General concepts in plant nutrition

General concepts in plant nutrition

The concepts of nutrition and nutrients are often overlooked, merely blended together, or considered as the same or interchangeable idea. Mengel and Kirkby (1982) best described the difference between nutrition and nutrients as nutrition being the "supply and absorption of chemical compounds needed for growth and metabolism" and nutrients as simply being "chemical compounds required by an organism" for whatever undefined reason.

Essential nutrients

All essential nutrients required by higher plants, in this case tomatoes, cucumbers and peppers, are exclusively inorganic in nature. Conversely, animals (including man) and some micro-organisms need, in addition to inorganic nutrients, a supply of organic foodstuffs. This essentially distinguishes animals, including Man, from plants. Plants cannot work with organic nutrients. Therefore, growing plants with purely "organic" nutrients is not only a misnomer but it is also misleading. Higher plants can only absorb and metabolise inorganic nutrients.

 

Only 16 elements, of the 92 natural mineral elements known, are considered essential nutrients for the growth of higher plants:

  • Carbon
  • Hydrogen
  • Oxygen
  • Nitrogen
  • Phosphorus
  • Sulphur
  • Potassium
  • Calcium
  • Magnesium
  • Iron
  • Manganese
  • Copper
  • Zinc
  • Molybdenum
  • Boron
  • Chlorine
  • (Sodium)
  • (Silicon)
  • (Cobalt)

Bracketed elements are considered important, but not essential, for plant growth.

Classification of elements

The classification of nutrient elements into the macro- or micronutrient category is purely arbitrary at best if based solely on the physiological requirements of the plant. For example, often the leaf tissue content of Mn is far in excess of the plant's physiological requirements for Mn . The classification of elements into macro- and micronutrients, based on biochemical concerns, is probably more sensible and appropriate.

 

Living plants consist of 27% organic matter (stems, roots, leaves, flowers and fruit), 70% water and 3% minerals (inorganic ions) (Mengel and Kirkby, 1982). 

Early detection of nutrient deficiencies

Successful culture of greenhouse vegetable crops on Grodan® requires an understanding of plant nutrition. It is beneficial to understand the role(s) of each essential mineral within the plant in order to detect early symptoms of nutrient deficiency. Early detection depends on two key factors:

1. The role of a particular nutrient within a plant

2. Whether or not that element can be translocated from one area of the plant to another.

Our latest blogs

egro, e-gro, grodan, commercial, stills, stil, greenhouse, data layer
By Paulina Florax
e-Gro

On the way to an autonomous greenhouse (part 2)

Data in the greenhouse is growing in importance as a means for optimizing plants. In part 1 of this blog, Head of Chair Group Horticulture and Product Physiology of Wageningen UR Leo Marcelis spoke about the growing use of data and measurements by growers.

Read more
Grodan, e-Gro
By Paulina Florax
e-Gro

On the way to an autonomous greenhouse (part 1)

Optimizing plants is a grower’s daily task. Many growers make frequent use of Wageningen University’s knowledge for it. Professor Leo Marcelis has been researching plants in greenhouse horticulture at Wageningen University in the Netherlands.

Read more
Grodan, e-Gro
By Paulina Florax
e-Gro

From green fingers to data-driven cultivation

In the world of marketing terms such as data mining, AI or machine learning have gained a solid foothold. But their increasing use in horticulture is quite new. Not so strange, since the sector demands new business models in order to realize the transformation from green fingers to data management in the greenhouse. The nice thing is that it’s possible. Let us explain why.

Read more
grodan, nature, water, bigger picture, waterfall
By Stefanie Wienhoven
Water Management

Make better use of your water!

22 March is always World Water Day, a day for increasing awareness of the value of water. In the Netherlands too, the consequences of the extremely dry summer of 2018 are still being felt. As of March 2019, our water supply is still not up to its normal level. The University of Twente recently published an article in Nieuwe Oogst (“New Harvest”, an agricultural news forum) entitled ‘Water here as scarce as in Saudi Arabia’.

Read more
grodan