ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

The effect of calcium and potassium foliar and fruit sprays on Sensation mango leaf nutrient concentrations and fruit quality.

McKenzie, C. B.

Yearbook - South African Mango Growers' Association Year: 1995 Vol: 15 Pages: 44-47 Ref: 9 ref.

1995

บทคัดย่อ

Low leaf Ca and K concentrations have been implicated in export fruit colour and quality problems in mango, despite adequate soil applications and soil levels of these nutrients. Foliar and fruit sprays are used commercially in an attempt to raise concentrations to the desired norms and thereby reduce these problems. Three postharvest sprays on the newly hardened flush and a further 3 pre-harvest (fruit and foliage) sprays were tested using 2 levels each of potassium nitrate, potassium sulfate, calcium nitrate (all at 1 or 2%) and Wuxal Suspension Calcium(R) (at 0.3 or 0.6%). Ca sprays had no beneficial effect on Ca leaf concentrations or fruit quality. Ca(NO3)2 sprays elevated N leaf concentrations with a corresponding increase in mesocarp breakdown. Some measurable uptake of K occurred after 6 sprays of either K fertilizer, indicating that this is a useful but limited method of increasing K leaf concentrations. When individual plot leaf concentrations were compared with fruit quality, Ca and K

 were shown to have little effect. However, with increasing leaf N concentration, ripe background yellow skin colour decreased and jelly seed incidence increased. It was concluded that growers who wish to improve fruit quality should concentrate more on reducing high N concentrations than attempting to elevate Ca and K concentrations via foliar and fruit sprays.