Crop Guide: Nutrients for Pepper

Blossom end rot (BER) 

BER occurs mainly during hot weather conditions. Fruits are affected in their early stages of development (10-15 days after fruit set); the cause is related to the rate of calcium supply to the fruit, which is lower than the rate of the fruit growth. This results in the collapse of certain tissues in the fruit, demonstrated as BER. Factors that favor BER are directly related to limited calcium uptake and transport to the fruit, like high salinity, high temperatures and high growing intensity and water shortage.

 

Black spot or stip is shown in the fruit as grey/black spots, which develop under the skin in the fruit wall about the time the fruit attains a diameter of 8 centimeters or more. As the fruits ripen, the spots slightly enlarge and turn green or yellow. Stip is a calcium disorder, caused by excessive N-NH₄ and K rates. Susceptibility greatly varies by variety.

 

 

Table 5: Visual symptoms exhibited by pepper plants under nutritional disorders.

 

Nutrient	Deficiency symptoms	Excess / Toxicity symptoms
Nitrogen	Plant development gradually slows down. Gradual drying, beginning at leaf margins, of the area between the lower leaf veins. The petioles bend and hang downwards, parallel to the stem. The plant develops few flowers and fruit setting is poor. The fruit receptacle is thin, and the ovary is small. Sometimes there is no fruit development on the plant at all, and on those plants that bear fruits, the fruit is deformed.	Plants are usually dark green in color, have abundant foliage, but usually with a restricted root system. Flowering and seed production can be retarded.
Phosphorus	The plants display limited growth. The leaves are hard and brittle to the touch. Flower formation is defective. Few flowers develop, and in those that do develop, only one in every four or five develops a fruit. The fruit is underdeveloped, with a thin receptacle, and very few seeds. The root system is undeveloped.	No typical primary symptoms. Copper and zinc deficiencies may occur due to excessive phosphorus.
Potassium	Yellow chlorosis spots appear between leaf veins, firstly in the lower leaves. The veins and the areas adjacent to these spots do not change their color. Later, the chlorotic spots become lighter. (This can be seen mainly in the upper parts of the plant). There is little fruit setting, and not much fruit, which is smaller than usual.	Usually not excessively absorbed by plants. Excessive potassium may lead to magnesium, manganese, zinc or iron deficiencies.
Sulfur	Causes leaves to become yellowish.	Reduction in growth and leaf size. Leaf symptoms often absent or poorly defined. Sometimes interveinal yellowing or leaf burning.
Magnesium	Is Common on pepper plants. Yellowing of the leaves is apparent in the interveinal areas and veins remain green. The oldest leaves are affected first. Sometimes magnesium deficiency occurs when excessive applications of potassium have been made. It may also show up under extremely hot dry weather.	Very little information available.
Calcium	The most common reason for Blossom End Rot of the fruit (see figure 7). This may be corrected by foliar spray of calcium chloride or calcium nitrate. Further information following downwards.	No consistent visible symptoms. Usually associated with excessive soil carbonate.
Iron	Symptoms show at the later stages of growth. The young leaves fade and then become yellow in the areas between the veins. The veins remain green.	Rarely evident in natural conditions. Has been observed after foliar iron sprays manifested as necrotic spots.
Chloride	Wilted leaves, which then become chlorotic bronze, and necrotic.  Roots become stunted and thickened near tips.	Burning or firing of leaf tips or margins. Bronzing, yellowing and leaf abscission and sometimes chlorosis. Reduced leaf size and lower growth rate.
Manganese	Chlorotic spots between the upper leaf veins.	Sometimes chlorosis, uneven chlorophyll distribution. Reduction in growth. Lesions and leaf shedding may develop later.
Boron	The deficiency manifests itself very quickly. The lower leaves curl upwards. Growth is stunted. The plant develops a thick, short stem. The apex withers and the leaves become yellow from bottom to top of the plant. See figure 8. There is a reduced production of flowers, and fruit setting is poor.   Boron deficiency; the growing points die and decay, and the leaves are misshapen:     Boron excess:	Yellowing of leaf tip followed by progressive necrosis of the leaf beginning at tip or margins and proceeding toward midrib.  See figure 9.
Zinc	The leaves become narrow and small in chili.	Excessive zinc commonly produces iron chlorosis in plants.
Copper	Appear late in the vegetative stage. The leaf margins curl and dry up. The leaves and the fruit become narrow and rectangular.	Reduced growth followed by symptoms of iron chlorosis, stunting, reduced branching, thickening and abnormal darkening of rootlets.
Molybdenum	The foliage turns yellow-green and growth is somewhat restricted. The deficiency occurs most commonly on acidic substrates.	Rarely observed. Sometimes leaves turn golden yellow.