Recuperação e resposta germinativa de sementes de leguminosas passadas pelo trato digestório bovino

Abstract

NAKAO, E.A. & CARDOSO, V.J.M. Recovery and germination of legume seeds passed through the digestive tract of bovine cattle. Biota Neotrop. 10(3): http://www.biotaneotropica.org.br/v10n3/en/ abstract?article+bn03410032010.Abstract: Seed germination can be influenced by passage through the digestive system of animals, which can act as seed dispersers, depending on how seeds are affected. When passing through the animal digestive tract does not reduce the seeds germination, the dispersal agent is considered legitimate. The effects of ingestion by bovine cattle (Bos Taurus Linnaeus (1758)) on the viability and germination of seeds of the species Leucaena leucocephala (Lam.) de Wit, Cajanus cajan (L.) Huth and Calopogonium mucunoides Desv. was investigated in this study, aiming at evaluating the role of cattle as legitimate dispersers of those forage plants. Seed samples were mixed with the food offered to three B. taurus females, whose feces were collected 36 hours after ingestion, and seeds recovered from the feces were quantified and tested for germination and initial seedling growth. Noningested seeds were used as a control. The percentage of undamaged seeds recovered ranged from 12.3 to 17.5%. The germination capacity (germinability) of C. cajan was strongly inhibited by the cattle ingestion, whereas the germinability of C. mucunoides was less affected. The germinability of L. leucephala was not influenced by the ingestion probably due to their hard seed coat. The germination rate of C. mucunoides and L. leucocephala seeds was slightly increased by cattle ingestion, whereas the Emergence Rate Index (ERI) was reduced in the former. The ingestion by cattle also caused a decrease in the growth rate of C. cajan and C. mucunoides seedlings, although this inhibitory effect was smaller in C. cajan. Resumo: A germinação de sementes pode ser influenciada pela passagem através do trato digestório animal, que, nesse caso, poderá atuar como dispersor, dependendo de como as sementes são afetadas. Quando a passagem pelo trato digestório animal não reduz a capacidade germinativa das sementes, o agente dispersor é considerado legítimo. Este trabalho aborda a influência da ingestão de sementes de Leucaena leucocephala (Lam.) de Wit, Cajanus cajan (L.) Huth e Calopogonium mucunoides Desv. por Bos taurus Linnaeus (1758), sobre sua germinação e viabilidade, com o objetivo de avaliar o gado bovino como legítimo agente dispersor dessas espécies utilizadas como forrageiras. Amostras de sementes foram misturadas ao alimento oferecido a três fêmeas de B. taurus, cujas fezes foram recolhidas até 36 horas após a ingestão e submetidas à triagem para recuperação das sementes, as quais foram testadas para germinação e crescimento inicial. Como controle foram usadas sementes intactas não ingeridas. A porcentagem de recuperação de sementes não danificadas variou de 12,3% até cerca de 17,5%. A ingestão pelos animais afetou severamente a capacidade de germinação das sementes de Cajanus cajan, enquanto que em Calopogonium mucunoides a redução da ...

Germination, Vigor of Seeds and Emergence of Fabaceae Seedling in Bovine Faeces

“…The leucaena seeds expelled between 18 and 54 hours after the ingestion were the ones that originated bigger seedlings, both for the aerial part and for the root (Figure 2(b) and Figure 2(c)). These results are similar to those found by [16], which observed that the leucaena seeds that went through bovine GIT originated higher seedlings than the intact seeds. For the Cajanus cajan seeds, the passage through bovine GIT reduced the growth rate for the height of the seedlings.…”

“…In an emergency essay on Fabaceae seedlings in bovine faeces, [16] observed an emergence of zero for dwarf pigeon peas. For broad fava beans and calopo, the root protrusion was observed, but not the development of the seedlings.…”

“…These authors believe that the residence time of the seeds in the faeces has a direct relation with their mortality, in addition to the total dehydration of the faecal plate in two days [17]. Nevertheless, in open field conditions, the stomping, the rain, and, mainly the activity of coprophage beetles may modify the substrate and create a microenvironment that is favorable to the germination of seeds and to the growth of the seedlings deposited in the faeces, in such a way that they do not act as a limiting factor for dispersion [16].…”

“…The percentage of emerging seedlings in the faeces was low, ranging between 2.5% and 8.63% for the total amount of ingested seeds. In contrast, [16] tendered 9000 seeds of each one of the legumes to cattle: Leucaena leucocephala (Lam.) of Wit, Cajanus cajan (L.) Huth, and Calopogonium mucunoides; it also recovered 12% of the Cajanus cajan seeds and 17.5% of the Calopogonium mucunoides seeds.…”

Recovery and seeds germination of four important tropical forage legumes in bovine dung

“…Furthermore, they found that in vitro incubation revealed to be more harmful to the seeds of the three species used. Nakao and Cardoso (2010) studied the influence of the ingestion of Leucaena leucocephalaseeds, Cajanus cajan and Calopogonium mucunoides by Bos taurus, on germination and viability, in order to evaluate the cattle as legitimate disperser of these species used as fodder. These authors found that eating the animals severely affected the germination of seeds of Cajanus cajan, while in Calopogonium mucunoides reduction of germination percentage was occurred on a smaller scale and the Leucaena germination was not affected by treatment.…”