Sample size

Sample size was estimated with a random stratified sampling with proportional distribution, accuracy of 10% and 95% confidence (Taro, 1967). The sampling units were producers arranged in two strata according to the number of planted hectares per producer, so that the stratum K₁ was integrated by producers with a half up to five planted hectares and stratum K₂ of more than five hectares (Table 1). The sample size was calculated with the following equations:

Table 1 Population elements and sample size by stratum. 

The information was collected through a questionnaire with a semi-structured script. Data were tabulated and analyzed using the predictive analytical software and solut (PASS) version 21 statistical package. There were used as a dependent variable (sown area, producer’s age, number of economic dependents, number of years knowing the seed) and independent (stratum) in order to calculate Levene’s test for variance homogeneity and to contrast the hypothesis H₀:σ1²= σ2²= σ3². In addition, the means comparison was performed using one-way ANOVA and to contrast the hypothesis H_0:µ₁= µ₂= µ₃ and find significant differences per stratum (^{Perez, 2009}; ^{Nel, 2012}).

With the data obtained from the questionnaire generated an indicator with values from 1 to 0.2 to evaluate the level of adoption of the seed technology component, was generated. This indicator considered that, if during a period of five years a farmer sows INIFAP’s seeds, there has been an adoption. To do so there were considered the years of seed use, the satisfaction degree of the obtained products, the agronomic advantages of the seed and its availability in the market. The indicator took a one value when the producer sowed the seed uninterruptedly. The value was 0.8 for farmers who during the five-year period sowed the seed in a fickle manner or are disrupting the adoption process. The indicator value varied from 0.4 to 0.6 depending on the number of years planting the seeds. The lowest level was 0.2 for the farmer who is initiating the adoption process, or that tested the seed and did not like it, so adoption was considered an unlikely process.

With this indicator, producers were typified into three categories: a) they knew it and adopted it; b) they knew it and started the adoption process but interrupted it; and c) they knew it but did not adopt it.

Characteristics of maize farmers

Sociodemographic characteristics of respondents indicate that 95.5% has lived all their life in the locality, all were married men, with an average age of 54 years, no significant difference was shown at the Levene statistic (p= 0.209) for the variance homogeneity test and Anova (p= 0.273), because critical levels were calculated above 0.05. 56.2% of respondents have mainly primary studies (5.3 years), characteristic schooling of maize producers for the studied area (^{Uzcanga et al.., 2015}). Likewise, there was no statistical difference between the number of economic dependents per stratum, which stood at 3.3 persons on average (Table 2).

Table 2 Characteristics of the producers sample. 

^*Límite del intervalo de confianza para la media al 95%.

64.8% of the sample’s producers have maize as a main crop and 35.2% is engaged in some other activity in the agricultural sector: beekeeping, livestock and sowing other crops such as pineapple, sugar cane and henequen; there were also identified, albeit to a lesser extent, trades such as masonry, local transporters and employees of some business.

The production is marketed mainly in regional markets or locally placed in mills or among their neighbors as food for their animals.Another 38.2% of both agricultural and livestock producers produce maize mainly for their own consumption (Figure 2).

Figure 2 Main occupation of the sample of producers. 

Typification of farmers by category

Over a period of approximately 51 years (1964-2015) farmers in the study area reported being familiar with improved maize seeds. This boom in the knowledge of this type of seed occurred from 1997 to 2007 and from 2008 to 2015, periods that registered the highest frequency among farmers and coinciding with the period (1999 to 2010) of increased supply and demand of hybrids generated by INIFAP from 20 different crosses and parental lines (^{Larqué et al.., 2013}).

On the other hand, among farmers of stratum K₁ and K₂ differences to establish an average and indicate how long since known improved seeds were found. For farmers of K₁ stratum the average was 7 years, whereas for farmers of K₂ stratum the average was 12 years. The majority agreed (34.3%), knowing the seed by a friend or family member who told them about it, (17.1%) by the technician of the Ministry of Agriculture Livestock Fisheries and Food (SAGARPA), in some demonstrating plot of another producer (13.3%), among the most significant.

Although respondents prefer to use improved seeds, it was identified that 53.8% of them did not know free pollinated varieties, improved native and hybrids from the INIFAP and for this reason they have never planted them, mainly farmers of the K₁ stratum (31.4%) and with a lower percentage those from K₂ (22.4%). The rest of the farmers (46.2%) reported knowing them, of which 33.3% have cultivated some variety, among which are the H-520 and VS-536, materials that adapt to the conditions of the Yucatán Península (Table 3).

Table 3. Maize varieties released and registered by INIFAP and identified by farmers. 

The results indicated that 16.7% of the farmers started the adoption process but at some point during the five years of evaluation they stopped using it, while another 12.9% said they knew the materials but had never cultivated them and only 7.1% have adopted varieties (Figure 3).

Figure 3 Scheme of preferences of INIFAP’s seeds from the farmers of the sample. 

When asked the reasons why they no longer continued planting, anwers was because there is not availability of seeds in the market and ignorance of how and where? to buy them and its yield benefits, which motivates the interest to try other improved seeds by another institution or company. In this sense ^{Flores and García (2016)} emphasize that the adoption of improved seeds implies a cost and that the lack of knowledge about the possible benefits in yield is a determining factor when adopting the technology or not.

