Summit Agro USA has extended its field trials for its hybrid fungicide REGEV to a variety of crops – potato, grape, apple, blueberry, tomato and watermelon.

Summit Agro USA is the exclusive distributor of STK Botanical Biopesticides and Innovative ‘Hybrids’ in the USA.

REGEV is STK’s first hybrid fungicide product, which comes in a ratio of 2:1 of tea tree oil (TTO) and difenoconazole. The company also has another formulation of Regev, known as Regev HBX, which comes in a 1:1 ratio, and is registered for use on pecans, soybeans, and rice.

Dr. Eric Tedford, Field Research Manager of Summit Agro USA has been sharing new field results on a wide variety of fruits and vegetables using Regev, which is used in 14 countries, including the USA.
Regarding potato, Tedford told New AG International that the product had performed well and showed ‘good control of early blight’.

The company commissioned trials on grape against Black Rot and Powdery Mildew. The results were collected during trials in 2022 in New York state, performed by Assistant Professor of Grape Pathology at Cornell University Katie Gold. Regev was found to be effective against black rot in both clusters and leaves.

The trials for powdery mildew were performed at three sites in California in 2022, at various application rates of Regev, one being 8.5 oz/acre. Some of the trials were also combinations with specific adjuvants, such as Regev plus Dyne-Amic at 0.125%, or Kinetic 2.58-3 oz. Regev was also effective against powdery mildew in watermelons, early blight on tomatoes, and efficacy against shoot strikes on blueberry.

Tedford explained in an earlier interview that TTO contains eight different terpene hydrocarbons and so is more akin to conventional chemistry. “TTO has eight active ingredients with multiple mechanisms for its activity.” (See more here on the launch of STK’s second hybrid product, which contains TTO.)

Tedford told New AG International that Summit Agro USA was carrying out more trials with Regev in 2023. “We put out 66 trials with Regev or Regev HBX in 2023.”

The trials for almond covered the following diseases: Alternaria, brown rot, gray mold, bacterial spot, scab, and hull rot.

Cherry, citrus, peach, onion, peanut, pecan, strawberry, rice and soybean were among the tested crops.
“We had excellent results in most of these trials, with efficacy equal to many of the standard fungicides for these crops,” said Tedford.

Classification benefits

“With many of the fungicides on the market today being either 3s, 7s, or 11s, or combinations of two or three of these, Regev is an excellent new product for resistance management purposes. TTO has been designated by the Fungicide Resistance Action Committee (FRAC) as a BM01 fungicide. This classification is different from the 3s, 7s, and 11s, and it has low resistance risk.”

Regev can be used in programs to help reduce the risk of fungicide resistance development, explained Tedford. “The TTO does not impart a residue, so the only residue growers need to concern themselves with for MRL considerations are for the triazole component of Regev.”