[Identification characters of leaf morphological and venation pattern of Houttuynia cordata with its confused herb Gymnotheca chinensis].

Objective: To study the identification characters of Houttuynia cordata and its confused herb Gymnotheca chinensis and establish an identification method.

Methods: LMVP (leaf morphological-venation pattern for identification Chinese herbs), and QAERM (quantitatively analyze and evaluate reliability for the method of identification Chinese herbs) were applied for the study.

Results: Both venations were brochidodromous-acrodromous and arising from the mid-petiole or the upper section of petiole. The main characteristic of the leaf of Houttuynia cordata: surface with small gray-white stoma protuberances; Ligulate process of stipule-petiole sheath were clear; Primary veins 7 or 5; The innermost pair of primary vein closed up the top of the sinus at blade base or above sinus, and the section of closed vein was straight; Emitted a smell of fish when fresh leaf was kneaded into pieces. The main feature of the leaf of Gymnotheca chinensis: no small gray-white stoma protuberances; Ligulate process of stipule-petiole sheath were not clear; Primary veins 5; The innermost pair of primary vein closed into the sinus at blade base, and the section of closed vein was slightly curve; No smell of fish. With the mentioned key differences, the both plants could be successfully identified from each other. The accuracy of identification results (AC) was 100%, the repeatability of identification results: agreement rate for observation (ARO) was 100% and Kappa value was 1.00.

Conclusion: The established method is simple, rapid, economic and reliable.