There are studies such as those presented by Kafle (2010), where they establish that the factors that determine the adoption of improved seeds are socio-economic. These results are reinforced by various authors in different conditions such as the case of Zambia presented by ^{Kalinda et al.. (2014)} where they conclude that the adoption of improved seeds showed a positive relation with the size of the farm or that for estates rented or greater than one hectare, farmers prefer to invest in improved seed with the whole technological package to ensure the yields (^{Sserunkuuma, 2005}).

In Mexico, the states of Baja California and Sonora report the highest adoption of improved materials, but their agricultural areas are greater than 12 ha (^{García and Ramírez, 2012}). Another factor that is involved in the adoption of these technologies is the poverty level in the region (^{Bernard et al.., 2010}) which affects producer income which is another determining factor in the adoption rate (^{Flores and García, 2016}).

Another factor that influences the preference for certain maize, is related to its final use, for the production of fresh dough and tortillas, the demand is for white maize (56.2%) and to a lesser extent for yellow (37.1%), purple (3.4%), red (2.2%) and tinted (1.1%).

This preference detected in the Yucatán Península is valid for all Mexico (^{Coutiño et al.., 2008}). For example, the genotypes H-563, H-520 and VS-536 identified by the farmers of the Península, are white-grained and have physical characteristics of nixtamalera quality suitable for the dough and tortilla industry. The first is from Guerrero and the other two are from Veracruz and in general, commercial white maize released into areas of the humid tropics are suitable for this industry (^{Salinas et al.., 2010}).

However, although improved varieties have shown to be superior to native ones, there are other factors such as purchasing power and crop extension that influence the preference of small farmers over local varieties. In addition the added value on tradition, that these genetic materials have been developed by farmers through multiple cycles of empirical selection and preserved and handled under a scheme of traditional agriculture as a complex system of seeds (^{Aragón et al.., 2006}; ^{Gaytan et al.., 2013}).

The research identified that 83.8% of the sampled farmers have once sown native breeds, among which Dzit-bacal stands out (Figure 4).

Figure 4 Scheme of preferences of INIFAP’s seeds from the farmers of the sample. 

These landraces have a wide variety of applications as indicated by Narvaez-González et al.. (2007), who have identified at least three uses, for example Dizt-bacal is used for tortillas, snacks, the Tuxpeño in addition to the preparation of tortillas and other related products is also used for the elaboration of atoles and beverages such as pozol just like the Olotillo and Tepecintle (^{Fernández et al.., 2013}) (Figure 5).

Figure 5 Scheme of preferences of INIFAP’s seeds from the farmers of the sample. 

The quality criteria reported for common uses of maize indicate that outstanding landraces for making tortillas are Tuxpeno and Olotillo for having hard or semi hard grains, and other well suitable features for this purpose (^{Fernández et al.., 2013}).

Additionally, the preference for these landraces is influenced by the advantages showed to suit edafo-climatically- limited land (^{Turrent et al.., 2012}). In addition to adaptation and stability to local climatic conditions, therefore low demand for agricultural labor by reducing labor costs and inputs needed for production (^{Fernández et al.., 2013}).

In this regard, some agronomic advantages were identified by farmers by type of seed used, standing out the yield for improved varieties, longer shelf life and greater tolerance to drought for native breeds (Table 4).

Table 4 Agronomic advantages by type of seed according to the farmer’s opinion. 

Attitude of the farmer to technological innovations

The work model used by INIFAP comprises four stages: 1) experimentation: in which the knowledge that supports the technology is generated; 2) validation: a process in which the applicability of research results in the commercial context is evaluated; 3) transfer: activity that is carried out with the diffusion of the technological innovations to the users; and 4) adoption: defined by the incorporation of the technological component into the production system (^{Laird, 1977}).

Authors such as ^{Rogers and Svenning (1979)}, indicate that the spirit of innovation, understood by the degree of anticipation with which the individual adopts new ideas with respect to other members of the community, is essential for the adoption of a technological innovation, where diffusion has an important role.

In this sense, it was identified that 47.1% of the farmers in the sample know what do some of the agricultural research institutions do such as the Autonomous University of Chapingo, Postgraduate College, CIMMYT and INIFAP, of these, 86.9% consider that what they do is useful, but only 40% of the total number of producers in the sample seeks the means to be informed about the technological innovations with respect to their crops.

Since the decision to innovate is taken by each individual and the adoption rate is estimated by the proportion of individuals accepting the innovation in a given period, it could be assumed that the adoption rate of INIFAP’s improved seed, during the last five years for the Yucatán Península, was 7.1%. Which is a low percentage explained by the heterogeneous demand for improved seeds in rainfed areas and therefore the adoption of these materials is uncertain (Donnet, 2012).

One of the reasons why the adoption of improved seeds has been very slow by farmers, is due according to ^{Guillen et al.. (2002)}, to the producer’s perception of the benefits of native breeds beyond yield, since hybrids are commonly associated with limited gains versus their high technological package costs. In addition, the size of the farm and the income per hectare are the main factors for the adoption of improved seeds (^{García-Salazar and Guzmán-Soria, 2015}).

Although the use of improved seeds has increased over the past 15 years, the adoption pattern has been patchy and its use has been concentrated in areas of commercial production such as the northeast and El Bajío (^{García and Ramírez, 2014}).