Journal of Nature Studies 10 (2): 96-107 ISSN: 1655-3179 A COMPARATIVE STUDY ON THE ANTIFUNGAL EFFECTS OF TAMARIND (Tamarindus indica) AND GARLIC (Allium sativum) EXTRACTS ON BANANA ANTHRACNOSE. LEA C. GARCIA University of the Philippines Rural High School Bay, Laguna ABSTRACT This study was conducted to investigate and compare the antifungal activity of tamarind and garlic extracts against anthracnose in bananas. Using the 100mg:1L ratio, extracts of the plants were prepared as T1 – tamarind and T2 – garlic while T3 – commercial pesticide, and T0- no treatment served as the controls. After inoculation with Colletotrichum sp. spores, five (5) banana samples were dipped in all the treatments and were observed for nine (9) days. Statistics revealed that VQR, Firmness, DDI, degree of shriveling, aroma, off-odor, incidence of disease, marketability, color index, off-flavor, sweetness are significantly different. T2 was found to be the best treatment, even better than T3 and much better than T1. For the peel quality and pulp quality ratings, T2 was comparable to T3 in terms of off-odor and color index, while the rest of the parameters showed that T2 was still the best treatment. After the nine days of treatment, the anthracnose which started to develop on the third day was least in T2 next in T3 and T1 while T0 showed the highest incidence of the disease. Generally, for all the tests used, the samples treated with T2 were the best, followed by T3 and T1. Likewise, T2 had the best quality banana samples. Based on these results, it can be concluded that the treatment with garlic (T2) is better than the treatment with tamarind (T1) in preventing anthracnose in bananas. Moreover, T2 was found to be comparable or even better than the commercial fungicide (T3). In terms of cost and a negative effect on the environment, these plant extracts may be used by farmers as substitute to commercial fungicides in the natural prevention of the postharvest diseases of bananas. However, it is recommended that a study on the specific concentrations of garlic and tamarind which are best for treating the disease be made as well as considering naturally occurring diseases of bananas. Keywords: antifungal activity, anthracnose, postharvest disease, parameters INTRODUCTION bananas can be roasted, fried or boiled, and are made into fritters, preserves and marmalades. Its Being rich in natural resources, the extract is used in the manufacture of catsup, Philippines has fertile and arable lands, diverse vinegar, and wine. The unripe fruit is powdered flora and fauna, extensive coastlines, and rich and chipped. Due to the high demand for export, mineral deposits. The country’s primary source of the government and other agencies are working livelihood is its fertile land characterized with together to sustain the production of this important rich, wide plains suitable for farming particularly crop. in the Cagayan Valley, Central Luzon, South Banana production contributes western Bicol, Panay, Negros, Davao, Cotabato, significantly to the national income in terms of Agusan and Bukidnon. The country‘s six major volume of production and export earnings crops are rice, corn, (Calderon & Rola, 2003). The earnings depend on sugarcane, coconut, abaca and tobacco. Except for the quality of the bananas being exported. The rice and corn, all these products are exported, quality of the bananas is determined by size along with bananas and pineapples. (length of fingers and thickness), evenness of As a tropical country, the Philippines ripening, absence of blemishes and defects and the grows an abundant variety of fruit crops primarily arrangement of the clusters. However, the quality for local consumption and export market. Banana of the banana to be exported might be affected due is considered as the most important fruit crop in to several postharvest diseases such as crown-rot the country. Eaten raw, either alone or cut in slices and anthracnose (Colletotrichum musae) (De with sugar and cream, or wine and orange juice, Bellaire and Mourichon, 1997). To cite this paper: Garcia, L. 2011. A comparative study on the antifungal effects of tamarind 96 (Tamarindus indica) and garlic (Allium sativum) extracts on banana anthracnose. Journal of Nature Studies. 10 (2): 96-107 Garcia Characteristics of Banana - The Host part darkens as it ages. The disease can also produce cankers on petioles and on stems that Bananas are herbaceous plants native to causes severe defoliation and rotting of fruits and tropical Southeast Asia. Banana plants produce roots. Infected fruit has small, water-soaked, the seedless banana fruit, valued worldwide for its sunken, circular spots that may increase in size up sweet taste, sticky texture and high vitamin to 1.2 cm in diameter. As it ages, the center of an content. Despite their tree-like appearance, banana older spot becomes blackish and emits gelatinous plants are scientifically classified as herbs. pink spore masses. belonging to Order Zingiberales, or flowering On green banana fruit, the peel has dark- plants,Family Musaceae and Genus Musa brown to black diamond-shaped lesions about 8 x (Wishhart,2010). 