"Aggressive" Frogs

Preceded by rice fields with co-existing crabs and ducks, the co-breeding rice planting is no news. In recent years, despite the efforts in experimenting "field multi-utilization", the farmers had not been able to discard the usage of pesticides and fertilizers and make the rice "organic". However, in early July this year, a breed called tiger frog in China's Fujian Province inspired the agric-tech specialists that frogs, which feed on pests in rice fields, are pests' natural enemies, while frog excrements are ideal organic fertilizers.

The tiger frog of Fujian origin is a crossbreed of wild tiger frogs of the Yangtze Delta and the home-raised frogs from Hainan Province. Smaller than bullfrogs and larger than ordinary frogs, it has a natural ferocity with an exceptionally sharp eyesight and bouncing capacity. Tiger frogs tend to inhabit such places as paddy fields, ponds, trenches and riverside weeds, where they stalk some 30 species of rice-prone insects, including pyralid moths, rice skippers, rice locusts, mole crickets, crickets and leafhoppers. They can also live on artificial compound feed, hence their nickname "Crop Guardians".

Fragrant rice, strong frogs, zero pesticide

When the rice first sprouted this summer, the Qingpu Agric-Tech Incubation Center introduced 54 thousand little tiger frogs into the 18-mu paddy field, each two mu of which were surrounded along the ridges by 1-meter-odd-high nets preventing the fleeing of grown frogs.

Thanks to the frogs, the rice grows naturally and easily. Compared with ordinary paddy fields, the rice-frog type requires no additional field operation, let alone fertilization, weeding or pesticide usage. According to statistics, one tiger frog can eat up to 260 or more insects a day or 10,000 a year. Consequently, a benign circulation of natural and organic biological chain occurs in the rice-frog field with rice feeding frogs and frogs protecting rice, and for each mu's fertilization, the amount of chemical carbamino, phosphate fertilizers and potash fertilizers is reduced by 100kg, 25kg and 15kg, respectively.

After three or four months of "interactivity" between rice and frogs, the rice has witnessed strong growing momentum with up to 360kg/mu productivity. What's more, with its organic and pesticide-free characteristics, the rice, which acquires continuous incremental value, has won the favor of citizens and farmers alike. On the other hand, the number of the tiger frogs trapped after the harvest has amounted to 240kg/mu, bringing income of above 3,840 yuan/mu against the background of a soaring market.

Method to be promoted next year

Currently, facilities like winter-resisting ponds, oviposition ponds, incubation ponds and tadpole ponds are successively constructed at the side of the rice-frog fields. Vice Director Xue Qinqin of the Qingpu Modern Farmland Agric-Tech Incubation Center, told reporters that the rice-frog field practice, with its twofold benefits of reducing agric-ecological pollution and increasing farmers' income, will be implemented in five or six hundred paddy fields next year before adopted by every household.

Meanwhile, Qingpu has mapped out its plan, which includes: establishing a rice-frog producer's cooperative, forming a production chain and establishing a tiger frog hatching base. In addition, the District plans to work for the frogs' instant freezing, cold storage and processing, and to further promote the "mutual help" between rice and frogs in the fields. According to the plan, 1,000 high-density and 9,000 medium-and-low-density frog and rice planting is to be promoted in the next three years to provide Qingpu's "Ten-thousand-mu Organic Rice" project with technical support packages.