Environmental Conditions, and Phenolic Compounds Potential in the Leaves of Vitis Tiliifolia

The wild vine Vitis tiliifolia is found in Mexico, Central América, and the Caribbean region. In the Veracruz State, in Mexico, grows in several municipalities and is used for nutritional and therapeutic purposes. The geographical distribution and environment where this Vitis grow has not been recorded. The leaves of V. tiliifolia are rich in phenolic compounds but potential areas with vines of high phenolic compounds are unknown. An agroecological zoning model to identify potential areas for the cultivation and development of this species was performed. Potential areas having wild vines of high phenolic compounds in the leaves were also determined. The model included 95 vine georeferences, obtained from four municipalities of central Veracruz. These were analyzed with maximum entropy modeling, mapped with ArcMap software, and correlated with the phenolic compounds found in leaves collected in the georeferenced areas. A zoning map was produced, with a potential area of 2763.72 km 2 , which included the states of San Luis Potosi, Hidalgo, Veracruz, Puebla, Oaxaca, and Chiapas. Agroclimatic variables of seasonality of temperature, precipitation, and organic matter in the soil were the most important for the development of this species. In the state of Veracruz, vines with the potential of high phenolic content were found in 29 municipalities with characteristics suitable for its cultivation. The highest phenolic content potential was found at altitudes between 1000 and 2000 meters in the municipalities of Huatusco and Cosautlán in the State of Veracruz.

The wild Vitis are lianas or climbers that grow with natural tutors of different tree species. In the state of Veracruz grow at altitudes from 0 to 2300 m, on mountain slopes, in gullies, and in some agroecosystems  (Martínez et al., 2009). These studies have been useful for the development of speci c cultural practices, use, and conservation programs. However, there are not agroecological zoning studies for wild grapes, including V. tiliifolia. There is a need for research on natural areas with agroecological potential, with favorable conditions for the conservation and sustainable use of V. tiliifolia considering nutraceutical compounds, such as trans-resveratrol, found in its leaves . Geographical data were collected for 95 wild V. Tiliifolia vines in the four mentioned municipalities using a Garmin GPS Model 010-01508-10. A potential distribution model of V. tiliifolia was developed for the state of Veracruz and for the Mexican country. In addition, using the leaf phenolic data of V. tiliifolia in Alejandro et al. (2020) that indicated 13 compounds, potential production areas of high phenolic content were also identi ed.

Zoning
To develop the distribution model of V. tiliifolia in the state of Veracruz, coordinates were recorded from three sampling points in each of the four municipalities described above, using a Garmin Etrex GPS, with vectorial layers at a scale of 1:250,000 (INEGI, 2018), complemented with bibliographic information on the natural phytogenetic resources of the four municipalities. The cartographic design used ArcMap 10.5 Madeira software. A potential agroecological zoning model for V. tiliifolia was also elaborated for the Mexican country. Maps were elaborated using nineteen climatic layers and one of topography (altitude), with a resolution of 30 seconds of arc, equivalent to ≈ 1 Km 2 at the equatorial plane. The data for cells at each layer included the environmental values of temperature, precipitation, and altitude (Hijmans et Table 2 (https://jast.modares.ac.ir/article-23-27802-en.html).

Results
Zoning and Potential Areas for Cultivation of Vitis tiliifolia The data collected in the municipalities of Ixtaczoquitlán, Huatusco, Atlahuilco, and Cosautlán showed that V. tiliifolia develops at altitudes ranging from 800 to 2300 m (Fig. 1). Different conditions for V. tiliifolia growth in several municipalities of the high mountain region were found (Fig. 2). Of the 29 climatic and pedological variables considered, 19 contributed 100% of the factors of agroecological importance. The contributions of different environmental variables to the agroecological zoning model are shown in Table 1. The most important were precipitation in the driest period (Bio14), with a 42.4% contribution; the elevation (DEM), with 22.7%; organic matter (OM), with 9.7%; precipitation in the wettest period (pp_humid), with 6.7%, and seasonality of precipitation (Bio15), with 5.8%. The AUC value of 0.998 was very close to 1, indicating a good t for the model. Most of the area identi ed by our model was located in the neotropical region, in the southern and southeastern Mexico, which is mountainous (Fig. 3).
The zoning map developed for the Mexican country had six cumulative zone thresholds with agroecological potential for the development of V. tiliifolia, which include the states of San Luis Potosí, Hidalgo, Puebla, Oaxaca, Chiapas, and Veracruz (Fig. 3). Bio7: Annual temperature oscillation (°C); Bio14: Precipitation in the driest period (mm); Bio15: Seasonality of precipitation (mm); pp_humid: precipitation in the wettest period (mm); DEM: Digital elevation model (m); OM: Organic matter; K: potassium; pH; Na: sodium.

