Experimental Tests for Exotic States in the Baryon-Antibaryon System

New experiments are proposed in which negative as well as positive results are significant. A new finite-energy sum rule based on dominance of $\rho$ and $\omega$ exchange for high-energy odd-signature amplitudes gives quantitative estimates for production of doubly charged exotic meson resonances via $\Delta$ exchange in nucleon-antinucleon and pion-nucleon reactions. Absence of exotic resonances with predicted cross sections would indicate serious disagreement with two-component duality.