Syllabus
wheat; pulses-chickpea,
pea; oilseeds-rape & mustard, sunflower;
fodder crops- Berseem and
cash crops-sugar cane;
vegetable-potato & tomato and horticultural crops
Cereals
Wheat
Wheat (Triticum spp.) is one of the most important cereal crops worldwide, providing a major source of dietary energy for humans and livestock. Understanding its centers of origin, distribution of species, and wild relatives is crucial for crop improvement and ensuring food security.
Let's explore these aspects of wheat:
1. Centers of Origin:
Wheat is believed to have originated in the "Fertile Crescent," an area in the Middle East that includes parts of present-day Iraq, Iran, Syria, Turkey, and Jordan. This region is considered the primary center of origin for wheat and is rich in wild wheat relatives and diverse wheat species.
2. Distribution of Species:
Wheat belongs to the genus Triticum, which comprises several species with different characteristics and ecological adaptations. The distribution of wheat species can be categorized into three main groups:
- Common Wheat (Triticum aestivum): Common wheat is the most widely cultivated species and includes bread wheat and durum wheat. It is grown in temperate regions worldwide, with significant production in countries like China, India, Russia, the United States, and Canada.
- Emmer Wheat (Triticum dicoccum): Emmer wheat was one of the earliest domesticated wheat species. It is cultivated to a lesser extent compared to common wheat and is mostly grown in some Mediterranean countries and parts of the Middle East.
- Spelt Wheat (Triticum spelta): Spelt wheat is an ancient wheat species with a tougher husk and distinct nutritional properties. It is cultivated in limited quantities in some European countries and North America.
3. Wild Relatives:
Wild relatives of wheat are important genetic resources for crop improvement, as they possess valuable traits such as disease resistance, drought tolerance, and unique genetic diversity. Some of the essential wild wheat species include:
- Wild Emmer Wheat (Triticum dicoccoides): Wild emmer wheat is a wild relative of emmer wheat and common wheat. It is found in the Fertile Crescent and surrounding regions, growing in diverse habitats ranging from mountains to arid regions.
- Aegilops Species: Aegilops species are wild relatives of wheat that are cross-compatible with cultivated wheat species. They are found in various regions, including the Mediterranean, Middle East, Central Asia, and North Africa.
- Wild Einkorn Wheat (Triticum boeoticum): Wild Einkorn wheat is a wild relative of einkorn wheat and is found in the Middle East and some parts of Europe.
- Wild Spelt Wheat (Triticum spelta): Wild spelt wheat is the wild relative of spelt wheat and grows in specific regions of Europe and the Middle East.
The centers of origin of wheat are in the "Fertile Crescent," an area encompassing parts of the Middle East. Wild relatives of wheat, such as wild emmer wheat and Aegilops species, are valuable genetic resources for crop improvement due to their unique traits and genetic diversity.
Pulses
Chickpea
Centers of Origin: Chickpea is believed to have originated in the regions of southeastern Turkey and the Levant (including parts of Syria, Lebanon, Israel, Jordan, and Palestine). These areas are considered the primary centers of origin for chickpeas.
Distribution of Species: Chickpea is a part of the Fabaceae family, and its distribution is primarily divided into two main groups:
- Desi Chickpea: Desi chickpea is predominantly grown in the Indian subcontinent and parts of Southeast Asia. It has smaller, darker seeds and a slightly nutty flavor. India is the leading producer of desi chickpea.
- Kabuli Chickpea: Kabuli chickpea is grown in various countries across the Middle East, North Africa, and parts of Europe. It has larger, lighter-colored seeds and a more delicate taste. Afghanistan is a significant producer of kabuli chickpea.
Wild Relatives: The wild relative of Chickpea is known as Cicer reticulatum. It is found in the eastern Mediterranean region and parts of the Middle East. Wild chickpea species are essential genetic resources for crop improvement, as they possess traits such as disease resistance and tolerance to environmental stresses.
