The most common fruit crop that is grown on the territory of Ukraine (almost 70% of the garden area) is apple. Its fruits can preserve consumer quality characteristics for a long time. Fresh apples contain valuable minerals for the human body, vitamins, easily digestible sugars, organic acids, pectin and aromatic compounds. The biochemical composition of the fruits largely depends on the biological characteristics of the variety, climatic and weather conditions, soils and their maintenance systems. Bitter pit, physiological disease of apples, substantially impairs the quality and hardness of the fruits, which leads to losses.
Bitter pit (subcutaneous spots) is manifested in fruits not yet collected from trees. It is connected, first of all, with lack of calcium. It appears on the fruits in the form of green "depressed" spots. During storage the spots are drilled, the pulp in the place of depression becomes brown, with bitter taste. The development of the disease is facilitated by excessive tree trimming, premature or very late harvesting. The disease is intensely manifested in years with high humidity in the spring-summer period. High temperatures and low relative humidity in the repository also provoke the disease.
In fact bitter pit is not manifested if the content of calcium in the fruit (calculated as oxide) at the end of July - beginning of August is higher than 1.9%.
To control the disease, the soil should be treated with lime to reduce acidity and calcium containing fertilizers should be applied as foliar nutrition during vegetation.
The deficiency of calcium in the fruits, as the studies show, occurs at the beginning of the fruit formation. Maximum uptake of calcium in the apple fruits is observed during six weeks from the end of flowering. The movement of calcium ions in apple tree is very slow, and therefore the first nutrition should be done as soon as possible - immediately after flowering. To achieve a positive effect it is recommended to make 2-4 applications with intervals of 10-14 days.
Which fertilizers are the best for calcium foliar nutrition? – Chelated! There is a lot of information on this topic, and therefore, in our opinion, it is not necessary to conduct additional research on fertilizers in the form of simple salts or organic and mineral complexes. Usage of calcium salts, especially chlorides, can even have negative consequences, especially in hot weather. This fertilizer can cause burns on leaves and fruits, and in the worst case it can lead to severe leaf fall, which negatively affects the crop both current and next year.
Since 2015 ECOORGANIC company offers a special fertilizer ECOLINE Calcium-Boron (Chelate) (N - 2,1%, CaO - 4,2%, B - 0,7%). This complex concentrated micro-fertilizer is designed to eliminate the manifestation of calcium and boron deficiency, as well as for foliar fertilization of the crops, especially demanding for the provision of calcium and boron (sugar beets, sunflower, oilseed rape, vegetable and fruit crops). The fertilizer contains calcium in the form of chelate and boron in the form of organic and mineral complex with monoethanolamine. The product is suitable for tank-mixes with plant protection products, it improves plants’ stress and cold resistance.
ECOLINE Calcium-Boron (Chelate) is recommended for foliar application in cereals, technical, vegetable and fruit crops.
This fertilizer provides:
- regulation of boron nutrition in the critical phases of plant development;
- improvement of root system functioning;
- regulates the flowering process;
- resistance to stress factors;
- increase of plant productivity;
- improving yield quality.
Dose rate and number of applications:
|Crops||Time of application||Dose rate, l/ha||Number of applications|
|Kernel fruits||Beginning of fruit formation||1,0 - 3,0||2 – 4 times with intervals of 7 – 10 days|
The fertilizer is well combined in tank mixtures with most of the crop protection products without reducing their efficiency.