Judul: Resistensi Bibit Jabon Putih dan Merah (Anthocephalus spp.) terhadap Serangan Botryodiplodia theobromae Penyebab Penyakit Mati Pucuk
Abstrak: White and red jabon seedlings are very popular to nurserier, because of the benefits and can improve the economic. The main problem in nurseries are insects and diseases attack. One of the diseases is dieback disease. Dieback disease is caused by B. theobromae, that can make the seedlings death. These pathogens can attack passively and actively. Every plant has a mechanism of resistance to pathogen attack, either structural or biochemical, before and after attacked. This research aimed: (1) to test B. theobromae attacked with non wounded and wounded stem infection methods in jabons; (2) to study the structural and biochemical resistance of jabons to B. theobromae attacked; (3) to study the interaction between the species of jabons and stem infection methods in jabons to the resistance of jabon seedlings; (4) to obtain the most resistance species of jabons to B. theobromae attacked. This research used factorial completely randomized design that combined the species of jabons and stem infection methods in seedling. The structural resistance was done with studying the microscopy of infected and non infected jabon used scanning electron microscope. The biochemical resistance was done with studying the chemical compound of Jabons used phytochemistry analysis. The disease incidency of red jabon seedlings with non wounded stem infection methods were 80%, that were wider than white jabon seedlings were 30%. The disease severity of red jabon seedlings with non wounded stem infection methods were 16%, that were worse than white jabon seedlings were 12%. The response of the species of jabons and non wounded stem infection method for the disease severity showed the same severity. The disease incidency of red and white jabon seedlings with wounded stem infection methods were 100%. The disease severity of white jabon seedlings with wounded stem infection methods were 62%, that were worse than red jabon seedlings were 38%. The response of the species of jabons and wounded stem infection method for the disease incidency showed the same width high, but, the disease severity of white jabon seedlings were worse than red jabon seedlings. The incidency and the severity of disease in jabons with wounded stem infection methods were wider and worse than jabons with non wounded stem infection methods. The white jabon seedlings just had the necrotic resistance as the structural resistance after pathogen attacked. Before and after pathogen attacked of red jabon seedlings, structural resistance were showed with found the structure of trychomaes on the epidermis and the necrotic resistance. The biochemical resistance before pathogen attacked of red jabon seedlings were found secondary metabolites, aspecially, triterpenoid and steroid, but, for white jabon seedlings were just found steroid. After pathogen attacked of red jabon seedlings, the biochemical resistance were showed with found the increase in the content of phenol hydroquinon, tannin and the fixed of flavanoid, but, the white jabon seedlings had the increase in the content of flavanoid, tannin and the decrease of phenol hydroquinon.
Keyword: biochemical resistance, disease incidency, disease severity, stem infection methods, structural resistance