71 Annales Universitatis Paedagogicae Cracoviensis Studia Naturae, 1: 71–84, 2016, ISSN 2543-8832 Noel A. González-Valdivia1, William Cetzal-Ix1*, Saikat Kumar Basu2, Isidra Pérez-Ramírez1, Jesús F. Martínez-Puc1, Peiman Zandi3 1 Instituto Tecnológico de Chiná, Calle 11 entre 22 y 28, Colonia Centro Chiná 24050, Campeche, México, *rolito22@hotmail.com 2 Department of Biological Sciences, University of Lethbridge, Lethbridge, AB Canada T1K 3M4 3 Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, People’s Republic of China Conservation of the genetic diversity of local corn (Zea mays L.) in the Yucatan Peninsula, Mexico Introduction Maize (Zea mays L.) is an important cereal member which is historically associat- ed with the original human populations that once populated and till now continues inhabiting the vast and biodiverse continents of the Americas (Serratos-Hernández, 2000). Corn seeds have been reported from several archaeological sites across the Americas dating back as old as 5000 years (Arteaga et al., 2016). Several scholars and researchers consider that the origin of human is inherently associated with the evo- lution of corn, for example the Ch’ol ethnicity is recognized with the phrase “men of corn” (Cross-Cortés, 2000). �e genetic diversity of this grass family (Poaceae) mem- ber o�ers a perspective of its relevance as food, and numerous ways in which it is used by the indigenous communities across the Americas, where the crop is reported to have originated (Wellhausen et al., 1951). Mexico is one of the most important centers of origin for maize and the most diverse representing 64 landraces (59 natives); along with innumerable varieties and “criollo” or natives hybrids have been identi�ed. �is monumental genetic diversity is the result of the mass selection of the species since it was domesticated from Teo- sintes or similar to those Mesoamerican Teosintes ancestors (Ine-Conabio-Sagarpa, 2008; Arteaga et al., 2016). In the Yucatan peninsula (YP) of Mexico, three maize races (Nal Tel narrower, Dzit Bacal and Xnu’uk Nal or Tuxpeño and two hybrids (Nal Xoy and X’mejen Nal) with restricted distribution have been recorded (Arias et al., 2007). �ese races and hybrids are disappearing fast as a result of technological displacement imposed by improved varieties and commercial hybrids, produced and distributed by giant multi-national corporations. �e genetic erosion due to the subsequent decrease 72 N oe l A . G on zá le z- V al di vi a, W ill ia m C et za l-I x, S ai ka t K um ar B as u, Is id ra P ér ez -R am íre z, J es ús F . M ar tín ez -P uc , P ei m an Z an di in seed banks of the local producers and growers, along with incentive policies of replacing native seeds for higher pro�ts and commercial interests further lead to the loss of local genetic diversity of maize landraces and germplasms in the countryside by both rural youth, as well as aging small and medium range producers “milpero” (Buenrostro, 2009). Such anthropogenic interferences have been creating a  scenario of gradual extinction of the native maize genetic diversity in the YP. Climate change, another signi�cant challenge for agriculture and agri-production, also needs rapid adaptation options to deal with the production constraints. An im- portant line of work in this regard is to rescue the local maize genetic diversity under a  restorative scheme that helps conserving local diversity threatened by several an- thropogenic factors and to study their responses to new environmental rigors, de- Fig. 1. Localities of cultivation and conservation