T(caps)he term ‘centre of origin’ and ‘centre of diversity’ are often used interchangeably. The centre of diversity refers to a geographic area where the plant species exhibits the highest degree of variation whereas the centre of origin of plant species is an area where species appeared first. In the centre of diversity height, a number of cultivated plant species and their wild relatives exist. The primary consideration of identifying a centre of origin is the presence of wild relatives of the species. Thus the centre of origin corresponds to the centre of diversity where species exhibit the largest degree of variation. Darwin believed about the existence of geographic centres of origin of biological species in ‘On the Origin of Species’ in 1859. Based on Darwin’s belief the concept of centres of origin or diversity arose in connection to get breeding material for selection and improvement of cultivated plants. A. de Candolle published his work on geographic regions of origin of the principal cultivated plants; however Candolle’s geographic region comprised large territories or entire continents. In 1926, N.I.Vavilov published his famous work ‘The Centres of Origin of the Cultivated Plants’ explaining about the 8 centres of origin. There may be two centres of origin of a plant species. While modern tools like molecular biology and DNA maker are in practice in designation and evolution of centres of origin and diversity, Vavilov’s findings are still useful in the study of fruits origin and their domestication as well as introduction. The study of centres of origin and diversity is useful in fruit breeding because these centres serve as genes reserves for disease, pest resistance and fruit quality. Vavilov postulated in his law of Homologous series that characters present in one species are also present in other related species. His famous work ‘The centres of origin of cultivated plants’ and Vavilov suggested that crop plants evolved from wild species in the areas where diversity is present in the species. The areas where species exhibit great diversity and origin are called primary centre of origin of those cultivated plant species whereas the area where although species are not originated but considerable diversity is existing is considered secondary centre of origin. Vavilov purposed following eight centres of origin of cultivated plants:
The China Centre of Origin
The centre consists of the mountainous regions of central & western China as well as neighbouring lowlands. This is the primary centre of origin for Pear, Peaches, Apricots, Plum and Orange, Litchi, Cherry, Walnut, Kiwifruit [Actinidia deliciosa (Achev.) C.F.Liang et A.R.Ferguson] and Chinese apple.
Hindustan Centre of Origin
The centre comprises main central India (excluding North West India, Punjab and Pukhtunkhawa province of Pakistan), Burma, Assam, Malaya archipelago, Java, Borneo, Sumatra and Philippines. It is the primary centre of origin for Mango (Mangifera indica L.), Orange (Citrus sinensis (L.) Osb.), Sour limes (Citrus aurantifolia (L.) Swingle), Coconut, Banana, citron (C. medica L.), Tangerin, Tamarind (Tamrindus indica L.), Mangosteen, Pumelo, Wood apple (Feronia elephantum Correa), Bael (Aegle marmelos Correa), Karonda (Carissa carandas L.) and Aonla (Phyllanthus emblica L. Syn. Emblica officinalis Gaertn).
The Central Asia Centre of Origin
This centre is also known as Afghanistan Centre of Origin and includes North-West India, Punjab, Kashmir, North-West Frontier Provinces (Pukhtunkhawa province of Pakistan), Afghanistan, Russia Tajikistan, Uzbekistan and Tian-Shan (a mountain range in central Asia).It is primary centre of origin for Grape, Apple, Almond, Pear, Apricot and Pistachio Nut.
The Asia Minor Centre of Origin
The centre is also known as Near East or Persian Centre of Origin. The centre comprises the interior of Asia Minor (Asian part of Turkey), the whole of Transcaucasia (Georgia, Armenia and Azerbaijan), Iran and Turkmenistan. It is the Primary centre of origin for Fig, Pomegranate, Grape, Almond, Chestnut, Pistachio Nut, Apple, Pyrus spp. and Prunus spp. as well as a secondary centre of origin for Apricot, Cherry and Quince.
The Mediterranean Centre of origin
It includes the borders of the Mediterranean Sea. It is native place of Olive (Olea europaca L.).
The Abyssinian centre of origin
It includes Ethiopia (Abyssinia) and the hill country of Eritrea (African country) and part of Somalia. The centre is the place of origin for many crops including vegetables but none fruit crop is reported to be native of this centre and according to Vavilov (1992) Abyssinia knew practically nothing about growing fruits until the Europeans arrived. It is the primary centre of origin of coffee.
The Central America Centre of Origin
It is also known as Mexican Center of Origin which comprises South Mexico and Central America. The centre is reported to be Primary centre of origin for Papaya (Carica papaya L.), Guava (Psidium guajava L.), Avocado, Cashew (Anacardium occidentale L.), Cacao, Custard Apple (Annona reticulata L.), Cherimoya (Annona cherimola Mill) and Sapota (Sapota achras Mill).
The South America Centre of Origin
The centre comprises high mountainous regions of Peru, Bolivia, Ecuador, Columbia, Brazil, Paraguay and parts of Chile. It is primary centre of origin of Pineapple (Ananas comosus (L.) Merr.), guava (Psidium guajava L.), Cherimoya (Annona cherimola Mill), Cashew nut (Anacardium occidentale L.) and Passion fruit (Passiflora edulis Sims.).