Meet the Team

With more than 200 years of industry experience, our team includes fruit breeders, technicians, research agronomists, global licensing staff, marketers, agricultural technology- and IP specialists. As the longest standing and one of the world’s largest fruit breeding and research programs, we pride ourselves on our long history of bold, successful variety development. Our team is committed to the success of our licensees. We providing them with extensive technical support and carefully develop and commercialize our new varieties to ensure they will be appreciated by growers, customers, and consumers.


David Marguleas, President

David is based in Palm Desert, California and oversees Sun World’s Intellectual Property, licensing and variety development activities as well as the company’s broader agriculture technology pursuits and international investments. A third-generation member of the produce industry, David earned his bachelor’s degree in Communications from Cornell University’s College of Agriculture and Life Sciences. He began his Sun World career in1986. David has been integral to the development of the Sun World brand in the United States and internationally, and has driven the global development of its stonefruit and grape varietal brand strategy.

Keith Mitchell, Executive Vice President and Chief Financial Officer

Keith is responsible for all finance and administrative functions including accounting, human resources, and IT.  He has worked in the produce industry for more than 25 years, and joined Sun World in 2014.  Keith has a BS in accounting, an MBA, and is a Certified Public Accountant.

Jeff Jackson, Executive Vice President of Business Development

Jeff is an accomplished produce industry executive with deep farming, supply chain, business development, marketing and general management experience. After obtaining advanced business and law degrees from U.C. Berkeley, he held senior management positions at various iconic produce companies. He joined our team in 2019 in a new role as Executive Vice President of Business Development and is responsible for spearheading new growth initiatives. Contact Jeff


Mistie Miller, Intellectual Property Manager

Mistie is based in Bakersfield, California and is charged with the task of managing the intellectual property portfolio for the global licensing business in conjunction with Sun World’s IP lawyers. She has been with the company since 2011, initially involved with licensing agreements and insurance. Mistie is a Paralegal and holds a B.A. in Psychology. Contact Mistie

Dané Joubert, Marketing Manager

Dané is responsible for promoting existing and emerging Sun World proprietary fruit varieties, brands, agricultural technologies and licensing services to licensees, importers, retailers and media representatives. An important role for Dané is maintaining and enhancing communications with Sun World’s licensees, which includes managing the website, photography, newsletter and social media platforms. Originally from a South African table grape farming family in the Hex River Valley, she is a graduate of California Polytechnic University at San Luis Obispo with a degree in business marketing. Dané brings great energy and creativity – as well as keen fruit industry insights — to Sun World. Contact Dané

Josh Mellor, Senior Analyst

Josh joined the Sun World licensing team in October 2017. This is a new role in the business which makes him responsible for all projects globally and includes – business analysis framework, supply and demand analysis and forecasting and financial modeling. He brings extensive experience across the entire horticultural supply chain from seed to retail, including managing intellectual property, licensing, retail brands, category and farm projects, new product development, crop forecasting and supply. Having grown up on a cotton, wheat and cattle station in western New South Wales, Australia Josh has a strong connection with agriculture – he’s passionate about its people and the opportunities for growth. Contact Josh


Garth Swinburn, Vice President of Licensing

Garth joined Sun World in 2011 and is responsible for all global licensing staff and activities, including offices in South Africa, Chile, Europe, Australia and California. He has spent the last 35 years in fruit production, horticultural developments and the marketing of fresh produce. Much of his professional career has been in providing independent consultancy services to agribusinesses in Australia in crops such as grapes, citrus, stone fruit and almonds. Garth holds a B.Hort from Lincoln University, NZ, a post-graduate Dip.Ag.Econ from the University of New England and an M.Agribus. from the University of Queensland. Contact Garth

Adam Knoll, Licensing Manager, Australia

Adam joined Sun World in 2016 and is responsible for our licensing business in Australia. Distinguished by his passion as a career horticulturist, Adam has extensive operational experience in large scale production horticulture and the Australian nursery industry. Over his career, Adam has built a reputation for business development and developing horticultural intellectual property agreements. Adam holds a Dip. AppSci (hort) from the University of Melbourne. Contact Adam

Maurizio Ventura, Licensing Manager, Europe

Maurizio has been responsible for the Sun World licensing business in Italy, Spain, Portugal and France since 2006. His background includes genetic improvement of apple varieties, research in germplasm and fruit ripening and the use of NIR technology. He has also been involved in phytosanitary certification and quality assurance in the plant nursery industry. Maurizio holds a PhD from the University of Bologna. Contact Maurizio

