BACKGROUND AND AIMS The deterioration of seasonally tropical dry forests will stop with the implementation of management plans for this ecosystem. To develop these plans, we require information regarding aspects such as germination and the presence of 'empty seeds' of representative species-like, for example, Bursera, a genus with a high number of endemic species of the Mesoamerican Hotspot-tha...

Flavonoids are synthesized by phenylpropanoid pathway. They are known to participate in large number of physiological and biochemical processes in plants. Parthenocarpy and male sterility has earlier been reported by silencing chalcone synthase (CHS) encoding gene. Silencing of CHS has blocked the synthesis of most of useful flavonoids including flavan-3-ols and flavonols. Also, these studies c...

The author wishes to thank Professor Kenneth V. Thimann for reading the manuscript, and for his valuable criticism and suggestions during the progress of the research, which are greatly appreciated. Professor Edward S. Castle's stimulating comments on reading the manuscript are gratefully acknowledged. The author also wishes to thank M\rs. Irmgard Kurland for her help in drawing the illustrations.

Natural and synthetic plant growth regulators have been used with increasing frequency to modify crop plants by changing the rate or pattern, both, of their responses internal external factors that govern development from germination. The use (PGRs) in modern horticulture is well established, particularly industrially advanced countries, application fast picking up developing nations as well. r...