Skip to main content

CENTERS OF ORIGIN



The center of origin (for class 9 to 12)
The concept of centers of origin was first proposed by the Russian scientist Nikolai Vavilov(1887-1943).One of his mission was to collect plant related germplasm for National Plant Breeding Projects. During his exploration Vavilov found that plant diversity tends to concentrate around specific regions .He proposed that these concentration of high variability indicated  the regions where the domestication of crops began .Vavilov identified eight primary centers of origin and plant diversity. Following are the eight centers.
a.      China
b.      India/ indo china
c.       Central Asia
d.      Near East
e.      Coast of the Mediterranean Sea
f.        Ethiopia
g.      South Mexico and Middle America
h.      South America
The study  of centers of origin and diversity is helpful in  plant breeding and genetic research. The genetic variation in this centers serve as rich reserves of genetic material for the improvement of cultivated crops. Genes for disease, pest and stress resistance and nutritional quality are some of the resources that can be found in these reserves. Certain aliens have been scouting across the universe to get different variety of plants which they can introduce in their  planet . Which of the following centers of origin they would visit if they have to get the following crop plants.

1.      Black pepper
2.      Sandal wood
3.      Mango
4.      Jackfruit
5.      Almond
6.      Pear
7.      Pomegranate
8.      apple
9.      Maize
10.  okra
11.  Coffee

12.  Sweet potato
13.  Cocao
14.  Potato
15.  Tomato
16.  Quinine
17.  Rubber tree
18.  Brazil nut
19.  Olive

Comments

Popular posts from this blog

WATER HARVESTING

1. WHAT DO YO CALL THE ABOVE  TRADITIONAL  RAINWATER HARVESTING STRUCTURES IN THE URBAN AREAS OF NORTHERN INDIA ? 2. THE ABOVE TWO IMAGES ARE RAINWATER HARVESTING STRUCTURES IN PATAN , GUJARAT WHICH IS A WORLD HERITAGE SITE . CAN YOU NAME THIS STRUCTURE? 3. THE BELOW IS A PROFILE PICTURE OF A TRADITIONAL RAINWATER HARVESTING STRUCTURE IN THE SEMI ARID REGIONS CALLED KAREZ. CAN YOU TELL ME IN WHICH COUNTRIES YOU WILL FIND THIS WATER HARVESTING STRUCTURE . THIS IS A SERIES OF HORIZONTAL AND VERTICAL WELLS. THIS IS AN EXAMPLE OF APPLICATION OF TRADITIONAL KNOWLEDGE AND SKILL . 4. THIS METHOD OF IRRIGATION IS TRADITIONALLY USED IN TAMILNADU AND ANDHRA PRADESH . DURING ANCIENT TIMES THE CHOLA AND PALLAVA KINGDOMS FARMERS SPEND BETWEEN 6 TO 8% OF THEIR INCOME IN MAINATAINING THIS IRRIGATION SYSTEM . THE KINGS BELIEVED THAT FOOD  SECURITY LEADS TO NATIONAL SECURITY  5. THIS IS A TRADITIONAL METHOD OF RAINWATER HARVESTING SEEN...

CLIMATE ,CL 9

A. B. C. I.WHICH OF THE FOLLOWING CONDITION  IS FAVOURABLE FOR INDONESIA, AUSTRALIA  AS WELL AS PERU. 2. IN THE 19TH CENTURY WHEN CHEMICAL FERTILISERS WERE NOT INVENTED THE GUANO  WERE IN GREAT DEMAND . IT IS  DROPPING OF SEA BIRDS MAINLY CORMORANT . PERU USED TO EXPORT A LOT OF GUANO . CAN YOU GUESS THE REASON WHY PERU USED TO PRODUCE ABUNDANCE OF GUANO. (DOES THE COLD WATER NEAR THE PERUVIAN COAST HAVE ANY ROLE IN THIS). 3.         Maldives and Lakshadweep  support very large population even though they do not produce much of their food requirement especially rice which is the staple diet there. It does not mean that these islands were colonized during recent times, people in very large numbers have inhabited these islands for hundreds of years . Food grain is transported from India and Sri Lanka. This used to be done in the past (even during the times of sailing ships). Dry fish , copra and Jaggery( gu...

biology homework(8)

1. For which agricultural operation the following  machinery are used ? 2. If you are a farmer is this of any use to you ?discuss how? 3. This is an innovation by an Indian farmer can you tell me  in what way this innovation is helpful?   4. YUVRAJ the most expensive cattle in the world . Can you guess why?  5. Name the four oilseeds 6. Can you identify the three beverage crops ? A, B and C from top to bottom? 7.   SEE THE ABOVE THREE PICTURE  AND READ ALL THAT IS WRITTEN INTHE THIRD PICTURE TITLED ALL ABOUT EARTHWORMS YOU WILL BE ABLE TO CONNECT.... A. why is this place where the earthworms are reared covered ? B. This dark coloured soil you find  in the bottom image is considered to be very fertile . How is this soil made fertile ? 8. A. why is the weed problem and chances of disease and pest less in drip irrigation? B. Why is fertilizer use efficiency higher in drip irrigation? C. How water ...