SUGARCANE CROP ADAPTATION TO CLIMATE CHANGE IN GUATEMALA

Mario Melgar* and José Luis Quemé**

CENGICAÑA, Guatemala

direccion@cengican.org

ABSTRACT The Intergovernmental Panel on Climate Change, IPCC, has presented scientific evidence of the influence of human activities on climate change, so that climate change will be a new challenge of countries' medium- and long-term development. This paper presents information about measures that the Guatemalan Sugar Agroindustry has been developing for adaptation to climate change on production systems in the Guatemala sugarcane area, especially in the sugarcane crop as a bioenergy source. *Director of the Guatemalan Sugarcane Research and Training Center, CENGICAÑA and Board of Directors of

the Private Institute for Climate Change Research (ICC).

**Plant Breeder, Varieties Program, CENGICAÑA

INTRODUCTION The Guatemalan Sugarcane Agroindustry occupies an important place in the economy of the country, because of this it is necessary to analyze the impacts of climate change on sugarcane crop and what adaptation activities should be developed. A review of this is what is presented in this paper. According to the report of the Bank of Guatemala, for the harvest season 2012/13 sugar accounted for 38% of traditional agricultural exports and generated 875 million in US $ in foreign currency, which are the basis for exchange economic of the country. The export earnings from sugar and molasses in 2013 ranked first in agricultural exports. In the harvest season 2012/13, were produced 26.75 million tonnes of cane and 2.8 million tonnes of sugar in 263,000 hectares equivalent to 2.5% of the national territory. The social impact of the Sugar Industry is mainly reflected in employment generation, foreign exchange and energy production: sugar, ethanol and electricity.

BIONERGY In Figure 1, it can be seen as the sugar mills in the country have collaborated in recent years to the satisfaction of the national electricity demand. In 2013, the mills contributed to the national grid 1521 GWh / year representing 15.9% of the total annual demand for the country. If this value is compared to the amount contributed by the year 2005 (725 GWh), it appears that in eight years the ability to sell the mills increased to double. The energy input from the mills to the interconnected national grid varies throughout the year. The mills deliver a higher amount at time of harvest, reaching contribution to be up 24% of the country's demand.

Energy reported as biomass is mostly generated from bagasse milled cane sugar, so these contributions are considered as energy from renewable sources (bioenergy).

Figure 1. Participation of the mills (BIOMASS) in the delivery of electricity to the SNI

Source: Informes estadísticos 2005 a 2013, Administrador del Mercado Mayorista. Guatemala.

http://www.amm.org.gt/portal/?page_id=145

It is estimated that by 2014, the sugar mills will produce 278 million liters of ethanol, which in its

majority is exported to Europe and the United States. Figure 2 shows domestic ethanol production (million liters / year) of the last five years to June 2014. Domestic consumption is not for fuel ethanol but industrial alcohol for beverage and industrial chemical processes. Ethanol production in the country is generated for five distilleries attached to sugar mills.

Figure 2. Development of production, export and domestic consumption of ethanol in Guatemala

Source: Karla Tay. 2013. Guatemala. Biofuels Annual. Update on Ethanol and Biodiesel Issues.

http://gain.fas.usda.gov/Lists/Advanced%20Search/AllItems.aspx

CLIMATE CHANGE IN GUATEMALA The global warming of our planet is caused by emissions of greenhouse gases, this natural phenomenon always occurred, however, in the last 50 years has been at an accelerated rate due to increased greenhouse gases , which has caused global climate change, rising temperatures and changing rainfall patterns. Gases contributing to the greenhouse effect are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O) and others, one of the most important in the global warming is CO2 (IPCC, 2007, National Geographic, 2014). Continued emissions of greenhouse gases will increase annual temperatures in major growing regions of

