Provenance variability in cone, seed and wing characteristics of Aleppo pine (Pinus halepensis Mill.) from Djelfa, Algeria

Aleppo pine is one of the most important coniferous trees in the Algerian natural forests, where it plays a major role in the rehabilitation of degraded soils and provides a valuable renewable raw material for local populations. However, during the last decades Aleppo pine forests have known an alarming regression in Algeria due to anthropogenic pressure, wildfires and climate changes. Under these conditions there is urgently needed to locate better seed provenances for future reforestation projects. Several works have been conducted to assess the influence of provenance on the biometric features of cones and seeds in Pinus halepensis Mill. However, the influence of provenance on these morphometric traits in Algerian Aleppo pine, particularly in arid zones, remains poorly understood. This study aims to study the variability of biometric characteristics of cones, seeds and wings of P. halepensis growing in four separate provenances in Djelfa province, Algeria. From each provenance ten elite trees were randomly selected, and one hundred ripe cones (n = 100) were collected for biometric measurements. Results indicated that cone and seed traits of the four provenances were significantly different (P < 0.001). Mean values of cone weight (CW), cone length (LC), 1000-seed weight (1000 SW), and seed length (SL) were higher in Senalba Chergui forest, while the average value of cone diameter (CD) was higher in Senalba Gharbi. No significant variation (P > 0.05) was observed among different provenances for seed width (SW). Using principal component analysis (PCA), seed traits (SL, SW, WL, WW, and 1000 SW) were the most important characters in the first principal component (PC1), however cone traits (CL, and CW) were the more important morphometric parameters in the second principal component (PC2). PCA reveals that seed traits are more important for evaluating provenance performance than cone traits. This paper provides results will fill the gap in Aleppo pine genetic resource usage and present guidelines for future breeding programms in area of Algeria. The existence of these variabilities on cones and seeds among Aleppo pine provenances provides further issues to study whether there are related with seed germination to choice the best provenance for artificial regeneration purposes.