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Fig. 1. The functional relations of each term of Eq. [1] for three crops: cotton, 
wheat, and maize. Cotton treatments were thinned (<NT), not thinned (NT), a growth 
regulator, mepiquat chloride, applied once (MC), and twice ( MC2) during the growing 
season. (Data correspond to the equations of Table 4, Wiegand and Richardson, 
1990b).