Transcript He made extensive explorations in Eretz (Israel) and neighboring

AARONSOHN, A. (1876-1919);
He made extensive explorations in Eretz (Israel) and neighboring countries and in
1906 and discovered specimens of wild emmer wheat (Triticum dicoccoides) at
Rosh Pinah, a discovery that made him famous among botanists throughout the
world.
he recognized wild emmer as the tetraploid ancestor of durum and bread wheats;
additionally, he claimed that wild emmer, as well as other wild forms of
domesticated plants, may serve as “gene pool" for crop improvement.
The discovery of T. dicoccoides and his articles in European journals gained
scientific recognition and fame for him; in 1909, he went to the USA at the
invitation of the American Ministry of Agriculture; with the support of American
Jews, Aaronsohn founded an agricultural research station in Atlit (Israel), where he
built a rich library, collected geological and botanical samples and inspected crops;
he formulated an agricultural vision for improvement of agricultural varieties and
practices, particularly aimed at dry-land farming.
M.S. Swaminathan :
Born 7 August 1925; Kumbakonam, Tamil Nadu. Ph.D. (1952), University of
Cambridge, U.K.; D.Sc. (h.c.) from 33 Universities.
Research Achievements :
Swaminathan's early researches (1947-60) included the elucidation of the
origin and differentiation of cultivated potato (Solarium tuberosum Linn.),
cytogenetic interrelationships among Triticum spp, induction of mutations
for qualitative and poly genie traits in wheat, methodologies for detecting
and assessing indirect effects or radiations with particular reference to the
nutritional safety of irradiated foods.
His later researches (1960-80) had as their main focus the conservation of
biological diversity with particular reference to rice and wheat, modification
of plant architecture and growth rhythm for raising yield ceilings in wheat
and rice and the development of crop production strategies which can lead
to higher yields per unit by land, water, energy, and time.
Recent researches (1980-93) relate to rice breeding and biotechnology,
impact of climate change on crop productivity and the conservation of
coastal biodiversity with particular reference to mangrove ecosystem.
Plant breeding is the art and science of changing the genetics of plants for the
benefit of mankind. Plant breeding can be accomplished through many
different techniques ranging from simply selecting plants with desirable
characteristics for propagation, to more complex molecular techniques.
Why molecular breeding is important:
Increased quality and yield of the crop
Increased tolerance of environmental pressures (salinity, extreme
temperature, drought)
Resistance to viruses, fungi and bacteria
Increased tolerance to insect pests
Increased tolerance of herbicides
Modern plant breeding
Modern plant breeding uses techniques of molecular biology to select, or in the
case of genetic modification, to insert, desirable traits into plants.
The following are the major activities of plant
breeding;
Creation of variation
Selection
Evaluation
Release
Multiplication
Distribution of the new variety
Marker assisted selection
Sometimes many different genes can influence a desirable trait in plant
breeding. The use of tools such as molecular markers or DNA fingerprinting
can map thousands of genes.
This allows plant breeders to screen large populations of plants for those
that possess the trait of interest. The screening is based on the presence or
absence of a certain gene as determined by laboratory procedures, rather
than on the visual identification of the expressed trait in the plant
Reverse Breeding and Doubled Haploids (DH)
A method for efficiently producing homozygous plants from a heterozygous
starting plant, which has all desirable traits. This starting plant is induced to
produce doubled haploid from haploid cells, and later on creating
homozygous/doubled haploid plants from those cells.
Genetic modification
Genetic modification of plants is achieved by adding a specific gene or genes to a
plant, or by knocking down a gene with RNAi, to produce a desirable phenotype.
The plants resulting from adding a gene are often referred to as transgenic
plants. If for genetic modification genes of the species or of a crossable plant are
used under control of their native promoter, then they are called cisgenic plants.
Genetic modification can produce a plant with the desired trait or traits faster
than classical breeding because the majority of the plant's genome is not
altered.
To genetically modify a plant, a genetic construct must be designed so that the
gene to be added or removed will be expressed by the plant.
To do this, a promoter to drive transcription and a termination sequence to stop
transcription of the new gene, and the gene or genes of interest must be
introduced to the plant.
Transgenic plant
Wheat
Wheat (Triticum spp.)[is a grass, originally from the Fertile Crescent region of
the Near East, but now cultivated worldwide. In 2007 world production of
wheat was 607 million tons, making it the third most-produced cereal after
maize (784 million tons) and rice (651 million tons).
Globally, wheat is the leading source of vegetable protein in human food,
having a higher protein content than either maize (corn) or rice, the other
major cereals. In terms of total production tonnages used for food, it is
currently second to rice as the main human food crop, and ahead of maize,
after allowing for maize's more extensive use in animal feeds.
Major cultivated species of wheat
Common wheat or Bread wheat (T. aestivum) – A hexaploid species that is the
most widely cultivated in the world.
Durum (T. durum) – The only tetraploid form of wheat widely used today, and
the second most widely cultivated wheat.