of native germplasms of corn in the Yucatan Peninsula, Mexico 73 termining their ability to continue productivity under the context of highly variable climatic uncertainties. �e main objective of the research has been collecting seeds still used by farmers in their traditional production systems, identifying races and varieties used in YP area and documenting their life cycle and other usage identi�ed by key informants and maize growers and producers. Material and methods �e study was designed based on the review of specialized literature on native corn (Wellhausen et al., 1951; Serratos-Hernández, 2009; Perales-Rivera, Golicher, 2011). To identify the diversity of races and varieties, specialized literature was reviewed and the �elds were located for identifying the possible races and varieties that have been recorded in the YP (Tab. 1 – Appendix); priority areas of cultivation and con- servation of native germplasms of corn were visited (Fig. 1). Subsequently, seeds of landraces were purchased in �ve rural seed fairs (trade shows) in di�erent areas of the YP (Fig. 2). It is important to mention that such traditional rural fairs are signif- icant resource centers where seeds of local landraces and germplasms of maize are sold and exchanged among local farmers and producers. Also in these local events short interviews were successfully conducted with producers, who answered ques- tions about documenting their experiences and sharing traditional knowledge re- garding the life cycles of various local maize varieties, the best time of planting and possible partnering with other cultivated species and the source of seeds. In each locality visited (Fig. 1), several corncobs were collected to characterize morphology (number of rows per cobs, number of grains per row and along the cob) (Fig. 3–4) and their performance or yield. Results Races, varieties and hybrids �e principal �nding with respect to native corn varieties registered in the YP is that these are still in places considered “Maya centers of resistance”. However, the quanti- ty and quality of seed available has been reduced, mainly due to severe drought con- ditions and increased pest pressures. Nevertheless, some native varieties were di�cult to �nd, such as Nal Tel blanco or Sak Nal Tel (Fig. 3A), which is characterized by be- ing precocious corn, high quality, �our, and drought tolerant. �e same situation ap- pears true for all varieties to a  lesser or greater degree. On the other hand, the pres- ence of two additional races has been recorded in the YP: Palomero Amarillo (Yel- low Palomero) (Fig. 3B) and Tabloncillo (Fig. 4). With respect to the conservation C onservation of the genetic diversity of local corn (Zea m ays L.) in the Y ucatan P eninsula, M exico 74 N oe l A . G on zá le z- V al di vi a, W ill ia m C et za l-I x, S ai ka t K um ar B as u, Is id ra P ér ez -R am íre z, J es ús F . M ar tín ez -P uc , P ei m an Z an di Fig. 2. Localities of rural seed fairs or corn (trade show) in the Yucatan Peninsula, Mexico of maize germplasm, �ve varieties: red-white-yellow Nal Tel (Fig. 3C), white-yellow Dzit Bacal (Fig. 3D), white-yellow-red (also known as Chac Chu’ub) Xnu’uk Naal or Tuxpeño, blue Xnu’uk Naal (also known as Eh Hu), Yellow Palomeroand Tabloncil- lo and several hybrids: Xnu’uk Nal (cross between Nal Tel with Tuxpeño), yellow Nal Xoy (possible tri-hybrid between Nal Tel and Xnu’uk Nal) (Fig. 3G), White Nal Xoy (cross between Nal Tel, Tuxpeño and variety), X’mejen Nal (cross between Nal Tel and Dzit Bacal), Chac Xmejen Nal (tri-hybrid between