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THE AMERICAN CHESTNUT PROJECT
进展报告 2021

Moving Closer to 10,000 Trees

Activities undertaken between November 1, 2020 and November 30, 2021

今年是令人兴奋的一年，达林美洲板栗收获最大. 这将使我们目前在田间试验中的树木总数增加到5165棵，其中2018棵 是达令58美洲栗树，以及它们的三代后代， that are being reviewed by the U.S. federal regulators for release to the public and forest restoration programs. 因此, even with the continued challenges from the 包括供应链延迟和额外的安全协议， 感谢您一直以来对我们工作的支持，这一年我们的工作仍然卓有成效 研究小组. Although we have had many research accomplishments (see publication 为使本年度的报告简明扼要，我们将重点介绍 the tree diversification, production, and the regulatory progress.

异交授粉和组织培养- Hannah Pilkey(生产经理)

这个授粉季节是一个特殊的一年，纳入新的母树 and pollen types to promote genetic diversity in the transgenic breeding plan. 下面 is a bulleted summary:

  • 丰富的花粉和丰富的开花季节使养团队得以发挥作用 the most controlled pollinations to date. In total, 5,378 viable nuts were harvested! This is a significant increase over last 一年 when 1,400 nuts harvested.
  • 在允许的地点对92棵板栗属母树进行授粉 in New York, compared to forty-one last 一年. Sixty of these 树 were American 栗. 在60种授粉的美洲栗树中，有27种是新开花的树，因此做出了贡献 to our diversification goals.
  • 我们的合作伙伴进一步实现了达令58的多样化和生产 at TACF that performed pollinations in ME, VT, IN, PA, VA, SC, and GA. 一些 与TACF抗疫霉根腐病(Phytophthora root rot, PRR)回交树杂交 来测试我们是否能在后代身上积累抗枯萎病和抗PRR的能力.
  • 采用不同背景的10种转基因花粉进行试验 pollinations and produced predominantly T3 seeds. One of the pollen types produced 缅因州博士. Tom Klak, D58+20USU45.5, was an early flowering T3 tree from last 一年. 该花粉类型产生28个活果，产生第一代T4. 这一加速花粉生产的成果发表在TACF的《网赌平台》秋季刊上 杂志.
  • 主要在纯美洲板栗母树上传粉 恢复的目标，但今年我们有足够的花粉来控制授粉 其他castania种和有趣的农业品种，包括阿勒格尼 chinquapin, Bouche de Betizac混血，Luvall的Monster混血，Bill的Chinese混血 hybrid, to name a few. 的se may help in future areas of agricultural American 栗 hybrid restoration, another value of the American 栗 树.
  • 近200个坚果是由Ozark Chinquapin母树和 亲爱的58花粉. 的se nuts will begin our plan to breed OxO into blight susceptible 帮助恢复这种同样遭到破坏的近亲物种 by the 栗 blight.
  • 发送了第一批使用冷冻野生型栗子花粉的实践授粉试剂盒 out this 一年 to a handful of citizen scientist volunteers. This was in anticipation of 亲爱的58花粉 shipment following deregulation. Every participant produced viable nuts and provided valuable feedback for future pollen shipments. To learn how to pollinate 以及如何参与，请观看我们的虚拟授粉 车间: American Chestnut Restoration Project - Pollination Workshop
  • 从组织培养实验室，200多棵T2树被无性生产，其中许多 went into holding plots for future distribution. In addition to many American 栗 我们的第一批美洲/欧洲杂交品种也进行了田间繁殖 测试. European 栗 is also susceptible to blight and this is a first step to bringing the OxO gene into that species.
  • 从2020年控制杂交中成功获得了13个新的、多样化的基因型 initiated into tissue culture. Two of these cultures include the first T1s of the 伤口/病原体诱导启动子系有助于靶向OxO的表达 the infection sites. We hope that some of these cultures will become pollen parents for the 2022 pollination season

Hanna Pilkey's instructions on pollination. Pollinating 雌花图1. Hanna Pilkey's instructions on pollination.

Patricia and Kaitlin harvesting 栗Sarah and Kyra on a bucket lift bagging 雌花

图2. 左:帕特里夏·费尔南德斯(博士后)和凯特琳·布雷达(行政助理)正在收割. 右图，Sarah Meisner和Kyra LoPiccolo(本科生)在铲斗升降机上装袋 雌花.