Dirk Burger, Licensing Manager, South Africa

Dirk joined the Sun Word Licensing team in 2010 and comes from a research background in post-harvest storage of grapes and technologies that improve the quality of stored fruit. His past work has also provided him with valuable insights into the use of plant growth regulators on table grapes. Dirk holds a BSc in Horticulture and an MSc (Hons) in Viticulture from the University of Stellenbosch, South Africa. He is currently a member of the Deciduous Fruit Producer’s Trust. Contact Dirk

Hovav Weksler, Applied Research Director & Licensing Manager, Israel

Hovav has an extensive background in production horticulture and is based in Israel.  He has been part of the team ever since the licensing business first began in 2000. Tracing back to the 2000’s until today he provides consulting services to growers worldwide. In 2020 he was appointed Applied Research Director. He also is responsible for the company’s Israeli licensing business. Hovav holds a B.Sc. and an M.Sc. (candidate) in agronomy. Contact Hovav

Petri van der Merwe, Licensing Manager, North America

Petri joined the Sun World team in 2018. He is responsible for the Sun World licensing business in California and Mexico. Petri brings considerable skills and experience to the Sun World licensing programs with over 20 years in the global fast-moving consumer goods industry and a focus on fresh produce. His background includes new variety and product development, commercial operations, procurement, supply chains and key account management with a leading South African based multi-national business. More recently, Petri had his own consultancy business in South Africa providing a range of services, including market development support to fresh produce suppliers. Contact Petri 

Pablo Ramirez, Licensing Manager, Peru

Pablo is the newest member of our team and joined Sun World in 2019. Pablo is responsible for the Sun World licensing business in Peru, to help direct, manage and assist Peruvian licensees. He holds an Agricultural Engineering degree from the National Agrarian University La Molina in Lima, Peru. He has been involved in the Ag business for the past 12 years, first working as a Commercial Manager in the narrow coast of Peru where modern agriculture was established, and where he started his own business offering commercial consulting to growers and exporters. In that role, Pablo has also been an advisor to Sun World for 3 years. Contact Pablo

Daniel Desmartis, Licensing Manager, Chile

Daniel joined the Sun World team in Dec 2019. Daniel is responsible for the Sun World licensing business in Chile. He holds an Agronomy degree and is currently studying for a Masters in Innovation. He spent 6 years working with Univiveros (Sun World licensed nursery) and 7 years working for Gesex (Sun World licensed grower and marketer) as Head of Research & Development (R&D). He was responsible for variety evaluation, plant material imports, liaison with growers, nurseries and other service providers and the management of their experimental farms. Contact Daniel

Andrea Pavesi, Licensing Manager, Brazil

Andrea holds a Bachelor’s degree in Agronomy at the Universidade Estadual Norte do Paraná in Bandeirantes,  Parana State. He has been involved in the Ag business in Brazil for the past 30 years, first working for Unilever as a technical assistant and then the Manager of their research and development program. In 1997, Andrea started his own business in Petrolina, growing mangos, grapes, and other annual crops. Prior to Andrea’s appointment as the Peruvian Licensing Manager, he worked closely with Sun World as a consultant for 12 years. Contact Andrea

Variety Development

Terry Bacon, Vice President of Variety Development

Terry has been with the company since 2000 and is based at the Variety Development Center in Bakersfield, California. He directs fruit breeding and commercial testing operations as well as coordinating field and post-harvest research. He also works closely with licensing technical staff members to help develop ‘best practices’ tech support for Sun World’s grape and stone fruit varieties. Terry holds a Master of Science in Fruit Breeding from Texas A&M University and is a contributing member of the Table Grape Breeders Association and the Stone Fruit Breeders Association. Contact Terry

Terrence Frett, Assistant Breeder

Terrence joined Sun World in 2016 to support the expanding breeding programs with his skills and new technologies. He manages the molecular breeding laboratory at the Variety Development Center and works in field and post-harvest research with Terry. He holds a Master of Science from Clemson University, South Carolina, where he studied peach breeding, and he was awarded his PhD at the University of Arkansas, where he developed his knowledge on marker-assisted parent and seedling selection. Terrence is a member of the American Society of Horticultural Sciences, RosBREED and VitisGEN.  Contact Terrence

Sharon Rosenthal, Laboratory Manager

After working in the plant-breeding department of the USDA, Sharon joined the Sun World team in 1987. She manages the plant tissue culture lab and oversees the greenhouse management and global material distribution. Sharon is a member of several industry organizations including the International Plant Propagators’ Society, the American Society for Horticultural Science, and the Society for In Vitro Biology.Contact Sharon