Chac Chu’ub and X’mejen Nal) (Fig. 3H), San Pableño, red Nal Tel (cross between Nal Tel with Chac Ch’ub), Yellow Nal Tel (possible cross between Nal Tel and Nal Xoy) were recovered (Appendix 1 – Tab. 1). Relevant agroecological characteristics �e varieties registered are characterized by lifecycles, presenting three main classes: precoces (lower lifecycle at 80 days), intermediate (80–110 days) and late (over 110 days). In the germplasm enhancement of maize, the Maya people have made cross 75 Fig. 3. Races, varieties and hybrids of corn; a  – Nal Tel blanco or Sak Nal Tel, B – Palomero Amarillo (Yellow Palomero), C – Red Nal Tel, D – yellow Nal Tel, E – White Dzit Bacal, F – Eh Hu, G – Yellow Nal Xoy, H – Chac Xmejen Nal (Photo. W. Cetzal-Ix) C onservation of the genetic diversity of local corn (Zea m ays L.) in the Y ucatan P eninsula, M exico 76 N oe l A . G on zá le z- V al di vi a, W ill ia m C et za l-I x, S ai ka t K um ar B as u, Is id ra P ér ez -R am íre z, J es ús F . M ar tín ez -P uc , P ei m an Z an di Fig. 4. Tabloncillo race of Corn (Photo. W. Cetzal-Ix) Tab. 1. Provenances collected between 2015 and 2016 of native varieties of corn in Yucatan and Campeche, Mexico * Number of collections Variety Campeche* Yucatan* Lifecycle Can Dzit Bacal 2 0 Intermediate Can Nal Tel 1 1 Precocious Can Nal Xoy 0 2 Intermediate Can San Pableño 1 0 Late Can Xmejen Naal 0 2 Intermediate Can Xnu’uk Naal 0 1 Late Chac Chu’ub 1 2 Late Chac Xmejen Naal 0 3 Intermediate Chak Nal Tel 1 1 Precocious Eh Hu 3 2 Late Mixto 1 0 Late Yellow Palomero 1 2 Precocious Pix Cristo 2 0 Late Sak Dzit Bacal 1 0 Intermediate Sak Nal Tel 3 0 Precocious Sak Nal Xoy 0 2 Intermediate Sak Tux 2 0 Late Sax Tux (long insertion) 1 0 Late Sak Xmejen Naal 0 1 Intermediate Sak Xnu’uk Naal 1 0 Late Sak San Pableño 3 0 Late Santa Rosa 1 0 Late Tabloncillo 0 1 Late Tuxpeño 1 0 Late 77 that allows to combine the characteristics of the lifecycle with the organoleptic char- acteristics of the grains, which has allowed the emergence in the collections of hybrid double and even triple. For example, Chac Xmejen Nal (Fig. 3H) is a reddish corn of intermediate lifecycle (75–80 days), probably from the cross product of Chac Chu’ub of red color with Xmejen Nal (hybrid between Nal Tel and Xnu’uk Nal) or with preco- cious varieties of Nal Tel of red color (Chu’ub Nal Tel) (Fig. 3C). Of the 47 samples collected at di�erent sites visited, 10 belong to precocious vari- eties (Nal Tel and Palomero), 14 to intermediate (Dzit Bacal, Xmejen Naal, Nal Xoy) and 23 correspond to late (Xnu’uk Naal and Tabloncillo) types. �e characteristics of cobs of di�erent races, varieties and provenances that facilitate distinguishing them and their values are shown in table 1. Of the total of 25 varieties registered, 18 were reported in Campeche and 13 in Yucatan (Tab. 2). In Quintana Roo, it was not possi- ble to �nd sources of native maize, except for Xmejen Naal; for which so far no data has been generated. Quintana Roo producers indicate that seeds have been lost due to recurrent drought occurring in the state. �e set of late-type corn, the Xnu’uk Naal race, shows the greatest number of records and provenances. �e varieties that were found during expeditions between 2015 and 2016 allowed to determine that native corn germplasm preserved in Campeche and Yucatan be- long to the three groups that are subdivided according to their lifecycle and harvest. Materials with long cycles (late) are prevalent in the state of Campeche compared to precocious and intermediate types. �e opposite is