New Resource for Improving Pistachio Quality

California generates around $3 billion in economic value from the production of 99% of the country's pistachios. The absence of a high-quality DNA map, however, has contributed to the minor understudies of pistachios.

Researchers from the University of California, Davis have now produced the most complete genome sequence of the pistachio, enabling plant breeders to produce improved possibly more nutrient-dense variety. Additionally, they have described the development of pistachio nuts, which will assist farmers in managing their crops more sustainably.

The study was published in the journal New Phytologist.

Although pistachio DNA has previously been mapped, Co-Corresponding Author J. Grey Monroe, an Assistant Professor in the Department of Plant Sciences, said that this new genomic map is far more precise and comprehensive.

The improvement in accuracy of the new reference genome is like going from a hand-drawn map of a landscape to a satellite image from Google Earth.”

J. Grey Monroe, Study Co-Corresponding Author and Assistant Professor, Department of Plant Sciences, University of California, Davis

The genome of the Kerman cultivar, the most widely grown pistachio variety in California, was sequenced by Monroe and the study team.

Climate Change Challenges Pistachio Yields

Despite their resistance to salinity and drought, pistachio plants need cold winters to bear fruit. New pistachio types that can withstand higher temperatures are needed by growers when climate change results in warmer winters. Growers of pistachios have suffered large losses as a result of warm winters and the dissipation of fogs that chill California's Central Valley.

According to academics, California growers are naturally worried about how climate change could affect their crops because planting a pistachio tree can take up to 50 years.

A Nutty Development

A thorough physiological evaluation, including shell hardening and kernel growth, is provided by the study, which also identifies four critical phases of nut growth from bloom to harvest.

Knowing how the nut changes through development will help farmers make better decisions, like when to water their trees, leading to more sustainable pistachio production.”

Bárbara Blanco-Ulate, Study Co-Corresponding Author and Associate Professor, Department of Plant Sciences, University of California, Davis

A more precise evaluation of its growth might also help growers avoid problems like fungal infections and insect damage and offer them better harvesting techniques.

Blanco-Ulate stated that it was crucial to describe not just the pistachios' morphological alterations but also the chemical and genetic factors that contribute to such changes. Precedent-setting details about the behavior of several genes in nuts throughout the growth season are included in the genomic sequence.

Nutritious Nut

Although pistachios have traditionally been a nutrient-dense meal, scientists have now identified the genes and mechanisms that affect their nutritional content. This contains information on the accumulation of protein and unsaturated fatty acids, which is important for their nutritional value and shelf life.

“We are getting information about how all these nutritional characteristics are gained in pistachios and how we can improve that from a management perspective,” said Blanco-Ulate.

With this knowledge, researchers may be able to produce more nutrient-dense pistachios in the future.