<b>Germination and development of <i>Amburana cearensis</i> seedlings as influenced by seed weight, light and temperature

Abstract

ABSTRACT. The objective of this work was to study the seed germination and seedling growth of A. cearensis (Allemão) A. C. Sm. influenced by seed weight and under different temperature and light conditions. Seeds were individually weighed and divided into three weight classes (light, medium and heavy), and each was subjected to germination tests under two light conditions (presence or absence) and six temperature regimes (20, 25, 30, 35, 40, and 20-30°C). The experiment was established with a completely randomized design in a split-split plot arrangement with four replicates. We determined the first count, final germination percentage and germination speed index. To assess seedling growth, the length and dry mass of the epicotyl and root + hypocotyl axis were also determined. The data were subjected to Tukey's test (p ≤ 0.05). The optimal conditions for seed germination occurred at a temperature of 30°C, with light and medium seeds showing greater vigour. Temperatures of 35 and 40°C were detrimental to the growth of the species, whereas the best conditions occurred with light and medium seeds at temperatures of 25 and 30°C in the presence of light.Keywords: cumaru, abiotic factors, seed vigour.Germinação e desenvolvimento de plântulas de Amburana cearensis em função do peso da semente, luz e temperatura RESUMO. O objetivo do trabalho foi estudar a germinação de sementes e o crescimento de plântulas de Amburana cearensis (Allemão) A. C. Sm. em função do peso das sementes sob diferentes condições de temperatura e luz. As sementes foram pesadas individualmente e separadas em três classes (leves, médias e pesadas), e cada uma foi submetida a testes de germinação em duas condições de luz (presença e ausência) e seis regimes de temperatura (20, 25, 30, 35, 40 e 20-30°C). O experimento foi inteiramente casualizado em parcela subsubdividida com quatro repetições. Nós determinamos a primeira contagem, porcentagem final e o índice de velocidade de germinação. Para a avaliação do crescimento das plântulas, o comprimento e a massa seca do epicótilo e do eixo raiz/hipocótilo. As condições ótimas para a germinação das sementes ocorreram na temperatura de 30°C e com um maior vigor com sementes leves e médias. As temperaturas de 35 e 40°C foram prejudiciais ao crescimento da espécie, enquanto as melhores condições ocorreram com as sementes leves e médias nas temperaturas de 25 e 30°C e na presença de luz.Palavras-chave: cumaru, fatores abióticos, vigor de sementes.

Germination ecology of cerejeira (Amburana acreana (Ducke) A. C. Sm.) seed as a function of temperature and photoperiod

“…It observed a positive response for cerejeira tree germination in the range of 25 to 35 ºC, this demonstrates that the seed germination process is favored by warmer environments and in relation to the photoperiod it obtained 100% germination for the period of 30 ºC / 24 h light. The optimal temperatures reported here are in agreement with other studies carried out with seeds of the same genus, such as the cumaru-de-scent (Amburana cearensis) (GUEDES et al, 2010;ALMEIDA et al, 2017), and also with species from the same family, sombreiro (Clitoria fairchildiana) (ALVES et al, 2011) and pay phone (Enterolobium contortisiliquum) (RAMOS, 2018). The optimal temperature for germination is a primordial factor that guarantees the action of seed reserves in the establishment of the species, being responsible for the increase in metabolism and for the translocation of these reserves to the embryonic axis (ALMEIDA et al, 2017).…”

Pattern of seedling emergence and early growth in Avicennia germinans and Rhizophora racemosa along an experimental salinity gradient

“…and Bruguiera gymnorrhiza (L.) Lam. In addition to the above external factors, intrinsic features of seeds (weight, length, diameter and origin) also affect the emergence patterns of many Asian and American mangrove species (Almeida et al, 2017;Das, 2001;Das & Ghose, 2003;Purnobasuki et al, 2016).…”

Immersion in 6-Benzylaminopurine for Dormancy Release and Initiation of Potato Sprouts at Various Tuber Weight and Storage Duration

“…The seeds that have larger size and weight have more food reserves than the small, and it is suspected that the buds size is also larger. Food reserves stored in seeds are carbohydrates, proteins, fats and minerals (Almeida et al, 2017). These materials are needed for the embryo as raw materials and energy during the germination process.…”