ORIGINAL RESEARCH article

Front. Hortic.

Sec. Breeding and Genetics

Volume 4 - 2025 | doi: 10.3389/fhort.2025.1603031

This article is part of the Research TopicHorizons in HorticultureView all articles

Rootstock impacts on 'USDA-ARS-Pawnee' pecan growth, physiological traits, and soil microbial communities

Provisionally accepted
Xinwang  WangXinwang Wang1*Keith  KubenkaKeith Kubenka1Warren  ChatwinWarren Chatwin1Angelyn  HiltonAngelyn Hilton1Braden  TondreBraden Tondre1Tingying  XuTingying Xu2Lu  ZhangLu Zhang2
  • 1Southern Plains Agricultural Research Center, Agricultural Research Service (USDA), College Station, United States
  • 2Oklahoma State University, Stillwater, Oklahoma, United States

The final, formatted version of the article will be published soon.

Pecan (Carya illinoinensis), native to North America, is the most commercially important species within the Carya genus. Central to nut production across the southern United States, pecans are cultivated for their premium-quality nuts used in various culinary applications. The increasing global demand for pecans has emphasized the need for improved cultivation practices to ensure both economic viability and sustainability. This study examined the impact of 12 different rootstocks on the growth and physiological characteristics of the 'USDA-ARS-Pawnee' scion across multiple years. Key traits assessed included budbreak timing, tree morphology, leaf size, leaf retention, photosynthesis, leaf nutrient content, and soil microbial community composition. Significant differences in budbreak timing were observed among the rootstocks, with northern rootstocks, particularly Peruque, exhibiting the latest budbreak, while eastern rootstocks showed the earliest. Regarding tree growth, southern (Mexican) rootstocks significantly outperformed northern rootstocks in terms of scion plant height, trunk diameter, and canopy width. Rootstocks from the southern regions demonstrated superior growth, highlighting the potential for selecting Mexican rootstocks to enhance pecan tree size in orchards. Leaf size showed variation across rootstocks, with northern and eastern rootstocks producing larger leaves, although these differences were not statistically significant. Lager leaf is positively correlated with higher photosynthesis rate (PSR) and water use efficiency (WUE). 'Giles' (northern) and 'VC1-68' (western) had the highest PSR and WUE, while Elliott (eastern) exhibited the lowest PSR and WUE. Leaf retention did not differ significantly across rootstocks, but northern and eastern rootstocks retained more leaves into early November compared to southern and western rootstocks. Nutrient analysis revealed that most leaf nutrients varied across the 12 rootstocks but were not significantly influenced by rootstock origins. 'Riverside' had the highest Zn content, while 'Peruque' had the lowest. Similarly, 'Major' exhibited the highest B content, and 'Frutoso' had the lowest. Soil microbial analysis revealed differences in microbial composition between the rootstocks, with 'Peruque' promoting ectomycorrhizal fungi and 87MX5-1.7 supporting nitrogen-fixing bacteria, indicating that rootstocks can influence soil microbial diversity and nutrient cycling. These results highlight the importance of rootstock selection for improving tree vigor, photosynthetic efficiency, and soil health in pecan orchards.

Keywords: Carya illinoinensis, provenance, Seedstock, scion, Horticultural traits, microbial community

Received: 31 Mar 2025; Accepted: 04 Jun 2025.

Copyright: © 2025 Wang, Kubenka, Chatwin, Hilton, Tondre, Xu and Zhang. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence: Xinwang Wang, Southern Plains Agricultural Research Center, Agricultural Research Service (USDA), College Station, United States

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