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the world, therefore, therefore, this situation means that future crop production is faced with multiple challenges of global climate change (Ainsworth and Ort, 2010). One of those challenges will be the ability of agricultural production systems to adapt to the impacts of climate change. According to Howden et al, 2007 “The strong trends in climate change already evident, the likelihood of futher changes ocurring, and the increasing scales of potential climate impacts give urgency to addressing agricultural adaptation more coherently”. Díaz, 2013 indicates that: although Guatemala contributes to less than 0.1% of the World’s emmision of greenhouse gases, our country is being seriously impacted by the climate change and variability; intensity and frequency of extreme events have increased. The GFDRR mentions that some of the major trends in the climate of Guatemala are: As with other Mesoamerican countries, Guatemala is considered a primary hot spot for climate change in the tropics. An analysis of temperature and precipitation reveals many changes in the extreme values of these variables during the period between 1961 and 2009: Maximum temperature extremes increased by 0.2°C and minimum temperatures increased by 0.3°C per decade; The number of cold days has decreased during the period December through February and the number of hot days has increased in March through May; The number of hot days and nights has increased by 2.5 and 1.7 percent per decade, respectively. Conversely the number of cold days and nights has decreased by -2.2 and -2.4 percent; Precipitation has exhibited a decrease in monthly values, with the greatest reduction seen in June and August; The number of consecutive dry days has increased and the dry season is warmer and more prolonged; Overall, the trend over the last 40 years suggests a strengthening of the hydrological and climate cycles, with more intense rain occurring across shorter periods of time that produces greater average precipitation per episode. This trend may continue in the future due to climate change, possibly resulting in a greater frequency or intensity of both floods and droughts. The climate of Guatemala will continue presenting the following trends: fewer cold days and hot days increase; increment in the number of dry days and the dry season will be longer and more intense. The intensification of heat waves will cause more droughts; it is likely an expansion of semi-arid areas due to the reduction in precipitation.

IMPACTS OF CLIMATE IN SUGARCANE CROP CANE SUGAR PRODUCTION The impact of climate change affects the entire value chain: field, harvest, transport and factory. Sugar production in Guatemala has been hit by several tropical storms in recent years, Mitch (1998), Stan (2005) and Agatha (2010), as shown in Figure 3.

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It has also been found a reduction ratio in the accumulation of sugar and the thermal amplitude mainly attributed to the increase in the minimum temperature.

ADAPTATION Ainsworth and Ort, 2010 indicate that the IPCC defined adaptation as the adjustement of agronomic practices, agricultural processes, and capital investments in response to the threats of climate change. The IPCC, 2007 defines adaptation as “Initiatives and measures to reduce the vulnerability of natural and human systems against actual or expected climate change effects, indicating that there are different types of adaptation, such as preventive and reactive, private and public, and autonomous and planned. A definition of adaptation from the agricultural point of view is describing Ainsworth and Ort, 2010, which states that adaptation is the adjustment of agricultural practices, agricultural processes, and capital investments in response to threats of change climate.

Rickards and Howden 2012, define three levels of adaptation: incremental, systems and transformational. These levels of adaptation are related to levels of climate change, ie when climate change goes of less to more, the adaptation starts with incremental adaptation, extends to system adaptation and ultimately gives transformational adaptation. The "incremental adaptation" involves making changes while maintaining the essence and integrity of systems, for example, changes in varieties, planting times, nutrient and other. The "adaptive systems" consists of changes to an existing system, eg new crops types, adoption of precision agriculture and others. The "transformational adaptation" is the most radical (in time and space) due to strong climate changes and extreme events, for example: the transformation of land use, new products and other. In this paper we review adaptation measures primarily for incremental level.

According to Howden et al, 2007 “The strong trends in climate change already evident, the likelihood of futher changes ocurring, and the increasing scales of potential climate impacts give urgency to addressing agricultural adaptation more coherently”. Stokes, 2011 proposes the following priorities for adaptation in agriculture: Information delivery from climate analyses; Plant Breeding and Biotechnology; Plant nutrition; Irrigation efficiency; Soil and water conservation methods; Biosecurity, quarantine, monitoring, and control measures; Better models of agricultural systems; Monitoring and evaluation systems; Policy and management decisions Specifically for sugarcane, an important reference is “Adapting agriculture to climate change for sugarcane” by Park et al., (2010)

SUGARCANE CROP ADAPTATION TO CLIMATE CHANGE IN GUATEMALA

According to the definition of adaptation of the IPCC 2007, the Guatemalan Sugarcane Agroindustry is implementing an adaptation that is characterized as private, preventive, reactive and is starting a planned adaptation, which consists in the knowledge of the conditions that have changed or are changing and the requirements needed for adaptation to climate change. Considering the levels of adaptation described by Rickards and Howden, 2012, an important example of "system adaptation" is the substitution of cotton cultivation by sugarcane. According to Gil, 2006, cotton cultivation began in the mid-twentieth century and had its heyday in the 70's, beginning its decline in the early 80's. Among the factors that contributed to this decline may be mentioned the following: lack of adaptation to local climatic conditions, lack of research and excessive use of pesticides. Cotton cultivation was replaced mainly sugarcane, which gradually increased its area, as seen in Figure 3. Maybe, if they had done research with a focus on "incremental adaptation," cotton cultivation had not lost its importance. During different years of observation, sugarcane has absorbed climatic changes with low negative effects on production, therefore, can be described as a resilient crop. This goodness of sugarcane has helped to extend its area to places with limited production system and hostile environments. Different adaptation strategies are described below; most are "incremental adaptation" and consist in an improvement or extension of activities that are already being developed by the canegrowers, the sugar mills, tha Guatemalan Sugarcane Research and Training Center, CENGICAÑA or the Private Institute for Climate Change Research, ICC.