Pea
Centers of Origin: Pea is believed to have originated in the Mediterranean region and parts of Western Asia. The primary centers of origin for pea include present-day countries such as Turkey, Greece, Syria, and Iraq.
Distribution of Species: Pea is a member of the Fabaceae family, and its distribution includes several types:
- Green Pea: Green peas, also known as garden peas, are the most common type of pea consumed worldwide. They are grown in temperate regions and are popular as fresh vegetables and for processing.
- Yellow Pea: Yellow peas are predominantly grown for animal feed and as a source of protein in food products.
- Field Pea: Field peas are used for animal feed, green manure, and sometimes for human consumption in certain regions.
Wild Relatives: The wild relative of Pea is known as Pisum fulvum. It is found in parts of the Middle East and has valuable traits that can be utilized for crop improvement, such as disease resistance and drought tolerance.
Oilseeds
Rapeseed and Mustard
Centers of Origin: Rapeseed & Mustard are believed to have originated in the regions of Central Asia and the Mediterranean. These areas are considered the primary centers of origin for these oilseeds.
Distribution of Species: Rapeseed & Mustard are members of the Brassicaceae family, and their distribution includes various species with distinct characteristics:
- Rapeseed (Brassica napus): Rapeseed is known for its high oil content and is cultivated for both culinary oil and biodiesel production. It is grown in temperate regions, including Europe, Canada, China, and India.
- Mustard (Brassica juncea): Mustard is grown for its seeds, leaves, and oil. It is widely cultivated in countries like India, Canada, China, and Ukraine. Brown mustard, oriental mustard, and yellow mustard are some of the common types of mustard.
Wild Relatives: The wild relatives of Rapeseed & Mustard include various species within the Brassicaceae family, such as Brassica rapa (wild turnip) and Brassica oleracea (wild cabbage). These wild relatives are important genetic resources for crop improvement, as they possess traits such as disease resistance, tolerance to environmental stresses, and unique genetic diversity.
Sunflower
Centers of Origin: Sunflower is believed to have originated in North America, specifically in regions of present-day Mexico and the United States. These areas are considered the primary centers of origin for sunflowers.
Distribution of Species: Sunflower is a member of the Asteraceae family and is primarily classified into two main species:
- Common Sunflower (Helianthus annuus): Common sunflower is the most widely cultivated species and is grown for its edible seeds, oil extraction, and ornamental purposes. It is cultivated in various temperate regions, including Russia, Ukraine, Argentina, the United States, and China.
- Perennial Sunflower (Helianthus tuberosus): Perennial sunflower, also known as Jerusalem artichoke, is grown for its edible tubers. It is cultivated in some regions as a root vegetable.
Wild Relatives: The wild relatives of Sunflowers include various species within the Helianthus genus. These wild relatives are important sources of genetic diversity for crop improvement, as they possess valuable traits such as drought tolerance, disease resistance, and other adaptive characteristics.
Fodder Crop
Berseem (Trifolium alexandrinum)
Centers of Origin: Berseem is believed to have originated in the regions of the Mediterranean and North Africa. These areas are considered the primary centers of origin for this important fodder crop.
Distribution of Species: Berseem is a member of the Fabaceae family and is primarily cultivated for livestock feed. It is a high-yielding leguminous crop with the following characteristics:
- High Yield: It produces abundant biomass, making it an excellent choice for green fodder production.
- Rapid Growth: Berseem has a short growth cycle and can be harvested multiple times within a single growing season.
- Nutritious Fodder: Berseem is rich in protein and essential nutrients, making it a valuable source of feed for cattle, goats, and other livestock.
Wild Relatives: Wild relatives of Berseem, such as Trifolium species, are found in different regions. These wild relatives are important genetic resources for crop improvement, as they may possess valuable traits such as disease resistance, drought tolerance, and higher nutritional content.
