The effect of changes in longitude, latitude and altitude above sea level on Iranian oak seed size

Document Type : Scientific article

Authors

1 PhD Student, Department of Forest Science and Engineering, Faculty of Natural Resources, Urmia University, Iran

2 Associate Professor, Department of Forest Science and Engineering, Faculty of Natural Resources, Urmia University, Iran

3 Assistant Professor, Department of Plant Production and Genetics Engineering, Faculty of Agriculture, Urmia University, Iran

4 Professor, Department of Forest Science and Engineering, Faculty of Natural Resources, Urmia University, Iran

5 PhD of Forestry, Department of Forest Science and Engineering, Faculty of Natural Resources, Urmia University, Iran

Abstract

Background and Objective: Natural regeneration is superior due to the production of higher-quality seedlings, and it is strongly influenced by seed size, which affects seedling growth, establishment, and survival. Seed size represents an important strategy for the competitive ability of forest stands in the environment. Understanding seed size characteristics in the Zagros forests can lead to better management, conservation, and sustainability of these ecosystems. In the Zagros forests, three major oak species are found: Persian oak (Quercus brantii), gall oak (Q. infectoria), and Lebanon oak (Q. libani), among which Persian oak is the most widespread. Given the ecological importance of Persian oak, further research on this species is of high priority. Therefore, identifying the relationship between seed size and geographical latitude, altitude, as well as the trends of seed size variation along these gradients, is essential.
Material and Methods: To this end, seeds were collected from four provenances of Persian oak in the Zagros region (Baneh, Chavar–Ilam, Chekani–Khorramabad, and Sisakht–Yasuj), representing different latitudes and altitudes. In each provenance, 12 trees with similar diameters (30–40 cm) and approximately 100 m apart (to minimize genetic relatedness) were randomly selected along transects. The geographic coordinates of sampled trees were recorded using GPS. About one kilogram of mature acorns was randomly collected from all crown directions of each tree in early December 2022. For 20 seeds per tree, the following traits were measured: seed length, hilum diameter, seed diameter, seed diameter at 8 mm from the tip, length-to-diameter ratio, seed perimeter, perimeter-to-diameter ratio, perimeter-to-length ratio, seed content density, density-to-length ratio, and density-to-diameter ratio. Data normality was tested with the one-sample Kolmogorov–Smirnov test. Morphological traits among provenances and the effects of different factors were analyzed using one-way ANOVA and Duncan’s test (at the 0.05 level). Discriminant function analysis was applied to distinguish among provenances and elevation classes based on seed traits, and functions were tested using Wilks’ Lambda and Chi-square statistics.
Results: Results indicated that with decreasing latitude, seed length and length-to-diameter ratio increased, while diameter, seed content density per length, hilum diameter, and tip diameter decreased. Discriminant function analysis (first and second functions explaining 88% of variance) showed that Baneh had the highest positive distinction (2.956) and Chekani–Khorramabad the strongest negative distinction (–0.998) in the first function. In the second function, Chavar–Ilam showed the highest positive distinction (0.905) while Sisakht had the strongest negative (–0.575). In the third function, Chekani–Khorramabad had the highest positive score (0.781) and Sisakht–Yasuj the strongest negative. Elevation classes also showed significant differences: low elevation (1000–1260 m) had the highest values for seed length, longitudinal perimeter, length-to-diameter ratio, and perimeter-to-diameter ratio. Mid elevation (1260–1540 m) showed the highest values for area, seed content density, longitudinal cross-sectional area, and density-to-length and density-to-diameter ratios. Discriminant function analysis for elevation classes (two functions explaining 85.9% of variance) revealed that mid elevation (1260–1540 m) had the strongest positive performance (0.643) while 1540–1800 m had the strongest negative (–1.259) in the first function. In the second function, mid elevation again had the highest positive (0.561) while high elevation (1800–2100 m) showed the strongest negative (–0.463). In the third function, low elevation had the highest positive (0.253) while high elevation had the strongest negative.
Conclusion: The findings indicate that northern provenances and lower elevations produce larger seeds with higher content. Due to their greater width (diameter) and lower length-to-diameter ratio, these seeds are expected to generate more vigorous seedlings for afforestation. However, such variation in seed size across provenances and elevations may represent genetic and ecological adaptation to local habitats and natural seed predators, serving as a site-specific survival strategy.

