Latest News

July 21, 2014

Genome-wide analysis reveals divergent patterns of gene expression during zygotic and somatic embryo maturation of Theobroma cacao L., the chocolate tree: Siela N Maximova, Sergio Florez, Xiangling Shen, Nicolas Niemenak, Yufan Zhang, Wayne Curtis and Mark J Guiltinan BMC Plant Biology 2014, 14:185 doi:10.1186/1471-2229-14-185

July 9, 2014

Zhang Y, Smith P, Maximova SN, Guiltinan MJ: Application of glycerol as a foliar spray activates the defence response and enhances disease resistance of Theobroma cacao. Molecular Plant Pathology doi:10.1111/mpp.12158 (2014).

July 1, 2014

Huck scientists find Theobroma cacao trees' natural disease defense is bolstered by glycerol foliar treatment

April 27, 2014

Zhang, Y., Clemens, A., Maximova, S. N. & Guiltinan, M. J. The Theobroma cacao B3 domain transcription factor TcLEC2 plays a duel role in control of embryo development and maturation. BMC Plant Biol 14, 106, doi:10.1186/1471-2229-14-106 (2014).

Left to Right: Abu Dadzie, Lena Shaeaffer, Desire Pokou and Grace Garbini, discussing the isolation of three genes from cacao potentially involved in disease resistance.
September 13, 2013

We are hosting the visits of two outstanding cacao scientists from West Africa. Desire Pokou (Ivory Coast) and Abu Dadzie (Ghana) are both cacao breeders and involved in using the new tools of molecular markers to help accelerate breeding programs.

U.S. Department of Agriculture Under Secretary for Research Education Cathie Woteki, left, and U.S. Agriculture Secretary Tom Vilsak, third from left, toured a laboratory in Penn State's Life Sciences Building on May 16, hosted by Assistant Professor of B
June 11, 2012

U.S. Agriculture Secretary Tom Vilsack visited Penn State's University Park campus on May 16, accompanied by Cathie Woteki, the U.S. Department of Agriculture under secretary of research education. The visit included tours of research laboratories, a meeting with Penn State faculty and representatives from 4-H and FFA. The one-day visit commemorates the 150th anniversary of both the U.S. Department of Agriculture and the Land Grant University System.

June 30, 2011

Award from World Cocoa Foundation was received by Mark Guiltinan at the Annual WCF meeting in San Francisco, CA on behalf of all members of the International Cocoa Genome Sequencing Consortium.

June 23, 2011

Title: Deficiency of maize starch-branching enzyme i results in altered starch fine structure, decreased digestibility and reduced coleoptile growth during germination.

April 20, 2011

Title: Starch Branching Enzyme IIa is required for proper diurnal cycling of starch in leaves of Zea mays.

December 26, 2010

Published in Nature Genetics 43:101-108 (2011). On behalf of the International Cocoa Genome Sequencing Consortium, a collaborative partnership representing20 institutions from 6 countries around the globe, we are pleased to announce the release of our publication. The sequence and its analysis have revealed many amazing discoveries.

September 16, 2010

The sequencing and analysis of the genome for the Criollo variety of the cacao tree, generally considered to produce the world's finest chocolate, was completed by an international team led by Claire Lanaud of CIRAD, France, with Mark Guiltinan of Penn State, and included scientists from 18 other institutions.

August 11, 2010

This NSF award by the Biotechnology, Biochemical and Biomass Engineering program supports work to develop low-cost bioreactor systems that will enhance the ability to utilize tissue culture to improve agricultural plant productivity. In addition to the typical paradigm of optimizing the chemical and environmental conditions within the bioreactor, this research seeks to demonstrate the ability to control plant development using transcriptional factors that control the expression of multiple genes. These transcriptional factors will be delivered to the plant tissues using Agrobacterium, a bacteria that has been developed to transiently deliver DNA to cultured plant tissues (developed with previous NSF support; BCS-0003926). The genes associated with plant embryo formation will be identified by examining patterns of gene expression during somatic embryogenesis. The concept of inducing embryo formation will be implemented using Cacao, the source of chocolate, due to its commercial (and social) value. In addition to providing an instructional case study that demonstrates the use of interdisciplinary principles of bioreactor design and molecular biology, the effort will produce thousands of fungal resistant plants that will be distributed to smallholder farmers in South America. In addition, the low-cost bioreactor technology has potential applications to a broad range of food and biomass crops.

May 12, 2010

Small-holder agriculture in developing countries is exceptionally susceptible to fungal and oomycete disease due to lack of local breeding programs, tropical climate, abundant insect vectors, cost of and poor access to fungicides, and lack of farmer education. Small-holder farmers in Africa and South America are responsible for more than 95% of cacao production, providing economic benefits to millions of cacao farmers and their dependents, as well as important ecological benefits such as rain-forest preservation. Fungal and oomycete diseases have devastated cacao production in South America and West Africa, dislocating populations of farmers and resulting in destruction of the rain-forest sheltering the cacao trees in favor of large-scale open farmland. This project will test two novel approaches to protecting developing country crops against a broad-spectrum of oomycete and fungal pathogens, using cacao as the initial target. The first involves targeting anti-microbial proteins to pathogen feeding structures called haustoria, using RPW8, an Arabidopsis protein that has a natural affinity for these feeding sites. The second approach involves blocking the entry of virulence proteins (effector proteins) that pathogens secrete into host cells to suppress the plant host's immune system. The most effective strategies will be identified first using fast growing Arabidopsis and tomato plants before being tested in cacao.

May 1, 2010

As an intern at Pioneer Seeds, Gouker helped develop techniques to make genetic super corn. “Half of my time was spent doing tissue culture work in the lab, growing plants in vitro, and the other half was spent outside in the field, performing thousands of pollinations,” he said. Returning to Penn State, Gouker resumed his research at Mark Guiltinan’s lab, where he’s worked since a freshman, and took on a new project with Majid Foolad. Both projects explore the jatropha plant as a source for renewable energy. Fred is now a graduate student in the Plant Breeding Program at Cornell.

April 14, 2010

TITLE: Isolation of Genes Involved in Oil Biosynthesis in the Biofuel Feedstock Plant Jatropha curcas. Jennifer cloned and sequenced several key genes in the oil biosynthesis pathway of Jatropha. She presented a poster and an honors thesis on her work, graduating with honors in June of 2010. She won an award for her poster and the Penn State Undergraduate Research Exhibition.

June 1, 2001

Join a team of Penn State researchers and our own intrepid reporter in Trinidad as they kick off “Plants Without ,” a project aimed at sharing some of the latest technology for growing one of the world’s favorite crops — cocoa. During ten days in-country, associate professor of plant molecular biology Mark Guiltinan and his team built a greenhouse for raising cocoa seedlings, complete with irrigation system. They also gave a workshop in cocoa-propagation techniques for local farmers, met with scientists from the country’s Ministry of Agriculture, and visited one of the world’s largest cocoa seed-banks. Associate editor Dave Pacchioli, accompanied the team, and sent back real-time dispatches on their progress.

May 1, 2001

Article by David Pacchiolo. From "Plants Without Borders" in Trinidad

January 1, 2001

Melis Cakirer, MS student studied how the colors of cacao seeds can be used to understand the basic profiles of flavonoids in seeds. Read about her research in this short article.