Physiological Maturity of Parapiptadenia rigida Seeds

Abstract

The establishment of appropriate standards related to the physiological and morphological aspects of the seeds are fundamental procedures to help the nurserymen and seed producers in determining the maturity and the appropriate moment of collection of the fruits. In this sense, the objective of this research is to evaluate the physiological maturation of seeds of Parapiptadenia rigida by means of germination and vigor tests, based on the color of the pods. The seeds were collected in June 2017, from three matrices located in the municipality of Marechal Cândido Rondon, Paraná, Brazil. The pods were classified in four stages of maturation, according to the Chart of colors model “Munsell colors chart” for plants tissues, and measured the biometric parameters. The parameters observed to evaluate the germinative potential are: first germination count, germination velocity index, emergency velocity index, and fresh and dry matter masses of seedlings. The experimental design was completely randomized, with five maturation stages and four replicates of 25 seeds each. The averages were compared using the Tukey test at a 5% probability. The germination test showed that the increase in physiological potential of P. rigida seeds is associated with the progresses of pod maturation. Therefore, the vigor test demonstrated that the physiological maturation of the species is simultaneous with the change of coloration and maturation of the pods.

Momento de colheita de sementes de <i>Albizia hasslerii</i> (Chod.) Burkart em função da cor do fruto

“…Essa característica pode ocorrer, pois conforme Marcos Filho (2015), as sementes de muitas espécies têm a capacidade de germinar poucos dias após a fecundação do óvulo, antes de alcançar a maturidade fisiológica. Marini et al (2012) e Braz et al (2018), trabalhando com maturação de sementes de Luehea grandiflora e Paraptadenia rigida respectivamente, também verificaram baixa porcentagem de germinação de sementes contidas em frutos verdes.…”

“…O estádio 1 (100% verde) foi o que apresentou menor IVG. Braz et al (2018), estudando maturação de fruto de Paraptadenia rigida, encontraram resultados semelhantes para o IVG, em que o estádio de maturação verde apresentou menores médias e com o decorrer da maturação as sementes apresentaram maior velocidade de germinação.…”

“…(SCHULZ et al, 2017); e Parapiptadenia rigida (Benth.) Brenan (BRAZ et al, 2018). Esses estudos relatados possibilitam considerar a cor dos frutos como um bom indicativo do momento de colheita, sendo esse atributo de cunho prático e seguro.…”