American 栗s harvestedhigh light growth chambers rapid pollen production

图3. Left, American 栗/Bouche de Betizac hybrid nuts as example of harvest. Right, High-light growth chambers rapid pollen production.

Regulatory Progress (Bill 鲍威尔, Professor and Chestnut Project Director)

比尔·鲍威尔签署美国环保署的请愿书、环保署的注册和环保署的咨询

 

无论我们在研究或生产上取得多大的进步，每个人都一样 question, when can we get some of the "Darling" American 栗 树? 这已经 这是一个很难回答的问题，因为我们正在与三个监管机构合作 在美国.S. (and soon two in Canada). In the past the regulators could only tell us the "typical" timelines for approval. 的n they say, the American 栗 isn't typical. 这将是第一个利用生物技术开发的修复树. But it won't be the last. 的 Darling American 栗 树 will pave the way to 拯救许多其他濒危树种，如美洲榆树等. 因此, the regulators are being extra careful and giving our 树 extensive review. 的 可爱的美洲栗树将是研究最多的树木品种之一 历史. 通过这样做，它将使未来恢复树木更容易和更快 因为监管者会更熟悉恢复的发展 树.

的 good news is we are finally getting decision dates in writing. 美国农业部的请愿书 was submitted on 1/17/2020 (just before COVID hit). We went through two public open 在最后的公告中，他们写下了他们期待工厂的时间 完成有害生物风险评估(PPRA)和环境影响报告书(EIS) 并作出决定，“我们计划在6个月内完成PPRA，以及环境影响报告书和 record of decision (ROD) within 2 一年s of the date of this notice. 这个时间表 is tentative and subject to extension." So that would put the PPRA around February 2022 and the ROD around August 2023.

在完成EPA要求的额外实验后，我们提交了19卷 (4,525页)注册并豁免于21年9月28日向EPA申请公差. 这将启动一个强制性的审查时钟，并被告知这将完成 12月. 2022. In parallel, we are submitting a petition for a 25b exemption from FIFRA following a process suggested by the EPA regulators. We expect to submit this petition next quarter which starts the parallel review process. 的 two reviews will have shared 信息，但是独立的结果，我们可以开始分配树 the registration, while waiting on the 25b exemption.

在与FDA进行多次讨论并完成他们要求的实验后， we submitted our consultation document on 10/27/21. We expect this review process to take about a 一年. In addition, we are submitting a separate petition to be exempt 从小麦食品标签规则中我们只添加了一个基因 will be submitting after a couple more experiments they requested.

所以，总而言之，我们希望有所有的监管决定需要分销 to the public by the 2023年秋天. 祈祷. My team and I appreciate our supporter's patience and encouragement to keep going through this long process. 的 树 are coming!

Publications this 一年

  • 卡尔森、埃里克、克里斯汀·斯图尔特、凯瑟琳·拜尔、琳达·麦圭根、托比·卡尔佩珀二世、 和威廉·鲍威尔. 2021. Pathogen-induced expression of a blight tolerance transgene in American 栗. Molecular Plant Pathology. (新闻)
  • Klak, Thomas, Ellen Spiers, 和威廉·鲍威尔. 2021. Transgenic Pollen in Less Than 一年. 栗杂志. 2021年秋季的问题.
  • 安德鲁·纽豪斯.安娜斯塔西娅·E. Allwine, Allison D. 奥克斯，达科塔F. 马修斯,斯科特 H.McArt, 和William A. 鲍威尔. 2021. Bumble Bee (Bombus Impatiens) Survival, Pollen 草酸氧化酶在实际浓度下的使用和繁殖不受影响 in American Chestnut (Castanea Dentata) Pollen. Transgenic 研究: http://doi.org/10.1007/s11248-021-00263-w.
  • 纽豪斯,. 和W. 鲍威尔 (2021) "Intentional introgression of a blight tolerance 转基因拯救美洲板栗残余种群>，《博彩平台》 and Practice 3(4):e348. http://conbio.onlinelibrary.wiley.com/doi/full/10.1111/csp2.348