ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Seasonal uptake and utilization of nitrogen by "Sensation" mango trees.

Stassen, P. J. C.; Vuuren, B. P. H. J. van;

Acta Horticulturae Year: 1997 Issue: No. 455 Pages: 351-358 Ref: 5 ref.

1997

บทคัดย่อ

Although annual N applications are required to maintain the N status of mango trees, applications at the wrong time may result in undesirable vegetative growth and physiological problems with the fruits. N uptake and translocation were determined in 2-year-old mango cv. Sensation trees (on Sabre rootstocks), grown in 75-litre pots (buried in trenches) in sand culture, and in 6-year-old trees grown under orchard conditions at Nelspruit, South Africa. The recycling of N from the permanent structures of the tree was also investigated. The maximum peak for N occurred during April, and continued until June. N accumulation in whole trees occurred during the spring. N reserves from permanent structures made a small contribution to growth and fruit development in winter and summer. It is suggested that N should be applied during winter or early spring, postharvest and late in autumn. Six-year-old mango trees producing 52.3 kg fruit/year required 511 g limestone ammonium nitrate (LAN), whereas 18-year-ol

d-trees producing 156 kg fruit/year required 1153 g LAN. It is suggested that calculations of the actual N requirement of mango trees could prove useful for nitrogen fertilizer regimes.