Keywords

Main Subjects

References

Alvaninejad, S.; Tabari, M.; Espahbodi, K.; Taghvaei, M.; Hamzepour, M., Morphology and germination characteristics of Quercus brantii Lindl. acorns in nursery. Iranian Journal of Forest and Poplar Research 2010, 17(4), 523-533.
Armstrong, D. P.; Westoby, M., Seedlings from large seeds tolerated defoliation better: a test using phylogeneticaly independent contrasts. Ecology 1993, 74(4), 1092-1100.
Amiri, P.; Soosani, J.; Naghavi, H., Investigating diameter-height models of Persian oak (Quercus brantii Lindl.) in height forests of Middle Zagros. Journal of Forest Research and Development 2024, 10(1), 19-38. (In Persian)
Awasthi, P.; Karki, H.; Bargali, K. I. R. A. N.; Bargali, S. S., Germination and seedling growth of pulse crop (Vigna spp.) as affected by soil salt stress. Current Agriculture Research Journal 2016, 4(2), 159-170.‏
Baker, H. G., Seed weight in relation to environmental conditions in California. Ecology 1972, 53(6), 997-1010.‏
Baraloto, C.; FORGET, P. M.; Goldberg, D. E., Seed mass, seedling size and neotropical tree seedling establishment. Journal of Ecology 2005, 93(6), 1156-1166.‏
Blionis, G. J.; Halley, J. M.; Vokou, D., Flowering phenology of Campanula on Mt Olynipos, Greece. Ecography 2001, 24(6), 696-706.
Castro, J., Seed mass versus seedling performance in Scots pine: a maternally dependent trait. The New Phytologist 1999, 144(1), 153-161.
Fatahi, M., The study of Zagros oak forests and the most important factors of its Destruction. Research Institute of Forests and Rangelands, Tehran 1995. (In Persian)
Gómez, J. M.; Schupp, E. W.; Jordano, P., Synzoochory: the ecological and evolutionary relevance of a dual interaction. Biological Reviews 2019, 94(3), 874-902.
Gómez, J. M.; Bigger is not always better: confl icting selective pressures on seed size in Quercus ilex. Evolution 2004, 58: 71-80.
Gross, K. L., Effects of seed size and growth form on seedling establishment of six monocarpic perennial plants. The Journal of Ecology 1984, 369-387.‏
Gunaga, RP.; Doddabasava, Vasudeva R., Influence of seed size on germination and seedling growth in Karnataka. Journal of Agricultural Sciences 2011, 24: 415-416.
Hammond, D. S.; Brown, V. K., Seed size of woody plants in relation to disturbance, dispersal, soil type in wet neotropical forests. Ecology 1995, 76(8), 2544-2561.
Henareh, J.; Bordbar, S.K.; Pourhashemi, M.; Ghasempour, S., Investigating the structure of degraded oak forest stands in Northern Zagros Forests (Piranshahr and Sardasht forests). Journal of Forest Research and Development 2024, 6(4), 627-643. (In Persian)
Herrera, C.M., Plant animal interactions: an evolutiona approach. Wiley 2002.
Herrera, C. M.; Jordano, P.; Lopez-Soria, L.; Amat, J. A., Recruitment of a mast‐fruiting, bird‐dispersed tree: bridging frugivore activity and seedling establishment. Ecological monographs 1994, 64(3), 315-344.
Karimi Hajipomagh, K.; Zolfaghari, R.; Alvaninejad, S.; Fayyaz, P., Effect of Seed Provenance and Mother Tree of Quercus branti Base on Primary Establishment in Yasuj. Forest and Wood Products 2014, 66(4), 427-439.  (In Persian)‏
Karimi, K.; Zolfaghari, R.; Fayaz, P., The effect of seed morphology and different altitude origins of Persian oak (Quercus brantii Lindl.) on germination and growth of one-year old seedlings. Journal of Wood and Forest Science and Technology 2012, 19(3), 127-141. (In Persian)
Kelly, C. K.; Purvis, A., Seed size and establishment conditions in tropical trees: on the use of relatedness in determining ecological patterns. Oecologia 1993, 94, 356-360.‏
