A shortage in the supply of a number of farm products like garlic, green beans and corn has partly led to rising prices, the Ministry of Agriculture said on Friday.

The price of green beans and garlic has tripled in the past weeks, business portal China Food Network reported.

Green beans are selling for about 20 yuan ($2.9) a kg and garlic is selling for about 10 yuan a kg, the network reported.

But the average price of 28 vegetables monitored by the authorities has continuously decreased for the past three weeks, latest figures from the ministry showed.

The supply of green beans and garlic has plunged because of lower production and increasing exports, said Ma Shuping, deputy director of the ministry's crop farming department.

Green bean production alone was hit by bad weather, decreasing by more than 130,000 tons last year, Ma said. At the same time, 230,000 tons more of the produce were exported amid falling imports, she said.

Domestic supply of green beans fell by at least 400,000 tons last year, she said.

"Besides the supply shortage, more people are drinking green bean soup on hot days in line with health trends and that helps drive up prices," Ma said.

Hoarding in garlic and green beans has also helped push up their prices because the products can be stored for longer periods of time, said Sui Pengfei, inspector of the ministry's market information division.

"But the hoarding will not spread to other farm products and cause higher inflation, because we have a supervision system for major farm products like beans, pork and sugar," Sui said.

Earlier this week, the National Development and Reform Commission (NDRC), the country's top economic planner, pledged to crack down on the hoarding of farm products and curb rising food prices. It is the third time in the past two weeks that the commission has addressed the importance of checking rising prices.

Temporary intervention to stabilize prices is necessary and any one found to be involved in serious price manipulation may face criminal punishment, NDRC regulators said.

China's inflation rate, or the consumer price index, jumped 2.8 percent in April, mainly fueled by the prices of farm products. The country's inflation target for this year is 3 percent.

The NDRC and the Ministry of Agriculture said an improved system will be set up for supervising prices to keep tabs on any price fluctuations.

Land for vegetable cultivation hit about 8 million hectares with a year-on-year increase of 6.7 percent, latest statistics from the Ministry of Agriculture showed.