Meristem temperature substantially deviates from air temperature, even in moderate environments: Is the magnitude of this deviation species-specific?
Savvides, A. ; Ieperen, W. van; Dieleman, J.A. ; Marcelis, L.F.M. - \ 2013
Plant, Cell & Environment 36 (2013)1. - ISSN 0140-7791 - p. 1950 - 1960.
shoot-tip temperature - climate-change - leaf development - effective thickness - light interception - boundary-layers - heat-transfer - crop yields - maize apex - plant
Meristem temperature (Tmeristem) drives plant development but is hardly ever quantified. Instead, air temperature (Tair) is usually used as its approximation. Meristems are enclosed within apical buds. Bud structure and function may differ across species. Therefore, Tmeristem may deviate from Tair in a species-specific way. Environmental variables (air temperature, vapour pressure deficit, radiation, and wind speed) were systematically varied to quantify the response of Tmeristem. This response was related to observations of bud structure and transpiration. Tomato and cucumber plants were used as model plants as they are morphologically distinct and usually growing in similar environments. Tmeristem substantially deviated from Tair in a species-specific manner under moderate environments. This deviation ranged between -2.6 and 3.8¿°C in tomato and between -4.1 and 3.0¿°C in cucumber. The lower Tmeristem observed in cucumber was linked with the higher transpiration of the bud foliage sheltering the meristem when compared with tomato plants. We here indicate that for properly linking growth and development of plants to temperature in future applications, for instance in climate change scenarios studies, Tmeristem should be used instead of Tair, as a species-specific trait highly reliant on various environmental factors
A parabolic singular perturbation problem with an internal layer
Grasman, J. ; Shih, S.D. - \ 2004
Asymptotic Analysis 38 (2004)4. - ISSN 0921-7134 - p. 309 - 318.
hyperbolic conservation-laws - differential-equations - boundary-layers - weak solutions
A method is presented to approximate with singular perturbation methods a parabolic differential equation for the quarter plane with a discontinuity at the corner. This discontinuity gives rise to an internal layer. It is necessary to match the local solution in this layer with the one in a corner layer as otherwise terms in the internal layer solution remain unnoticed. The problem is explained using the exact solution of a special case. The asymptotic solution is proved to approximate the exact solution in the general case using the maximum principle for parabolic differential equations.