Funding this study was performed within the project ‘Asistencia técnica a 15 municipios y 2 departamentos de la region de Montes de María para la formulación de programas de inversión para el desarrollo rural’ under the Land and rural development program by the United states Agency for international development – UsAid, through the subcontract signed between this program and the observatorio del Caribe Colombiano. ar tí cu lo s de in ve st ig ac ió n

Improved P and K nutrition can enhance yield and persistence of alfalfa (Medicago sativa L.) grown on low fertility soils, but it is unknown if the improved agronomic performance is associated with greater taproot N and C reserves. Our objective was to use cluster analysis to determine how alfalfa plant persistence is altered by P and K fertilization, and determine if changes in specific taproot C and/or N reserves were associated with alfalfa plant death. Taproots were dug and plants counted in May and December of each year and taproots analyzed for P, K, starch, sugar, amino-N, and soluble protein. K-means clustering was used to create six clusters that were subsequently compared using two-sample t-tests. Low K in herbage and taproots was associated with low yield and poor persistence of the Low and Very Low clusters and taproots of these plants generally had low starch, protein, and amino-N concentrations. Plants died primarily between May and December. Plant persistence of the low yielding, P-deficient Medium cluster was high and associated with high starch concentrations. Low amino-N concentrations in taproots may provide an early indication of potential plant death because these were evident in poor-persisting Low and Very Low clusters early in the study.

Sugarcane yellow leaf disease caused by Sugarcane yellow leaf virus (SCYLV) was spread over the world through infected germplasm. This study was conducted in order to determine the presence of SCYLV in commercial fields and germplasm collection and study the genetic diversity of the virus in Cuba. Leaf samples were collected from commercial cultivars in eight provinces and the Cuban germplasm collection in Matanzas province. The diagnosis of SCYLV was performed using tissue-blot immunoassay and reverse transcription polymerase chain reaction (RT-PCR). Our results revealed the widespread incidence of SCYLV in commercial sugarcane plantations in Cuba. The coat protein sequence analyses of SCYLV isolates under study confirmed the presence of BRA-PER, CUB and REU genotypes. The REU genotype is reported first time in Cuba. Coinfections of SCYLV genotypes (BRA-PER + CUB, BRA-PER + REU and CUB + REU) were also reported. The most predominating SCYLV genotypes reported in Cuba were identified as CUB and BRA-PER.

This work aimed to identify the social and cultural perceptions regarding food security and health in the departments of Bolivar and La Guajira, in the Colombian Caribbean region. As a result, poverty and illiteracy were transversal conditions affecting food security and health of researched communities in both departments. Food security conditions are affected by external factors (low income, location, and natural resources availability). Distrust of public health institutions was a dominant factor. Thus, there is a strong need for public policies with a territorial approach to promote local food production, capacity development, and transfer of knowledge and to improve the public health service.

Sugarcane mosaic resistance is established as a key criterion for the breeding program in Cuba. However, molecular characterization of Sugarcane mosaic virus (SCMV) strains occurring in Cuba has not been reported so far. Leaf samples from commercial sugarcane cultivars were collected for SCMV screening in three testing sites (the Matanzas, Camagüey and Holguin provinces). Reverse-Transcriptase polymerase chain reaction was used to identify the virus. The nucleotide sequence comparison grouped the isolates into SCMV subgroups. Sugarcane cultivars inoculated with SCMV from three testing sites displayed different symptoms. Results should be decisive to generate the highest selection pressure, increasing the efficiency of the sugarcane breeding program to the SCMV resistance in the commercial cultivars.