Körner, C., The use of ‘altitude’in ecological research. Trends in ecology & evolution 2007, 22(11), 569-574.
Krannitz, P. G.; Aarssen, L. W.; Dow, J. M., The effect of genetically based differences in seed size on seedling survival in Arabidopsis thaliana (Brassicaceae). American Journal of Botany 1991, 78(3), 446-450.
Larcher, W., Temperature stress and survival ability of Mediterranean sclerophyllous plants. Plant biosystems 2000, 134(3), 279-295.
Leishman, M. R.; Westoby, M., The role of large seed size in shaded conditions: experimental evidence. Functional ecology 1994a, 205-214.
Leishman, M. R.; Westoby, M., The role of seed size in seedling establishment in dry soil conditions--experimental evidence from semi-arid species. Journal of Ecology 1994b, 249-258.‏
Leishman, M. R.; Wright, I. J.; Moles, A. T.; Westoby, M., The evolutionary ecology of seed size. In Seeds: the ecology of regeneration in plant communities 2000, 31-57). Wallingford UK: CABI publishing.‏
Li, M.; Li, W.; Zhao, L., Identification of traits contributing to high and stable yields in different soybean varieties across three Chinese latitudes. Frontiers in plant science 2020,10, 455270.‏
Lichti, N. I.; Steele, M. A.; Swihart, R. K., Seed fate and decision‐making processes in scatter‐hoarding rodents. Biological Reviews 2017, 92(1), 474-504.
Lichti, N. I.; Steele, M. A.; Zhang, H.; Swihart, R. K., Mast species composition alters seed fate in North American rodent‐dispersed hardwoods. Ecology 2014, 95(7), 1746-1758.
Mao, P.; Kan, X.; Pang, Y.; Ni, R.; Cao, B.; Wang, K.; Dong, J., Effects of forest gap and seed size on germination and early seedling growth in Quercus acutissima plantation in Mount Tai, China. Forests 2022, 13(7), 1025.
Mataji, A.; Abdi, F.; Etemad, V.; Kiadaliri, H., Effects of seed origin on survival morphology and growth of Iranian oak (Quercus brantii Lindl.). Iranian Journal of Forest 2016, 8(1), 11-22.
McConnaughay, K. D. M.; Bazzaz, F. A., The relationship between gap size and performance of several colonizing annuals. Ecology 1987, 68(2), 411-416.‏
Mohammadi Alaghoz, R; Darvishzadeh, R.; Alijanpour, A.; Razi, M., Assessment of relationship between morphological variability in sumac population and environmental variants by canonical correlation analysis. Journal of Forest Research and Development 2021, 6(4): 627-643. (In Persian)
Mohit Gera, M. G.; Neelu Gera, N. G.; Gupta, B. N., Preliminary observations on genetic variability and character association in Dalbergia sissoo Roxb. Indian Forester 2000, 134, 608-615.
Moles, A. T.; Westoby, M., Latitude, seed predation and seed mass. Journal of biogeography 2003, 30(1), 105-128.‏
Moles, A. T.; Ackerly, D. D.; Tweddle, J. C.; Dickie, J. B.; Smith, R.; Leishman, M. R.; Westoby, M., Global patterns in seed size. Global ecology and biogeography 2007, 16(1), 109-116
Moore, J. E.; McEuen, A. B.; Swihart, R. K.; Contreras, T. A.; Steele, M. A., Determinants of seed removal distance by scatter‐hoarding rodents in deciduous forests. Ecology 2007, 88(10), 2529-2540.‏
Pandey, R.; Bargali, S. S.; Bargali, K., Does seed size affect water stress tolerance in Quercus leucotrichophora A. camus at germination and early seedling growth stage. Biodiversity International Journal 2017, 1(00005).
Perea, R.; San Miguel, A.; Gil, L., Acorn dispersal by rodents: the importance of re-dispersal and distance to shelter. Basic and Applied Ecology 2011, 12(5), 432-439.‏
