Resgate De Embriões Em Pessegueiro: Tempo De Incubação

Abstract

RESUMOO sucesso no desenvolvimento de plântulas, a partir de embriões imaturos tem sido obtido desde 1936. Entretanto, quanto menor é o embrião, mais complexo e difícil é alcançar a porcentagem desejável de sobrevivência. O objetivo do presente trabalho foi avaliar o período de tempo que as sementes de clones muito precoces deveriam ficar em meio de cultura e à temperatura de 22 ±1 °C, antes de serem submetidas à embriocultura. Também foi avaliado o efeito de se conservar as frutas em câmara fria, por uma semana, antes de ser feito o resgate de embriões. Os resultados indicam que o tempo para incubação dos mesmos, à temperatura de 22 ±1 °C pode ser de até seis semanas, mas o melhor é entre três e quatro semanas. O fator limitante é a contaminação das sementes por patógenos. Também é possível obter sucesso com a técnica de resgate de embriões de frutas conservadas por uma semana em câmara fria, desde que o tempo de incubação não seja superior a três ou quatro semanas.Palavras-chave: embriocultura; embriões imaturos; Prunus persica. ABSTRACTSuccess with immature embryos has been achieved since 1936. However, as smaller is the embryo more complex and difficult is to have a desirable survival percentage. The objective of this work was to check the period of time that seeds should be kept in the culture media at 22 ±1 °C, before being submitted to the embryo culture procedure. The effect of keeping the fruits for a week in cold room, previously to the ovule rescue, was also evaluated. Results showed that the time for ovule incubation at 22 ±1 °C, can be up to nine weeks but better three to five weeks. The limiting factor is related to seed contamination by pathogens. It is also possible to have success with ovule rescue of embryos of fruits kept for one week in cold room, as long as the time, the ovule incubation period, is not superior to three or four weeks.

Embryo Rescue of Cold-hardy Table Grapes

“…A 10-point categorical scale (A-J) was used to rate embryo development into normal seedlings and was modified from Ji et al (2013) to include categories for dead embryos and somatic embryogenesis in vitro. Plantlet development was analyzed based on work by Raseira and Einhardt (2010), a 5-point scale with descriptors: 1, dead embryo; 2, white or green but without leaves; 3, weak or dry tip; 4, minimal growth; and 5, normal vigorous growth. The number of days to germination was assessed when a seedling's cotyledons or hypocotyl were visible.…”

Germination and Development of 'Precocinho' Peach Embryos: Asepsis and Use of PPMTM in Culture Medium

“…Seeds from mother plants whose fruits have a short fruit development period may present germination problems because the embryo is immature at the time of harvest. However, embryo culture is a technique that makes possible the germination and development of immature embryos, being essential in a breeding program [2,3,4]. Without this technique, early ripening peach cultivars could not be used as parents, since the percentage of germination would be very low [5].…”