The general aim of this project is to generate information that can be used in breeding programs to increase the yield potential of high grain protein rice content . The study of the physiological responses in the different stages of rice crop at suboptimal temperatures will provide information and tools to increase productivity. The latter, added to the characterization of the ideotype and the yield components, constitute the basis for developing germoplasm with better agronomic aptitude and grain quality for the Argentine rice zone.

6.5 Tn/ha is the current yield of rice in Argentina, a value that still i is distant from the potential yield that is estimated to be above 12 Tn/ha and up to a maximum of 14-15 Tn/ha. This difference between current and potential yield is associated with the negative influence of different vulnerability factors for rice, and one of the most important, with direct influence on yield, is represented by thermal deficiencies or moderately low temperatures from the early to the late vegetative phase. Given that low temperatures coincide with the early and also advanced vegetative phase, its greatest effect is the decrease in the development and survival of plants in the seedling stage. These thermal deficiencies are a normal characteristic of an important portion of the total rice-growing area, particularly in the central-southern area of ​​​​the Province of Entre Ríos, where 45% of the sown area is concentrated. Despite that, these rice areas have sufficient soil-water-light resources to obtain higher yields than the current ones. Therefore, the rice plants with tolerance to low temperatures would allow overcoming this limitation of the expansion of the rice area.
Despite the above, the current local market, and even the regional one, offers cultivars with good yields but sensitive to low temperatures, which forces a delay in planting dates, which consequently positions the reproductive phase in a period with lower light and thermal resources.
Taking into account the above, the improvement of rice through the introduction of germoplasm with high tolerance to low temperatures would have a dual purpose. On the one hand, it would improve the survival and development of plants during the reproductive phase. On the other hand, it would make it possible to advance the planting date to relocate the reproductive phase in periods of maximum resources, which would have a positive impact on yield.

It is then that the improvement of rice through the introduction of improved cultivars represents the general objective of this project, on which progress has already been made in this regard through the generation of a Dual Selection System for high tolerance and yield, through the application of tools from the knowledge of the responses of rice plants grown under cold stress conditions.

Zinc (Zn) is an essential element for the growth and development of plants. In Argentina, the provision of this element has decreased over the years, mainly due to agricultural intensification and low use of fertilizers, leading to situations of nutrient deficiency in various crops such as rice. In addition, soils with high pH and the presence of carbonates, combined with high zinc harvest index with little or no replacement, have exacerbated the problem of zinc deficiency. Furthermore, in the central-southern rice-growing region, in addition to the scarcity of this element, the crop is affected by low-quality irrigation water and episodes of low temperatures in the early stages. Currently, zinc deficiency is mitigated by fertilizations carried out by vehicleizing the nutrient in seed applications, limiting the amounts provided and the correction of deficiencies. Therefore, this project proposes to isolate and identify zinc-solubilizing bacteria that promote rice growth and mitigate the adverse effects of abiotic stresses such as salinity and low temperatures.

Michelini MC, Gazquez A, Checovich ML, Salazar Tamayo A, Maiale SJ, Menéndez AB, Rodríguez AA. Determination of low-temperature stress during the vegetative stage as a tool to predict plant yield in rice genotypes with contrasting tolerance levels. Journal of Agronomy and Crop Science 210, e12670. 2024. http://www.https//doi.org/10.1111/jac.12670

Michelini MC, Gazquez A, Checovich ML, Salazar Tamayo Andy, Maiale SJ, Menéndez AB, Rodríguez AA. Determination of low-temperature stress during the vegetative stage as a tool to predict plant yield in rice genotypes with contrasting tolerance levels. Journal of Agronomy and Crop Science. En prensa. https://doi.org/10.1111/jac.12670

Rodríguez AA, Vilas JM, Sartore GD, Bezus R, Colazo J, Maiale SJ. Field and genetic evidence support the photosynthetic performance index (PIABS) as an indicator of rice grain yield. Plant Physiology and Biochemistry 201, 107897. 2023. https://doi.org/10.1016/j.plaphy.2023.107897

Suazo Castro BR, Martínez SB, Puig ML, Maiale S, Garbi M. Período de cosecha y producción de tomate (Solanum lycopersicum L.) injertado y conducido a más de un eje, bajo invernadero. Chilean Journal of Agricultura & Animal Sciences 39, 23-34. 2023. https://doi.org/10.29393/CHJAA39-3PCBM50003

Duhalde MA, Bezus R, Rodríguez AA, Maiale SJ, Romero FM.  Optimization of tissue culture conditions and in vitro and in planta transformation of the local variety of rice Don Justo FCAyF. Revsita Facultad Agronomía, Biotecnologías Aplicadas a Cultivos de Interés Socioeconómico 121, 1-13. 2022. https://doi.org/10.24215/16699513e100

