarcane production area in Brazil, water consumption of the sugarcane crop was highly correlated with atmospheric conditions.  aEnergy balance  aIrrigation  aSap flow  aStomatal conductance  aWater stress  aBalanço de Energia  aBalanço hídrico  aIrrigação  aCondutância estomática  aEstresse hídrico  aFluxo de seiva1 aMARIN, F. R.1 aCOSTA, L. G.  tSugar Tech, New Delhigv. 16, n. 3, p. 250-254, July/Sept. 2014.