Weather information system and climate analysis Guatemalan Sugarcane Agroindustry has a network of 20 automatic weather stations, based on this it has been developed a meteorological information system that displays weather variables in real time and analyze the temporal and spatial climate information. The ICC issued bulletins: weather, El Niño and water balance. The analysis of climate information allows to study the effects of phenomena such as ENSO (El Niño Southern Oscillation) and climate change. Castro and Suárex, 2012 have been described the effects of ENSO on the energy balance, hydro balance and the sugar accumulation.

Through agrometeorological studies have found the relation of various climatic variables with the production of sugarcane, such as solar sunshine of August that is highly correlated with the production of sugar cane as shown in Figure 4.

Through these analysis general forecasts has been developed for sugarcane production.

Figure 4. Relationship ENSO, August sunshine and tonnes of cane per hectare (TCH) of the

Guatemalan Sugarcane Agroindustry. CENGICAÑA 2012.

Castro and Suárez, 2012 have been reported a relation between sugar yield and termal amplitud, indicating that in the period 2006-07 to 2010-11 sugar yields and thermal amplitudes have been low in terms of the minimum temperature has increased. The low thermal amplitude in function of the high minimum temperatures is one of the factors that may help explain the low yields of sugar. The ICC has developed a climatic regionalization of the Pacific slope and indeces of climate change (ICC, 2014). The study showed that indices of climate variability related to temperature showing a tendency to increase are: extreme high temperature, number of summer days and warm evenings frequency. In the case of precipitation-related indices, which tend to increase as the number of consecutive days with precipitation greater than 10 mm and the number of consecutive dry days. Towards the future should strengthen the Climate Forecast System to support decision-making on technical, environmental and market aspects. So it will be important to implement Eco Physiological models to quantify the potential impacts of climate change in terms of crop yield and to evaluate the effectiveness of adaptation strategies, as mentioned Park, 2008.

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Breeding Several authors (Basso et. al., 2013; Da Silva et al,. 2008; FAO, 2013; Park,2010; Santos, 2008; Viveros, 2011) agree that a very important activity for adaptation to climate change will be developing new varieties to drought tolerance, efficient to water use and varieties for higher temperatures.

The Variety Program of CENGICAÑA has a breeding strategy aimed at increasing the yield potential of sugarcane and improves adaptation to climate change. The strategy is based on four major processes: 1) genetic resource, 2) crossings, 3) selection and 4) development of varieties. Genetic resources : to increase genetic variability, CENGICAÑA s Varieties Program has a National Collection of 2,040 accessions or varieties from different countries and continents. It is an ongoing program activity to increase National Collection importing new varieties and incorporating CG (CENGICAÑA-Guatemala) varieties that have come to regional trials (Orozco et al., 2012The varieties that are imported are entered into a quarantine system in order to minimize the risk of introducing pathogens. In the quarantine, besides the phenotypic evaluation of symptoms, has been implemented for the molecular detection of major bacterial or viral diseases. Plant tissue culture is used to cleaning of introduced varieties, this prevents the transmission of diseases, pests, and pathogens. The conservation of genetic resources is carried out in the field, replicated at two locations in Guatemala sugarcane area. This collection is evaluated every year, data related to yield components, sugar, diseases and other are recorded. We are currently implementing the registration of the wax on the stems, as this helps to save water by not allowing the loss by heat (Viveros, 2011). In the medium-term will plan to incorporate the record of other features related to water stress and water use efficiency. The importance of the evaluation of the National Collection is determining the performance of the accessions in different locations and across several years, which allows to identifying accessions with good response to climate variations. Crosses: the crosses are made between parents who permit an offspring with specific characteristics such as: yield of cane and sugar, fiber, disease and pest resistance, adaptability over time and space, and other agronomic traits. The source of the parents is the National Collection, recent varieties (Saccharum spp hybrids) and original varieties associated with different species of Saccharum are used, thus taking advantage of the variability in the Collection. Sexual seeds obtained from crosses gives raise a population of seedlings, which are subject to the selection process. Selection: this process consists of five stages of selection through 11 years, starting in the stage I with an abundant population of seedlings and ending in the stage V (semi-commercial test) with few varieties evaluated. The state IV corresponds to the Regional Yield Trials, where varieties are evaluated in contrasting environments (soils, rainfall, handling and other). In this way, future varieties are screened across locations and years, thus allowing to observing the performance of the varieties under conditions of climatic variation over a period of 11 years To improve the selection process in the stage I, Familial Selection Method has been implemented. The benefits of the implementation of this method are reported by Quemé et al., 2013 as follows: 1) the implementation of the familal selection to the selection process of the Stage I is beneficial to obtain the expected progress of hybridization and selection, achieving ensure obtaining superior varieties, 2) the familial selection is a tool oriented in two directions: a) to identify parents and superior crosses and b) in the most efficient selection, and 3) establishment of individual clonal familial selection in commercial production environments relevant to the Sugar Industry, decreasing the effect of interaction genotype by environment.

