In Mexico, bean is a crop of great importance as a basic food grain and an excellent source of protein (containing 20 to 25%, of which 3% are tryptophan of high quality), vitamins such as thiamin, niacin and folic acid and minerals such as iron (^{Guzmán-Maldonado et al., 2002}; Ulloa et al., 2011). During 2014, 1 773 996 has of this legume were sown, obtaining 1 273 957 t grain from different commercial classes (^{SAGARPA, 2015}).

In the same year, in the state of Chiapas were established 116 575 ha, producing 61 412 t, being 85% black bean, 10% red bean and the rest other types of beans (^{SAGARPA, 2015}). The red bean red is sown in production units of one hectare or less, located in areas with climate Aw, warm humid with rain in summer (^{García, 1981}), located mainly in the municipalities of la meseta comiteca and la Frailesca, and whose production it is mainly used to meet the needs of local consumers (^{Rodríguez-Licea, 2010}; ^{Villar et al., 2011}). In recent years, the demand for this type of grain has increased from 6 248 t currently produced to over 8 000 t to meet it must grow about 15 000 ha, for the temporary or permanent establishment of an increasing number of Central American immigrants in the entity, with consumption preference for red bean (^{Villar et al., 2010}); this represents an opportunity to increase acreage, and even to export to Honduras, Nicaragua and El Salvador, and to the United States of America, where inhabitants from these Central American countries live (^{Paz et al., 2007}).

Currently, red vean sowings are made with creole materials of low yield potential, very specific adaptation and susceptible to diseases like yellow golden mosaic and poor adaptation in acid soils of low fertility from the state of Chiapas (^{Villar et al., 2011}). In the Bean Program from the National Institute of Forestry, Agriculture and Livestock (INIFAP) for the southeast of Mexico, have been performing studies to evaluate lines introduced from Central America, red bean lines, which has allowed to identify outstanding materials in terms of yield, adaptation and grain type that consumers demand; in this way Sangre Maya variety was generated for tropical areas from the state of Chiapas (^{Villar- Sánchez et al., 2013}).

This variety originated from a triple cross (NCB 228 x RCB 224) F1 x SXB 244, performed at the International Center for Tropical Agriculture (CIAT) in Cali, Colombia and obtained by gametic selection (individual plant) in F1, to create only one family derived from F1 and then continued with F2 selection under drought conditions at CIAT-Palmira, Colombia. The F3 was established in Popayan, Colombia, where plants were inoculated with the fungus (Colletotrichum lindemutianum) (Sacc. & Magn.) Scrib., which causes anthracnose disease and resistant individual plants were collected. F4 was sown in Santander de Quilichao, Colombia, in acidic soil, with moderate stress of low phosphorus and inoculated with the fungus (Phaeoisariopsis griseola) (Sacc.) Ferraris, causing angular leaf spot disease. F5 was planted in Palmira, Colombia, to quantify yield under drought, and a single plant was selected to obtain a uniform F6. The line from which the variety Sangre Maya was generated, was introduced to Mexico in 2009 and to the state of Chiapas in 2010, with the code RCB 592 through a uniform trial of yield, which was conducted in different locations in Chiapas from 2010 to 2012, in order to determine their yield response, disease resistance and adaptation to acid soils of low fertility (^{Villar et al., 2013}).

Among the main agricultural characteristics of Sangre Maya are the following: indeterminate growth habit, with intermediate length vines and shrubs, erect and compact type II (^{Singh, 1982}), with small leaves and a height of its average canopy of 48.5 cm. Flowering occurs on average at 38 days after sowing and physiological maturity at 70 days. Its flowers are white, the stem is green and pods are white in physiological maturity and creamy white to harvest, with small grains, red, opaque and ovoid. Among the most outstanding characteristics of this variety are its resistance to disease bean golden yellow mosaic virus (BGYMV), adaptation to acid soils from the humid tropics of Chiapas and its earliness, which allows it to adapt to intermittent drought under rainfed cicle and ends in the residual moisture cycle (^{Villar- Sánchez et al., 2013}).

From 2010 to 2012, Sangre Maya was compared with the variety Bribri and Creole Coloradito in a uniform yield trial conducted in nine environments from the state of Chiapas, under rainfed, residual moisture and irrigation conditions. The new variety outperformed the commercial controls. Under rainfed conditions, Sangre Maya exceeded 12.9% the yield from Bribri and by 56.2% to Creole Coloradito. Under residual moisture the percentages of superiority of the new variety were 3.2 and 19.8%, while under irrigation, were 5.6 and 28.8%, respectively. The overall average yield of Sangre Maya was 9.0 and 40.4% higher than Bribri and Creole Coloradito (Table 1). These results show the higher yield potential, that the new variety has regarding to Creole coloradito, commonly used by farmers in the state of Chiapas (^{Villar-Sánchez et al., 2013}).

Under the rainfed cycle from 2012 in the town of Emiliano Zapata, municipality of Villaflores, Chiapas, intermittent drought conditions and temperatures above 30 °C, favored the presence of high populations of whitefly (Bemisia tabaco Gennadius) causing bean golden yellow mosaic virus (BGYMV). During the beginning of the reproductive stage of the crop (35 days after planting), the reaction of Sangre Maya, Creole Coloradito and Bribri were evaluated to meausere the incidence of this disease (^{CIAT, 1987}), which reduces significantly grain yield, especially when it occurs during the vegetative stage of the crop (^{López et al., 2003}; ^{Villar et al., 2003}).

The new variety had a lower incidence to 10% and grain yield of 521 kg ha^-1, while Bribri and Creole Coloradito showed incidence of 30 and 64%, with grain yields of 267 and 322 kg ha^-1, respectively. These results indicate that Sangre Maya is a good alternative to reduce production risks by BGYMV incidence in the state of Chiapas (^{López et al., 2002}).

In the state of Chiapas, some bean producing areas have the problem of acid soils with pH and base saturation, lower than 5 and 30%, respectively, thus aluminum saturation higher than 20%, limiting grain production (^{Buerkert, 1989}; ^{Zetina et al., 2002}; ^{Tosquy et al., 2008}). In the rainfed from 2012, Sangre Maya, was evaluated along with the same controls, under acidic soil with a pH of 4 and aluminum saturation of 20% in the locality of Emiliano Zapata, with and without application of 1 t ha^-1 of agricultural lime (^{Buerkert et al., 1990}; ^{Villar et al., 2003}).

The new variety showed the best response in grain yield under both conditions of soil management; with lime, Sangre Maya obtained a yield 11.9 and 29.1%, higher than those obtained by Bribri and Creole Coloradito, respectively, whereas with acidic soil stress, the new variety exceded in 21.8 and 61%, the yield from the control. The lower percentage of yield decrement of Sangre Maya, is indicative that this variety has better adaptation to central acid soils from central Chiapas, than the variety Bribri and Creole Coloradito (Table 2).

Sangre Maya variety adapts to tropical areas from the state of Chiapas, at altitudes ranging from 0 to 1 200 m, as in the case of the region called Meseta Comiteca. It can be sown in the summer cycle, under rainfed, in fall-winter with residual moisture and in winter-spring under irrigation conditions, which ensures the availability of a water lamina of about 400 mm and an average annual temperature between 24 and 26 °C (^{Lopez et al., 2002}).