Gary Lott, Director of Operations, Table Grape Breeding Program

Gary manages crossing and farming operations for the table grape breeding program. His duties include managing the table grape seedling, Commercial Test blocks, and coordinating labor and propagation. Gary first fell in love with agriculture while volunteering on a reforestation project in Haiti in the early 80s. Gary earned his MS degree in Agriculture from UC Davis and joined the Sun World team in 1989. In his spare time, he enjoys sports, camping, hiking, music, and time with his family. Contact Gary

Larry Okumoto, Research Associate, Stone Fruit Breeding Program

Larry manages crossing and farming operations for the stone fruit breeding programs. His duties include orchard and hybrid seedling block management for the peach, nectarine, plum, apricot, cherry, and rootstock breeding programs. Larry grew up on a family plum and raisin farm in central California and has rich experience in farming, greenhouse, and propagation operations. Larry earned his MS degree from UC Riverside and joined the Sun World team in 1990. Contact Larry

Margarito Quintana, Research Associate, Table Grape Commercial Testing

Margarito manages commercial testing at the table grape breeding program. His duties include execution and management of over 300 individual commercial testing and rootstock trial experiments performed each year at the Center. He also manages post-harvest and storage trials data and data entry for over 100 varieties each year. Contact Margarito

Esther Niu, Research Associate, Molecular Breeding

Early in 2017, Dr. Esther Niu joined the Variety Development team as research associate of the Innovation Molecular Lab. Today, under the leadership of Dr. Terrence Frett, Esther is helping to advance Sun World’s breeding efforts using molecular markers, a non-GMO tool for improving the efficiency of breeding for traits such as disease resistance. Esther is originally from Beijing, China, where she studied plant pathology at China Agricultural University. Her interest in plant-microbe interaction helped her to obtain an assistantship in a plant virology lab at Oklahoma State University. She then went on to earn her doctorate in botany and plant pathology at Purdue University in Indiana. Contact Esther

Grower Support Services

Hovav Weksler, Applied Research Director & Licensing Manager, Israel

Hovav has an extensive background in production horticulture and is based in Israel.  He has been part of the team ever since the licensing business first began in 2000. Tracing back to the 2000’s until today he provides consulting services to growers worldwide. In 2020 he was appointed Applied Research Director. He also is responsible for the company’s Israeli licensing business. Hovav holds a B.Sc. and an M.Sc. (candidate) in agronomy. Contact Hovav

Michele Melillo, Director of Technical Assistance

Michele has been an independent viticulturist since 2004, based in Europe but with extensive experience in Australia, North Africa and South America. He joined the Sun World team as a consultant for Europe and Australia in 2014, and in 2019 was appointed Director of Technical Assistance. He is responsible for the Technical Assistance Team, which delivers support to SW licensee worldwide in agronomic management and cultural practices. Michele holds a B.Sc. in Agronomy at the University of Bari, Italy and an M. Sc. in Horticulture and Agronomy at UC Davis, California.  Contact Michele

Chris Hanssens, Applied Research Agronomist Chile

Chris, a fellow stonefruit intern at Sun World in 2014, joined the Sun World team in 2020 as the Research Agronomist for Chile. She holds an Agronomist degree and M. Sc. in Plant Physiology from Pontificia Catholic University in Chile. Her experience extends to table grapes and stonefruit. She worked for 5 years in Tuniche Fruits (a Sun World stonefruit licensed) as Head of Research & Development, and then 3 years at a breeding company in South America as Technical Manager, providing technical support to licensed table grape growers. Contact Chris

Norka Valdivia, Technical Assistance and Applied Research Agronomist Peru

Norka joined the Sun World team in 2020 as the technical and research agronomist for Peru. Norka holds a Bachelor’s degree in Agronomy and a Master’s in Agricultural Business Administration and Agricultural Production. To date, Norka has more than 18 years of experience working with table grapes. She spent 13 years working for Don Ricardo (a Sun World licensed grower and marketer) and more recently worked for Agrícola La Venta as Technical Agronomist and Agricultural Manager. Contact Norka

Robert Oosthuizen, Technical Assistance Agronomist South Africa

Robert joined the Sun World team in December 2015 as a technical assistant for South Africa. Before he joined the Sun World team, he was a farm manager in the Paarl region and farmed with wine grapes, olives, stone fruit, citrus, guavas and buchu. He holds a National Diploma in Agricultural Management from the Cape Peninsula University of Technology. Contact Robert