The Taiwan Agricultural Research Institute, under the Ministry of Agriculture, has tested biodegradable plastic films in sweet potato production to address yield constraints linked to climate conditions.
Sweet potatoes in Taiwan are exposed to drought and low temperatures during autumn and winter, affecting production levels. The use of plastic films is aimed at maintaining soil moisture and increasing soil temperature, while also reducing the need for weeding and additional fertilisation.
Field trials compared uncovered crops with those covered by conventional and biodegradable plastic films. Under the same conditions, uncovered plants yielded 11,000 kg per hectare. Crops covered with conventional plastic films produced 2.5 times more, while those using biodegradable films achieved nearly three times the yield.
The cost of biodegradable film is about NT$82,000 (US$2,624) per hectare. Despite this, the method increases returns by around NT$60,000 (US$1,920) per hectare compared to standard cultivation practices.
After harvest, the films can be recycled or incorporated into the soil, where they decompose.
According to the Agriculture and Food Agency, domestic demand for sweet potatoes is about 230,000 tons annually, while production is around 218,000 tons. Imports reached 2,142 tons last year, mainly from Vietnam and Japan.
Sweet potatoes are grown across approximately 10,000 hectares in Taiwan, with production concentrated in Yunlin, Changhua, Taichung, and Tainan. Shuilin Township in Yunlin accounts for about 20 per cent of the total output.
The crop has an annual value exceeding NT$3 billion (US$96 million). Tainung No. 57 is one of the varieties cultivated in the region, used in processed products due to its starch content and cooking characteristics.
Source: Taiwan News