Throughout the selection process, the variables recorded are: sucrose content, fiber, disease resistance; emergency, regrowth, stalks population, height and diameter of stalk; lodging, flowering, cork, natural maturation; leaf coverage and others. The selection is made by considering all variables simultaneously according to selection criteria. Each of these variables can be influenced by climate change, therefore, the varieties that meet appropriate expressions for these variables can be considered to as varieties adapted to climate change. It is looking to obtain varieties with good adaptation, efficient use of water and nutrients; and that these contribute to reducing the use of agrochemicals. To analyze the phenotypic plasticity and genotype by environment interaction, Variety Program in the stage IV of selection develops multi- environments yield trials considering the agro-ecological zoning for sugarcane area. The data are analyzed with statistical models of genotype x environment interaction in order to identify high-yielding varieties with broad or specific adaptation in the space and broad adaptation over time. Development of varieties : in this process, the breeder and producers define the most suitable varietal composition and monitoring is planned. The goal is to plant in each agro-ecological zone the most adapted varieties, high yield (cane and sugar); resistance to disease, appropriate agronomic characteristics and others. A good example of research to develop varieties for future climate conditions is described by Stokes, 2013, in the "Climate Ready Sugarcane: Traits for Adaptation to High CO2 Levels" project. Research is needed on Sugarcane Physiology related to the increase of CO2, temperature increase, resistance to moisture stress and improvement of photosynthetic activity (Parks, et al., 2010, Da Silva 2008, Stokes, 2013)

Biotechnology Biotechnology activities in CENGICAÑA are aimed at the molecular characterization of progenitors, detection molecular of diseases, tissue culture for cleaning introduced varieties when these are infected with diseases, marker assisted selection and studies of transgenic plants. In the molecular characterization of parents, genetic relationships between them are determined; this is useful in planning crosses. The detection of disease and tissue culture has improved the quarantine process, avoiding the introduction of diseases, and clean infected varieties. In marker assisted selection have been done studies related to the marker of Brown Rust (Puccinia melanocephala) associated with Bru1, finding high coincidence of genotypic and phenotypic resistance, therefore, it is starting the use of this marker for marker assisted selection. As it relates to transgenic plants, studies are being initiated with the purpose of providing medium and long term crops adapted to climate change. This is: resistant crops to pests and diseases, abiotic stress tolerant crops like: drought tolerant crops, low temperature or salinity, also to improve biological nitrogen fixation and accelerate traditional breeding processes. In sugarcane, Molina, 2012 reported that transgenic characteristics on which there are worldwide progresses are resistance to insects, diseases and abiotic stress (water deficit, high temperature and salinity). EMBRAPA Brazil (CropBiotech Update, 2011) and The Indonesian Sugarcane Reseach Center (Lubis, 2013) have indicated that they have developed a drought-resistant transgenic sugarcane variety.

Fertilization Robertson, 2012 indicates that the production of nitrous oxide can be reduced if the amount of fertilizer applied to the crop is exactly the amount it needs. Pérez, 2012 has developed nitrogen (N) dose recommendations for Sugarcane crop in Guatemala according to soil type, variety, crop cycle (plant cane and first ratoon), irrigation, level of soil organic matter, the expected return; and the time and method of application. Varieties play an important role in the recommendations of N, since, it has been determined that there are differential requirements of the varieties regarding N (kg N / t of cane). The recommendations are "variable" instead of "generalized", therefore, there has been a reduction in the dose of N, mainly in plant cane. There has been research related to biological Nitrogen fixation (BNF). In looking and exploitation of the potential of specialized bacteria that use N of air that superior plants as sugarcane cannot take advantage, getting to identify sugarcane varieties able to obtain large and significant amounts of N by the pathway of BNF. It has also been determined the contributions of nitrogen that green manure (Crotalaria juncea, Canavalia ensiformis) can generate and the potential of biological nitrogen fixation.