observed in Yucatan, where corns’ intermediate cycles were more common among communities where native corn is 6 3 16 4 10 7 0 4 8 12 16 20 Precocious Intermediate Late Pr ov en an ce s of n at iv e co rn Campeche Yucatan Fig. 5. Number of provenances in which native varieties are reported based on the lifecycle of the varieties collected in the states of Campeche and Yucatan, Mexico C onservation of the genetic diversity of local corn (Zea m ays L.) in the Y ucatan P eninsula, M exico 78 N oe l A . G on zá le z- V al di vi a, W ill ia m C et za l-I x, S ai ka t K um ar B as u, Is id ra P ér ez -R am íre z, J es ús F . M ar tín ez -P uc , P ei m an Z an di cultivated; although late corns also represent a signi�cant proportion of the diversity of this crop (Fig. 5). Discussion �e diversity of races and varieties of corn in the Yucatan Peninsula that have been identi�ed in the region include races mentioned by Wellhausen et al. (1951) and Arias et al. (2007) with addition of Tabloncillo and Reventador (Yellow Palomero) races. �ere is evidence to some gene �ow that might have occurred due to the migration of people from rural areas to other parts of Mexico, which have brought seeds that then thrive in their communities. �e other alternative is that this evidence may not have been detected in the Peninsula of Yucatan in previous studies. For example, the Tabloncillo (Fig. 4) race has been mentioned to be present in the Gulf of Mexico side. Gene �ow has been mentioned by Perales-Rivera and Golicher (2011) as an active process between nine provinces and six biocultural centers of origin and diversity of native maize in Mexico. �e Olotillo race, that has been mentioned by Lazos and Cheauvet (2012) to be found in Campeche, is a possible reference to Eh Hu variety, dark purple, o�en located in di�erent sub-regions of the state and generally in the peninsular region. However, other authors report this as the Eh Hu that is part of the Xnu’uk Naal (Tuxpeño) race. �e late varieties seem to dominate the current scenario of diversity of native maize germplasm in the Yucatan Peninsula, followed by varieties and hybrids with intermediate lifecycles. �is has been mentioned as a preference by Arias et al. (2007). Against the context of possible climate change scenarios, that predicts an increase in the frequency and intensity of the phenomenon of drought; thereby reducing the pres- ence of early varieties that may limit the adaptation options for corn producers in the region. Based on the results obtained, it can be concluded that the genetic diversity of native maize in the Yucatan Peninsula still remains; based on records and collections of germplasm conducted in 2015 and 2016, represented by the same range of races and varieties that have historically been reported for the region (Wellhausen et al., 1951; Arias et al., 2007; Serratos-Hernández, 2009; Arteaga et al., 2016). Cazares-Sánchez et al. (2015) mentioned that Nal Tel has an average of 22 grains per row, under the results (26 grains per row) in varieties of cobs collected between 2015–2016. Also, for varieties like Xnu’uk Naal, these authors mention an average of 40 grains per row, coinciding with the average obtained in the varieties that are pre- sented in this study. For the state of Campeche, a predominance of maize varieties of late lifecycle is detected and in the Yucatan Peninsula of intermediate lifecycle coin- ciding with Arias et al. (2007), who mentioned that the region has been demonstrat- ing declining use of precocious varieties and increasing the number of varieties