Characterization and gas exchange in accessions of Saccharum complex under salinity in the Sub-middle São Francisco, Brazil

Abstract

Salinity is one of the factors that most limit agricultural yield in the Brazilian semi-arid region. In this context, the present study aimed to evaluate the leaf gas exchange and biometric characteristics of accessions of the Saccharum complex subjected to salt stress. The experiment was carried out in a greenhouse, installed at Embrapa Semiárido, in Petrolina, PE, Brazil. The experimental design was in randomized blocks, with the treatments represented by 19 accessions belonging to different genera/species, being 10 accessions of Saccharum officinarum (BGCN 6, BGCN 91, BGCN 104, BGCN 127, BCGN 90, BGCN 101, BGCN 102, BGCN 118, BGCN 125 and BGCN 122), two accessions of Saccharum spp. (BGCN 87 and BGCN 89), one accession of Saccharum hybridum (BGCN 88), one accession of Saccharum robustum (BGCN 94), four accessions of Erianthus arundinaceus (BGCN 117, BGCN 119, BGCN 120 and BGCN 123) and one accession of Miscanthus spp., with three repetitions. Biometric characteristics, chlorophyll index and leaf gas exchange of the accessions were evaluated when they were subjected to irrigation with salinized water (6.0 dS m-1). E. arundinaceus accessions (BGCN 120 and BGCN 123) showed the highest photosynthetic rate, transpiration rate, plant height and leaf length, indicating greater adaptability to salt stress and could be promising in breeding programs.

Saline stress affects the growth of Saccharum complex genotypes

“…Research on the Saccharum complex is being improved, mainly because the complex has genes related to resistance to biotic and abiotic stresses. Simões, Oliveira, Tardin, et al (2021), by analysing the physiological performance of Saccharum complex genotypes grown in environments with and without saline stress, verified a differential response of the genotypes under salinity conditions. Simões, Oliveira, Silva, et al (2021) also found larger leaf length in E .…”

“…Simões, Oliveira, Tardin, et al (2021), by analysing the physiological performance of Saccharum complex genotypes grown in environments with and without saline stress, verified a differential response of the genotypes under salinity conditions. Simões, Oliveira, Silva, et al (2021) also found larger leaf length in E . arundinaceus accessions under saline stress.…”

Parâmetros bioquímicos, fisiológicos e produtividade de sorgo granífero irrigado com água salina

“…Sabe-se que cerca de 95% da água que as plantas absorvem é utilizada na regulação da temperatura, por meio da transpiração (Taiz et al, 2017), logo, com a redução da gs, há uma diminuição da taxa de transpiração e, como consequência, um aumento da Tf. Tais resultados corroboram diversos estudos encontrados na literatura (Simões et al, 2021;Guimarães et al, 2020;Soares et al, 2013). Reduções nas trocas gasosas com o aumento da CEes pode ser utilizado para sinalizar variedades com baixa tolerância à salinidade, haja vista que uma menor eficiência fotossintética pode se refletir na redução do crescimento e da produtividade das plantas, quando não há a presença de mecanismos compensatórios para manter o pleno funcionamento do metabolismo fotossintético (Lacerda et al, 2006).…”

“…As diminuições nas trocas gasosas de vegetais submetidos a ambientes salinos estão diretamente relacionadas ao efeito osmótico sobre o metabolismo da planta (Silva et al, 2013). Outros pesquisadores avaliando acessos do complexo Saccharum sob salinidade no Submédio São Francisco concluíram que a irrigação constante com água salina acima do limiar da cultura, diminui a taxa fotossintética líquida em consequência da redução da condutividade estomática (Simões et al, 2021).…”

Impacts of saline stress on the physiology of Saccharum complex genotypes

“…Considering that this complex is composed of the genera Erianthus , Sclerostachya , Miscanthuse and Narenga , these are phylogenetically close to Saccharum and capable of being used in gene introgression programmes (Oliveira et al, 2017; Todd et al, 2014). Simões et al (2021) found that some accessions of E . arundinaceus have higher photosynthetic rate and transpiration rate, these being adaptability characteristics of these accessions to salt stress.…”