The maintenance of stable yield and high genetic diversity in the agricultural heritage torreya tree system
Tóm tắt
Understanding how traditional agriculture systems have been maintained would help design sustainable agriculture. In this study, we examined how farmers have used two types of local trees (Torreya grandis) for stable yield and maintaining genetic diversity in the “globally important agricultural heritage torreya tree system”. The two type of torreya trees are grafted torreya (GT) tree and non-grafted-torreya (NGT) tree. The GT tree has only female and was used to produced seed yields. The NGT tree has both male and female and was used to support GT tree by providing pollens and rootstocks. We first tested the ratio of GT tree to NGT tree, their age groups, ratio of female trees (including GT and NGT trees) to male, and the flowering period of GT and NGT trees. We then tested seed yields and genetic diversity of GT and NGT trees. We further tested gene flow among NGT trees, and the relationship of gene flow with exchange rates of pollens and seeds. GT and NGT trees (male and female) were planted in a mosaic pattern with a ratio of 4:1 (GT:NGT). In this planting pattern, one NGT male trees provided pollen for 20 female trees of GT and NGT. The trees were classified into four age groups (I = 100–400 years old; II = 400–700 years old; III = 700–1000 years old; and IV = 1000–1300 years old) based on basal diameter. The entire flowering period was longer for NGT trees than for GT trees that ensured GT trees (which lack of males) being exposed to pollens. GT tree had high and stable seed yield that increased with age groups. High genetic diversity has been maintained in both rootstocks of the GT trees and NGT trees. There was a strong gene flow among NGT trees, which positive correlated with the exchange rates of pollens and seeds. Our results suggest that farmers obtain stable seed yields, and maintain high genetic diversity by ingeniously using the local GT tree as yield producer and NGT tree as supporter. These GT and NGT trees together ensure sustainable torreya production.
Tài liệu tham khảo
Altieri MA. Linking ecologists and traditional farmers in the search for sustainable agriculture. Front Ecol Environ. 2004;2:35–42.
Achtak H, Ater M, Oukabli A, Santoni S, Kjellberg F, Khadari B. Traditional agroecosystems as conservatories and incubators of cultivated plant varietal diversity: the case of fig (Ficus carica L.) in Morocco. BMC Plant Biol. 2010;10:1–12.
Jarvis DI, Brown AHD, Cuong PH, Collado-Panduro L, Latournerie-Moreno L, Gyawali S, et al. A global perspective of the richness and evenness of traditional crop-variety diversity maintained by farming communities. Proc Natl Acad Sci USA. 2008;105:5326–31.
Labeyrie V, Thomas M, Muthamia ZK, Leclerc C. Seed exchange networks, ethnicity, and sorghum diversity. Proc Natl Acad Sci USA. 2016;113:98–103.
Ren WZ, Hu LL, Guo L, Zhang J, Tang L, Zhang ET, et al. Preservation of the genetic diversity of a local common carp in the agricultural heritage rice–fish system. Proc Natl Acad Sci USA. 2018;115:E546–54.
Xie J, Hu LL, Tang JJ, Wu X, Li NN, Yuan YG, et al. Ecological mechanisms underlying the sustainability of the agricultural heritage rice–fish coculture system. Proc Natl Acad Sci USA. 2011;108:E1381–7.
Aerts R, Berecha G, Honnay O. Protecting coffee from intensification. Science. 2015;347:139.
Wang B, Min QW. The Kuaiji Mountain ancient torreya population. Beijing: China Agriculture Press; 2015.
Leslie AB, Beaulieu JM, Rai HS, Crane PR, Donoghue MJ, Mathews S. Hemisphere-scale differences in conifer evolutionary dynamics. Proc Natl Acad Sci USA. 2012;109:16217–21.
Chen ZD, Chen ZL, Hou LB, Xu ZY, Zheng HC. The preventive effect of the oil from the seed of Torreya grandis cv. merrillii on experimental atherosclerosis in rats. J Chin Med Mater. 2002;23:551–3.
Ni Q, Gao Q, Yu W, Liu X, Xu G, Zhang Y. Supercritical carbon dioxide extraction of oils from two Torreya grandis varieties seeds and their physicochemical and antioxidant properties. Food Sci Technol. 2015;60:1226–34.
Barazani O, Waitz Y, Tugendhaft Y, Dorman M, Dag A, Hamidat M, et al. Testing the potential significance of different scion/rootstock genotype combinations on the ecology of old cultivated olive trees in the southeast Mediterranean area. BMC Ecol. 2017;17:3.
Liu YS. Graft hybridization of fruit plants and its application. J Fruit Sci. 1999;16:20–6.
Xu YT, Min QW, Bai YY, Yuan Z, Wang B, He L, et al. Evaluation of agricultural multi-functional value of the living ancient Torreya grandis community in Kuaiji mountain. J Ecol Rural Environ. 2013;29:717–22.