RESUMEN In Cesar, 30.7% of children under 5 years of age suffer from deficiencies of vitamin A, along with 13.4% for iron and 57.0% for zinc. Therefore, it is important to guarantee food security in the population through improvements in the nutritional quality of the offered food products. One alternative is the implementation of nutritionally improved crops. The production and consumption of four basic crops in the rural areas of five municipalities were characterized and compared to the implementation of the studied biofortified crops. Surveys regarding the purchase, consumption and production of cassava, bean, maize and rice were given to those responsible for food preparation and/or agricultural production in 90 families and was determined for these food ration consumed per person. In the week prior to the survey, 95.6% of the families consumed bean, 93.3% maize and 88.9% cassava and rice. The products mainly originated from purchases in the local store (bean and rice) or grown by the families (cassava). Cassava and maize were most commonly cultivated (71.1%), followed by bean (56.7%), maize (32.1%), and rice (2.2%). A 61.6% of the cultivated cassava, 23.5% of the maize, and 26.4% of the bean were destined for self-consumption, while the rest was sold or traded. Looking at the difference between the nutritional content of the biofortified products and the traditional and eating habits indicated that the substitution of the traditional varieties with the biofortified crops represented a possible intake increase of 44.59 mg/ person-day of iron, 24.05 mg/person-day of zinc, and 1.62 mg/ person-day of vitamin A. The substitution with and exclusive consumption of biofortified crops would contribute 199, 169, and 77% iron, zinc, and vitamin A based on the estimated average requirement. Due to their potential nutritional impact, the study of the adaptability and acceptability of biofortified crops is recommended.

In Cesar, 30.7% of children under 5 years of age suffer from deficiencies of vitamin A, along with 13.4% for iron and 57.0% for zinc. Therefore, it is important to guarantee food security in the population through improvements in the nutritional quality of the offered food products. One alternative is the implementation of nutritionally improved crops. The production and consumption of four basic crops in the rural areas of five municipalities were characterized and compared to the implementation of the studied biofortified crops. Surveys regarding the purchase, consumption and production of cassava, bean, maize and rice were given to those responsible for food preparation and/or agricultural production in 90 families and was determined for these food ration consumed per person. In the week prior to the survey, 95.6% of the families consumed bean, 93.3% maize and 88.9% cassava and rice. The products mainly originated from purchases in the local store (bean and rice) or grown by the families (cassava). Cassava and maize were most commonly cultivated (71.1%), followed by bean (56.7%), maize (32.1%), and rice (2.2%). A 61.6% of the cultivated cassava, 23.5% of the maize, and 26.4% of the bean were destined for self-consumption, while the rest was sold or traded. Looking at the difference between the nutritional content of the biofortified products and the traditional and eating habits indicated that the substitution of the traditional varieties with the biofortified crops represented a possible intake increase of 44.59 mg/ person-day of iron, 24.05 mg/person-day of zinc, and 1.62 mg/ person-day of vitamin A. The substitution with and exclusive consumption of biofortified crops would contribute 199, 169, and 77% iron, zinc, and vitamin A based on the estimated average requirement. Due to their potential nutritional impact, the study of the adaptability and acceptability of biofortified crops is recommended.

The sustainable expansion of bean cultivations requires technologies that do not limit their phyto-recovering properties. Therefore, the objective of this study was to propose agronomic management of conservation for bean cultivation considering the microbiological characteristics of two mega-environments of the Colombian Caribbean coast and the compatibility between agrochemicals and bioinputs. The methodology included rhizospheric microbe population counts, identification of phytopathogenic fungi in plant tissues and soils, compatibility studies of pesticides with biocontrollers, and determination of residual contents of pesticides in bean seeds. The microbial populations corresponded to those previously registered for the lower tropics, but with quantitative differences in the genera. Phytophthora, Colletotrichum and Fusarium were registered in the humid Caribbean, while Colletotrichum and Curvularia affected crops in the dry Caribbean. The Beauveria bioinput was not compatible with the evaluated agrochemicals, while Trichoderma was compatible with chlorpyrifos, thiabendazole and oxycarboxin. Metarhizium was compatible with glyphosate and oxycarboxin at 10% of the recommended dose. Lindane residues were found in the beans harvested at three of the studied locations. The combined use of agrochemicals and bioinputs on bean crops is feasible as long as the time of application of the latter is made according to the half-life of the chemical and the organic matter content of the soil is increased.

