Grape (Vitis sp.) belonging to Family Vitaceae is a commercially important fruit crop. The grapes fruit contains about 20% sugar in easily digestible form besides being rich in calcium and phosphorus. Also, it is mostly consumed as fresh fruit and dry fruits like raisins, etc.

The Role Of Elements

Grapes is one of the fruit crops that are grown widely in the world and grapes occupy the second rank in terms of production, Egypt is the largest Arab countries producing grapes, and considered one of an important economic and exported crop, which is affected by potassium directly in terms of: -

  • Strong growth of vines and increase its productivity, which reflected on increasing yield.
  • Plays an important role in production and transport of sugars in plant.
  • Helps to reduce sugars and turn them in to starch.
  • Increasing storage ability of clusters and handling.
  • Essential for photosynthesis process.
  • Increases plant resistance to certain diseases.
  • Increase fertility and berries size of in cluster.
  • Increase vines tolerance to soil salinity.

Grape crop was affected by the shortage of phosphorus because phosphorus is one of the Essential nutrients:

  • Stimulates lateral roots and fibrous roots to grow and distribution.
  • Increase percentage of fertile buds and flowering.
  • Increase weight and size of berries and sugar content.
  • Early maturity in fruits.

Calcium is one of the most important nutrients for the productivity and quality of the grape crop because it has many physiological effects, the most important of which are:

  • Resistance to grains and clusters of fungal and bacterial diseases, especially powdery mildew.
  • minimize berry shatter of clusters.
  • enhances root growth and distribution as well as increase root resistance to root rot.
  • Increase strength of vegetative growth and yield.
  • Increased flowering, fertilization, fruit set and berry growth
  • Increased berry hardness and storage ability of clusters and berry.
  • Reduces of berry cracking percentage.

Deficiency Symptoms


Potassium deficiency symptoms on grapes lead to poor vegetative growth and yellowing edges of leaves to inside. Before burning of leaves a dark purple color appears, the most important of these symptoms are:

  • In late cases copper brown spots appear on leaves and leaves size decreases.
  • Continuously shortage of potassium causes dries of leaves and wilted before it time, especially the one in the middle.
  • Reduction in berry size and dryness lower part of cluster.
  • When potassium shortage yield decrease and low quality.
  • Low sugar and coloring in berries.
  • Low storage ability and handling of fruit.


Symptoms deficiency of phosphorus on leaves become a dark green color and under severe deficiency the leaves turn into a scarlet or red color as symptoms of deficiency appear in:

  • Low of fertile fruit buds and thus lack of yield.
  • Deformation of grape cluster and lack of export opportunity.
  • General weakness on plants and low root distributions.


The lack of calcium in grapes leads to the drying of shoot tips of branches and roots as well as:

  • Increases percentage of berry shatter per clusters.
  • Poor hardness and quality of berry and clusters as well as reduced storage ability of fruits.
  • Poor plant resistance to fungal diseases.
  • Increases of berry cracking percentage in the cluster.
  • Dryness of shoot tips of branch and roots.
  • General weakness in growth and distribution of root.