Pesendorfer, M. B.; Baker, C. M.; Stringer, M.; McDonald‐Madden, E.; Bode, M.; McEachern, A. K.; Sillett, T. S., Oak habitat recovery on California's largest islands: scenarios for the role of corvid seed dispersal. Journal of Applied Ecology 2018, 55(3), 1185-1194.
Pesendorfer, M. B.; Sillett, T. S.; Koenig, W. D.; Morrison, S. A., Scatter-hoarding corvids as seed dispersers for oaks and pines: a review of a widely distributed mutualism and its utility to habitat restoration. The Condor: Ornithological Applications 2016, 118(2), 215-237.‏
Quero, J. L.; Villar, R.; Marañón, T.; Zamora, R.; Poorter, L., Seed‐mass effects in four Mediterranean Quercus species (Fagaceae) growing in contrasting light environments. American Journal of Botany 2007, 94(11), 1795-1803.
Salazar, R. O. D. O. L. F. O., Seed and seedling provenance variation under greenhouse conditions of Pinus caribaea var. hondurensis Barr et Golf. Revista IPEF 1986, 32, 25-32.‏
Schneider, C. A.; Rasband, W. S.; Eliceiri, K. W., NIH Image to ImageJ: 25 years of image analysis. Nature methods 2012, 9(7), 671-675.
Schupp, E. W.; Fuentes, M., Spatial patterns of seed dispersal and the unification of plant population ecology. Ecoscience 1995, 2(3), 267-275.‏
Seiwa, K.; Kikuzawa, K., Phenology of tree seedlings in relation to seed size. Canadian Journal of Botany 1991, 69(3), 532-538.‏
Seiwa, K., Effects of seed size and emergence time on tree seedling establishment: importance of developmental constraints. Oecologia 2000, 123, 208-215.
Shahi, C.; Vibhuti, K. B.; Bargali, S. S., How seed size and water stress affect the seed germination and seedling growth in wheat varieties. Current Agriculture Research Journal 2015, 3(1), 60-68.‏
Steele, M. A.; Carlson, J. E.; Smallwood, P. D.; McEuen, A. B.; Contreras, T. A.; Terzaghi, W. B., 14 Linking Seed and Seedling Shadows: A Case Study in the Oaks (Quercus). Seed dispersal 2007, 322.
Theimer, T. C., Intraspecific variation in seed size affects scatterhoarding behaviour of an Australian tropical rain-forest rodent. Journal of Tropical Ecology 2003, 19(1), 95-98.‏
Totland, Ø.; Birks, H. J. B., Factors influencing inter‐population variation in Ranunculus acris seed production in an alpine area of southwestern Norway. Ecography 1996, 19(3), 269-278.
Urbieta, I. R.; Perez-Ramos, I. M.; Zavala, M. A.; Maranon, T.; Kobe, R. K., Soil water content and emergence time control seedling establishment in three co-occurring Mediterranean oak species. Canadian Journal of Forest Research 2008, 38(9), 2382-2393.‏
Vander Wall, S. B., How plants manipulate the scatter-hoarding behaviour of seed-dispersing animals. Philosophical Transactions of the Royal Society B: Biological Sciences 2010, 365(1542), 989-997.
Vander Wall, S. B., Masting in animal‐dispersed pines facilitates seed dispersal. Ecology 2002, 83(12), 3508-3516.
Wang, B.; Ives, A. R., Tree-to-tree variation in seed size and its consequences for seed dispersal versus predation by rodents. Oecologia 2017, 183, 751-762.
Zhang, S.; Kang, H.; Yang, W., Climate change-induced water stress suppresses the regeneration of the critically endangered forest tree Nyssa yunnanensis. PLoS ONE 2017, 12, e0182012.
Zolfaghari, R.; Nazari, M.; Karimi, Kh.; Fayyaz, P.; Alvaninejad, S., Relation between seed morphological characteristics of three native oak species of Zagros with germination characteristics and seedling growth. Journal of Forest and Wood Products 2012, 65(1), 33-45.
Zwolak, R.; Crone, E. E., Quantifying the outcome of plant–granivore interactions. Oikos 2012, 121(1), 20-27.
Forest Research and Development
Volume 11, Issue 2
September 2025
Pages 223-248

Files

Share

How to cite

Statistics