seed and plant characteristics in response to herbivore treatment

In the experiment Sinapis arvensis plants were exposed to one of four treatment: no herbivory (=ct), healthy Pieris brassicae caterpillars (=Pier), caterpillars parasitized by the gregarious Cotesia glomerata (=Cot), and caterpillars parasitized by the solitary Hyposoter eneninus (=Hyp). Plants were initially grown in the greenhouse but at the onset of flowering, they were transferred to tents placed in a garden to which pollinators were added. At this time point, the plants were exposed to the treatments. The experimental unit was a tray with 6 plants (=replicate), There were 4 replicates per treatment. When insect development was completed, we counted 1) the number of undamaged seed pods and 2) the number of damaged seed pods. Plants were then transferred to a garden in which the control plants were already present. When the seedpods had matured and dried, they were collected. Seed pods that had grown additionally were collected one month later (=new seed pods). Seeds were separated from their pods and weighed (=total seed mass in g). Per plant, cohorts of 20 seeds were weighed and their mean was calculated (=mean individual seed mass in microgram). We calculated the number of seeds per plants by dividing the weight of all seeds produced by a plant by its individual seeds mass (=number of seeds). After 2 years of storage in the dark, germination success of the seeds was determined by randomly choosing 50 seeds from each plant and allow them to germinate on wet filter paper. Germination success was calculated as the fraction of seeds that germinated out of 50. Reproductive potential was then calculated as the product of seed number and germination success.
The data on the seed characteristics are in the ‘seed data per tray’ sheet, individual seed mass are in the sheet ‘seed mass of individual seeds) and the data on the seed pods are in ‘seed pods’ sheet.

本实验以田芥菜（Sinapis arvensis）为供试材料，共设置4种处理方式：无植食处理（=ct）、健康菜粉蝶（Pieris brassicae）幼虫处理（=Pier）、被群居性菜粉蝶绒茧蜂（Cotesia glomerata）寄生的幼虫处理（=Cot），以及被独居性横脊茧蜂（Hyposoter eneninus）寄生的幼虫处理（=Hyp）。植株初始于温室中培育，至开花初期被转移至置于花园内的网笼中，网笼内已接入传粉昆虫，此时施加对应处理。实验单元为包含6株植株的托盘（即重复单元），每种处理设置4个重复。当供试昆虫发育完成后，统计两项指标：1）未受损荚果数量；2）受损荚果数量。随后将植株转移至已定植对照植株的花园中。待荚果成熟干燥后进行采收；额外生长出的荚果则于一个月后采收，记为新生荚果。将种子从荚果中分离并称重，记为总种子质量（单位：克）。每株植株选取20粒种子为一组进行称重，计算其平均值，记为单粒种子平均质量（单位：微克）。通过将单株植株所结全部种子的总质量除以单粒种子平均质量，计算得到单株种子总数。将种子于黑暗条件下贮藏2年后，从每株植株的种子中随机选取50粒，置于湿润滤纸上开展萌发实验，以萌发种子数占所选取50粒种子的比例计算种子萌发成功率。最终以单株种子总数与种子萌发成功率的乘积计算植株繁殖潜力。本数据集的种子特征数据存储于"seed data per tray"工作表中，单粒种子质量数据存储于"seed mass of individual seeds"工作表，荚果相关数据存储于"seed pods"工作表中。