TITLE:
Role of Micronutrient in Rice Cultivation and Management Strategy in Organic Agriculture—A Reappraisal
AUTHORS:
Shaon Kumar Das
KEYWORDS:
Micronutrient, Trace Element, Minor Elements, Deficiency, Plant Growth, Toxicity
JOURNAL NAME:
Agricultural Sciences,
Vol.5 No.9,
July
31,
2014
ABSTRACT:
Micronutrient refers to the relative quantity of a nutrient that is
required for plant growth. It takes part in metabolic activities, enzymatic
process/catalysts etc. Thus these all directly and indirectly help in plant
growth and development. There are 8 essential plant nutrient elements defined
as micronutrients like boron (B), zinc (Zn), manganese (Mn), iron (Fe), copper
(Cu), molybdenum (Mo), chlorine (Cl) and silicon (Si). They constitute in total
less than 1% of the dry weight of most plants. Organic sources like farm yard
manure, compost, vermicompost etc. may contain less quantity of these nutrients
but presence of these help the plant in their growth and development. They also
called trace elements or minor elements. They are required only in small
amounts (5 to 200 ppm, or less than 0.02% dry weight). The visual symptoms may
be caused by more than one nutrient. Deficiency of one nutrient may be related
to an excess quantity of another. Nutrient deficiency symptoms are observed only
after the crop has already suffered an irretrievable loss. When soil supplies
more quantity of nutrient than the plant’s requirement, plant shows toxicity
symptom.