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Previous issue date: 2001-12-18 / Annnonaceae family approximately 128 genus and 2300 species. (Judd, 1999), being the Annona muricata L.. andAnnona squamosa L. the most important species of this genus (Pinto e Silva, 1995). Salinity can affect some processes in the plant life cycle. Plant responses to salt exposure are complex and involve alterations in morphology, physiology, anatomy and primary and secondary metabolism. Therefore, salt stress effects can be studied by analyzing aspects related to anatomical, metabolic and growth alterations. The main objective of this work was to analyze the anatomical (through the light microscopy and scanning electron microscopy), metabolic (amino acid composition), growth and development alterations (roots length, shoots length, fresh weight, dry weight and leave surface) in A. muricata L. and A. squamosa L. seedling esposed to salinity (NaCl) in the Unidade Experimental Horto Florestal, Universidade Estadual de Feira de Santana. The experiments were performed in a 12:12 h light/dark cycle at 26? C/ 20? Cin a hydroponic system and the salt trataments were carrid out five different concentrations of NaCl (0, 3, 100, 300 and 500 mM ) for periods of 1, 2 and 3 days for 2 weeks old seedlings. Similar experiment was carrid ourt two months old seedlings which were exposed to 0, 100 and300 mM NaCl for periods 1, 2, 3 and 7 days. The growth of A. squamosa seedlings was more affected by NaCl than A, muricata seedlings. Root length and leaf area for both species were inhibited by the hightest NaCl concentrations test. However, for A. muricata the fresh weight and shoots length remained at the levels of the control plants. Te analyses of fresh and dry wight suggested that the reduction in growth observed was due to water uptake reduction, but not a decrease in the rate of photosynthesis. The Annona muricata L. exhibited a better control of stomata opening under salt stress. Anatomic alterations such as chloroplast size (increased volume) were cleary observed under NaCl treatment in both species whereas the leaves of A. muricata exiibited an increased number of trichomes, including in control plants which suggest to salinity. The presence of Cl - in the different tissues of both the species showed that this ion was almost equally distribuited within the plant system since it was not observed any accumulation in the roots. It was also present in the leaves. The amino acid analysis allowed to demonstrated the presence of prolina in leaves of both the species when exposed to the highest concentrations oh NaCl indicating the salt stress has been established in the seedlings. / A fam?lia Annnonaceae compreende aproximadamente 128 g?neros e 2300 esp?cies. (Judd, 1999), sendo a Annona muricata L. e a Annona squamosa L. as esp?cies mais importantes entre as ?rvores frut?feras. (Pinto e Silva, 1995). A salinidade afeta v?rios processos ao longo do ciclo de vida da planta. A resposta da planta ao excesso de sal ? complexa e envolve altera??es na sua morfologia, fisiologia, anatomia e metabolismos prim?rio e secund?rio. Portanto, os efeitos do estresse salino podem ser verificados nas altera??es anat?micas, metab?licas e no crescimento. O objetivo deste trabalho foi analisar as altera??es anat?micas (atrav?s da microscopia ?ptica e Eletr?nica de Varredura), metab?licas (composi??o de amino?cidos), de crescimento ( radicular, parte a?rea, peso fresco, peso seco e ?rea foliar) e desenvolvimento de pl?ntulas de Annona muricata L. e Annona squamosa L. submetidas a estresse salino. Os tratamentos salinos foram conduzidos em hidroponia na the Unidade Experimental Horto Florestal, Universidade Estadual de Feira de Santana sob temperatura controlada de 20? C (escuro )/26?C (luz) e fotoper?odo de 12 horas nas concentra??es de 0, 3, 100 300 e 500 mM de NaCl por 1 per?odos de 1, 2 e 3 dias para as pl?ntulas com 2 semanas de idade e de forma similar para pl?ntulas com 2 meses de idade por per?odos de 1, 2, 3 e 7 dias em 0, 100, 300 mM de NaCl. Os resultados mostraram que as pl?ntulas de pinha tem seu desenvolvimento mais afetado pelo NaCl do que as pl?ntulas de graviola. Em ambas as esp?cies as maiores concentra??es de NaCl inibiram o crescimento da raiz e da ?rea foliar. Por?m, graviola manteve o peso fresco e o comprimento da parte a?rea em rela??o ao controle. As an?lises de peso fresco e seco demonstraram que a diminui??o do crescimento ? devido a redu??o da absor??o de ?gua e n?o a queda na taxa fotossint?tica. A Annona muricata L. apresenta um melhor controle da abertura estom?tica em condi??es de estresse salino. Dentre as altera??es anat?micas, foi constatado que na presen?a de NaCl ocorre um aumento no volume dos cloroplastos de ambas as esp?cies e a maior presen?a de tricomas em Annona muricata L. inclusive no controle,poderia ser uma das caracter?sticas respons?veis pela melhor adapta??o desta esp?cie ? salinidade. A presen?a de Cl- nos diferentes tecidos vegetais de ambas as esp?cies mostrou que este ?on se distribui quase que igualmente pela planta, n?o tendo sido observado seu ac?mulo nas ra?zes. O Na+ foi acumulado nas ra?zes de graviola apesar de ter sido encontrado tamb?m nas folhas desta esp?cie. A an?lise de amino?cidos demonstrou a presen?a de prolina somente nas folhas de ambas as esp?cies nas concentra??es mais elevadas de Nacl , indicativo do estabelecimento do estresse nestas pl?ntulas.
| Identifer | oai:union.ndltd.org:IBICT/oai:tede2.uefs.br:8080:tede/56 |
| Date | 18 December 2001 |
| Creators | Passos, Vania Machado |
| Contributors | Pierre, Vit?ria, Angela |
| Publisher | UNIVERSIDADE ESTADUAL DE FEIRA DE SANTANA, Programa de P?s-Gradua??o em Bot?nica, UEFS, BR, Bot?nica |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Biblioteca Digital de Teses e Dissertações da UEFS, instname:Universidade Estadual de Feira de Santana, instacron:UEFS |
| Rights | info:eu-repo/semantics/openAccess |
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