In plant breeding programmes, the entire collection (of plants/seeds) having all the diverse alleles for all genes in a given crop is called
selection of superior recombinants
cross- hybridisation among the selected parents
evaluation and selection of parents
germplasm collection
Which of the following is the best suited method for the production of virus free plants?
embryo culture
meristem culture
ovule culture
anther culture
The process in which mature differentiated cells reverse to meristematic activity to form callus is called
redifferentiation
dedifferentiation
cyto-differentiation
differentiation
Which of the following is an example of a defence used by plants against herbivorous?
I. Production of caffeine, tannin, quinine.
II. More production of non-woody tissues.
III. Production of hairs, thorns, spines.
IV. Production of hormones like chemicals that interfere with insect metamorphosis.
Select the correct codes
I and II
II, III and IV
I, II and III
I, III and IV
Type of blastula in chick is
discoblastula
coeloblastula
amphiblastula
holoblastula
A.
discoblastula
Blastula is an animal embryo at the early stage of development when it is a hollow ball of cells. In chicks, discoblastula is found. It is a modified blastula found in telocithal eggs.
Coeloblastula is a type of blastula found in Coelenterata, lower arthropoda, Echinodermata etc.
Amphiblastula is a poriferan larva.
On the basis of utility, Nagpuri buffaloes are categorized as
milkers
dual purpose
drought cattle
grazers
Which of the following plant is efficient converter of solar energy whose net productivity is 2-4 kg/m2/yr or even higher?
Wheat
Rice
Sugarcane
Bajra