Productivity and quality of seeds of the Siberian stone pine on forest seed orchards in the Republic of Altai

Abstract

The results of a study of seed productivity and sowing qualities of seeds on forest seed objects of the Siberian stone pine (Pinus sibirica Du Tour) in the Pyzhinsky Forestry Compartment of the Turochaksky Forestry District of the Republic of Altai are discussed in the article. The objects of the studies were forest seed orchards of the first order and permanent forest seed plots of improved origin, created in 1980–1988 by seedlings of a plus trees on the area of 22.8 hectares. Evaluation of seed productivity and seed quality was carried out in the average-yield’s year by standard methods. The average seed yield was 31 kg/ha, varying by objects from 8 to 73, the size of the cones was 7.0 × 5.4 cm, varying from 4.5 × 4.0 to 9.0 × 6.0 cm. The main contribution to the variability of yield indicators is determined by the age, which at the time of the studies was 27–34 years. So far, the yield of seeds from cones and the viability of seeds are reduced somewhat in comparison with natural stands. The highest yield (73 kg/ha) and viability of seeds (87 %) is in the most mature forest seed orchard. Based on the dependence of the yield on age, a forecast was made that the forest seed orchard will achieve the natural Siberian stone pine forests of Altai’s seed productivity (150 kg/ha) to the age of 50. The least variable traits are the sizes of cones and seeds and their shape indices (variation coefficients are about 9–10 %). Intermediate and rather unstable reproduced on various objects are the coefficients of variation of seed viability (5–58 %). Obviously, this is due to differences in the efficiency of pollination due to different ages of stands. The greatest variability is typical for weight and counting traits – from 30 to 200 % or more.

Keywords

• pinus sibirica du tour
• forest seed orchards of the first order
• permanent forest seed compartments of  improved origin
• yield
• viability of seeds