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Maximum daily trunk shrinkage and stem water potential reference equations for irrigation scheduling of lemon trees 总被引:3,自引:2,他引:1
Maria Fernanda Ortuño Juan José Brito Yelitza García-Orellana Wenceslao Conejero Arturo Torrecillas 《Irrigation Science》2009,27(2):121-127
Measurements of midday stem water potential (ψstem) and maximum daily trunk shrinkage (MDS) were done over a 3-year period in adult Fino lemon trees (Citrus
limon (L.) Burm. fil.) grafted on sour orange (C. aurantium L.) rootstocks. Plants were irrigated daily above their water requirements in order to obtain non-limiting soil water conditions.
The results indicated that reference equations can be obtained for MDS and ψstem by pooling data across several seasons using crop reference evapotranspiration (ETo), daily mean vapor pressure deficit (VPDm) and mean daily air temperature (T
m) in the case of MDS, and ETo in the case of ψstem. The best predictor of MDS under non-limiting soil water conditions was T
m, suggesting that MDS reference values can be obtained by means of easy and cheap measurements. MDS and ψstem values were not influenced significantly by yield or crop load variations between years. A negative linear relationship between
MDS and ψstem was found, pointing to an unchanging radial hydraulic conductivity in the bark tissues and suggesting that the MDS is controlled
by water potential. 相似文献
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Luis Figueredo Adriana Villa-Murillo Yelitza Colmenarez Carlos Vsquez 《Journal of insect science (Online)》2021,21(2)
Sugarcane spittlebugs are considered important pests in sugarcane crops ranging from the southeastern United States to northern Argentina. To evaluate the effects of climate variables on adult populations of Aeneolamia varia (Fabricius) (Hemiptera: Cercopidae), a 3-yr monitoring study was carried out in sugarcane fields at week-long intervals during the rainy season (May to November 2005–2007). The resulting data were analyzed using the univariate Forest-Genetic method. The best predictive model explained 75.8% variability in physiological damage threshold. It predicted that the main climatic factors influencing the adult population would be, in order of importance, evaporation; evapotranspiration by 0.5; evapotranspiration, cloudiness at 2:00 p.m.; average sunshine and relative humidity at 8:00 a.m. The optimization of the predictive model established that the lower and upper limits of the climatic variables produced a threshold in the population development rate of 184 to 267 adult insects under the agroecological conditions of the study area. These results provide a new perspective on decision-making in the preventive management of A. varia adults in sugarcane crops. 相似文献
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