Caracterização química de acesso do complexo Saccharum para resistência a pragas da ordem lepdoptera

Abstract

Brazil is the world's largest producer of sugarcane and for the 2020/2021 harvest this crop should reach a production of 665.105 million tons. An important restrictive factor for the expression of the potential of this crop in Brazil is the attack of pests and diseases, the most important pest being the sugarcane borer (Diatraea saccharalis). The objective of the present work was to chemically characterize accessions of the saccharum complex from the EMBRAPA germplasm bank, to perform antibiosis and antixenosis bioassays in accessions comparing them with the accession SP79 1011, susceptible to Diatraea saccharalis, adopted as susceptibility standard, to identify the VOCs possibly responsible for the differences observed in the antixenosis bioassay. Check metabolic differences in the leaves of the accessions between the plants of the control treatment and between the plants of the infested treatment. To verify metabolic differences of the SP79 1011 access stalk between the control and the infested treatments. The VOCs were analyzed using CG/MS and submitted to multivariate analyses. Soluble metabolites from leaves and stem were analyzed using NMR and submitted to multivariate statistical analysis. Twelve VOCs belonging to the classes of terpenes, hydrocarbons, alcohols, ketones and aldehydes were identified. The antixenosis bioassay showed that the IJ76 361 accession was less preferred by D. saccharalis when compared to SP79 1011. The IJ76 414 accession was more preferred by D. saccharalis when compared to SP79 1011. Leaf metabolomics enabled the identification of different metabolites soluble. Comparison of IJ76 361 and SP79 1011 revealed that metabolites such as gallic acid and chlorogenic acid were discriminating for these two accessions. From the metabolomics of the SP79 1011 accession stalk of the control and infested treatments, different metabolites such as alanine and aceto were identified that were discriminating for the analyzed plants. Thus, we suggest that the IJ76 361 accession can be used by breeding programs to obtain new varieties resistant to D. saccharalis.