Unit 1 -
Crop Improvement – II (Rabi 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 T. aethiopicum T. araraticum T. compactum
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.
FLORAL BIOLOGY
1. Inflorescence of wheat is called Ear or Head. In botanical it is called as spike.
2. The unit is called spikelet.
3. Each floret consist of lemma, palea, androecium and gynoecium.
4. Flowers are bisexual and zygomorphic.
5. Each floret has three stamens with large anthers and a pistil bearing bifid feathery stigma.
6. Wheat stamens are small and produce about 1000-4000 pollen grains per anther.
MAJOR BREEDING OBJECTIVES
1. Breeding for high grain yield.
2. Breeding for good quality with high spikletes.
3. Disease and insect resistance and tolerance to abiotic stresses.
4. Mineral, moisture and heat tolerance.
BREEDING CENTERS: -
International Maize and Wheat improvement Centre (CIMMYT) Mexico. - Directorate of Wheat Research (DWR), Karnal. - All India Coordinated Wheat Improvement Project (AICWIP) Karnal (earlier New Delhi)
BARLEY
Botanical NAME - Hordeum vulgare
FAMILY - Graminacae / Poaceae
CHROMOSOME NO. - 2n = 14
Fertility of the lateral spikelets forms the basis of barley classification and the cultivated barley may be classified into three main groups
i) Six rowed barley (H. vulgare L. emend, Lam)
ii) Two rowed barley (H. distichum, L. emend, Lam)
iii) Irregular barley (H. irregular, E. Aberg and Wiebe)
WILD RELATIVES
Wild Hordeum species are distributed through Europe, Asia, Africa and the Americas.
Secondary centers of diversity of cultivated barley are found in Ethiopia and Morocco and
parts of Asia. H. spontaneum
FLORAL BIOLOGY
1. Inflorescence of barley is called Ear or Head. In botanical it is called as spike.2. The unit is called spikelet.
3. Each floret consist of lemma, palea, androecium and gynoecium.
4. Flowers are bisexual and zygomorphic.
5. Each floret has three stamens with large anthers and a pistil bearing bifid feathery stigma.
6. Barley stamens are small and produce about 1000-4000 pollen grains per anther.
BREEDING OBJECTIVES
i) Yield improvement.ii) Increased adaptability.
iii) Resistance to yellow rust, aphid and nematode.
iv) Improvement in nutritional quality.
v) Improvement in attributes related to malt industry.
IMPROVED VARIETIES / HYBRIDS :
Sr. No. Varieties Features
1 Ratna, Jyoti, Kailas - Hulled varieties
2 Karan-750, Amber, Himadri - Huskless varieties
Kailash, Himani, Dolma, NP-100, - Suitable for hilly areas
Rajkiran - Nematode resistant variety
Nilam and Karan 19 - Better chappati making quality for barley
varieties.
Pulses
Chickpea
B. NAME - Cicer arietnum
FAMILY Leguminoceae
CHROMOSOME NO. 2n=16
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.
The wild species of Cicer closely related to chickpea are :
i) C. bijugum
ii) C. echinospermum
iii) C. ecticulatum
FLORAL BIOLOGY
1. The flowers are papilionaceous.
2. They are solitary in axillary racemes.
3. Double flowers are rare, but are very much sought after by the breeders as possible
sources of yield increase.
4. The calyx has five deep lancelolate teeth. Peduncle and calyx are hairy.
5. Generally, corolla is white.
6. The vexillum is obovate, 8-11 mm long and 7-10 mm wide.
7. Wings are obovate, 8-9 mm long. The keel is 6-8 mm long.
8. Number of pods/plant is highly variable, generally between 30 and 150 depending on the
year, location, sowing time and other factors.
BREEDING OBJECTIVES
(i) Increased seed yield.
(ii) Increased biomass, tall, erect and compact cultivars
(iii) Resistance to diseases
(a) Ascochyta blight.
(b) Fusarium wilt.
(c) Root rot.
(d) Botrytis grey mould
(iv) Resistance to insect pests:
(a) Pod borer.
(v) Tolerance to stress environments:
(a) Cold
(b) Heat
(c) Drought
(d) Saline and alkaline soils.
(vi) Mechanical Harvesting
BREEDING PROCEDURES
1. Pedigree method: for resistance breeding (disease, insect, nematode, orobanche spp)
2. Modified bulk method: for stress situations (drought, cold, heat, iron deficiency)
3. Back cross method: for interspecific hybridization. Limited backcross (one or two) for
desi x kabuli introgression and also for resistance breeding.
IMPROVED VARIETIES / HYBRIDS :
Unit 1 - Crop Improvement – II (Rabi Crops)
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.
BREEDING CENTRE
Directorate of oil seed Research (DOR) Hyderabad.
All India coordinated sunflower improvement project (Bangalore)