Phenolic content potential and environmental conditions
The variables Bio14 (precipitation in the driest period), elevation (DEM), OM (organic matter), pp_humid (precipitation in the wettest period), and Bio15 (seasonality of precipitation) were the most important for the 95 sites of vine sampled variables, and they were correlated with the metabolic compound content in a partial least squares (PLS) analysis (Fig. 4). (The data is supplied in the electronic supplementary material). Bio 14 was correlated mainly with catechin, resveratrol, and rutin content in the localities of Huatusco and Cosautlán, with elevations ranging from 1162 to 1900 m (Fig. 4). There were positive correlations between altitude (DEM) and organic matter (OM) with the phenolic compounds: quercetin, quercetin glucoside, quercetin galactose, caffeic acid, and epicatechin in the localities of Cosautlán and Melchor Ocampo, with elevations from 1162 to 1357 m (Fig. 4).

Discussion
The wild grape vines referenced grew in climates typical of the seasonal tropical forests of the Neovolcanic Axis mountains and the Sierra Madre del Sur (Gentry, 1991;Schenitzer and Bonguers, 2002).
In the four municipalities studied grew in diverse climates that include semi-humid with rain from summer to winter; semi-hot humid with summer rain; moderate temperature humid with summer rain; and moderate temperature sub-humid. The wild grape vines need tree structures to develop its canopy, and they grow during wet and dry seasons, unlike the trees, which stop growing in the dry season in tropical forests (Cai et  The altitude was after the precipitation in the driest period (Bio14), the second most important variable in the agroecological zoning model model ( Table 1) Our ndings add the states of San Luis Potosí and Puebla as potential areas for its cultivation (Fig. 4). These areas have environmental conditions similar to those in several central-southern states, with climates ranging from wet temperate with year-round rainfall, to sub-humid temperate with summer rainfall, to semi-warm with year-round rainfall, with variations of dry and warm humid climates. The physiographic characteristics of most of these include plateau, depression, mountains, and valleys, which correspond to the conditions cited by Rzedowski and Calderón (2005) for V. tiliifolia development.
The availability of water is an important environmental factor, since moderate water stress induces the production of phenolic compounds such as stilbenes and catechins (Vezzulli et al., 2007;Kounduras et al., 2007;Chaves et al., 2010;Dulec et al., 2011). High availability of water, however, implies low phenolic and anthocyanin content in the plant (Van Leeuwent et al., 2004). The phenolic content is affected not only by latitude but also by altitude (Taquichiri et al., 2014); the plants produce phenolic compounds as a stress response to ultraviolet exposure on the leaves and fruit (Del Castillo et al., 2014;Mayer and Higed, 2012). Low phenolic content has been observed in elevations above 3000 m (Berli et al., 2013); it was lowest in Atlahuilco, at elevations from 1750 to 2358 m. However, antioxidant content, including resveratrol, is greater at elevations between 1700 and 2000 m, because the leaves are with greater exposure to sunlight, and there are more photoprotective pigments and proline (Berli et al., 2013), resulting in greater antioxidant capacity.
The organic matter covariable was closely related to higher phenol content potential in the leaves. Organic matter in the soil in uences nitrogen absorption in the plant and the formation of aromatic amino acids such as phenylalanine, tyrosine, and malonates, and some of the amino acids from which the avonoids are derived (Stalikas, 2007;Orsat and Routray, 2017). In localities of the municipality of Ixtaczoquitlán (I-CGr, I-Tux, I-CCh), with altitudes ranging between 800 and 1000 m, and Huatusco Cerro Elotepec (H-CEI), organic matter was correlated with potential contents of the gallic acid, vanillic acid, chlorogenic acid, and vanillin in the leaves (Fig. 4). There were 29 municipalities in the state of Veracruz with high potential for growth and use of V. tiliifolia (Fig. 2)

Conclusions
The V. tiliifolia vines that develop at elevations between 1000 and 2000 m achieved the highest potential to produce phenolic compounds. In Veracruz, these elevations corresponded to the communities of Huatusco and Cosautlán. The map for Mexico showed that the areas with the best agroecological conditions were located in the Sierra Madre Oriental, the Neovolcanic Axis (San Luis Potosí, Hidalgo, Puebla, and Veracruz), the Sierra de Juárez (Oaxaca), the Sierra Madre del Sur (Oaxaca and Chiapas), and the Sierra de Chiapas (Chiapas), a total of 285 municipalities. The predictive variables that contributed most to the model were precipitation in the driest period, the elevation, organic matter, precipitation in the wettest period, and seasonality of precipitation.   Agroecological zoning of Vitis tiliifolia in Mexico, using the maximum entropy model Note: The designations employed and the presentation of the material on this map do not imply the expression of any opinion whatsoever on the part of Research Square concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. This map has been provided by the authors.