Page 13 - Enzymes in Tropical Soils

Enzymes in Tropical Soils 1

Seest thou not that Allah sends down rain from the sky, and leads it through springs in the
earth? Then He causes (plants) to grow, therewith, produce various colors: then it withers;
thou wilt see it grows yellow; then He makes it dry up and crumble away. Trully, in this, is a
Message of remembrance to men of understanding.
(Quran Az-Zumar 39:21)

Chapter I:

INTRODUCTION

1.1 Roles of Soils in Supplying Nutrient Elements
1.2 Supplying Nutrient Elements from Mineral Sources
1.3 Supplying Nutrient Elements from Non-Mineral Sources
1.4 Scope of Enzymes in Tropical Soils

t has been very well documented that plant nutrients are greatly needed for
I
plant growth and production. Various nutrient elements have been reported to
be essential for plants due to three reasons, i.e: (1) they are needed in one or
more plant physiological processes, (2) if deficient, plant growth and
production will be disturbed, and (3) their physiological functions in plants can not
be substituted by the presence of any other elements. Some elements such as N,
P, and K are essential for all plants; some elements such as V and Na are essential
only for several plants, particularly of low-level plant classifications. On the other
hand, some other elements such as Cd, Se, and Cr are not classified as plant
nutrients because they do not satisfy the above characteristics of essential
elements for plants.

Abdul Kadir Salam - 2014