Wang KJ, Li XH. Genetic characterization and gene flow in different geographical-distance neighbouring natural populations of wild soybean (Glycine soja Sieb. & Zucc.) and implications for protection from GM soybeans. Euphytica. 2012;186:817–30.
Wright S. Evolution in mendelian populations. Genetics. 1931;16:97–159.
Barrett SCH, Hough J. Sexual dimorphism in flowering plants. J Exp Bot. 2013;64:67–82.
Ortiz PL, Arista M, Talavera S. Low reproductive success in two subspecies of Juniperus oxycedrus L. Int J Plant Sci. 1998;159:843–7.
Barrett SCH, Yakimowski SB, Field DL, Pickup M. Ecological genetics of sex ratios in plant populations. Philos Trans R Soc B Biol Sci. 2010;365:2549–57.
Friedman J, Barrett SCH. Wind of change: new insights on the ecology and evolution of pollination and mating in wind-pollinated plants. Ann Bot. 2009;103:1515–27.
Allphin L, Windham MD, Harper KT. Genetic diversity and gene flow in the endangered dwarf bear poppy, Arctomecon humilis (Papaveraceae). Am J Bot. 1998;85:1251–61.
Loaisiga CH, Rocha O, Brantestam AK, Salomon B, Merker A. Genetic diversity and gene flow in six accessions of Meso-America teosintes. Genet Resour Crop Evol. 2012;59:95–111.
Frankham R. Genetic rescue of small inbred populations: meta-analysis reveals large and consistent benefits of gene flow. Mol Ecol. 2015;24:2610–8.
Ennos RA. Estimating the relative rates of pollen and seed migration among plant populations. Heredity. 1994;72:250–9.
Husband BC, Barrett SCH. A metapopulation perspective in plant population biology. J Ecol. 1996;84:461–9.
Deletre M, McKey DB, Hodkinson TR. Marriage exchanges, seed exchanges, and the dynamics of manioc diversity. Proc Natl Acad Sci USA. 2011;108:18249–54.
Pautasso M, Aistara G, Baenaud A, Caillon S, Clouvel P, Coomes OT, et al. Seed exchange networks for agrobiodiversity conservation. A review. Agron Sustain Dev. 2013;33:151–75.
Louwaars NP. Plant breeding and diversity: a troubled relationship? Euphytica. 2018;214:114.
Wright SI, Gaut BI. Molecular population genetics and the search for adaptive evolution in plants. Mol Biol Ecol. 2005;22:506–19.
Parzies HK, Spoor W, Ennos RA. Inferring seed exchange between farmers from population genetic structure of barley landrace Arabi Aswad from Northern Syria. Genet Resour Crop Evol. 2004;51:471–8.
Pusadee T, Jamjod S, Chiang YC, Rerkasem B, Schaal AB. Genetic structure and isolation by distance in a landrace of Thai rice. Proc Natl Acad Sci USA. 2009;106:13880–5.
Pusadee T, Oupkaew P, Rerkasem B, Jamjod S, Schaal BA. Natural and human-mediated selection in a landrace of Thai rice (Oryza sativa). Ann Appl Biol. 2014;165:280–92.
R Core Team. R: a language and environment for statistical computing. Vienna: R Foundation for Statistical Computing; 2016.
Parker AJ, Peet RK. Size and age structure of conifer forests. Ecology. 1984;65:1685–9.
Li YY, Wang XR, Huang CL. Key street tree species selection in urban areas. Afr J Agric Res. 2011;6:3539–50.
Taberlet P, Gielly L, Pautou G, Bouvet J. Universal primers for amplification of 3 noncoding regions of chloroplast DNA. Plant Mol Biol. 1991;17:1105–9.
Takezaki N, Nei M, Tamura K. POPTREE2: software for constructing population trees from allele frequency data and computing other population statistics with windows interface. Mol Biol Evol. 2010;27:747–52.
Nei M. Genetic distance between populations. Am Nat. 1972;106:283–92.
Do C, Waoles RS, Peel D, Macbeth GM, Tillett BL, Ovenden JR. NEESTIMATOR v2: re-implementation of software for the estimation of contemporary effective population size (N e) from genetic data. Mol Ecol Resour. 2014;14:209–14.
Piry S, Luikart G, Cornuet JM. BOTTLENECK: a computer program for detecting recent reductions in the effective population size using allele frequency data. J Hered. 1999;90:502–3.
Beerli P, Felsenstein J. Maximum likelihood estimation of a migration matrix and effective population sizes in subpopulations by using a coalescent approach. Proc Natl Acad Sci USA. 2001;98:4563–8.
Beerli P. Comparison of Bayesian and maximum-likelihood inference of population genetic parameters. Bioinformatics. 2006;22:341–5.
Smouse PE, Long JC, Sokal RR. Multiple-regression and correlation extensions of the mantel test of matrix correspondence. Syst Zool. 1986;35:627–32.