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Raineri, J.

Publications and source records attributed to Raineri, J..

3 recordsLinked to original sources

Isogenic reciprocal grafts with transgenic HaHB11 plants dissect shoot and root contributions to yield in field-grown soybean: a multi-omic study

Soybean must coordinate root and shoot signals to optimize yield. Grafting is a powerful tool to study this communication. However, most studies compare contrasting genotypes and cannot separate genotype from graft combination effects. Here we used isogenic soybean lines to dissect root and shoot contributions in the field. These lines differ from controls in a single gene, either HaHB11 or HaHB4, two sunflower HD-Zip I transcription factors associated with increased grain number. Unexpectedly, heterografted plants outperformed homografts in several yield-related traits, an effect not previously documented in soybean. This advantage was reproduced with both HaHB11 and HaHB4 scions, suggesting the effect is not gene-specific. Under non-stress conditions the scion governed yield-related traits, particularly pod number, as well as the leaf transcriptome, whereas both organs left subtle metabolic signatures. The root contribution was minor and confined to the R6-R7 transition, where it was specific to HaHB11. The highest-yielding combination was a control rootstock with an HaHB11 scion (CH11), which increased grain number by [~]30% over the best homograft. CH11 showed higher stomatal conductance and lower leaf temperature; yet CH11 and HaHB11 homografts were remarkably similar, sharing higher stomatal density, differing in only four leaf-expressed genes, and lacking a metabolomic signature. Thus, under non-stress conditions, soybean grain number is governed by the scion and the graft combination, and accompanied by early physiological differences rather than by leaf molecular reprogramming.

plant biology↗

Field-tested HaHB11 and HaHB4 soybean exhibit increased grain number and heat tolerance at the reproductive stage

Soybean is one of the primary sources of vegetable oil and protein worldwide. However, its yield improvement has lagged behind the other major crops. This study explored the potential of the sunflower transcription factor HaHB11 to enhance soybean yield and heat stress tolerance. We generated transgenic soybean plants expressing HaHB11 and evaluated their performance across four field trials. The HaHB11 plants showed a significant increase in grain number per plant compared to controls, which can be related to an increased number of nodes and pods per plant. Flowering dynamics analysis revealed delayed blooming and an increased number of flowers per node, leading to a higher pod set, particularly between nodes four and six. Principal component analysis across field trials identified temperature as a crucial factor influencing grain number, enhancing the differences exhibited by HaHB11 plants. The pollen from transgenic plants germinated better, and tubes were longer than controls under heat stress. Carbohydrate distribution analyses indicated differential allocation of nutrients, supporting the increased pod and grain set in HaHB11 plants. Additionally, vegetation indices can distinguish HaHB11 plants from controls in several developmental stages. These results indicated that HaHB11 enhances soybean yield under heat stress, becoming a promising technology for soybean improvement. HighlightSoybean transformed with the sunflower gene HaHB11 was tested in the field for four campaigns, showing differential allocation of nutrients, increased number of nodes, pods, grains, and heat tolerance.

plant biology↗

HaHB11 transformed maize has improved yield under waterlogging and defoliation in control and field conditions

HaHB11 is a sunflower transcription factor previously described as conferring improved yield to maize hybrids and lines. Here we report that transgenic HaHB11 maize lines exhibited a better performance funder waterlogging, both in greenhouse and field trials carried out during three growth cycles. One of these trials was particularly affected by a strong storm during flowering, causing severe defoliation. Controlled defoliation assays indicated that the transgenic genotypes were able to set more grains than controls. Hybrids were generated by crossing B73 HaHB11 lines with the contrasting Mo17 lines and tested in the field. These hybrids exhibited the same beneficial traits as the parental lines when compared with their respective controls. Waterlogging tolerance coursed via the root architecture improvement, including more xylem vessels, reduced tissue damage, less superoxide accumulation, and altered carbohydrate metabolism compared to controls. Multivariate analyses corroborated the robustness of the differential traits observed. Furthermore, canopy spectral reflectance data, computing 29 vegetation indices associated with biomass, chlorophyll, and abiotic stress, helped to identify genotypes as well as their growing conditions. Altogether the results reported here indicate that this sunflower gene constitutes a suitable tool to improve maize plants for environments prone to waterlogging and/or wind defoliation. One sentence summaryPhenotyping and big data analyses indicate that the transcription factor HaHB11 confers waterlogging and defoliation tolerance, and increased yield to maize lines and hybrids in all tested conditions.

plant biology↗