Efficient use of water With the increase of temperature and drought risk, the efficient use of water is an indispensable strategy for adaptation. CENGICAÑA s Department of Irrigation s general objective is optimization of water use seeking technical and economic efficiency of irrigation and irrigation methods. Castro, 2014 describes the key technologies that have been adopted in the sugarcane area of Guatemala: 1) Irrigation planning using climate-ocean parameters, soil, sugarcane; 2) more efficient irrigation systems and micro sprinkler, center pivot and drip; 3) Use of hydrobalance; 4) Study of groundwater levels and analysis of the capillary supply; 5) Efficiency in water conduction. These technologies have allowed irrigate more area with less water, as demonstrated in the results of the harvest season of 1990/91, where it was irrigated 0.88 ha per megalitre of water (ML), while in the harvest season 2012-13 was irrigated 1.42 ha / ML. The goal in the short and medium term is to continue to minimize water use, but without neglecting cane production.

Water storage Guatemala has markedly two seasons: With rain (May-October) and no rain (November to April), so the water storage will be a necessary adaptation strategy, as there is water deficit in short (canícula) and long (seasons without rain) periods. Chan, 2012 mentions that the ICC is devoting efforts to the research of methods to capture and store water, starting with a review of the methods of water storage in the world, and then propose applications for the sugar cane area of Guatemala.

Integrated Pest Management (IPM) Márquez, 2012 describes the pests that have historically caused more economic damage to the cultivation of sugarcane in Guatemala.

Since 2005, with increasing temperature, new pests have begun to cause some economic impact on the crop. The strategy of integrated pest management is also important as an adaptation activity. IPM focuses on the rational implementation of appropriate techniques, such as: chemical, cultural, physical, technical and ethological type, with greater emphasis on biological strategies in a sequence consistent with the bio-ecology of the pest and environmental care. It has been generated: loss values, damage indices and

economic threshold for major pests, which serve as decision support and control programs in each pest. IPM aims to control pests and reduce or eliminate the use of pesticides

Monitoring and evaluation systems For monitoring and evaluation of the sugarcane area CENGICAÑA has developed the following tools: The Climate Information System, SIM, to visualize climate variables in real time and display climate information in time and space (CENGICAÑA, 2012); Agroecological Zoning, ZAE, of the guatemalan sugarcane zone obtained of interaction of two geographic layers corresponding to Soil Management Groups and Hydro iso-balance group. The agro-ecological zoning is currently being used to analyze the results of the harvest season, for comparative studies of productivity between sugar mills, for the proper location of regional and semicommercial varieties trials and extrapolation of research results and to relate management variables (CENGICAÑA, 2013); Agronomic Management by Plot Approach, MAPA, (Villatoro, 2014): it is a system of agronomic information by plot, using the principles of precision agriculture. The database includes geographic information, productivity, varieties, agronomic management and pests; Productivity Analysis System integrates and reports information of productivity and factors of production weekly during the harvest season; Annual Symposia of Harvest Season Analysis organized since 1996 to compare productivity, efficiency and best practices in Field, Factory, Transportation and Cogeneration. With this activity promote benchmarking processes.

CONCLUSIONS Sugarcane crop is very important in Guatemala in generating employment, foreign exchange and the main source of bioenergy. Although Guatemala contributes to less tran 0.1% of the World s emmision of greenhouse gases, it is considered within the highest risk to the impacts of climate change (temperature increase, droughts, storms, floods, landslides). In agriculture in general and sugarcane should develop practices to adapt to climate change according to the vulnerability of the systems and the level of climate change. Depending on the magnitude and level of climate change; and the benefits and costs of adaptation; should be implemented adaptations “incremental", "systems" and "transformational". The incremental level priorities include: Climatological information system, breeding, quarantine, biotechnology, fertilization, efficient water use, water storage, Integrated Pest Management and Monitoring and Evaluation Systems. Although it has been observed that the sugar cane is one of the most resilient crop to climate conditions in the South Coast of Guatemala, Sugar Agroindustry is developing a planned adaptation.

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