ChileanJAR

The experiment was conducted at La Platina Experimental Station, Santiago, Chile.
Leaves, shoots and roots of 7 years old peaches, cv. Fortuna, were sampled every 30 days between February (post-harvest) and September (full bloom) of 1975. The experimental units consisted in 3 plants with 12 replications.
Chemical analysis were made in one year old shoots and its corresponding leaves, and in roots collected at 20-40 cm soil depth. Roots selected were less than 7.5 mm in diameter. Analized compounds were: total and soluble nitrogen and arginine, expressed in mg/g dry matter.
As leaves reached abscision, both, total and soluble N, decreased, while all nitrogen fractions increased in shoots and roots. This was attributed to hydrolisis and retranslocation from the leaves and a subsequent synthesis in woody tissues.
During dormancy, nitrogen movement in shoots was limited and no variation was detected for any of the analized compounds. On the other hand, an increase, from fall up to June, was observed for both soluble N and arginine in roots. Later on, these fractions tended to stay at its maximun level, until bud swelling.
In shoots, during the full-bloom period, soluble N content was not higher than in August, but total N, as well as arginine, decreased. It is probable that hydrolisis of reserve compounds and synthesis of new ones for new growth are leveled at this time, and that shoots are not getting extra nitrogen from the roots.