Este trabajo presenta tres Buenas Prácticas que pueden brindar soluciones a la situación alarmante de inseguridad alimentaria y desnutrición que existe en la región Caribe colombiana, a pesar de tener alta potencialidad de producción de alimentos. Para identificar las Buenas Prácticas se indagaron a cerca de 400 profesionales de entidades públicas, privadas y ONG. Esa encuesta reveló tres ejemplos destacados de Buenas Prácticas que, con métodos distintos, generaron cambios positivos en la Seguridad Alimentaria y Nutricional de los habitantes de Sucre y Cesar. Adicionalmente, se sugirió que las tres Buenas Prácticas pueden ser replicadas y con poca dificultad incorporadas en los Planes de Desarrollo Departamentales. Si las iniciativas identificadas cuentan con el apoyo de los tomadores de decisiones, tienen potencial para fortalecer a los pequeños productores, reducir la inseguridad alimentaria y mejorar el estado nutricional de la población

This study identifies and evaluates examples of Best Practice that could offer new ways of addressing the continuing presence of food insecurity and malnutrition in the Caribbean region of Colombia, despite this region's food-producing potential. To identify the Best Practice, close to 400 professionals from public and private entities and NGOs were surveyed, revealing three outstanding examples of Best Practice which, in different ways, have had a positive impact on the food and nutritional security in the Departments of Sucre and Cesar. Additionally, it was shown that the three examples of Best Practice can be replicated and easily incorporated into Departmental Development Plans. If the initiatives identified by the study can count on the support of the decision makers, they have the potential to empower small producers, reduce the prevalence of food insecurity, and improve the nutritional status of the population.

Nutritional deficiencies are common among children in Colombia, and innovative strategies and supplements are needed in order to effectively address this problem. For example, in Colombia, when measured as ferritin, iron deposits are deficient in 58.2% of children between two and eight years of age. If a formulation is made with highly nutritional ingredients, cookies will have the potential to be used as supplements in children's diets because of their simple manufacturing process, long shelf life, and high acceptability. This study aimed to develop biofortified cookies, based on a bean-cassava-wheat flour mix, for children. The methodology grouped several studies in order to define the best treatment for the production of bean flour and the flour mix to produce cookies, prioritizing the nutritional content and the microbiological and sensorial quality. A production procedure for bean-based flour, suitable for the production of cookies with adequate nutritional, sensorial and microbiological characteristics was obtained. Additionally, the rheological characteristics of the proposed flour mixes permitted other possible uses for the bread-making industry, substituting cereal flours with flours with higher micronutrient contents. However, further studies are needed to determine the nutritional effects of the regular ingestion of biofortified cookies on children.

RESUMEN Estropajo (Luffa cylindrica L.) es una enredadera relacionada con el pepino y el melon, con muchos usos diferentes como filtros biologicos, material de empaque, artesania y la industria cosmetica. Como el estropajo requiere un clima caliente para su optimo crecimiento, es un cultivo apropiado para la costa caribena de Colombia. Uno de los retos del cultivo de estropajo es su baja tasa de germinacion y es recomendado hacer un pretratamiento de las semillas para mejorar la germinacion y establecimiento de las plantulas. Este estudio compara la germinacion y primer crecimiento de 75 semillas puestas a un pretratamiento hidrico con 75 semillas sin pretratamiento. Las semillas sin pretratamiento tuvieron una germinacion significativamente mayor a las semillas sometidas al pretratamiento desde el segundo dia del estudio, con una tasa de germinacion final de un 80% en comparacion con un 55% para las semillas pretratadas. De igual manera, las semillas sin pretratamiento tuvieron un mayor crecimiento que las semillas pretratadas aunque estadisticamente significativas solamente en tres de las nueve fechas de medida. Se concluyo que no es necesario, ni recomendable, hacer un pretratamiento hidrico de las semillas de estropajo antes de sembrarlas. Palabras claves: Estropajo, Luffa cylindrica, pretratamiento hidrico, preacondicionamiento hidrico, germinacion, crecimiento ABSTRACT Luffa (Luffa cylindrica L.) is a vine related to cucumber and melon which has many different uses such as in biological filters, as packing material, as material in handicrafts, and in the cosmetic industry. Since luffa requires a hot climate for optimal growth it is a suitable crop for the Caribbean coast of Colombia. However, one of the challenges of cultivating luffa is its low germination rate and therefore it is recommended to do a pretreatment of the seeds in order to improve the germination and initial growth of the seedlings. This study compares the germination and early growth of 75 seeds that have been pretreated in water with 75 seeds without pretreatment. The seeds without pretreatment had a significantly higher germination rate from the second day of the study compared to the pretreated seeds. The final germination rate for seeds without pretreatment was 80% while that of the pretreated seeds was 55%. The growth of the seeds without pretreatment was also higher than that of the pretreated seeds although the difference was only statistically significant at three out of the nine measuring dates. It was concluded that it is neither necessary nor recommended to expose luffa seeds to presoaking treatment before seeding. Key words: Luffa, Luffa cylindrica, presoaking treatment, hydropriming, germination, growth

