Abstract:

To determine the seasonal changes in the growth and nutrient contents of the female cone for Pinus massoniana Lamb., the growth of the female cone in length and diameter and the nutrient compositions were determined monthly in a 25-30-year-old stand during two successive years at Anhua county, Hunan Province.The results showed that the duration from pollenation to cone mature was about 540 days.The volume and weight of the conelets increased a little during the first year, which were in a bilinear curve model.The growth in dimension and weight of the cones increasded rapidly after April of the second year, which showed a logistic curve model.The seasonal changes in the concentrations of N, P, and K in conelets showed a "V" manner.The concentrations of micronutrients, such as Fe, Zn, and Mn increased gradually from pollenation period to the first winter, while the Cu content remained at a lower level. In the second year of the cone development, all of the contents of mineral elements in cones decreased gradually with the increasing of cone weights.The concentrations of macronutrients in cones from high to low were K>N>P>Ca>Mg and Mn>Fe>Zn>Cu for micromutrients.

Key words: Pinus massoniana Lamb., Development of cone, Element content, Seasonal change