Tag: botany

A.Cotton – Smooth leaved and nectar less cotton varieties do not attract bollworms

B.Sugar cane – Saccharum barberi is crossed with Saccharum officinarum, the newly formed varieity shows the desirable qualities of high yield, thick stems, high sugar and ability to grow.

C.Maize – High aspartic acid, low nitrogen and sugar content in maize leads to resistance to maize stem borers.

D.Wheat – Solid stems lead to non preference by the stem sawfly.

So, the correct answer is ‘Maize’.

Clone is a group of plants produced from a single plant through asexual reproduction or progeny of single plant obtained by asexual reproduction is known as clone.

The mutagenic property of mutagens was first demonstrated in 1927, when Hermann Muller discovered that x-rays can cause genetic mutations in fruit flies, producing phenotypic mutants as well as observable changes to the chromosomes. His collaborator Edgar Altenburg also demonstrated the mutational effect of UV radiation in 1928. 

Gene banks are a type of biorepository which preserve genetic material. For plants, this could be by freezing cuttings from the plant or stocking the seeds (e.g., in a seedbank). For animals, this is the freezing of sperm and eggs in zoological freezers until further need. With corals, fragments are taken which are stored in water tanks under controlled conditions. Plant genetic material in a 'gene bank' is preserved at -196 celsius in liquid nitrogen as mature seed dry. In plants, it is possible to unfreeze the material and propagate it, however, in animals, a living female is required for artificial insemination. While it is often difficult to utilize frozen animal sperm and eggs, there are many examples of it being done successfully. Ex-situ conservation of plant genetic resources can be achieved through different methods such as seed banks, field gene banks, in-vitro storage methods, pollen banks and DNA banks. Thus, the correct answer is option B.

Mutation breeding is the way toward presenting seeds to synthetic concoctions or radiation so as to create freaks with attractive qualities to be reproduced with different cultivars. 

The process of mutation breeding involves inducing mutations artificially through use of chemicals or radiations and selecting plants that have the desirable character as a source in breeding.

Pullorum disease is caused by one of the two poultry-adapted strains of Salmonella bacteria. It causes mortality in birds up to 3 weeks of age. Occasionally, it can cause loss in adult birds but also infects parrots, sparrows and peafowl

In biological control method, birds, insects and other living organisms are deliberately let out in fields to selectively kill pests. This becomes an easy method for protecting crops against selective pests. This is an environment friendly method to control the pests.