RAPID: Testing macronutrient imbalance as a key factor limiting range expansion in herbivores

RAPID：测试宏量营养素不平衡是限制食草动物活动范围扩大的关键因素

• 批准号: 1826848
• 负责人: Arianne Cease
• 金额: $ 12万
• 依托单位: Arizona State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-05-01 至 2020-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1826848&HistoricalAwards=false
• 关键词: RAPID; Testing; macronutrient; imbalance; key

Insect outbreaks are common in nature and locust outbreaks are particularly dramatic due to their tremendous ecological and agricultural impacts. Occasionally, insect populations explode throughout broad geographic ranges, and then collapse back into their smaller permanent breeding zones within months or years. Neither the mechanisms of population expansions nor declines are well understood, but our knowledge of the declines is particularly poor. This is a major challenge in organismal biology and ecology, with significant implications for human society. This research project will take advantage of an ongoing outbreak of the South American locust (Schistocerca cancellata) to test the hypothesis that the ability for S. cancellata to attain a balance of nutrients optimal for growth limits their capacity to maintain persistent high populations over broad regions of South America. Locusts are a major challenge for food security globally, with outbreaks causing 80-100% crop losses. In the future, working collaboratively with government plant protection agencies, this research can be directly applied to strategies to improve livelihoods, human and environmental health, and global food security. Moreover, this award will support postdoctoral and student training, and cross-cultural exchange. The South American locust (Schistocerca cancellata) is experiencing its largest population upsurge in 60 years, expanding beyond its permanent breeding zone in northwest Argentina into a much larger part of Argentina and beyond into Bolivia and Paraguay, causing national emergencies in those three countries. One hypothesis for why S. cancellata do not persist at high densities in their invasion zone, which is supported by preliminary data, is that S. cancellata in their expansion zones are unable to obtain food of sufficiently high carbohydrate:protein ratio to maximize their fitness. This poor nutrition then leads to population decreases in their expansion zone. This carbohydrate insufficiency hypothesis will be tested in this project by: 1) assessing the plant macronutrient contents and feeding behavior of S. cancellata in the field at sites differing in median plant macronutrient ratios; 2) measuring the short-term effects of dietary macronutrient content on the performance of juvenile S. cancellata in the field, and 3) measuring the whole-lifetime effects of dietary macronutient content on the performance of S. cancellata in the lab under controlled environmental conditions. Together these experiments will test the mechanisms potentially responsible for fluctuations in locust populations in the recession and invasion zones.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

昆虫的爆发在自然界中很常见，蝗虫的爆发由于其巨大的生态和农业影响而特别引人注目。偶尔，昆虫种群在广阔的地理范围内爆炸，然后在几个月或几年内崩溃回到较小的永久繁殖区。无论是人口增长还是下降的机制都没有得到很好的理解，但我们对人口下降的了解特别少。这是生物学和生态学的一个重大挑战，对人类社会具有重大意义。这项研究计划将利用正在爆发的南美蝗虫（Schistocerca cancellata）来检验S。cancellata获得最佳生长的营养平衡限制了它们在南美洲广泛地区维持持续高种群的能力。蝗虫是全球粮食安全的主要挑战，其爆发造成80-100%的作物损失。在未来，与政府植物保护机构合作，这项研究可以直接应用于改善生计，人类和环境健康以及全球粮食安全的战略。此外，该奖项将支持博士后和学生培训以及跨文化交流。南美洲蝗虫（Schistocerca cancellata）正经历60年来最大的种群激增，从阿根廷西北部的永久繁殖区扩展到阿根廷更大的地区，并进一步扩展到玻利维亚和巴拉圭，在这三个国家造成全国性紧急情况。关于S. cancellata在其入侵区不以高密度持续存在，这一点得到了初步数据的支持，S.在它们的膨胀区中的cancellata不能获得足够高的碳水化合物：蛋白质比率的食物以使它们的适应性最大化。这种营养不良，然后导致人口减少，在他们的扩张区。本计画将借由下列方法来验证此碳水化合物不足假说：1）评估植物大量营养素含量与中华绒螯蟹摄食行为。在现场不同的植物常量营养素比例的中位数; 2）测量饲料常量营养素含量对青少年S。3）测定饲料中常量营养素含量对中华绒螯蟹生产性能的终生影响。在实验室中的受控环境条件下。这些实验将共同测试可能导致衰退和入侵区蝗虫种群波动的机制。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。