Potatoes: New pests, new varieties and new biocontrols

The potato, originally from the Andes Mountains, was introduced to Europe in the 16th century. Its introduction significantly reduced reliance on cereal crops and facilitated its spread globally. Over the past five centuries, the potato has become a crucial food crop for farmers and consumers worldwide. During periods of conflict, such as World War II, potatoes were essential for food security due to their high yield potential and minimal processing requirements.

Today, there is a global call to reimagine food production, processing, and consumption. Innovations in cropping systems management and the development of new potato varieties are critical steps in integrating potatoes into more diverse and resilient farming systems. Potatoes can contribute significantly to environmentally sustainable and profitable production systems due to their wide availability, high yield potential, and culinary versatility.

Here are some new developments around potatoes, including a newly reported pest, an innovation in biorational pest control, and new varieties being developed:

Three new potato varieties have been put forward following a trial in Peru.

Recent developments in potato research include the identification of a new pest, advancements in biorational pest control, and the development of new potato varieties. For instance, three new potato varieties have been proposed following trials in Peru. In Peru, the demand for potatoes, particularly for French fries in restaurants, is increasing daily, typically met by imported pre-fried potatoes.

During the 2019-2020 and 2020-2021 growing seasons, trials were conducted on 10 potato clones from the International Potato Centre breeding program and two Peruvian varieties used as controls. These trials, conducted in farmers’ fields across northern, central, and southern Peru, utilized a randomised complete block design with three replications of 150 plants each.

The trials evaluated late blight severity and yield under field conditions, and laboratory tests determined dry matter and reducing sugar content. Three clones were selected for their high resistance to late blight, yields exceeding 30 t/ha, and excellent quality for French fries. These selected clones have been registered as new varieties in Peru’s official cultivar register.

The introduction of these new varieties can improve the standard of living for small to medium-scale potato farmers, support the health of the producers and consumers, and benefit the environment. Additionally, these varieties can serve as parent lines in breeding programs worldwide.

New potato pest- Schrankia costaestrigalis (pinion-streaked snout)

A new pest, Schrankia costaestrigalis (commonly known as the pinion-streaked snout), has been reported to cause significant economic losses to potato farmers in China during the winter and early spring planting periods. This pest has also been recorded in Europe, Central and North Asia, North Africa, and Australia. The larvae of S. costaestrigalis feed on various herbaceous and woody plants, including thyme flowers, and damage potato tubers by feeding on both the tubers and foliage, either in the field or during storage. The resulting damage, characterized by holes exuding honeydew, significantly reduces the market value of the potatoes and leads to losses at harvest.

Historically, S. costaestrigalis has rarely been identified as a crop pest, with notable exceptions being Vicia faba in Japan and potatoes in China. The pest was first detected in Yulin City, China, in 2015 and has since been recorded in seven other counties and two cities (Yulin and Huizhou). Currently, its occurrence is geographically limited to parts of southern China. However, if it continues to spread, it could pose a significant threat to local potato planting and production.

In 2019, S. costaestrigalis was also found to damage sweet potatoes. Due to the lack of host plants in the fields after the potato harvest, the pest is forced to transfer to surrounding crops such as sweet potatoes. However, recent surveys have not found adults on surrounding plants in potato-planting areas, suggesting that S. costaestrigalis primarily causes damage to potatoes and sweet potatoes in China. The pest may spread through the long-distance transport of potato tubers carrying larvae.

Previous studies in China have focused on exploring the occurrence and damage frequency of S. costaestrigalis in fields, as well as developing agricultural and chemical control measures. While the exact distribution of this pest is currently unknown, determining its extent is crucial for creating an early warning and monitoring system.

Nearly complete genome sequences of the first two identified Colorado potato beetle viruses

The Colorado potato beetle is one of the most devastating pests affecting potato crops globally. Despite its significant impact, the viral pathogens that could potentially be used for its control have remained largely unexplored.

Through the use of high-throughput sequencing on samples from prepupal larvae of the Colorado potato beetle that succumbed to an unknown infection, researchers identified two novel RNA viruses and assembled their nearly complete genome sequences. These viruses, named Leptinotarsa iflavirus 1 and Leptinotarsa solinvi-like virus 1, are the first sequencing-confirmed insect viruses derived from the Colorado potato beetle. Genetic analysis revealed that these viruses belong to the Iflaviridae and Solinviviridae families, respectively. The researchers suggest that Leptinotarsa iflavirus 1 may be linked to a lethal disease in the Colorado potato beetle, potentially offering a novel biocontrol method for managing this notorious pest in the future.

Sources

https://link.springer.com/article/10.1007/s11540-024-09697-1

https://www.sciencedirect.com/science/article/pii/S2095311922001010

https://www.nature.com/articles/s41598-023-51093-1