Genetic divergence for adaptability and stability in sugarcane: Proposal for a more accurate evaluation.

The best agro-industrial performance presented by a crop genotype in one environment may not be reproduced in another owing to complex edaphoclimatic variations. Therefore, breeding programs are constantly attempting to obtain, through artificial hybridization, novel genotypes with high adaptability and stability potential. The objective of this study was to analyze genetic divergence in sugarcane based on the genotypic values of adaptability and stability. A total of 11 sugarcane genotypes were analyzed for eight agro-industrial traits. The genotypic values of the traits were determined using mixed model methodology, and the genetic divergence based on phenotypic and genotypic values was measured using the Mahalanobis distance. The distance matrices were correlated using the Mantel test, and the genotypes were grouped using the Tocher method. Genetic divergence is more accurate when based on genotypic values free of genotype-environment interactions and will differ from genetic divergence based on phenotypic data, changing the genotype allocations in the groups. The above methodology can be applied to assess genetic divergence to obtain novel sugarcane genotypes with higher productivity that are adapted to intensive agricultural systems using diverse technologies. This methodology can also be tested in other crops to increase accuracy in selecting the parents to be crossed.

Evaluation of quality and gene expression of goat embryos produced in vivo and in vitro after cryopreservation.

In the present study, we aimed to identify morphological and molecular changes of in vivo and in vitro-produced goat embryos submitted to cryopreservation. In vivo embryos were recovered by transcervical technique from superovulated goats, whereas in vitro produced embryos were produced from ovaries collected at a slaughterhouse. Embryos were frozen by two-steps slow freezing method, which is defined as freezing to -32 °C followed by transfer to liquid nitrogen. Morphological evaluation of embryos was carried out by assessing blastocoel re-expansion rate and the total number of blastomeres. The expression profile of candidate genes related to thermal and oxidative stress, apoptosis, epigenetic, and implantation control was measured using RT-qPCR based SYBR Green system. In silico analyses were performed to identify conserved genes in goat species and protein-protein interaction networks were created. In vivo-produced embryos showed greater blastocoel re-expansion and more blastomere cells (P < 0.05). The expression level of CTP2 and HSP90 genes from in vitro cryopreserved embryos was higher than their in vivo counterparts. Unlikely, no significant difference was observed in the transcription level of SOD gene between groups. The high similarity of CPT2 and HSP90 proteins to their orthologs among mammals indicates that they share conserved functions. In summary, cryopreservation negatively affects the morphology and viability of goat embryos produced in vitro and changes the CPT2 and HSP90 gene expression likely in response to the in vitro production process.