本帖最后由 远航一号 于 2023-2-21 01:43 编辑
https://www.science.org/content/article/breakthrough-2022
多年生水稻有望使农业更容易由埃里克·斯托克斯塔德(https://www.science.org/content/author/erik-stokstad)
通过使季节性重新种植变得不必要，多年生水稻每年可以为农民节省数周的辛勤工作。
COSTFOTO/FUTURE PUBLISHING/GETTY IMAGES
世界上主要的粮食作物——水稻、小麦、玉米——每次收获都必须重新种植。这对农民来说是很多工作，并可能导致土壤侵蚀等环境问题。年复一年地存活和生产的多年生谷物可以减轻负担，但培育长寿和足够多产的植物一直是一个挑战。今年，中国的研究人员表明，多年生水稻可以达到这些基准(https://www.science.org/content/ ... d-money-comes-risks)，并为农民节省数周的辛苦劳动。 该品种被称为多年生水稻23（PR23），是多年前通过将亚洲水稻的商业品种与生长在非洲的多年生野生稻杂交而成的。提高产量和质量花了 2 多年的时间。最后，在2018年，云南大学和其他机构的研究人员向中国的农民发布了PR23，让他们进行了一项大规模实验，以了解水稻可以收获多少次，并测量产量和其他效益。 PR23的谷物产量与常规季节性种植的水稻一样多(https://www.nature.com/articles/s41893-022-00997-3)，该团队上个月在Nature Sustainability上报道。第一年，种植和栽培成本大致相同。但在第二年，农民可以消除一项重大任务：将嫩稻幼苗移植到稻田中，这通常是妇女和儿童完成的艰苦工作。由于多年生水稻，跳过这一步，每个季节每公顷的工作量减少了多达77人日，并帮助农民的成本降低了一半。多年生水稻田的土壤养分也有所增加。然而，到了第五年，产量下降得如此之多，多年生水稻需要重新种植。 越来越多的农民正在种植PR23，这要归功于云南大学的技术援助和政府的推动。去年，中国南方的种植面积超过15，000公顷，比2020年增加了四倍。PR23和类似品种也正在非洲进行测试(https://ricetoday.irri.org/peren ... -changer-in-africa/)。多年生水稻还可以减少东南亚梯田高地的水土流失。但植物育种者仍然需要开发一种适应该环境干燥和更不肥沃的土壤的菌株。研究人员还担心长期影响。一个问题是杂草和病原体会积聚在未犁过的田地里，需要比传统水稻更多的除草剂。另一个问题是大米是否排放更多的一氧化二氮 - 一种强大的温室气体。但随着种植的普及，多年生水稻的成本和效益应该成为焦点。
==== 以下为英文原文 ====
Perennial rice promises easier farming BY ERIK STOKSTAD An overhead photo of people raising and planting rice seedlings in a field. By making seasonal replanting unnecessary, perennial rice could save farmers weeks of hard work each year.COSTFOTO/FUTURE PUBLISHING/GETTY IMAGES The world’s major food crops—rice, wheat, corn—must be planted anew for every harvest. That’s a lot of work for farmers and can contribute to environmental problems such as soil erosion. Perennial grains that survive and produce year after year could ease the burden, but breeding plants that are long-lived and productive enough has been a challenge. This year, researchers in China showed perennial rice can meet those benchmarks and save farmers many weeks of backbreaking labor.
Called Perennial Rice 23 (PR23), the variety was created years ago by crossing a commercial variety of Asian rice with a perennial wild rice that grows in Africa. Improving its yield and quality took more than 2 decades. Finally, in 2018, researchers at Yunnan University and other institutions released PR23 to farmers in China, enlisting them in a large-scale experiment to find out how many times the rice can be harvested and measure the yield and other benefits.
PR23 yielded just as much grain as regular, seasonally planted rice, the team reported last month in Nature Sustainability. In the first year, planting and cultivation cost about the same. But in the second year, farmers could eliminate a major task: transplanting young rice seedlings into a paddy, grueling work often done by women and children. Skipping this step, thanks to the perennial rice, reduced the amount of work per hectare by as much as 77 person-days each season, and helped lower farmers’ costs by half. Soil nutrients also increased in the fields containing perennial rice. By the fifth year, however, yields dropped so much the perennial rice needed to be replanted.
More and more farmers are cultivating PR23, thanks to technical assistance from Yunnan University and government promotion. More than 15,000 hectares were planted in southern China last year, a fourfold increase from 2020. PR23 and similar varieties are being tested in Africa as well. Perennial rice could also reduce soil erosion in the terraced uplands of Southeast Asia. But plant breeders still need to develop a strain adapted to that environment’s drier and less fertile soil. Researchers also worry about long-term impacts. One concern is that weeds and pathogens will accumulate in the unplowed fields, requiring more herbicide than conventional rice does. Another question is whether the rice emits more nitrous oxide—a potent greenhouse gas. But as cultivation spreads, the costs and benefits of perennial rice should come into focus.
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发表于 2023-2-21 00:31:20
