Vanilla is one of orchid family and it stands at the only edible spice in this family. The spice constitutes 0.75% of total importation of spices and according to India Spices Board as quoted by Sasikumar, (2010) “its share is six to seven percent of nearly 1500 million USD of global spice trade.” Few countries produce vanilla for instance, Tonga, Madagascar, and Mexico among others. The vanilla crop produces vanillin whose chemical formula is (C8 H8 O3) and it is processed from the crop’s beans in order to be used to add flavor to a number of manufactured products. However, natural vanilla faces stiff competition from synthetically manufactured vanillin whose raw materials come from alcoholic sulphate wastes, by products of paper industries, and coal tar extracts. In order to increase the production of vanilla crop, this paper looks at the properties of vanilla and ways of its propagation. In addition, the paper further looks at how effective pest control is a main determinant in the global supply of natural vanilla spice.
The history of consumption of vanilla dates back to the era of Lacandon and Manche Chol in which vanilla was used as part of beverages popular with the ruling Itza group. In those olden days, vanilla was consumed as chocolate and anything associated with chocolate was precious given that it had blood symbolism. The noble class therefore treasured it in the entire Mesoamerican cosmogony. Traditional ways were used in the extraction of vanilla and according to Bruman as quoted by Barrera and Fernandez, (2006) “Vanilla also requires a modification process, similar to that of cacao; the fruit of the orchid which originally has green pod must be cured and dried so that it will become a thin, dark-colored pod that produces a characteristic fragrance.” Although the Itza cherished vanilla, they did not grow the crop in big plantations because in order to reduce the danger of pests and diseases in their pieces of land. This is evidence that disease and pest control has been a worry for growing vanilla from decades ago to date.
Propagation of Vanilla Crop
The most common and conventional way of propagating vanilla crop is using cuttings; however for an increased yield, both sexual reproduction and vegetative method of propagation can be used together. “However, a clear understanding of the breeding behavior of the plant is warranted to adopt an appropriate breeding strategy,” (Sasikumar, 2010). There are only three available cultivated species of vanilla like Mexican vanilla, Tahitian vanilla, and West Indies vanilla. India Institute of Spices Research (IIRS) oversees the vanilla germplasm progression and possible improvements. Apart from germplasm in India, there are other germplasm centers in Madagascar and Reunion Islands. However, the center in India is the main research center that gives minimum descriptor and handling procedures for the crop of vanilla.
The breeding behavior of vanilla is characterized by how flowering of the plant forms. Flowering takes place at the axillary inflorescence. Breeding behaviors of the crop originates from Mexico which according to available report, observes major variations in breeding of the V. planifolia. In addition, “India studies are restricted to some observations on pollination time, stigma receptivity, fruit development, etc.,” (Sasikumar, 2010). Different species of vanilla have different pollination behavior with different pollinators. For instance, V. wightiana and V. aphylla set in natural conditions. A number of pollinators like bees, humming bird among other pollinators aid in the pollination of the vanilla. In addition, hand pollination has also been observed in India and Mexico centers (Sasikumar, 2010).
Vanilla beans contain small globose seeds, which disperse through either water or air. It is very difficult for vanilla seeds to germinate in the natural environment (Palama et al., 2010). However, the seeds can germinate in ideal standard condition of humidity, temperature, and nutrition. “In vitro culture of the seeds under tissue culture conditions offer a viable safe option in this regard,” (Sasikumar, 2010). This tissues culture is improved, maintained, and standardized in IISR, India. Other than natural and preconditioned germination, vanilla crop has cultivars through which the crop can grow. Vanilla as has been mentioned earlier vegetative propagation is the conventional way of growing the crop. It is however crucial to observe that original germplasm could vary significantly from secondary cuttings leading to genetic susceptibility. Sasikumar, (2010) observes that despite this difficulty, “Some new variants ‘sub cultivars’ have been recognized in Mexico and Reunion Islands.” Through inter-cultivar hybridization, it is possible to come up with improved vanilla varieties.
In yet another study, Palama et al., (2010) found out that “In vitro germination appeared after three months in culture with highest percentages between the fourth and sixth months.” In the study, it was established that there seem to be early stimulation of a number of metabolic paths including those that mobilize the synthesis of protein among other mobilization processes. At the initial stages of the crop development, there is production of “coumaric acid and glucoside A and B,” (Palama et al., 2010). This entire process is a clear indication that metabolomics process at the initial stage would determine the ability of the crop to produce vanillin.
Diseases Control and Management
Disease and pest management are the most crucial processes that determine output of agricultural products. Vanilla being an uncommon spice, it is in order to analyze the diseases that attack vanilla, and this paper samples the case of vanilla growth in Kerala that stands at 4500 feet above MSL. In the area, vanilla grows in intercropping plantation together with black pepper, coffee, and arecanut among other plants. Diseases were not common in vanilla crops but due to intercropping and crowding of leafy plants, spread of fungal diseases now affect vanilla crop significantly. According to Bhai and Dhanesh, (2008), “All parts of the plant are susceptible to attack by the pathogens,” and that “Species of Phytophthora, Fusarium, Sclerotium, Calospora and Colletotrichum are the commonly occurring pathogens reported to cause serious damages in vanilla.” Fungal diseases are fatal because they can lead to wilting or rotting of an entire plantation.
