Growth in Nursery and Plant Quality of Selected Trees of Pinus cembroides Zucc

Objective: The objective of this research was to evaluate the growth and quality of Pinus cembroides seedlings. Theoretical Framework: The growth and quality of Pinus cembroides seedlings depend on various biotic and abiotic factors that must be considered for their management in the nursery and their subsequent establishment in the field. The successful establishment of P. cembroides in reforestation and ecological restoration programs depends on the production of high-quality seedlings. Method: The seeds from 12 trees were selected for their productive capacity and were planted in plastic tubes with a volume of 125 ml. The number and length of cotyledons and the diameter of the hypocotyl were measured for the seedlings. The diameter and height of the saplings were measured monthly. For plant quality, nine saplings from each tree were selected, and their root and aerial parts were separated. Both parts were weighed and then dried in an oven to obtain their biomass. The Dickson Quality Index (DQI), slenderness index (SI), lignification index (LI), and the dry biomass ratio of the aerial part to the dry biomass of the root (BSA/BSR) were calculated. Results and Discussion: The statistical analysis showed a significant difference (p≤0.05) between trees for the quantified variables and indices, except for the number of cotyledons and the lignification index. The longest cotyledons were found in family 73 with 3.5 cm, the largest diameter was observed in the seedlings of trees 22, 24, 36, 73, and 346 with 4.4 mm, while the tallest trees were 20, 24, 36, 225, and 350 with 28.6 cm. Regarding the Dickson index, the highest average was found in families 26, 36, 73, 74, and 346 with 0.48; for the slenderness index, families 225 and 350 had an average of 7.8; for the lignification index, families 20, 74, 149, and 346 had an average of 0.41; and for the biometric proportionality index, tree 225 had a value of 4.3. Research Implications: This research contributes to expanding knowledge about the biology and ecology of Pinus cembroides, as well as the best practices for its production and establishment in the field. This can serve as a foundation for future research in the forestry and agroecological fields. Originality/Value: This study contributes to the generation of knowledge applicable to reforestation and ecological restoration programs, proposing nursery management strategies that optimize the production of high-quality seedlings. This is key to increasing survival rates in the field and improving the success of forestry projects in arid and semi-arid areas.