3 cm in size. The lesions are sunken with pale The pseudostem is the main or upright margins. Orange fungal fruiting bodies are found growth of the plant, which for some species can growing on the lesions. On yellowing fruit, brown obtain a height of up to 2–8 m, with leaves of up spots initially appear that later become sunken and to 3.5 m in length. Its fruit grows in hanging covered with orange spore masses. A tip rot may clusters, with up to 20 fruit to a tier (called develop and can rot the entire fruit but the pulp is a hand), and 3-20 tiers to a bunch, and averages usually not affected unless the fruit is 125 g, of which approximately 75% is water and overripe. (OISAT,2010). 25% dry matter content. Each individual fruit or To prevent the disease which is banana or 'finger' has a protective outer layer (a uncontrollable and hard to manage, farmers use peel or skin) with a fleshy edible inner portion. the hot water treatment which is done within 24 Typically the fruit has numerous strings which run hours of harvest by dipping the fruit for 5 minutes 0 between the skin and the edible portion of the at 52 C. However, lowering the temperature of the banana, and which are commonly removed hot water will reduce the effectivity of the individually after the skin is removed. Bananas are treatment. Moreover, the treatment needs more a valuable source of Vitamin A, Vitamin time and manpower. On the other hand, use of B6, Vitamin C, and potassium. agrochemicals and pesticides and intensive production methods in plantations poses damage Characteristics of Anthracnose – The Pathogen to the environment. Hence, the study utilized two plants, tamarind and garlic for their antifungal The serious problems that decrease the properties without harming the environment. quality of export bananas (Musa AAA Cavendish) Nelson (2008) reported that these are wound anthracnose and early ripening of fruit pathogens are found wherever bananas are grown caused by the fungus Colletotrichum musae (De but are more prevalent in high-rainfall areas, and Bellaire & Mourichon, 1997; Chillet, 2006). especially where growers do not follow good field Anthracnose spreads from the floral parts and and packinghouse sanitation practices. He also senescent bracts to contaminate fruit in said that premature ripening of affected fruits may plantations. The spores that reach the fruit surface occur after infection. The following are general in runoff rainwater on the banana bunch quickly conditions favoring postharvest banana disease germinate and form melanized appressoria. As symptom development: quiescent structures of the pathogen, appressoria germinate during fruit maturation and form • Poor disease management and cultural infection hyphae colonizing the peel and then practices in banana fields for fungal penetrating into the fruit pulp. When wounded, diseases of leaves and fruits (no de- rot in the fruit develops long before the fruit trashing, poor weed control, mats not ripens, and lesions expand quickly. Anthracnose regularly pruned to thin out plant can trigger early fruit ripening, sometimes population density, and poor soil fertility seriously damaging fruit when it develops during management). container transport. Anthracnose disease attacks all plant • High rainfall and high relative humidity. parts at any growth stage. The symptoms are most visible on leaves and ripe fruits. At first, • Poor sanitation in banana fruit anthracnose generally appears on leaves as small packinghouses (facilities not kept clean and and irregular yellow, brown, dark-brown, or black orderly). spots. The spots can expand and merge to cover the whole affected area. The color of the infected 97 Journal of Nature Studies 10 (2) A comparative study on the antifungal effects of tamarind (Tamarindus indica) and garlic (Allium sativum) extracts on banana anthracnose • Poor fruit packinghouse practices (bananas from a single, central trunk as the tree matures and not washed and dried, dirty de-handing is often pruned to optimize tree density and ease knives, dull knives or ragged cuts during of fruit harvest. At night, the leaflets close up. It de-handing of banana hands from stalks). has red and yellow elongated flowers which are 2.5 cm wide (one inch) five-petalled borne in • Not enclosing banana bunches on plants in small racemes, yellow with orange or red fields with perforated polyethylene sleeves. streaks. Buds are pink as the sepals and are lost when the flower blooms. The fruit, sometimes • Fruits are not refrigerated after harvest and called a pod, 12 to 15 cm (3 to 6 inches) in length before ripening (56°F after packing and with a hard, brown shell, has a fleshy, during shipping is appropriate). juicy, acidulous pulp. It is mature when the flesh is coloured brown or reddish-brown.