abstract- the evaluation of leaf area and leaf nutritional value is important for crop growth modeling and estimations of its performance. the purpose of this study was to use image processing techniques to develop an economical method to ease the assessment of nutrient status and leaf area (la) of plants and to compare the outcomes of this method with linear models. leaf area and leaf chloroph...

abstract the propose of this study was evaluation of cropsyst model on growth simulation and yield stimation of canola under different irrigation treatments. canola (talaye) was sown under 5 treatment and 4 replicants in completed randomized block designs at the college of agriculture, shiraz universityduring 2007-2008. during the growth season dry mass and lai was meseaured frequently, then mo...

Leaf area index (LAI) is a key structural characteristic of forest ecosystems because of the role of green leaves in controlling many biological and physical processes in plant canopies. Accurate LA1 estimates are required in studies of ecophysiology, atmosphere-ecosystem interactions, and global change. The objective of this paper is to evaluate LA1 values obtained by several research teams us...

BACKGROUND AND AIMS Corner's rule states that thicker twigs bear larger leaves. The exact nature of this relationship and why it should occur has been the subject of numerous studies. It is obvious that thicker twigs should support greater total leaf area ([Formula: see text]) for hydraulical and mechanical reasons. But it is not obvious why mean leaf size ([Formula: see text]) should scale pos...

In this research, to evaluate the effect of superabsorbent polymer and drought stress on the number and leaf area of Lettuce, experimental  research was conducted in a completely randomized design factorial with two treatments of irrigation regime at three levels (60, 80 and 100 percent of crop water requirement) and four superabsorbent hydrogel application (0, 4, 6 and 8 g per kg of soil) in t...