ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

The background skin colour of exported mango fruit in relation to tree nitrogen status.

McKenzie, C. B.;

Yearbook - South African Mango Growers' Association Year: 1994 Vol: 14 Pages: 26-28 Ref: 6 ref.

1994

บทคัดย่อ

ABSTRACT :

Mango fruit colour and postharvest keeping quality are critical in maintaining and expanding South Africa's export market share. Market agents can no longer deal with fruits that will not de-green. There may be many reasons for poorly coloured, low quality fruits, but nutritional status of the tree and fruit probably plays a major role. Fruits arriving on the European markets were sampled during the 1992/93 and 1993/94 seasons for quality inspections. Background skin colour was classified and rated. The ratings showed that some growers consistently produced desirable yellow fruits while others produced fruits that would not de-green. A third group fell between the 2 extremes. In addition, development of colour was most closely related to cultivar. Cultivars such as Tommy Atkins and Heidi adequately de-greened, while Keitt and Kent generally did not. A survey of grower nutritional practices showed that orchards with a higher N-status tended to produce green fruits, and those with lower N-status u

sually resulted in the production of yellow fruits. Many growers also cited picking time with respect to fruit maturity as an important factor. N leaf norms are traditionally based on yield with little or no regard to colour and quality, particularly in view of early picking and extended cold transit. Adjustments to these norms, as well as to the timing and type of N fertilization are recommended.