The oldest direct evidence of cassava cultivation comes from a 1,400-year-old Maya site, Joya de Cerén, in El Salvador. By 4,600 BC, manioc (cassava) pollen appears in the Gulf of Mexico lowlands, at the San Andrés archaeological site. Forms of the modern domesticated species can also be found growing in the wild in the south of Brazil. esculenta subspecies flabellifolia, shown to be the progenitor of domesticated cassava, are centered in west-central Brazil, where it was likely first domesticated no more than 10,000 years BP. Taxonomy History ġ7th-century painting by Albert Eckhout in Dutch Brazil MeFT1 expression encourages motivation of sucrose towards the reproductive organs, as shown by experimental overexpression reducing storage root accumulation. MeFT1 expression in leaves seems to not be photoperiodic, while MeFT2 clearly is. Alleles in cassava include MeFT1 and MeFT2. MeFT1 (FT) is a gene producing FT proteins which affect the formation of storage roots in many plants, including this one. Despite high gene synteny, the HiFi genome assembly revealed extensive chromosome rearrangements and abundant intra-genomic and inter-genomic divergent sequences, with significant structural variations mostly related to long terminal repeat retrotransposons. In each tissue, 20–30% of transcripts showed allele-specific expression differences with <2% of direction-shifting. Differentially expressed transcripts of different haplotype origins were enriched for different functionality during tissue development. The genome shows abundant novel gene loci with enriched functionality related to chromatin organization, meristem development, and cell responses. The complete and haplotype-resolved African cassava (TME204) genome was reconstructed and made available using the Hi-C technology. Nutrition, but deficient in the amino acid methionine. In contrast, cassava leaves are a good source of protein for animal and human However, they are poor in protein and other nutrients.
Cassava roots are very rich in starch and contain small amounts of calcium (16 milligrams per 100 grams), phosphorus (27 mg/100 g), and vitamin C (20.6 mg/100 g). The flesh can be chalk-white or yellowish. A woody vascular bundle runs along the root's axis. Commercial cultivars can be 5 to 10 centimetres (2 to 4 in) in diameter at the top, and around 15 to 30 cm (6 to 12 in) long.
The cassava root is long and tapered, with a firm, homogeneous flesh encased in a detachable rind, about 1 millimetre ( 1⁄ 16 inch) thick, rough and brown on the outside. 5.5 Comparison with other major staple foods.Farmers often prefer the bitter varieties because they deter pests, animals, and thieves. The more toxic varieties of cassava have been used in some places as famine food during times of food insecurity. It must be properly prepared before consumption, as improper preparation of cassava can leave enough residual cyanide to cause acute cyanide intoxication, goiters, and even ataxia, partial paralysis, or death. Like other roots and tubers, both bitter and sweet varieties of cassava contain antinutritional factors and toxins, with the bitter varieties containing much larger amounts. Nigeria is the world's largest producer of cassava, while Thailand is the largest exporter of cassava starch.Ĭassava is classified as either sweet or bitter. It is one of the most drought-tolerant crops, capable of growing on marginal soils. Cassava is a major staple food in the developing world, providing a basic diet for over half a billion people. The Brazilian farinha, and the related garri of West Africa, is an edible coarse flour obtained by grating cassava roots, pressing moisture off the obtained grated pulp, and finally drying it (and roasting both in the case of farinha and garri).Ĭassava is the third-largest source of food carbohydrates in the tropics, after rice and maize. Cassava is predominantly consumed in boiled form, but substantial quantities are used to extract cassava starch, called tapioca, which is used for food, animal feed, and industrial purposes. Though it is often called yuca in parts of Spanish America and in the United States, it is not related to yucca, a shrub in the family Asparagaceae. Although a perennial plant, cassava is extensively cultivated as an annual crop in tropical and subtropical regions for its edible starchy tuberous root, a major source of carbohydrates. Manihot esculenta, commonly called cassava ( / k ə ˈ s ɑː v ə/), manioc, or yuca (among numerous regional names), is a woody shrub of the spurge family, Euphorbiaceae, native to South America.
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