Water absorption and physiological responses of hog plum tree diaspores to storage

Abstract

<jats:p>Abstract Hog plum tree seeds (Spondias mombin L.) have a complex dormancy mechanism, which causes slow germination and great unevenness. At present, there are no efficient methods to promote seed germination. The objective of the study was to evaluate the effect of storage on overcoming seed dormancy of this Anacardiaceae. Diaspores of two hog plum trees were used, identified as Mother plant 1 and Mother plant 2, established in Tomé-Açu city, PA. Initially, it was investigated whether the structures surrounding the seeds (internal mesocarp and endocarp) prevent water absorption. For this, the diaspores of the two mother plants were sown between blotting paper, with an adequate level of water and, periodically, in the total of 144 hours, the water content of the seeds was computed. The storage studies involved two experiments. In the first, diaspores from both mother plants with a water content of around 5.0% were stored in impermeable packages, for one year, under the following conditions: natural environment of Belém, PA (average temperature of 26.8 °C) and at temperatures of 6 ± 1 ° C and minus 18 ± 2 °. The germinative response of the stored diaspores was compared with those of non-stored diaspores. Prior to storage, selection was made on the diaspores, discarding the small ones. In the second experiment, the germinative response of the diaspores of the two mother plants, stored for zero, one, two, three, four, five and six months, under natural environment conditions of Belém, PA, was evaluated. It was observed that the structures that cover the seeds do not offer restrictions to the water absorption, thus discarding the hypothesis of physical dormancy, without, however, excluding the possibility of mechanical dormancy. The storage of diaspores for one year, regardless of the storage condition, did not affect the germination power of the seeds. On the other hand, responses of great magnitude, in terms of reducing the time required for germination, were obtained when the diaspores were stored under natural conditions and at minus 18±2 °C, indicating that dormancy is naturally overcome by storage . Overcoming dormancy was a little slower when the diaspores were stored at a temperature of 6±1 °C. It was found that the storage of diaspores in an environment with an average temperature of 26.8 °C for three months provides the overcoming dormancy of most of the seeds. The intensity of dormancy varied within and between mother plants.</jats:p>

Problems Concerning Dormancy and Its Investigation in Hog Plum (Spondias Mombin Linn.): A Review

“…There, it is possible to note that when Heat and Cold stratification work isolate to break dormancy there is evidence of Non-Deep Simple level. As we have seen before, Silva (2003) and Carvalho and Nascimento (2020) has found exactly that, make the point of this level of dormancy. Furthermore, for Spondias tuberosa, Arr.…”

“…Morphological dormancy is characterized by the small size of the embryo, avoiding the germination at that time, but not cut down the capacity of germination at all, because if it is given time enough, the process can be concluded normally (FINCH-SAVAGE and LEUBNER-METZGER, 2006). Carvalho and Nascimento (2020), realize that storage in environmental temperature, Hog plum diaspores gets faster and even over the germination, indicating that time was the only factor needed to break dormancy and point toward a morphological dormancy. Besides, it was found that heat stratification during seven days (time to allow the embryo mature) at 30o C, after imbibition and heating in an oven, has a significative effect in the Index of Velocity of Emergence (IVE) compared with the control treatment, however, in the Percentage of Germination, this distinction was not found (SILVA, 2003).…”

“…Morphophysiological or physiological dormancy may be the predominant cause of the low germination in Hog plum. Research findings indicated that, if seeds Yellow mombin has time enough under environmental temperature, its germinations get faster and more even (CARVALHO and NASCIMENTO, 2020), namely, dormancy is naturally overruled, and morphological dormancy probably is present in this fruit once it occurs when the embryo is underdeveloped, and only time can overcome it. It is important to pinpoint, nonetheless, that some studies point out that scarification (both mechanical and chemical) can enhance the germination percentage (FADIMU et al, 2014;OYEBAMIJI et al, 2014;MARTIN et al, 2019), what can only be explained by non-deep physiological dormancy once this method (scarification) is suitable to break this level of dormancy (BASKIN and BASKIN, 2008).…”

Byrsonima crassifolia L. Kunth a bio-resource with potential: Overview and opportunities

“…When seed propagation includes an agronomic management system, it generates fruits with more homogeneous characteristics than those obtained from wild or backyard crops (Agredano-de la Garza et al, 2021). Germination (sexual reproduction) increases with pretreatments such as soaking with water, gibberellic acid, solutions, and sulphuric acid (Carvalho and Do Nascimento, 2013;Guzmán et al, 2013;Dos Reis Barbosa et al, 2020). After germination, seedlings can grow in different substrates, allowing the selection of low-cost and accessible substrates in the propagation area.…”

Efeito do ácido giberélico na germinação de sementes e na produção de biomassa inicial em Virola surinamensis (rol.) warb. (Myristicaceae)

“…O experimento foi conduzido em ambiente natural de laboratório sem controle de temperatura e umidade relativa do ar (mínima e máxima temperatura e umidade relativa do ar foram 22ºC e 29ºC, e 74% e 95%, respectivamente), com irrigações a cada dois dias ao longo do período de avaliação. Trabalhos em condições semelhantes foram realizadas com outras espécies arbóreas amazônicas (David, et al, 2020;Carvalho & Nascimento, 2020;Barros, et al, 2019;Pereira, et al, 2016).…”