Environmental Factors and Their Relationship with Nitrogen Compounds in Walnut Tree (Carya illinoinensis)

Total Soluble Proteins (TSP) and Total Amino Acids (TAA) help to tolerate adverse conditions in fruit trees. The objective of this research was to determine the influence of temperature and irradiation on the concentration of TSP and TAA in Carya illinoinensis trees. Pearson's correlation and multiple regression were made using mean temperature (°C) and irradiation (MJ·m2) data. The concentration of the TSP related to the temperature and irradiation in root, two correlation models were obtained, one for WN cultivar (F = 3.969, df = 2.9, P > 0.058, R2 = 0.469) and another one for the WA cultivar (F = 1.559, df = 2.9, P > 0.145, R = 0.507) where it was observed that the varieties have the same behavior in root for TSP. However, in the stem, the WA cultivar (R = 7.31, gl = 2.9, P < 0.013, R = 0.788) presented a greater mobility of TSP. In the case of WN cultivar, a lower mobility of TSP was observed (F = 2.407, gl = 2.9, P > 0.145, R = 5.90). In TAA, significant differences were observed in both cultivars: in WN cultivar, the correlation model was observed that at lower temperature and irradiation (F = 12.988, gl = 2.9, P < 0.002, R = 0.862), the concentration of TAA increases. In WA cultivar, it was found (F = 17.481, gl = 2.9, P < 0.01, R = 0.892) that lower temperature and irradiation decrease the concentration of TAA. The concentration of TAA in stem was significant in WN cultivar (F = 6040, df = 2.9, P < 0.022, R = 0.757) but not in WA cultivar (F = 2,602, df = 2.9, P > 0.128, R = 0.605). WN cultivar is the best adapted to climatic conditions in the region, due to its capacity to store an important reserve of nitrogen compounds.