Q8 of 805 Page 1

In an agricultural field there is a prevalence of the following organisms and crop diseases which are affecting the crop yield badly :

(a) White rust


(b) Leaf and stripe rust


(c) Black rot


(d) Jassids


Recommend the varieties of crops the farmers should grow to get rid of the existing problem and thus improve the crop yield.


Normal varieties of crops are prone to infection by various pathogens which lead to poor growth of crops.To get rid of the existing problems, the farmers should grow improved hybrid varieties as these are mostly resistant to most of the pathogens and give higher yield.



More from this chapter

All 805 →
6

A mature embryo-sac in a flowering plant may possess 7-cells, but 8-nuclei. Explain with the help of a diagram only.

 7

Describe the structure of a nucleosome.

OR


Mention the evolutionary significance of the following organisms :


(a) Shrews


(b) Lobefins


(c) Homo habilis


(d) Homo erectus


 9

How does the application of the fungal genus, Glomus, to the agricultural farm increase the farm output?

 10

Plenty of algal bloom is observed in a pond in your locality.

(a) Write what has caused this bloom and how does it affect the quality of water.


(b) Suggest a preventive measure.