Einkorn (T. monococcum) – A diploid species with wild and cultivated variants.
Domesticated at the same time as emmer wheat, but never reached the same
importance.
wheat breeding
While wheat breeding programmes worldwide have achieved significant genetic
gains in yield potential without the aid of physiological se-lection tools, breeders,
as well as physiologists, generally agree that future successes will be realized
through a greater integration of disciplinary research.
There are two principal reasons for this. Until the year 2020 at least, demand for
wheat is expected to grow by approximately 1.6 percent/year worldwide and by
2 percent/year in developing countries.
This implies a need to almost double the world average wheat yields in that
period, and albeit steady, recent rates of yield growth, as well as improvement in
genetic yield potential, are too low to keep pace with future demand.
Thus, there is an urgent need to develop new and more efficient wheat breeding
methodologies to complement existing breeding techniques, as well as to identify
new traits, which will drive faster yield gains.
Rice
Rice is the seed of the monocot plant Oryza sativa. As a cereal grain, it is
the most important staple food for a large part of the world's human
population, especially in East and South Asia, the Middle East, Latin
America, and the West Indies. It is the grain with the second-highest
worldwide production, after maize (corn).
The traditional method for cultivating rice is flooding the fields while, or
after, setting the young seedlings. This simple method requires sound
planning and servicing of the water damming and channeling, but reduces
the growth of less robust weed and pest plants that have no submerged
growth state, and deters vermin.
While flooding is not mandatory for the cultivation of rice, all other
methods of irrigation require higher effort in weed and pest control during
growth periods and a different approach for fertilizing the soil.
Rice Breeding
Barley
Barley is a cereal grain derived from the annual grass Hordeum vulgare.
Barley has many uses. It serves as a major animal fodder, as a base malt for
beer and certain distilled beverages, and as a component of various health
foods. It is used in soups and stews, and in barley bread of various cultures,
from Scotland to Africa.
Barley is a widely adaptable crop. It is currently
popular in temperate areas where it is grown as a
summer crop and tropical areas where it is sown as a
winter crop. Its germination time is anywhere from 1
to 3 days. Barley likes to grow under cool conditions
but is not particularly winter hardy.
Barley is more tolerant of soil salinity than wheat, which might explain the
increase of barley cultivation in Mesopotamia from the 2nd millennium BC
onwards. Barley is not as cold tolerant as the winter wheats (Triticum
aestivum), fall rye (Secale cereale) or winter Triticale (× Triticosecale Wittm.
ex A. Camus.), but may be sown as a winter crop in warmer areas of the
world such as Australia.
Barley Breeding
A pea is most commonly the small spherical seed or the seed-pod of the
legume Pisum sativum. Each pod contains several peas. Peapods are
botanically a fruit, since they contain seeds developed from the ovary of a
(pea) flower. However, peas are considered to be a vegetable in cooking.
The name is also used to describe other edible seeds from the Fabaceae such
as the pigeon pea (Cajanus cajan), the cowpea (Vigna unguiculata), and the
seeds from several species of Lathyrus.
P. sativum is an annual plant,
with a life cycle of one year. It is
a cool season crop grown in
many parts of the world;
planting can take place from
winter through to early
summer depending on location.
Mung bean , also known as green bean, mung, mongo, moong, moog (whole) /
mash bean, munggo or monggo, green gram, golden gram, and green soy, is the
seed of Vigna radiata which is native to Bangladesh, India, and Pakistan.
Mung beans are mainly cultivated in India,
China, Thailand, Philippines, Vietnam,
Indonesia, Burma, and Bangladesh, but also
in hot and dry regions of southern Europe
and the southern USA.
Mung beans are tropical (or sub-tropical)
crops, and require warm temperatures
(optimally around 30-35°C). Loamy soil is
best for cultivation.
Brassica is a genus of plants in the mustard family (Brassicaceae). The
members of the genus may be collectively known either as cabbages, or
as mustards. Crops from this genus are sometimes called cole crops,
which is derived from the Latin caulis, meaning stem or cabbage.
This genus is remarkable for containing more important agricultural
and horticultural crops than any other genus. It also includes a number
of weeds, both wild taxa and escapees from cultivation. It includes over
30 wild species and hybrids, and numerous additional cultivars and
hybrids of cultivated origin. Most are annuals or biennials, but some are
small shrubs.
The common oat (Avena sativa) is a species of cereal grain grown for its
seed, which is known by the same name (usually in the plural, unlike other
grains). While oats are suitable for human consumption as oatmeal and
rolled oats, one of the most common uses is as livestock feed.
Oats make up a part of the daily diet of horses, about 20% of daily intake or
smaller, and are regularly fed to cattle as well. Oats are also used in some
brands of dog and chicken feed.
Oat seeds are commonly marketed as cat grass to cat enthusiasts since cats
will readily harvest and eat tender young oat, wheat and some other grass
sprouts