Diseases affect leaves, stems, roots, and vanilla fruits. Upon identification and pathogenic isolation, a number of findings were deduced. Stem rotting was identified as a serious disease that results to rotting of the entire nodal region. Survey also identified Colletotrichum and Fusarium species as the main pathogens responsible for rotting of the nodal region (Bhai and Dhanesh, 2008). Another deadly disease that is caused by the Fusarium species in root rot. Root rot disease causes drying and rooting of vanilla crop and Bhai and Dhanesh, (2008) note that “The Fusarium species isolated from root and stem rot infection could be identified as F.oxysporun f.sp vanillae.” It is evident from the findings that Fusarium species is the most predominant pathogen in most vanilla plantations. Another fungus, Fusarium oxysporum also poses great threat in vanilla plantations and it affects beans, roots, and crop leaves. The most severe case was reported from Seychelles in the late 19th century due to close plantation of the crop in vine according to Alabouvette et al. as quoted by Bhai and Dhanesh, (2008).
Another finding of the survey established that Rhizoctonia solani pathogen predisposed in roots of vanilla crops and it caused yellowing of stems and root rotting. Nevertheless, a new observation found that vanilla crop had a threat of new disease caused by Colletotrichum species. It causes rotting of the leaf axil and according to Bhai and Dhanesh, (2008), “This may be due to use of Glyricidia as a standard for vanilla which is prone to infection by C. gloesporioides.” C. quinquiseptatum on the other hand causes brown rotting. These new discoveries are crucial in the future growth of vanilla crops because it has not yet been reported in other vine plantations. The discovery of these new fungi also justifies continued research on diseases that affect vanilla crop.
Application of Vanilla Flavor in Manufacturing Sector
Vanilla is among the world’s most popular spices whose application penetrates food and beverages industries, perfume manufacturers, and pharmaceutical sector. As has already been observed in this paper, vanilla crops is limited in supply and with the growing demand of the flavor, its cost continues to rise. Vanilla compound in concentrated in the bean/pods where quantitative extraction of vanillin takes place. According to Sinha et al., (2008) “The active constituents of vanilla are responsible for its various biological and therapeutic activities. The flavor profile of vanilla contains more than 200 components, of which only 26 occur in concentrations greater than 1 mg/kg.” on the other hand, New Africa, (2006) notes that it has more than 250 organic components. Vanilla has a number of bioactive properties according to latest findings necessitated by advances in chemistry and pharmacology. In the food industry, demand for natural vanillin still grows following the discovery of its preservative abilities. The pharmaceutical sector has too constant exploration of “antioxidant, antimicrobial, anticarcinogenic, and antisickling agent,” (Sinha, et al., 2008).
Moulds and yeast cause food spoilage. The different structural formations of moulds and yeast are inhibited by the different structural analogues of vanillin, and as such, vanillin acts as food preservative. “The aldehyde moiety of vanillin has been shown to play a key role in the antifungal activity,” (Sinha, et al., 2008). Pardio, et al., (2010) critical affirm that the preservative property of vanilla by critically studying how it preserves ice cream making nit vital for ice manufacturers. An Antisickling property of vanillin is due to the formation of covalent bond of aldehyde group of vanillin with hemoglobin present in red blood cells. Other than the mentioned significance of vanillin, there are other activities that vanillin helps in; for instance, mosquito repellence and in patch tests and menstruation cycles due to its fragrance (Kwangsukstith and Maibach, 1995). All these properties put vanillin and vanilla flavor among the most popular flavors that exist in natural form. This calls for sustained extraction of vanillin in a way that will minimize the myriad properties of vanillin for the benefit of end users.
Despite the popularity of vanilla flavor, there are economic situations that instead of creating opportunity, will lead to loss of income for growers of the crop. Technological advancements led to synthetic production of vanilla for instance, byproduct of paper industry (Lignin vanillin) had sweater and stronger flavor than that of natural vanilla. In Seychelles, this happens at a time when vanilla production was at its peaks resulting to massive losses. According to New Africa, (2006) “It was consternation and disappointment for planters who almost overnight found themselves faced with an over-stocked market and a falling off in demand where a kilo of vanilla dropped to SR 5.00.” In addition, growing vanilla requires big labor force, which further pushes the price of the precious gift of nature up.
Vanilla is not only used as a flavor in the food industry as earlier thought. Natural vanilla has myriad other significant applications than ever envisaged. This is due to series of scientific researches that continue to grow in its study. Vanilla has both pharmaceutical, medicinal, preservative properties that puts it way above other naturally occurring flavors. The crop remains in high demand due to continued discoveries of its other uses. However, in order to maximize on the production levels and ability of the crop, it is vital to invest in disease and pest eradication at the primary level.