Nitrogen influenced biomolecular changes on Physalis L. species studied using 2DCOS spectral analysis coupled with chemometric and Receiver operation characteristics analysis.

The determination of the molecular composition of plant leaves is essential to assist in nutritional management, whether for cultivated or non-cultivated species. In this sense, the study aimed to apply FTIR technique in combination with chemometrics and ROC analysis for the evaluation of changes in compositional of plant leaves of Physalis angulata and Physalis peruviana due to nitrogen fertilization treatments. Both species were grown under different doses of nitrogen (0, 200, 400, and 600 Kg ha-1) and leaf samples were evaluated using ATR-FTIR. Our results demonstrate that the spectra of both species were influenced by the nitrogen doses. The computed band area from the lipid/amide, lipid/carbohydrates, degree of esterification and calcium oxalate shows nitrogen fertilization due to 400 Kg ha-1 of N treatment is more effective for a better quality of yield. 2D correlation spectral analysis (2DCOS) reveals cellulose and pectin begins changes followed by amide of proteins due to nitrogen treatment in P. peruviana samples. The P. angulata plants shows hemicellulose changes predominating followed by proteins and polysaccharides. The obtained principle component analysis plot and loading values show the Physalis species samples distinctly separated from control with protein and carbohydrates are predominant in influencing separation among them. Receiver operation characteristic analysis shows a higher value of area under the curve reflecting better reliability of the experiments carried out. Hierarchical cluster analysis shows closed separation for a similar group on dissimilarity scale. Thus the use of 2DCOS coupled with chemometrics helps to identify changes in the composition of leaves of physalis species due to nitrogen doses, constituting a fast and precise measuring for the suitable management of this fertilization.

Morphological characterization of fruits, diaspores and germination of Miconia ligustroides (DC) Naundim (Melastomataceae) / Caracterização morfológica dos frutos, diásporos e germinação de Miconia ligustroides (DC) Naundim (Melastomataceae)

Miconia ligustroides (DC.) Naudim, popularly known as "vassoura-preta" or "jacatirão-do-brejo" is widely distributed in Brazil. It is a recommended species for restoration of riparian areas and its fruits are attractive to wildlife. However, little is known about the morphology of its fruits and diaspores. Such morphological characterization studies are important for species identification, corroborating future studies of phenology and germination. Therefore, the fruits, diaspores and germination of M. ligustroides were morphologically characterized by observations through naked eye, stereoscopic microscopy and scanning electron microscopy. Analyses of chemical composition of seeds were also performed. The fruits are spherical and uniform within the analyzed sample, having a large number of tiny obtriangular yellowish-brown diaspores. The diaspores are considered ananfitropos, and have crystals in their external envelope. Concerning chemical composition, they are proteins. Germination is of phanerocotylar type and starts at 12 Days After Sowing (DAS); at 17 DAS each diaspore may produce up to three seedlings. The morphological characterization performed in this work was efficient to describe the fruits, seeds and germination of this species, thus providing the basis for future studies.

Miconia ligustroides (DC.) Naudim, popularmente conhecida como vassoura-preta ou jacatirão-do-brejo, é amplamente distribuída no Brasil. É uma espécie recomendada para restauração de matas ciliares, e seus frutos são atrativos à fauna. No entanto, pouco se conhece acerca da morfologia de seus frutos e diásporos, e é sabido que estudos de caracterização morfológica são importantes para a identificação de espécies, além de corroborarem estudos futuros de fenologia e germinação. Portanto, os frutos, diásporos e geminação de M. ligustroides foram caracterizados morfologicamente por meio de observações visuais a olho nu, em microscópio estereoscópico e por meio de Microscopia Eletrônica de Varredura. Análises da composição química das sementes também foram realizadas. Os frutos são esféricos e uniformes dentro da amostra analisada. Possuem grande número de diminutos diásporos castanho-amarelados e obtriangulares. Os diásporos são considerados ananfítropos e possuem cristais em seu envoltório externo. Quanto à composição química, são proteicos. A germinação é do tipo fanerocotiledonar e inicia-se aos 12 Dias Após Semeadura (DAS), sendo que aos 17 DAS cada diásporo pode originar até três plântulas. A caracterização morfológica realizada neste trabalho foi eficiente em descrever os frutos, sementes e germinação desta espécie, de modo a subsidiar estudos futuros.