41.
Clubroot of crucifers are favoured by soil pH

42.
Di-ammonium phosphate contains

43.
Witche's broom occurs in

44.
The suitable fertiliser for foliar spray is

45.
Algae often float on surface of water during day but sink down during night due to

46.
Chlorophyll a has

47.
Glyricidia species is used as

48.
A crop plant which can grow in nitrogen deficient soils without external supply of it is

49.
Which of the following herbicides derived from urea?

50.
Which toxin was first isolated in pure form?