PARTITIONING AND RECYCLING OF FALL APPLIED BORON IN COMICE PEARS

This study was carried out on mature Comice pear trees on BA29 quince rootstock.
Labelled B (99.63 Atom % B-10) was applied postharvest as boric acid.
Treatments were: foliar B at 500 ppm; foliar B (500 ppm) plus urea (2.5%), and soil B at the same per tree rate as the foliar treatments (8 g boric acid/tree). Postharvest foliar B was mobile and it was transported out of the leaves into storage tissues for the next year’s growth, but soil applied B remained in the roots and very little was transferred to the above-ground portions of the tree until one month after full bloom.
The storage pool of B partitioned equally among young developing tissues but fruits were very strong sink of reserve B. Boron from the storage pool was diluted during the growing season as roots absorbed new-non labeled B from the soil.
Isotope ratios revealed that regardless of tissues sampled, the addition of urea increased B uptake.
These results showed that it is advantageous to mix both compounds in a postharvest fertilizer program

VII International Symposium on Pear Growing

E. Sánchez, T. Righetti, D. Sugar

Pyrus communis, isotopes, fruit trees, foliar nutrition

https://doi.org/10.17660/ActaHortic.1998.475.41