with 79 longer cycles, which may result in a change of production systems to those of tempo- rary irrigation. Varieties with longer periods in their growth and developments tend to produce higher grain yield per unit area. �en the Xnu’uk Naal (Tuxpeño) races are likely to continue to prevail in the region, while precocious Nal Tel race, belonging to the ancient races in Mexico (Wellhausen et al., 1951), appears to decline. Particularly Gallito white (Sak Nal Tel), which was obtained only in small quantities in the Chenes region in Campeche, is quite vulnerable. A new contribution to the region constitutes the collections of the Yellow Palome- ro (near Reventador precocious) race and the appearance has strong similarity in their morphometry to Tabloncillo race; which may indicate germplasm movement by ex- change of seeds or due to the impact of migrant population in the region. Both ma- terials were documented in the area of Peto, in Yucatan; that also highlights to be the main source of several varieties of native corn for the Yucatan Peninsula in this study. Acknowledgments �e �rst author would like to acknowledge PRODEP ITCHN-PTC support of the project Rescate de germoplasma de maíz criollo y acriollado en la Península de Yucatán (number of o�ce DSA/103.5/15/6793). References Arias, L.M., Latournerie, L., Montiel, S., Sauri, E. (2007). Cambios recientes en la diversidad de maíces criollos de Yucatán, México. Universidad y Ciencia, 23(1), 69–73. [In Spanish] Arteaga, M.C., Moreno-Letelier, A., Mastretta-Yanes, A., Vázquez-Lobo, A., Breña-Ochoa, A., More- no-Estrada, A., Eguiarte, L.E., Piñero, D. (2016). Genomic variation in recently collected maize lan- drace from Mexico. Genomics Data, 7, 38–45. DOI: 10.1016/j.gdata.2015.11.002 Buenrostro, M. (2009). �e bene�ts of the corn�elds. Ciencias, 92, 30–32. [In Spanish] Cázares-Sánchez, E., Chávez-Servia, J.L., Salinas-Moreno, Y., Castillo-González, F., Ramírez-Vallejo, P. (2015). Grain composition variation among native maize (Zea mays L.) of Yucatan, Mexico. Agro- ciencia, 49(1), 15–30. Cruz-Cortés, N. (2000). Los hombres de barro y los hombres de maíz. Estudios Mesoaméricanos, 1, 24–30. [In Spanish] Ine-Conabio-Sagarpa. (2008). Documentos de trabajo para el taller: Agrobiodiversidad en México. El caso del maíz. Dirección de Economía Ambiental (INE), Comisión Nacional para el Conocimiento y Uso de la Biodiversidad (CONABIO), Sistema Nacional de Recursos Fitogenéticos para la Aliment- ación y la Agricultura (Sagarpa), México. [In Spanish] Lazos, E., Cheauvet, M. (2012). Análisis del contexto socio y biocultural de las colectas de maíces nativos en México. Proyecto Global de Maíces Nativos. Comisión Nacional para el Conocimiento y Uso de la Biodiversidad (CONABIO), México. [In Spanish] Perales-Rivera, H., Golicher, D. (2011). Modelos de distribución para las razas de maíz en México y pro- puesta de centros de diversidad y de provincias bioculturales. Comisión Nacional para el Conocimiento y Uso de la Biodiversidad (CONABIO), México. [In Spanish] Serratos-Hernández, J.A. (2009). El origen y la diversidad del maíz en el continente americano. Green- peace, México. [In Spanish] Wellhausen, E., Roberts, L., Hernández, E., Mangeldorf, P.C. (1951). Razas de maíz en México. Su origen, características y distribución. Programa de Agricultura Cooperativo de la Secretaría de Agricultura y Ganadería, Fundación Rockefeller, México. [In Spanish] C onservation of the genetic diversity of local corn (Zea m ays L.) in the Y ucatan P eninsula, M exico 80 N oe l A . G on zá le z- V al di vi