Cash Crops
Sugarcane (Saccharum officinarum):
Centers of Origin: Sugarcane is believed to have originated in the regions of Southeast Asia, including present-day countries such as India, China, and Papua New Guinea. These areas are considered the primary centers of origin for this valuable cash crop.
Distribution of Species: Sugarcane is a member of the Poaceae family and is primarily grown for its sugar-rich stems, from which sugar is extracted. It is characterized by the following features:
- High Sugar Content: Sugarcane contains a high concentration of sucrose, making it an essential crop for sugar production.
- Stalk Growth: Sugarcane produces tall, thick stalks that store sugars and provide structural support for the plant.
- Clonal Propagation: Sugarcane is propagated vegetatively by planting stem cuttings, ensuring genetic uniformity in commercial varieties.
Wild Relatives: Wild relatives of Sugarcane, known as Saccharum spontaneum, are found in various regions, including parts of Southeast Asia. These wild relatives are important genetic resources for crop improvement, as they may possess traits such as disease resistance, pest tolerance, and better adaptability to environmental stresses.
Vegetable Crops
Potato (Solanum tuberosum)
Centers of Origin: Potato is believed to have originated in the Andean region of South America, specifically in present-day countries such as Peru and Bolivia. This area is considered the primary center of origin for this important vegetable crop.
Distribution of Species: Potato is a member of the Solanaceae family and is primarily grown for its starchy tubers, which are consumed worldwide. Key characteristics of Potato include:
- Nutritional Value: Potatoes are a good source of carbohydrates, vitamins, and minerals, making them an important dietary staple for many populations.
- Adaptability: Potatoes are grown in diverse climates and soils, making them adaptable to different regions.
- Tuber Formation: The plant forms tubers underground, which serve as storage organs for energy reserves.
Wild Relatives: Wild relatives of Potato, such as Solanum species, are found in South America. These wild relatives are important genetic resources for crop improvement, as they may possess traits such as disease resistance, tolerance to environmental stresses, and unique genetic diversity.
Tomato (Solanum lycopersicum):
Centers of Origin: Tomato is believed to have originated in the regions of Central and South America, including present-day countries like Mexico and Peru. These areas are considered the primary centers of origin for this widely consumed vegetable crop.
Distribution of Species: Tomato is a member of the Solanaceae family and is cultivated for its fleshy, edible fruits. Key characteristics of Tomato include:
- Culinary Uses: Tomatoes are consumed fresh or processed into various products such as sauces, soups, and ketchup.
- Rich in Antioxidants: Tomatoes are a rich source of vitamins (particularly vitamin C) and antioxidants like lycopene.
- Varietal Diversity: There are numerous tomato varieties, including cherry tomatoes, beefsteak tomatoes, and plum tomatoes, each with distinct characteristics.
Wild Relatives: Wild relatives of Tomato, such as Solanum species, are found in South America. These wild relatives are valuable genetic resources for crop improvement, as they may possess traits such as disease resistance, enhanced nutritional content, and better fruit quality.
Horticultural Crops:
Centers of Origin: Horticultural crops encompass a wide range of fruits, vegetables, and ornamental plants, each with its centers of origin in different regions.
Distribution of Species: Horticultural crops are cultivated for various purposes, including fresh consumption, processing, and ornamental purposes. Some common horticultural crops include:
- Fruits: Apples, grapes, oranges, bananas, strawberries, and watermelons are among the most widely cultivated fruits.
- Vegetables: Besides Potato and Tomato, other vegetable crops such as carrots, lettuce, cucumbers, and peppers are extensively grown.
- Ornamental Plants: Flowers and ornamental plants like roses, tulips, lilies, and orchids are cultivated for their aesthetic appeal.
Wild Relatives: Wild relatives of horticultural crops are found in diverse regions and may vary depending on the specific crop. They are essential genetic resources for crop improvement, contributing traits such as disease resistance, unique flower colors, and extended flowering periods.
📚 For comprehensive notes on other chapters of the subject, please visit the website Agricorn - Crop Improvement - II (Rabi Crops).
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