Rice is a staple food in many parts of the world. But planting is very labor-intensive: each year rice farmers tend for weeks and plant each seedling. International biologists and agronomists have therefore been investigating perennial variation for decades.
Biologists from Yunnan Chinese University presented such a variant to southern Chinese farmers for cultivation in early 2018. The new strain, called Perennial Rice 23 (perennial rice 23), comes from crossing an Asian rice variety with an African wild rice variety.
The US trade journal “Science” is currently publishing a study led by the Chinese geneticist and agronomist Fengyi Hu, showing the results of the harvest. It gives hope: For five years, biennial crops of PR23 plants yielded slightly more than traditional annual rice for four years: 8.8 tons per hectare – before the harvest collapsed in the fifth year and farmers had to plant new plants.
Less labor, less water, lower cost
Compared to annual rice, PR23 requires less fertilizer because more nutrients remain in the soil. Deeper roots also hold more water in the soil, preventing erosion.
Perennial rice also offers farmers financial advantages: The cost of gasoline for farming and seedlings is the same as for traditional rice only in the first year: the equivalent of about 2,600 francs per hectare. In the following years, fiscal spending is cut by more than half. And farmers save on working time: in subsequent years, one hectare needs between 68 and 77 days less time to sow.
The only downside: Insects multiply faster due to less intensive management – it remains to be seen if the PR23 needs more pesticides.
So overall good news. What the study doesn’t say is whether the rice tastes better, too. However, given the looming food shortages, this is likely negligible.