a, W ill ia m C et za l-I x, S ai ka t K um ar B as u, Is id ra P ér ez -R am íre z, J es ús F . M ar tín ez -P uc , P ei m an Z an di Appendix 1 Tab. 1. Races, varieties and characteristics of native corn cob collected between 2015 and 2016 in the Yucatan Peninsula, Mexico. Yucatan Peninsula states: CAM – Campeche, QROO – Quintana Roo, YUC – Yucatan, C – Colonical, Cl – Cylindrical, Co – Cónico, ND – no data collection cobs Group Race Variety (hybrid*) Provenances Grain color Cob long [cm] Row per cob Grains per row Cob shape Pr ec os io us Nal Tel Sak Nal Tel Suc-Tuc [CAM] white 11 14 30 C Sak Nal Tel Hopelchén [CAM] white 11 15 18 C Sak Nal Tel Sahcabchén [CAM] white 14 14 23 C Chak Nal Tel Xoy, Peto [YUC] red 11 14 25 C Chak Nal Tel Tikinmul [CAM] red 12 14 27 C K’an Nal Tel Peto [YUC] yellow 11 14 28 C K’an Nal Tel Suc-Tuc [CAM] yellow 14 16 28 C K’an Nal Tel Xbox [YUC] yellow 10 12 24 C K’an Nal Tel Chacsinkín, Peto [YUC] yellow 13 15 28 C Palomero Yellow Palomero Peto [YUC] yellow 12 12 33 Cl Yellow Palomero Timul [YUC] yellow 9 13 24 Cl Yellow Palomero Tikinmul [CAM] yellow 10 12 33 Cl In te rm ed ia te Dzit Bacal Chac Dzit Bacal Hopelchén [CAM] red- dish ND ND ND ND K’an Dzit Bacal Suc-Tuc [CAM] yellow ND ND ND Cl K’an Dzit Bacal Dzutoh, Timul [YUC] yellow 14 14 33 Cl Sak Dzit Bacal Dos Lagunas Norte, Calakmul [CAM] white 19 12 43 Cl Sak Dzit Bacal Dzutoh, Timul [YUC] white 13 12 35 Cl Sak Dzit Bacal Peto [YUC] white 19 12 47 Cl Dzit Bacal por Nal Tel Sak Xmejen Naal* Timul [YUC] white 12-16 12-14 29-35 Cl Sak Xmejen Naal* Blanca Flor, Ba- calar (QROO] white ND ND ND ND Sak Xmejen Naal* Sabacché [YUC] white 17 14 39 Cl Sak Xmejen Naal* Dzutoh [YUC] white 15 14 32 Cl K’an Xmejen Naal* Peto [YUC] yellow ND ND ND ND 81 In te rm ed ia te K’an Xmejen Naal* Dzutoh, Timul [YUC] yellow 14 14 32 Cl Chac Chu’ub por X’mejen Nal Chac Xme- jen Naal* Peto [YUC] red 16 15 32 C Chac Xme- jen Naal* Box [YUC] dark red 14 13 32 Co Chac Xme- jen Naal* Dzutoh, Timul [YUC] red 19 13 39 Co Xnu’uk Naal por Nal Tel Sak Nal Xoy* Xoy, Peto [YUC] white 19 12 46 Co Sak Nal Xoy* Dzutoh, Timul [YUC] white 16 16 27 Co K’an Nal Xoy* Xoy, Peto [YUC] yellow 19 16 36 Co Xnu’uk Naal x Nal Tel K’an Nal Xoy Dzutoh, Timul [YUC] yellow 17 12 38 Co La te Xn’´uk Naal Chac Chu’ub Dos Lagunas Norte, Calakmul, [CAM] red 17 13 27 Cl Chac Chu’ub Timul [YUC] red 16 13 36 Cl Chac Chu’ub Xoy, Peto [YUC] red 17 16 42 Cl Pix Cristo Dos Lagunas Norte, Calakmul [CAM] white with red 20 12 33 Cl Pix Cristo Suc-Tuc [CAM] white with red 21 8 50 Cl K’an Xnu’uk Naal Peto [YUC] yellow ND ND ND ND Sak Xnu’uk Naal Sahcabchén [CAM] white 18 14 42 Cl Sak Xnu’uk Naal Sabacché [YUC] white 18 10 45 Cl Sak Xnu’uk Naal Suc-Tuc [CAM] white 15 12 32 Cl Sak Xnu’uk Naal Peto [YUC] white 18 14 26 Cl Eh Hu Xoy, Peto [YUC] purple 18 12 44 Cl Eh Hu Dzutoh, Timul [YUC] purple 16 12 39 Cl Eh Hu Xmabén, Calak-mul [CAM] purple ND ND ND ND Eh Hu Suc-Tuc [CAM] purple 18 12 44 Cl Eh Hu Los Laureles [CAM] purple ND ND ND ND Sak Tux Suc-Tuc [CAM] white ND ND ND Cl Sak Tux Xmabén, Calak-mul [CAM] white ND ND ND ND C onservation of the genetic diversity of local corn (Zea m ays L.) in the Y ucatan P eninsula, M exico 82 N oe l A . G on zá le z- V al di vi a, W ill ia m C et za l-I x, S ai ka t K um ar B as u, Is id ra P ér ez -R am íre z, J es ús F . M ar tín ez -P uc , P ei m an Z an di La te Sax Tux (long inser- tion) Dos Lagunas Norte, Calakmul [CAM] white 16 14 34 Cl Santa Rosa Xmabén, Calak-mul [CAM] yellow ND ND ND ND Mixed ux- peño Nohacal [CAM] white 17 16 4.3 Cl Los Laureles [CAM] yellow