BEIJING, May 26 (AFP) - The World Bank's Board of Executive Directors has approved an aid package worth 250 million dollars aimed at boosting the incomes of China's poorest farmers, official media said Wednesday. The board approved a loan of 80 million dollars from the World Bank and a 20-million-dollar credit from the bank's International Development Association (IDA) for the Guanzhong Irrigation Improvement Project, Xinhua news agency reported. It also approved a 100-million-dollar loan and a 50-million-dollar IDA credit for the Second Loess Plateau Watershed Rehabilitation Project, it said. The Guanzhong project aims to increase grain production in nine irrigation areas, boosting farmers' incomes and strengthening irrigation management in the Guanzhong Plain of Shaanxi province, Xinhua said. The Second Loess project is to help achieve sustainable development by increasing agricultural production and incomes, and improving ecological conditions in tributary waters of the Yellow River. The areas to benefit are among the poorest in China, where people have almost no means of scratching a living from the barren land. The World Bank loans have a maturity of 20 years, including a five-year grace period, while the IDA credits have a maturity of 35 years, Xinhua added.  