Fisisologia do florescimento e viabilidade do grão-de-pólen da cana-de-açúcar (Saccharum sp.)
Carregando...
Data
2012-02-16
Autores
Melloni, Maria Letícia Guindalini [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
Este trabalho teve por finalidade o estudo da fisiologia e a viabilidade do pólen para fins de melhoramento de cana-de-açúcar. Para isto três trabalhos foram realizados. No primeiro foi estimada a taxa de autofecundação de famílias obtidas por policruzamento envolvendo quatro genótipos (IACSP95-5000, IAC94-1099, RB867515, SP89-1115) além do impacto da taxa de autofecundação nas taxas de sobrevivência e seleção das progênies obtidas. O policruzamento foi realizado na cidade de Ribeirão Preto-SP. Após o teste de germinação das sementes obtidas, as que apresentaram viabilidade (sementes da IACSP95-5000 e SP89-1115) foram semeadas em campo onde permaneceram por 10 meses para avaliação da taxa de sobrevivência (4, 6 e 10 meses) e seleção (aos 10 meses). A taxa de autofecundação foi determinada por meio de marcadores microssatélites. Para as progênies da IACSP95-5000 e SP89-1115 as taxas de autofecundação foram de 98,5% e 0% respectivamente. A taxa da sobrevivência foi maior para as progênies da SP89-1115 nas duas últimas avaliações bem como a taxa de seleção no valor de 78,26% contra 28,18% das progênies da IACSP95-5000. O segundo trabalho teve como objetivo comparar dois corantes (iodo 0,1N e azul de lactofenol) utilizados para avaliar viabilidade do pólen de inflorescências de cana-de-açúcar com a germinação em meio de cultura. A leitura da viabilidade do pólen foi realizada em microscópio fotônico (250x) para cada corante, dentro de cada horário, para quatro genótipos de cana-de-açúcar na estação de hibridação do IAC em Uruçuca-Ba. O meio de cultura para germinação foi composto de água de chuva, sacarose (300g/L) e ágar-ágar (10g/L). O corante azul de lactofenol mostrou queda da viabilidade do pólen com o passar das horas de avaliação, o corante de iodo...
The present work aimed to investigate the flowering and the physiology of pollen viability for sugarcane breeding. For these purpose three studies were conduce. In the first one, the selfing rate of polycross derived families involving 4 parents (IACSP95-5000, IAC94-1099, RB867515, SP89-1115) was estimate as also as its impact on the survival and selection rate of the progenies. The polycross was done at Ribeirão Preto-SP. After the seed germination test, those that were viable (IACSP95-5000 and SP89-1115 seeds) were planted in the field where stayed for 10 months for the survival (4, 6 and 10 months) and selection rate (at 10 months) evaluation. The selfing rate was estimated through microsatellite markers. For the progenies derived from IACSP95-5000 and SP89-1115 the selfing rates were 98.5% and 0% respectively. The survival rate was higher for SP89-1115 derived progenies at the last two evaluations as well as the selection rate with 78.26% against 28.18% observed for IACSP95-5000 progenies. In the second study two dyes (iodine 0.1N and lactophenol blue) used to evaluate pollen viability from sugarcane tassels were compared with the pollen germination at culture media composed by rain water, sucrose (300g/l) and agar-agar. The read of pollen viability was done with a photonic microscope (250x) for each dye, in each time for 4 sugarcane genotypes at the IAC cross station (Uruçuca-BA). The lactophenol dye showed a degree of pollen viability with the evaluation time while the iodine dye did not. Compared with the germination in culture media at 6 hours, both dyes did not differ, but, over estimated the viability obtained through germination. At 8 and 9 hours, the iodine dye over estimate the pollen germination while the lactophenol blue under estimate. In the third study the behavior of 17 sugarcane... (Complete abstract click electronic access below)
The present work aimed to investigate the flowering and the physiology of pollen viability for sugarcane breeding. For these purpose three studies were conduce. In the first one, the selfing rate of polycross derived families involving 4 parents (IACSP95-5000, IAC94-1099, RB867515, SP89-1115) was estimate as also as its impact on the survival and selection rate of the progenies. The polycross was done at Ribeirão Preto-SP. After the seed germination test, those that were viable (IACSP95-5000 and SP89-1115 seeds) were planted in the field where stayed for 10 months for the survival (4, 6 and 10 months) and selection rate (at 10 months) evaluation. The selfing rate was estimated through microsatellite markers. For the progenies derived from IACSP95-5000 and SP89-1115 the selfing rates were 98.5% and 0% respectively. The survival rate was higher for SP89-1115 derived progenies at the last two evaluations as well as the selection rate with 78.26% against 28.18% observed for IACSP95-5000 progenies. In the second study two dyes (iodine 0.1N and lactophenol blue) used to evaluate pollen viability from sugarcane tassels were compared with the pollen germination at culture media composed by rain water, sucrose (300g/l) and agar-agar. The read of pollen viability was done with a photonic microscope (250x) for each dye, in each time for 4 sugarcane genotypes at the IAC cross station (Uruçuca-BA). The lactophenol dye showed a degree of pollen viability with the evaluation time while the iodine dye did not. Compared with the germination in culture media at 6 hours, both dyes did not differ, but, over estimated the viability obtained through germination. At 8 and 9 hours, the iodine dye over estimate the pollen germination while the lactophenol blue under estimate. In the third study the behavior of 17 sugarcane... (Complete abstract click electronic access below)
Descrição
Palavras-chave
Cana-de-açúcar, Marcadores biologicos, Hibridação vegetal, Sugarcane breeding
Como citar
MELLONI, Maria Letícia Guindalini. Fisisologia do florescimento e viabilidade do grão-de-pólen da cana-de-açúcar (Saccharum sp.). 2012. vii, 64 f. Dissertação (mestrado) - Universidade Estadual Paulista, Faculdade de Ciências Agrárias e Veterinárias, 2012.