y rojizo ND ND ND ND Sak San Pableño Sahcabchén [CAM] white 17 14 41 Cl Sak San Pableño Sahcabchén [CAM] white 15 13 22 Cl Can San Pableño Sahcabchén [CAM] yellow 16 16 27 Cl Sak Xnu’uk Naal Hopelchén [CAM] white ND 12 37 Cl Tabloncillo Tabloncillo Peto [YUC] purple and white ND 8-12 47 Cl 83 Abstract �e production of native corn at regional level is greatly limited by the seasonality of rainfall, avail- ability of adequate lands, poor fertility status of the soil, high input costs and constraints of re- sources of the local corn growers and/or producers. �e challenges of reduced cultivable area give very little opportunity for increasing production area in a  sustainable manner; it is impor- tant to note that the soil recover its fertility status through crop rotation and prolonged rest pe- riod (>25 years) known as sequential agroforestry system or “milpa”. During 2015, corn collec- tions were performed in the Yucatan Peninsula, Mexico that included �ve races from the Yu- catan (in localities of Nohacal and Peto) and Campeche (Calakmul, Suc-Tuc, Sakabchen, I Chek) states. �e races identi�ed were: 1) Nal-Tel (gallito), 2) Dzit Bacal, 3) Xnu’uk Naal (Tuxpeño), 4) Palomero and 5) Tabloncillo. �e local varieties, Pix Cristo (Knees of Christ), Eh Hu (Purple maize) and Chac Chu’ub (Chac’s Blood or Red maize), are included within the Tuxpeño (Xnu’uk Naal) race. �e land race of corn that is in imminent danger of extinction is Nal-Tel, characterized by its precocity and ability to escape periods of low rainfall; it is important to rescue it for adoption to the practices of local and regional production. �e adaptation of this race as a germplasm is important due to its resil- ience to climate change itself. Palomero, Tabloncillo, Pix Cristo, Chac Chu’ub and Eh Hu can thus be used in traditional food industry, to preserve the traditional knowledge and to provide opportunities for additional income for the local, rural communities. Yellow Palomero and Tabloncillo races are new records of germplasm for the region; and hence it is essential to exchange their seeds among local pro- ducers and growers. Key words: Campeche, conservation, corn, cultivation, genetic diversity, Mexico, Yucatán Received: [2016.09.07] Accepted: [2016.10.20] Zachowanie różnorodności genetycznej rodzimej kukurydzy (Zea mays L.) na Jukatanie w Meksyku Streszczenie Produkcja rodzimej kukurydzy na poziomie regionalnym jest znacznie ograniczona przez sezonowość opa- dów, dostępność odpowiednich gruntów, zły stan żyzności gleby, wysokie koszty produkcji i ograniczenia zasobów lokalnych plantatorów lub producentów kukurydzy. Apele o zmniejszenie powierzchni upraw- nej dają bardzo małą szansę na zwiększenie powierzchni produkcyjnej w sposób zrównoważony; ważne jest, aby pamiętać, że gleba może odzyskać swój status płodności dzięki płodozmianowi oraz dłuższym okresom spoczynku (>25 lat), zwanym sekwencyjnym systemem agroleśnym lub „milpa”. W 2015 roku na Jukatanie w Meksyku przeprowadzono zbiory kukurydzy, które obejmowały 5 lokalnych odmian z re- gionu Jukatan (w miejscowościach Nohacal i Peto) i Campeche (Calakmul, Suc-Tuc, Sakabchen, I Chek). Zidenty�kowano następujące odmiany: 1) Nal-Tel (gallito), 2) Dzit Bacal 3) Xnu’uk Naal (Tuxpeño), 4) Pa- lomero i 5) Tabloncillo. Lokalne odmiany Pix Cristo (Kolana Chrystusa), Eh Hu (kukurydza purpurowa) i Chac Chu’ub (kukurydza czerwona) obejmowały również odmianę Tuxpeño (Xnu’uk Naal). Nal-Tel jest odmianą kukurydzy, która jest narażona bezpośrednio na niebezpieczeństwo wymarcia. Charakteryzuje się wczesnym rozwojem i