Abstract

The red sunflower seed weevil, Smicronyx fulvus L., is a univoltine seed-feeding pest of cultivated sunflower, Helianthus annuus L. Artificial infestations of S. fulvus onto sunflowers with traditional (<25% oleic acid), mid-oleic (55–75%), or high oleic (>80%) fatty acid profiles were used to test if fatty acids could be used as natural markers to estimate the proportion of weevils developing on oilseed sunflowers rather than wild Helianthus spp. and confection (non-oil) types. Oleic acid (%) in S. fulvus confirmed the fatty acid compositions of mature larvae and weevil adults reflected their diets, making primary (oleic or linoleic) fatty acids feasible as natural markers for this crop-insect combination. Oleic acid in wild S. fulvus populations in North Dakota suggests at least 84 and 90% of adults originated from mid-oleic or high oleic sunflower hybrids in 2017 and 2018, respectively. Surveys in 2017 (n = 156 fields) and 2019 (n = 120 fields) extended information provided by S. fulvus fatty acid data; no significant spatial patterns of S. fulvus damage were detected in samples, damage to oilseed sunflowers was greater than confection (non-oil) types, and the majority of damage occurred in ≈10% of surveyed fields. Combined, data suggest a few unmanaged or mismanaged oilseed sunflower fields are responsible for producing most S. fulvus in an area. Improved management seems possible with a combination of grower education and expanded use of non-insecticidal tactics, including cultural practices and S. fulvus-resistant hybrids.

中文翻译：

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脂肪酸数据和作物调查显示了红色向日葵种子象鼻虫（鞘翅目：Curculionidae）的来源，种群以及建议的管理策略

摘要

红色向日葵种子象鼻虫Smicronyx fulvus L.是栽培向日葵向日葵的单伏种子进食害虫。在传统油酸（<25％油酸），中等油酸的向日葵上人工感染S.fulvus 。75％）或高油酸（> 80％）脂肪酸谱用于测试脂肪酸是否可以用作天然标记，以估计油料向日葵而非野生向日葵上发育的象鼻虫的比例。和糖果（无油）类型。油酸（％）在S.茅证实成熟幼虫和象鼻虫的脂肪酸组成反映了他们的饮食，使伯（油酸或亚油酸）脂肪酸可作为这种农作物昆虫组合的天然标记物。北达科他州野生黄花葡萄球菌种群中的油酸表明，分别在2017年和2018年至少有84％和90％的成年人起源于中油酸或高油酸向日葵杂交种。2017年（n = 156个字段）和2019年（n = 120字段）的调查扩展了由S.fulvus脂肪酸数据提供的信息; 黄花苜蓿无明显的空间格局在样品中检测到损坏，对油料向日葵的损坏大于甜食（非含油）类型，并且大多数损坏发生在约10％的调查田间。总体而言，数据表明，少数未处理或处理不当的油料向日葵田是该地区产生大多数黄花链霉菌的原因。结合种植者教育和扩大使用非杀虫策略（包括文化习俗和抗黄腐病菌的杂交种），似乎有可能改善管理。