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Chapter 6. Production and Breeding of Lentil

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VIII. Hybridization Methods

A. Hybridization

B. Environmental Conditions

C. Equipment Needed

D. Emasculation of the Female Flower

E. Pollination

F. Other Considerations for Crossing

IX.Genetic Resources

A. Germ Plasm Collections

B. Collection and Utilization of Wild Species

X. Genetics

A. Qualitatively Inherited Traits

B. Quantitative Inheritance

XI. Interspecific Hybridization

XII. Methods Used for Lentil Breeding

A. Pure Line Selection

B. Bulk Population

C. Pedigree Selection

D. Single Seed Descent

E. The Backcross Method

XIII. Breeding Objectives

A. Seed and Straw Yields

B. Diseases

C. Root Rot/Wilt Complex

D. Orobanche

E. Insects

F. Quality

G. Adaption to Mechanical Harvesting

H. Other Objectives

XTV Summary



Since domestication in the Near East, lentil (Lens culinaris Medikus) has held

a prominent place in cropping sequences in semiarid regions of the world and has

provided an important source of dietary protein. Despite the great importance of

the lentil crop to local populations, the crop has often been relegated to marginal

areas where it is grown without the benefit of fertilization, herbicides to control

weeds, pest control chemicals, or irrigation. The crop nevertheless has remained

popular in those areas possibly because of tradition but more importantly because

lentil may be one of only a few crops that can be grown.

Research on improvement of the lentil crop has been minimal until the recent

establishment of the international agricultural research centers and particularly



the establishment of the International Center for Agricultural Research in the

Dry Areas (ICARDA) in 1978 and their mandate for lentil crop improvement.

Landraces of lentil and related wild species have been collected and are being

maintained at ICARDA, at national research centers, and at the US.Department

of Agriculture, Western Regional Plant Introduction Station at Pullman, Washington. The availability of germ plasm has been instrumental in the development of

improved cultivars that have become of increasing importance in the production

of the crop.

Oram and Agcaoili (1994) have pointed out a significant increase of lentil production throughout the world during the 1980s because of yield increases and

increases of area sown. The area sown to lentil has continued to increase in Canada, Turkey, and Australia. The lentil crop, including production practices, germ

plasm constraints to production, breeding, genetics, and uses, is reviewed and



Lentil is one of the principal food crops cultivated in the semiarid regions of

the world, particularly in the Indian subcontinent and in the dry areas of the

Middle East. The crop is a dietary mainstay in those areas and is mostly consumed

by local populations. Of the countries that produce lentil, India is the largest producer followed by Turkey, Canada, and Syria. Ethiopia and Morocco are also

major producers of lentil. Other countries of the Middle East such as Egypt, Jordan, Iraq, and Lebanon are major consumers of lentil but not major producers.

World production in the areas of major use has declined in recent years as a result

of a dramatic shift toward the production of cereals, with legume crops being

relegated to more marginal areas with poorer soils and limited rainfall. Another

major factor in the decline of lentil production in the Middle East, except for

Turkey, has been the high cost of labor for harvesting the crop. In most of

the countries of the Middle East, the crop is harvested almost entirely by hand

(Khayrallah, 1981; Haddad and Arabiat, 1985). Turkey, on the other hand, has

increased its production through partial and, in some areas, complete mechanization. Crop residues from lentil are valuable as livestock feed in many regions

where grazing is limited. In dryland farming systems, the lentil crop offers farmers

an alternative to cereal grains and it contributes to the nitrogen budget of infertile

soil by fixing dinitrogen in symbiosis with Rhizobium.

World production of lentil increased by 72% during the 1980s (Oram and

Agcaoili, 1994), representing an increase of 95 1,000 tons. This dramatic increase

of lentil production resulted from a 4% increase in area sown and an overall increase of 4% in yield per hectare. Production in 1990 was estimated at nearly

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2.3 million tons. Major increases in production have been recorded from Canada

and Turkey. Significant shifts in lentil production have taken place throughout the

last 25 years. For example, the area sown has declined sharply in Syria, Jordan,

Iraq, and Ethiopia.

Production in India, Pakistan, and Bangladesh has remained relatively constant,

even though the crop is harvested almost entirely by hand; however, labor is

readily available in those countries.

Average lentil yields have varied widely from a low of 660 kg ha ' in India to

over 2100 kg ha - I in Egypt (Oram and Agcaoili, 1994) where the crop is grown

under irrigation. Yields have averaged over 1000 and 800 kg ha-' in the United

States and Canada, respectively.

Lentil production has increased to more than 600,000 tons annually in Turkey

(Oram and Agcaoili, 1994) and nearly doubled between 1984 and 1990 (FAO,

1991). Turkey is now the world's largest lentil exporter. The increased production

was brought about by fallow replacement in cereal production systems where sufficient rainfall is received to permit annual cropping (AGikgoz et al. 1994).

Of the lentils produced in the United States, over 85% are exported; however,

there is an aggressive marketing program underway which is designed to increase

domestic usage. Chile and Argentina are also major exporters in the western hemisphere. Canada has recently become a significant producer of lentil, and of the

nearly 230,000 tons produced annually in that country (FAO, 1991), nearly all

are exported. Canada has very quickly become the world's second largest lentil


Lentil has been produced on a commercial basis in the Palouse region of the

United States since 1937 (Youngman, 1968). The Palouse region, located in eastern Washington and northern Idaho and characterized by loess-rolling hills with

elevations of up to 900 m, is the major production area in the United States. In

that region, the crop is most often grown in rotation with cereals where lentil offers

a needed alternative to break cereal disease cycles, provides a crop where grassy

weeds can be adequately controlled, and, through nitrogen fixation, reduces the

demand for nitrogen fertilizers.






Cultivated lentils originated in the Near East arc and Asia Minor (Zohary, 1972;

Williams et al., 1974; Ladizinsky, 1979a, 1993; Zohary and Hopf, 1988). Lens

culinaris ssp. orientalis (Boiss) Handel-Mazzeti, which closely resembles the cul-



Figure 1. Typical habitat of wild L. orienrulis.

tivated species L. culinaris, is widely accepted as the progenitor species. L. culinaris ssp. orientalis has an extended range and can be found throughout the Near

East and as far east as Afganistan. The species is found in rocky and stony habitats

with very little soil (Fig. 1) and in association with other annual legumes, such as

the medics, and annual grasses. The conclusion that the cultivated lentil originated

in the Near East arc from L. culinaris ssp. orientalis is based on discoveries of

carbonized remains of apparent cultivated lentils in the same region over which

L. culinaris ssp. orientalis is distributed. Such carbonized remains have appeared

in early Neolithic settlements that date back to 7000-6000 BC (Helbaek, 1959).

Evidence for the center of origin and domestication of lentil has been reviewed by

Ladizinsky (1979a, 1993).


Cultivated lentil ( L . culinaris) belongs to the genus Lens which is associated

with other genera of the Vicieae tribe (Kupicha, 1981). The Vicieae tribe comprises Lens, Vicia L., Pisum L., Lathyrus L., and Vavilovia A. Fed. Cicer L. had

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