Camptotheca lowreyana tree named `Katie`

Abstract

A new and distinct cultivar of Camptotheca lowreyana tree named `Katie`, characterized by its freely and vigorously branching; dense and full plant habit; small leaf size; lanceolate to elliptic leaf shape; leaves from both juvenile and mature trees with entire leaf margins; lower temperature and drought tolerance; and high yield of anti-cancer camptothecin in leaves.

Description

BACKGROUND OF THE INVENTIONThe present invention relates to a new and distinct cultivar of Camptotheca, botanically known as Camptotheca lowreyana, and hereinafter referred to by the name `Katie`. The new Camptotheca is named in honor of Mrs. Katie Northrup of Houston, Tex.Camptotheca, also known as Xi Shu or Happytrees, are deciduous trees, native to China, and a member of the Nyssaceae family. Three species of Camptotheca are significant sources of naturally-occurring camptothecins, a very promising anti-cancer chemical substance (Li et al., in press). The anti-tumor activity of Camptotheca was first discovered in 1957 (Wall et al., 1966). Clinical trials of camptothecins in the United States, China, Japan and Europe have shown success in treating may types of cancer (Li and Adair, 1994). Some camptothecin drugs have received approval for cancer treatment in more the 20 countries. Recently, three semi-synthetic drugs from camptothecins (Hycamtin, Campto, and 9-Nitrocamptothecin) w...

AI Technical Summary

Benefits of technology

5. Plants of the new Camptotheca are more tolerant to low temperatures and drought than plants of Camptotheca lowreyana Li and Camptotheca acuminata Decaisne.

6. Plants of the new Camptotheca have a higher yield of camptothecin than plants of Camptotheca lowreyana Li and Camptotheca acuminata Decaisne.

Problems solved by technology

However, the production of Camptotheca trees is limited by low temperatures and drought.