zdolnością przetrwania w okresach niskich opadów, co jest ważne dla jej ratowania w celu praktycznego zastosowania w lokalnej i regionalnej produkcji. Przystosowania tej odmiany, jako pla- zmy zarodkowej, są ważne ze względu na jej odporność na zmiany klimatyczne. Palomero, Tabloncillo, Pix Cristo, Chac Chu’ub i Eh Hu mogą być stosowane w tradycyjnej produkcji spożywczej, w celu zachowania wiedzy oraz zapewnienia możliwości dodatkowego dochodu dla lokalnych społeczności wiejskich. Żółte odmiany Palomero i Tabloncillo są nowymi archiwami plazmy zarodkowej dla regionu i dlatego niezbędna jest wymiana ich nasion wśród lokalnych producentów oraz plantatorów. Słowa kluczowe: Campeche, ochrona, kukurydza, uprawa, różnorodność genetyczna, Meksyk, Jukatan C onservation of the genetic diversity of local corn (Zea m ays L.) in the Y ucatan P eninsula, M exico 84 N oe l A . G on zá le z- V al di vi a, W ill ia m C et za l-I x, S ai ka t K um ar B as u, Is id ra P ér ez -R am íre z, J es ús F . M ar tín ez -P uc , P ei m an Z an di Information on the authors Noel A. González-Valdivia Professor and researcher at the Instituto Tecnológico Nacional, SNI Level 1; an agronomist specializing in the rescue, assessment and management of native germplasms adapted to the tropics. Also interested in ethnobiology studies, ecology and sustainable development, which have recently resulted in innovative applications of traditional knowledge in obtaining human products such as biopesticides, medicinal and food products based on �torrecursos utility. He participated in the training of human resources and in the development of initiatives and projects with positive impacts on the rural environment. William Cetzal-Ix Interested in systematics, taxonomy and conservation of neotropical orchids and ferns, as well as in �oris- tic studies of indicator species (epiphytes) conservation of forests of southeastern Mexico, and knowledge and conservation of plants with potential uses (melliferous, medicinal and ornamental). Saikat Kumar Basu Traditionally trained in botany (plant sciences) and specializing in microbiology, works actively in va- rious areas of plant sciences and environmental conservation. �e author works extensively on forage crops with particular reference to annual forage legume and medicinal herb and spice, fenugreek. Cur- rently he is working in biomolecular sciences �eld dealing with plant biotechnology and genetic engine- ering application in small grain cereals like wheat. Eliana Noguera-Savelli Interested mainly in systematics, taxonomy, �oristic and anatomy of neotropical vascular plants, develo- ping research to generate knowledge on biodiversity, exploration of timber and non-timber forest resour- ces and training of human resources to support knowledge, conservation and sustainable use of natural resources. Isidra Pérez-Ramírez Agronomist with a Master of Science in natural resources and rural development specializing in agroe- cosystem management. He is interested in the characterization and geographical distribution of plants in home gardens. Jesús F. Martínez-Puc Extensionist, researcher, and professor interested in the tropical apiculture. Currently developing projects on pest control bees, nutritional quality of nectar and mellifera �ora. Peiman Zandi He was deeply trained in agronomy (crop science) and specializing in stress physiology, biotic/abiotic stresses and agroecology. He is also interested in working in di�erent areas of plant developmental biolo- gy, agroecology, plant nutrition, botany, plant breeding and genetics.