Evaluaciòn de extractos etanolicos de manzanilla, ajo, llantén, orégano, ruda en el control de moniliopthora roreri a nivel in vitro

Abstract

Cacao (Theobroma cacao L.) is a plant native to America, it belongs to the genus theobroma. Worldwide, annual cocoa production is 4.3 million tons of cocoa beans, of which 74.9% are distributed, concentrated in West Africa, 12.1% in Southeast Asia and 13% in Latin America. The main cocoa producers in Latin America are Brazil, Ecuador, Peru, Colombia, Venezuela, and Trinidad & Tobago. The cocoa sector grew by 10% and exports reached 260 thousand metric tons (87% grain and 13% derived products). In Ecuador, cocoa production is located in 23 of the 24 provinces. The main diseases in Latin America that attack cocoa plantations are: witch's broom (Moniliophthora perniciosa) and moniliasis (Moniliophthora roreri, in Ecuador, the witch's broom affected 60 to 70% of production, and moniliasis caused losses of up to 80% in cocoa plantations. Cacao moniliasis is a disease caused by the fungus (Moniliophthora roreri). Its symptoms begin with the spores of the fungus attack the fruits depending on the age and environmental conditions causing deformations, brown spots covered with a white mycelium, wilting and necrosis of the fruit completely. The main controls for moniliasis that are put into practice are cultural, chemical and biological control. To present a proposal to the problem of the misuse of less polluting fungicides that benefit the environment, the use of botanical extracts is proposed for the control of diseases caused by phytopathogens, which generate secondary metabolites that form action strategies to inhibit fungal attack. The objective set out in this test is: To determine the best ethanolic extract that inhibits the mycelial growth of the M. roreri fungus at the in vitro level. The plants used were: Plantain (Plantago major), Garlic (Allium sativum), Ruda (Ruta graveolens) and Chamomile (Chamaemelum nobile), with the described plants we wanted to show an antifungal response on the M. roreri fungus. The study was carried out in the plant pathology laboratory of the Faculty of Agricultural Sciences belonging to the Technical University of Machala. The first thing that was carried out in the test was the isolation and purification of the M. roreri fungus for 14 days. Then the plants were dried in the oven for 48 hours at 60ºC except for the garlic, the bulbs were used and were crushed. The botanical extracts were macerated for 48 hours and were placed in plastic containers with a capacity of one liter, 40 g of dry extract + 80 ml of alcohol at 96% purity, achieving a 1: 2 (P / V) ratio. 600ml of potato-destroyer-agar (PDA) culture medium was prepared, 24gr of PDA was weighed, and 60 mg of antibiotic (chlorophenicol) is added to the medium, then with the help of a test tube 99ml of PDA was measured and distributed in 6 glass bottles 20 minutes for sterilization. 6 treatments were carried out where the study variable was the radial growth of the fungus. They were divided into T1 (99ml of absolute control PDA); T2 (99ml of PDA + 1cc of 96% alcohol), and the treatments T3, T4, T5yT6 with (99 ml of PDA + 1cc of botanical ethanolic extract) of each plant. Under controlled laboratory conditions, the T6 treatment (Chamomile ethanolic extract) is statistically superior to the rest of the treatments. It is followed in order of effectiveness by T3 (Ruda ethanol extract) and T5 (Garlic ethanol extract), treatments T4 (Plantain ethanol extract) and T2 (control with 1% alcohol) are statistically equal to T1 (control), that is, they did not have an effect on the mycelical growth of the fungus (Moniliophthora roreri). Treatment 1 (control without alcohol) and treatment 2 (control with 1% alcohol) did not present statistical differences, therefore, alcohol did not interfere with the mycelial growth of the fungus.