New breakthrough achieved in prevention and control technology for a stubborn disease of peach trees

Starting in mid-May, "fresh peaches from Zhejiang" came onto the market one after another. Zhejiang's peach cultivation area is nearly 410,000 mu, making it an advantageous industry among the province's agricultural products with the potential to compete internationally. But Zhejiang's peach trees have long been plagued by a "stubborn disease." However, a reporter recently found in a peach orchard in Chun'an County, Zhejiang, that this disease, which had gone untreated for years, has been effectively cured here.

It is understood that this "stubborn disease" is called peach tree gummosis, which is divided into physiological gummosis and infectious gummosis. Its pathogenic factors are complex and its epidemic areas are widespread, being especially severe in southern peach-producing regions such as the Yangtze River basin in China. So-called gummosis often involves the blister spots on peach tree branches and trunks rupturing and exuding a colorless, transparent, soft gum. After oxidizing in the air and condensing and drying, it turns reddish-brown, the cortex and xylem turn brown and necrotic, and the area beneath the cortex becomes filled with sticky gum fluid.

Zhang Huiqin, a researcher at the Zhejiang Academy of Agricultural Sciences, and her team of 6 people in total began piloting and exploring a complete set of whole-process prevention and control technical protocols in 2013 in 3 peach orchards including Chun'an, Zhejiang, covering the causes, occurrence characteristics, symptoms and integrated prevention and control of peach tree gummosis. After several years, through comparison it was found that in the three pilot orchards, peach tree gummosis had basically disappeared.

How exactly is it done? The reporter learned that in early winter, the first step is to plow the soil in the tree basin or within the rows to kill pathogens and pests overwintering underground, while also scraping off the hardened gummosis lumps and decayed cortex on the main trunk and main lateral branches, then applying fungicide to the branches and trunks, with the purpose of cleaning the orchard and disinfecting it. In spring, after the peach trees bloom, the pesticide is sprayed several times; if gummosis has already occurred, the affected parts are first scraped and then coated.