Maguire VG, Rodríguez AA, Ezquiaga JP, Salas N, Gortari M, Ayub N, Bouilly PJ. Romero MF, Gárriz A, Ruiz OA. Analysis of the contribution of Lotus corniculatus to soil carbon content in a rice-pasture rotation system. Agriculture, Ecosystems and Environment 340, 108159. 2022. https://doi.org/10.1016/j.agee.2022.108159

Cumpa-Velásquez LM, Moriconi JI, Dip DP, Castagno LN, Puig ML, Maiale SJ, Santa María GE, Sannazzaro AI, Estrella MJ. Prospecting phosphate solubilizing bacteria in alkaline-sodic environments reveals intra-specific variability in Pantoea eucalypti affecting nutrient acquisition and rhizobial nodulation in Lotus tenuis. Applied Soil Ecology 168, 104125. 2021. https://doi.org/10.1016/j.apsoil.2021.104125

Mantz GM, Rossi FR, Viretto PE, Noelting MC, Maiale SJ. Stem canker caused by Phomopsis spp. Induces changes in polyamine levels and chlorophyll fluorescence parameters in pecan leaves. Plant Physiology and Biochemistry 166, 761-769. 2021. https://doi.org/10.1016/j.plaphy.2021.06.050

Maguire V, Ezquiaga JP, Rodriguez A, Bouilly PJ, Gortari M, Gárriz A, Ruiz OA. Mediación biológica para el aumento del carbono y el nitrógeno orgánicos en el suelo. Proarroz 29-33. 2021.

Puig ML, Rodríguez AA, Vidal AA, Bezus R, Maiale SJ. Patterns of physiological parameters and nitrogen partitioning in flag leaf explain differential grain protein content in rice. Plant Physiology and Biochemistry 168, 457-464. 2021. https://doi.org/10.1016/j.plaphy.2021.10.034

Rodríguez AA. Taleisnik E. Soil Salinization and Sodification as Conditioners of Vegetation and Crops: Physiological Aspects of Plant Response to These Conditions. In Intensified Land and Water Use 43-54. 2021  https://doi.org/10.1007/978-3-030-65443-6_3

Gázquez A, Abdelgawad H, Baggerman G, Van Raemdonck G, Asard H, Maiale SJ, Rodríguez AA, Beemster GTS. Redox homeostasis in the growth zone of the rice leaf plays a key role in cold tolerance. J Exp Bot. 71: 1053-1066. https://doi.org/10.1093/jxb/erz455.

Pires N, Maiale S, Venturino A, Lascano C. Differential effects of azinphos-methyl and chlorpyrifos on polyamine oxidative metabolism during the embryonic development of Rhinella arenarum and its relation to oxidative stress. Pestic Biochem Phys. 163: 14-22. 2020. https://doi.org/10.1016/j.pestbp.2019.10.007

Bordenave CD, Granados Mendoza C, Jiménez Bremont JF, Gárriz A, Rodríguez AA. Defining novel plant polyamine oxidase subfamilies through molecular modeling and sequence analysis. BMC Evol Biol. 19: 28. 2019. https://doi.org/10.1186/s12862-019-1361-z

Bordenave CD, Rocco R, Maiale SJ, Campestre MP, Ruiz OA, Rodriguez AA, Menendez AB. Chlorophyll a fluorescence analysis reveals divergent photosystem II responses to saline, alkaline and saline–alkaline stresses in the two Lotus japonicus model ecotypes MG20 and Gifu-129. Acta Physiol Plant. 41: 167. 2019. https://doi.org/10.1007/s11738-019-2956-0

Gázquez A, AbdElgawad H, Baggerman G, Van Raemdonck G, Asard H, Maiale SJ, Rodríguez AA, Beemster GTS. Redox homeostasis in the rice leaf growth zone plays a key role in cold tolerance. J Exp Bot erz455. 2019. https://doi.org/10.1093/jxb/erz455

Menéndez AB, Calzadilla PI, Sansberro PA, Espasandin FD, Gazquez A, Bordenave CD, Maiale SJ, Rodríguez AA, Maguire VG, Campestre MP, Garriz A, Rossi FR, Romero FM, Solmi L, Salloum MS, Monteoliva MI, Debat JH, Ruiz OA. Polyamines and Legumes: Joint Stories of Stress, Nitrogen Fixation and Environment. Front Plant Sci 10: 1415. 2019. https://doi.org/10.3389/fpls.2019.01415

Nieva AS, Vilas JM, Gárriz A, Maiale SJ, Menéndez AB, Erban A, Kopka J, Ruiz OA. The fungal endophyte Fusarium solani provokes differential effects on the fitness of two Lotus species. Plant Physiol Biochem. 144: 100-109. 2019. https://doi.org/10.1016/j.plaphy.2019.09.022

Pires N, Maiale S, Venturino A, Lascano C. Differential effects of azinphos-methyl and chlorpyrifos on polyamine oxidative metabolism during the embryonic development of Rhinella arenarum and its relation to oxidative stress. Pestic Biochem Phys. En Prensa. 2019. https://doi.org/10.1016/j.pestbp.2019.10.007