Recommendations regarding P and K fertilization and critical soil and tissue concentrations for alfalfa (Medicago sativa L.) are inconsistent. Our objective was to use cluster analysis and binary logistic regression to determine if soil and herbage P and K concentrations can be used as diagnostics of P‐ and K‐limited alfalfa yields across soils with variable P and K soil test values. Samples were obtained from 28 consecutive harvests (four per year) of plots fertilized with four rates of P and five rates of K. Moderate to high rates of both nutrients were required to maintain high yields. Cluster analysis using May 2004 data for mass shoot−1 and shoots m−2 identified six clusters that also differed in yields. Averaged over the seven May harvests the two lowest yielding clusters had low herbage K (10.3–15.9 g kg−1), while intermediate yields were associated with low herbage P (1.6 g kg−1). Herbage P and K of the highest yielding cluster were 2.5 and 21.5 g kg−1, respectively. Plant populations in 2004 were the greatest with intermediate yields (61 m−2) and lowest for the poorest yielding plots (6 m−2). High taproot N reserves were associated with high yields. Prediction of acceptable (high‐yielding clusters) vs. unacceptable (low yielding clusters) performance was best achieved using the combination of herbage K and P concentrations and their ratio as independent variables. Results illustrate a varying, interdependent nature for alfalfa critical P and K tissue concentrations and suggest the need to account for both nutrients simultaneously.

Phosphorus (P) and potassium (K) increase alfalfa (Medicago sativa L.) yield, but little information is available on how forage nutritive value is affected by P and K fertilization. The objective of this study was to investigate the effect of long-term P and K fertilization on alfalfa yield-forage nutritive value relationships. A factorial experiment with four P and five K treatments was replicated four times. Beginning in 1998 and continuing through 2004, herbage samples were collected in May, June, July, and September. Samples were analyzed for crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), in vitro true dry matter disappearance (IVTDMD), and acid detergent lignin (ADL) using near-infrared reflectance spectroscopy. Soils were also analyzed for P and K concentrations. Concentrations of NDF, ADF, and ADL were reduced by low P and K fertility. Addition of P fertilizer increased CP concentrations, while addition of K fertilizer reduced CP concentrations. Concentrations of NDF, ADF, and ADL and dry matter yield decreased with stand age and harvest within year. The low forage dry matter yield of unfertilized alfalfa was associated with higher IVTDMD. Yield of digestible nutrients per hectare (yield x IVTDMD) was highly correlated with yield but not IVTDMD concentration. Fertilizing for high yield, despite the slight reduction in forage nutritive value, remains the most viable strategy for maximizing digestible nutrient production per hectare in alfalfa.

Fertilization with phosphorus (P) and potassium (K) is essential to maintain alfalfa productivity. Our objective was to examine how P and K fertilizer influenced alfalfa yield and yield components, plant persistence, and root physiology. Replicate plots of P (0, 50, 100, 150 lbs P2O5/A) and K (0, 100, 200, 300, 400 lbs K2O/A) treatments were arranged in a factorial design. Forage harvests occurred four times annually between 1998 and 2005 and yield, mass per shoot, and shoots per area were determined. Roots were dug in May and December of each year to estimate plant populations and determine whether plants were dying during (May to December) or during winter (December to May). Roots were analyzed for starch, sugar, amino acid, and protein concentrations. Total annual yield increased with application of P and K, but K application did not increase first harvest yield. Yield increases were due to greater mass per shoot, whereas stems/area were not related to forage yield. Plants died during summer and not during winter. Although P fertilizer increased forage yield significantly, it decreased plant populations by producing fewer but larger individual alfalfa plants. Fertilization with P alone resulted in faster stand thinning than observed in plots provided both P and K, and those left unfertilized. This rapid stand loss was associated with low concentrations of root reserves including starch, amino acids, and protein in taproots. Balanced P and K nutrition is essential to maintain stands and have high forage yield.