Chemical Control
Chemical control is one of the methods that are broadly used because of favorable and quicker effect. Chemicals used to protect plant diseases that caused by fungal pathogens are known as fungicides. Fungicides kill the pathogens by injuring cell membranes, disabling critical enzymes or proteins and interfering with key metabolic process (Mueller, 2006). Contact fungicides do not go deeper and just remain on the surface where it is applied. This type of fungicide need frequent application to protect new growth and to substitute material that has been washed up by irrigation or rain (Mueller, 2006). Systemic fungicides immersed into plant tissues and move throughout the tissues. Every fungicide has a part in protection such as when a fungicide is present on the plant as a protective barrier before the pathogen arrives or begins to develop so that it prevents infection from occurring. Eradication is the ability to stop disease development after symptoms had developed. Very few fungicides have this capability, and growers must not rely on this as a mean of disease control (Mueller, 2006). Then, growers must know the specific mode of action each fungicide has, so that they know how the fungicide works and apply the fungicide in a correct way in order to fight the disease from spreading.
Biological Control
Biological control is the lessening of pest populations by using natural enemies, to help reduce its impact. By using biological control instead of chemical control, this can avoid the pathogens from building resistance towards pesticides (Linker et.at.,2009). Most of the farmers do not like to use biological control because of expensive cost and less knowledge about the application of biological control agents. Other important steps before applying biological control agents, it must be tested first to make sure they will not be pest themselves and will not post a danger to non-target species. Example of well-known bio control agents is Bacillus thuringiensis that are used as bio pesticide. This bacterium produces delta-endotoxin that affects a variety of species from the orders Coleoptera (beetles), Lepidoptera (moths and butterflies), and Diptera (flies and mosquitoes) and this Bt’s toxin are very specific to certain harmful insects. (Neppl,2000)
Cultural Control
Cultural control is one of the methods to suppress pest population. The strategies of cultural controls include the modifying the relationships between a pest population and its natural environment. In easy way, it is about interrupting an insect’s life cycle. The common cultural controls would be tillage, strategic planting dates, or crop rotation. All of these practices that in some way interrupt an insect pest's life cycle (Storey,2014).
Genetic resistance
One of the pest control methods is by using genetic resistance host plant. There are two types of resistance which are vertical and horizontal resistance. Vertical resistance is when a plant variety exhibits a high degree of resistance to a single race or strain of a pathogen (Saldana.2011). Vertical resistance is also known as specific, qualitative, monogenic, and non-durable and this type of resistance hardly exhibits symptoms (Saldana, 2011). It results in the death of the infected cells, restricting the establishment of the pathogen (Saldana, 2011). Horizontal resistance, on the other hand, protects the plant against several strains of a pathogen, although the protection is not complete, it involves more resistance genes than the vertical resistance and this type of horizontal resistance, in contrast, is equivalent to non-specific, quantitative, multigenic, durable, and field resistance, sometimes infection and disease onset is possible, but this type of resistance protects from many virulent races of the pathogen. (Saldana, 2011). One of the widely used genetic resistance crops is Bacillus thuringiensis (Bt) corn that has been genetically modified through the addition of a small amount of genetic material from other organisms through molecular techniques. (Ric Bessin,2004)
Physical control
Physical control refers to methods that physically keep the pest from reaching their host. There are several methods of physical control one that are widely used is traps, the methods is by using yellow sticky traps. They are covered in a substance that attracts insects, but are actually very sticky or poisonous. These traps are commonly used for fruit flies or leafhoppers. (Meyer, 2003).
Temperature control is one of the physical control, the methods is by placing produce inside of cold storage containers lengthens how long the produce lasts while also hindering the growth of insects inside of them. Another method to use is to heat, as it will kill the insect larvae in certain types of produce. An example would be with mangoes, where they are placed into a hot water bath in order to kill any eggs and larvae. (Meyer, 2003).
Another method called barriers is useful for keeping insects out of one‘s plants. This method known as row covers and they are made out of either plastic or polyester. They are made thin and light to allow plants to still absorb sunshine and water from the air.
(Mahr et. al.,1993)
Regulatory control
Regulatory pest management is to prevent the introduction or spread of pests through the application of various pest management techniques such as pest exclusion, detection, eradication, mitigation, and public education. (Jenkins et.aI.,2006).
When developing a regulatory control program, many factors should be considered including population densities, reproduction and mortality rates, age distributions, the pest’s vigor, the potential for growth and spread of the pest given the new environmental conditions. (Jenkins et.al.,2006).
Regulatory pest management programs use several different strategies which may include identification of risk prevention of entry, survey and detection, eradication, retardation of spread, mitigation of losses.
(Jenkins et.al.,2006).
Ficus deltoidea
Taxonomic Classification
Commonly known as Mas cotek. Ficus deltoidea is the kingdom of plant, a division of Magnoliophyta, class of Magnoliopsida, order of Rosales, family of Moraceae, genus of Ficus and species of deltoidea.
Description
Is an evergreen shrub, F.deltoidea can reach a height of two meters, with whitish grey bark. Leaves of F.deltoidea are broadly spoon-shaped to obovate. Above the leaves has bright green colored whereas beneath the leaves has rust-red to olive brown color.
'Mas cotek'
Anti-fungal and Antibacterial Activity of Ficus deltoidea
Ficus species is a rich source of polyphenolic compounds, flavonoids which are responsible for strong antioxidant properties. (Sirisha et. al.,2010).
An antibacterial compound known as lupeol (C30H500) was also isolated from the leaves of F. deltoidea and exhibited toxicity against Staphylococcus aureus, Bacillus subtilis, and Escherichia coli (Bunawan et.al.,2014).
Two bioactive constituents known as vitexin and isovitexin have been isolated, identified, and evaluated to show alpha-glucosidase inhibition. (Bunawan et.al.,2014).
Qualitative Phytochemical Studies of Ficus deltoidea
Studies showed Ficus deltoidea consists high phenolic acid, pholiphenol, tannin, saponin and flavonoids.(Amiera et.al., 2014). Phenolics play a variety of important roles in the plant. Majority of phenolic substances have important effects on defense against herbivores and pathogens. Many simple phenolic compounds have important roles in plants as defenses against insects, herbivores and fungi. (Ozeker, 1999)
Rhizoctonia solani
Rhizoctonia solani forms colonies on potato dextrose agar (FDA) that range in colour from buff to black and do not produce asexual spores but grow by producing thin, vegetative strands called hyphae. This fungal pathogen will cause sheath blight disease in host like paddy (Naipictuasdharwad,2009)
The symptoms can be seen when the hosts were infected by this fungal pathogen and appear as one or more relatively large, oblong or irregularly elongated lesions on the leaf sheath in advanced stages while the center of the lesion becomes bleached with an irregular purple brown border. Initially these lesions are white in colour, later they turn to dark brown at severe condition (drying of leaves). (Naipictuasdharwad,2009)
Symptoms shows by paddy leaves. Grey spots are formed, as the spots enlarge the centre becomes grayish white. Lesion on the upper parts of plants extend rapidly coalescing with each other to cover entire tillers from the water line to the flag leaf.
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