Potassium nitrate in tomato nutrient management

HIGHER YIELDS AND BETTER QUALITY

Fertilization and foliar applications of potassium nitrate have been found to be beneficial in improving fruit size, dry matter, color and flavor.

STRONGER PLANTS AND HIGHER GRADE FRUITS

_KNO3 has been shown to reduce disease incidence and help with resistance to environmental factors such as frost and drought. Fertilization and foliar applications can result in increased fruit integration.

FASTER ABSORPTION

Nitrate nitrogen and potassium in _KNO3 are immediately available through the roots with fertigation and available through the leaves with foliar application.

Fertilization and foliar applications with potassium nitrate have proven to be very efficient in meeting the potassium requirements of many crops.

The combination of potassium and nitrate has been found to be beneficial in improving fruit size, dry matter, color, flavor, and resistance to biotic and abiotic stresses, for citrus fruits and tomatoes. An experiment was conducted with tomatoes to see the effect of various K sources (_KNO3, KCI and K _SO4) on tomato yield. Potassium nitrate was superior to other K sources in terms of yield and average weight.

The effect of various K sources on tomato dry matter yields

Source: Achilea, O. 1999. Citrus and tornato quality is improved by optimizad K nutrition. Springer Netherlands - Improved Crop Quality by Nutrient Management:19-22.

Potassium nitrate outperformed alternative K sources for tomato processing in terms of yield and quality.

In Hungary, 92 kg ha-1 of extracted _K2Oapplied as potassium nitrate (NOP) was shown to be superior to potassium chloride (MOP) and potassium sulfate (SOP) in terms of total marketable yield (12.8% over control), average fruit weight (3.9% over control) and dry matter content (26.1% over control).

In Spain, potassium nitrate improved plant yield by increasing average plant yield, ºBrix and average fruit weight by 25%, 5.13% and 5.15%, respectively. Total yield increased from 59 to 70 t ha-1.

In Italy, when 70% of this dose was applied as potassium nitrate by fertigation, the treatment resulted in higher yields, a higher proportion of class I fruit and a higher average fruit weight. In Israel, nitrate was found to be the best form of nitrogen for maximum lycopene concentration in fresh fruit.

The effect of different K sources on total tomato yield in Hungary.

Total yield, total plant yield and total lycopene yield (by color) increase (%) by using potassium nitrate in tomato processing.

*Means with the same letter indicate no statistically significant differences * Source: Achilea, O. and U. Kafkafi. 2002. Enhanced performance of processing !ornato by potassium nitrate-based nutrition. VIII International Symposium on the Processing Tomato 613: 81-87.