Evolution of crop Plants in agriculture .pptx

B.sc Horticulture

1. Evolution of Crop Plants Presented By: Prof. Md.Mustafa Dept. of Botany , Uni. College of Science , Kakatiya University-Warangal

2. The origin and domestication of crop plants is a fascinating subject that explores the history and science of how humans have transformed wild plants into cultivated crops over thousands of years Crop plants have evolved through natural and artificial selection, as well as genetic factors such as polyploidy, introgression, and mutation. These factors have increased the genetic diversity and variability of crop plants, which are essential for adaptation and improvement . Cultivated plants are not distributed uniformly throughout the world. Some of the of the crop species show greater variability and their wild relatives in certain areas of the world

3. Why study of origin of crops is important? Search for resistance to diseases and pests . Helps in directing efforts towards crop improvement Eg :(* In sugarcane S. Barberi and S. Sinensis are the result of crosses between S . officinarum x S. Sportaneum As a result, nobalization of canes in sugarcane took place. *In wheat A B D genomes have come from three different wild Sp. Namely T. monococcum, T. speltoids & T. squarrosa to give rise to cultivated hexaploid .) Useful in development of new crops U useful in making collections

4. How to determine centres of origin ? I. Based on presence of wild Spp (Decondelle): in the areas of max. diversity . Problems 1. Difficult to establish true wild Spp. 2 . Some crops lack wild Sp. Ex. Vicia faba II. a ) Archeological : fragments of plants deposited b ) Historical : fagments of plants found c ) Linguistic: based on origin (Naming) III. Evidences from Taxonomy IV. Combination of I, II and III

5. Centres of Origin: In 1926, N. I. Vavilov proposed 08 Centres of Origin :(present 11 centers of origin) Nikolai Ivanovich Vavilov (1922-1930) Russian Botanist, Geneticist

6. (OLD WORLD) I.CHINA CENTRE : The largest independent center which includes the mountainous regions of central and western China, and adjacent lowlands. A total of 136 endemic plants are listed, among which are a few known to us as important crops 1. Apricot Peach Soybean Adzuki bean Velvet bean Chinese yam Radish Chinese cabbage Onion Cucumber

7. II. This area has two sub-centers . A. Main Center (Hindustan): Includes Assam and Burma, but not Northwest India, Punjab, Northwest Frontier Provinces Rice Chickpea Pigeon pea Urd bean Mung bean Cowpea Eggplant Mango Tamarind

8. II B. Indo-Malayan Center: Includes Indo-China and the Malaya . Fifty five plants were listed, including : Yam Banana Coconut palm Sugarcane Clove Black pepper Pamelo

9. III . Central Asian Centre:Includes Northwest India (Punjab, Northwest Frontier Provinces and Kashmir), Afghanistan, Tajikistan, Uzbekistan, and western Tian-Shan. This center lists 43 plants including many wheat. Common wheat, T. vulgare Club wheat, T. compactum Shot wheat, T. sphaerocoecum Pea Lentil Horse bean 7. Onion 8.Garlic 9.Grape 10.Apple

10. IV. Near-Eastern Center/Asian minor: Includes interior of Asia Minor (Anatolian peninsula in Asian part of turkey), Iran and the highlands of Turkmenistan . This region lists 83 species including 9 species of wheat . 1. Einkorn wheat, Triticum monococcum (2n = 14) 2 . Durum wheat, Triticum durum (2n = 28) 3 . Poulard wheat, Triticum turgidum (2n = 28 ) 4. Common wheat, Triticum vulgare (2n = 42 ) 5. Oriental wheat, Triticum orientale 6. Persian wheat, Triticum persicum (2n = 28) 7 . Triticum timopheevi (2n = 28) 8 . Triticum macha (2n = 42) 9 . Triticum vavilovianum , branched (2n = 42)

11. V. Mediterranean Center: Includes the borders of the Mediterranean Sea (Greece, Italy, France). :  This region lists 84 plants including olive and many cultivated vegetables and forages . 1. Durum wheat, Triticum durum expansum 2 . Emmer, Triticum dicoccum (one of the centers ) 3. Pea , Pisum sativum (large seeded varieties) 4 . Lupine 5. Black mustard 6 . Olive 7 . Cabbage 8. Lettuce 9 . Asparagus 10 . Celery

12. VI. Abyssinian Center: Includes Abyssinia, Eritrea, Ethiopia and part of Somali.  This center lists 38 species; rich in wheat and barley . 1. Abyssinian hard wheat, Triticum durum abyssinicum 2 . Grain sorghum, Andropogon sorghum 3. Pearl millet, Pennisetum spicatum 4 . Cowpea, Vigna sinensis 5 . Flax, Linum usitatissimum 6 . Sesame, Sesamum indicum (basic center) 7 . Castor bean, Ricinus communis (a center)

13. New World: Includes southern sections of Mexico, Guatemala, Honduras and Costa Rica. VII . South Mexican and Central American Centre : 1. Maize, Zea mays 2 . Common bean, Phaseolus vulgaris 3 . Lima bean, Phaseolus lunatus 4 . Sweetpotato 5 . Pepper, Capsicum annuum, C. frutescens 6 . Papaya, Carica papaya 7 . Guava, Psidium guayava 8 . Cashew , Anacardium occidentale

14. VIII . South American Center: Two sub-centers are found. VIIIA . Peruvian, Ecuadorean, Bolivian Center: Comprised mainly the high mountainous areas of Peru, Bolivia, Ecuador 1 . Andean potato 2 . Pepper 3 . Tomato 4 . Pumpkin 5 . Egyptian cotton 6 . Guava 7 . Tobacco

15. VIII B. Brazilian-Paraguayan Center 1 . Cassava 2 . Groundnut 3 . Rubber 4 . Pineapple 5 . Cashew

16. Centres of Diversity: A. Primary centres of Diversity: Maximum plant diversity with large no. of relative wild species. B. Secondary centres of Diversity: Only maximum plant diversity but no wild relatives.

17. MICROCENTERS (Harlan 1951): are the small areas within the centres of diversity exhibiting tremendous genetic diversity of some crop plants. 1.Small areas within the pco/sco exhibiting tremendous genetic diversity. 2.Crop evolution tends to proceed at a faster rate in such areas 3. Important for plant collection & experimental study of evolution of cultivated species.

18. CONCLUSION: Evolution of crop plants is a process of genetic and phenotypic changes in plants due to natural or artificial selection over many generations. Evolution of crop plants is influenced by three main genetic factors: polyploidy, introgression, and mutation, which increase the genetic diversity and adaptability of plants. Evolution of crop plants has resulted in the development of various crops with desirable traits, such as higher yield, better quality, and increased resistance to pests and diseases, from their wild ancestors. Evolution of crop plants has been shaped by the geographic, climatic, and cultural factors of different regions of the world, where plants were domesticated and diversified. Evolution of crop plants is an ongoing and dynamic process that continues to respond to the changing needs and demands of human society and the environment .