Agricultural Biotechnology

Kariana Feliciano López, B.S.
Alexis Fontán Jiménez, B.S.
Alfredo Miranda Aponte, B.S.
Orlando Roig López, B.S.
Juan A. Negrón Berríos, Ph.D.
Interamerican University of Puerto Rico
Barranquitas Campus

Arracacia xanthorrhiza is an edible tuber in many South American countries, such as Brazil, Venezuela and Peru. In Puerto Rico Arracacia xanthorrhiza is produced by small groups of farmers in the center of the island for local distribution. Tuber cultivation in soil tends to be greatly affected by weather conditions, cultivation time, and pests such as viruses, bacteria, and fungi. Many of the problems could be avoided by developing cultures in vitro using micropropagation techniques in the laboratory. Through cultivation in laboratories, we can obtain seeds and explants that can be subsequently harvested on farms. In this project, the micropropagation of the plant Arracacia xanthorrhiza can be directed through meristematic, petiole, and tuber culture. Two different disinfection protocols were used to eliminate all pathogens. The middle Murashige & Skoog (MS) developed shoots and calluses with a combination of different growth factors. Benzyladenine and naphthalene acid with the MS medium, produced callus through the petioles. However, benzyladenine with MS medium developed shoots from the meristematic tissues and tubers. Finally, disease-free explants can help farmers market healthy tubers.

Rosalinda Aybar Batista, B.S.
Alba Marrero Rodríguez, B.S.
Arleen Jiménez Ortiz, B.S.
Juan A. Negrón Berríos, Ph.D.
Interamerican University of Puerto Rico
Barranquitas Campus

The Theobroma cacao is a plant native to South America, belonging to the Malvaceae family. It is considered a strictly tropical crop, whose genus is composed of 21 species found mostly between latitudes 18 degrees north and 15 degrees south in humid climates. Although cocoa is located in humid tropical climates, this product is consumed worldwide. Currently a disadvantage of the production is the great global demand to be used in the confession of chocolate. For this reason, the market is not highly developed but has good potential economically. Traditionally, cocoa is propagated sexually by seed and asexually by grafting. Propagation by seed is extremely easy and cheap, but the generation of heterozygotes makes it difficult to maintain a high-quality crop by causing genetic variability in the progeny. Micropropagation presents an alternative for in vitro cultivation for cocoa, in this way it will be possible to obtain thousands of high quality seeds. In addition to this, explants generated by micropropagation represent an excellent model for research. This project helps to find a calibration and disinfection protocol for cocoa micropropagation of the somatic tissues of the leaf, stem, petiole and bud of the plant tip. Callus development was observed as a result of the cultures. They can later be used as guide tissue for the ability to fully develop a desired tissue depending on the conditions to which they are exposed.

Arleen Jiménez Ortiz, B.S.
Juan A. Negrón Berríos, Ph.D.
Interamerican University of Puerto Rico
Barranquitas Campus

The grape is a plant that has been cultivated since ancient times. These belong to the genus Vitis, to the family Vitaceae; native to the Mediterranean, Central Europe, and southwestern Asia. Due to our tropical climate, grapes in the Caribbean can produce two to three harvests a year, so this fruit has strong marketing potential as table fruit, vinaigrettes, wines, juices, etc. A limitation to achieve this goal is the need to identify grape species with good adaptation to tropical climate, standardization of propagation techniques and the lack of research applied to grapes in the Caribbean. There are a limited number of grape varieties that have shown the ability to adapt to the Caribbean. Vegetative propagation has been widely used in grape varieties; Therefore, micropropagation offers faster and more efficient methods for the production of pathogen-free populations and for amplifying genetic variation in selected crops. We have applied micropropagation to two grape varieties that have shown the ability to adapt to tropical climates. Our main goal is to improve productivity and add value to these grape varieties through micropropagation. A specific culture medium for shoot development was prepared; in which the explants were cultivated in this medium with growth regulators to generate roots and shoots. Different concentrations of auxins and cytokines were used to promote cell division. On the other hand, callus formation was induced by concentrations of cytokines and auxins.

Sullymar Morales Marrero, MEd.
Tatiana Ortiz Torres, MEd.
Carlos Vázquez Delgado, M.T.
Juan A. Negrón Berríos, Ph.D.
Interamerican University of Puerto Rico
Barranquitas Campus

The plant Calathea allouia (better known as; Lerén), is an oil species that has had well-marked cultural aspects in the history of Puerto Rico, due to the fact that the Taínos harvested it for their own consumption during the Precolumbian era. The tuberous roots of the lerén are consumed cooked and their texture remains crisp even after a long time of cooking, a characteristic that makes it very appetizing.

In addition to its consumption in isolation, the lerén can be a component of salads and other dishes made from fish. Currently, the tubers of the plant have been replaced by other foods of economic interest on a large scale. So, the abandonment of the plant during the last centuries has meant that it can be threatened and can be considered in danger of extinction.

José Otero Rosado, B.S.
Juan A. Negrón Berríos, Ph.D.
Interamerican University of Puerto Rico
Barranquitas Campus

Extensive agriculture, storage and the environmental by-products of climate change have resulted in bringing Heliconias species to the brink of extinction. Therefore, the need to develop research protocols that help restore the stable existence of Heliconias species is necessary, in order to avoid their extinction. A work protocol was developed in the laboratory using various tissue propagation methods including (a) embryo culture extracted from mature seeds, which were inoculated into different components of basal medium ranging from 1/2 liters of medium Linsmaier and Skoog (LS), 1/2 liter of Murashige and Skoog (MS) medium and 1/3 liter of LS basal medium with 17.6 micromolar BAP; (b) leaf culture where leaf explants were inoculated into LS and MS basal medium both varying IAA concentrations (2.85 micromolar, 5.71 micromolar, 17.13 micromolar and 22.84 micromolar) and (c) shoot culture where shoot tips were inoculated with 1/2 liters of basal LS medium and 1/2 liter of basal medium with 17.6 micrograms of BAP. The best result of tissue propagation was achieved with the culture of embryos in 1/2 liter of LS basal medium in which they developed into seedlings at 10 days. The results obtained, in the long term, is to be able to promote the massive propagation of the Heliconia species that are currently in danger of extinction and eventually restore the flora and the ecological system.