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Aims: To evaluate the capacity of Lactobacillus hilgardii and Lactobacillus buchneri on modifying the bacterial community and improving fermentation and aerobic stability of high‐moisture corn (HMC). Methods and Results: High‐moisture corn was untreated (CTR), treated with L. hilgardii (LH) or L. buchneri (LB) at 600 000 CFU per gram fresh weight, or with L. hilgardii and L. buchneri at 300 000 CFU per gram fresh weight each (LHLB), and stored for 10, 30 or 92 days. Compared to CTR, inoculated silages had higher Lactobacillaceae relative abundance, lower yeasts numbers and higher aerobic stability. Treatment with LHLB resulted in a higher acetic acid concentration than LH and higher 1,2 propanediol concentration than LB, such differences were numerically greater at 10 and 30 days but statistically greater at 92 days. At 10 days, all inoculated silages were more stable than CTR, but LHLB was even more stable than LB or LH. Conclusions: The combination of L. hilgardii and L. buchneri had a synergistic effect on yeast inhibition, leading to greater improvements in aerobic stability as early as 10 days after ensiling. Significance and Impact of the Study: Lactobacillus hilgardii, especially in combination with L. buchneri, can improve the aerobic stability of HMC after a very short period of ensiling. [ABSTRACT FROM AUTHOR]

Byline: G.H.F. Santos, E.B. Silva, K.X.F.R. Sena, B.L. Silva, C.S.A. Lima This study investigates the influence of gamma radiation on the total phenols, tannins and antimicrobial activity of ethanolic plant extracts of the bark and leaves of Anadenanthera colubrina (Vell.) Brenan (angico). The extracts were separated into four groups (0, 5, 7.5 and 10 kGy) to quantify total phenols (Folin-Ciocalteu method), tannins (precipitation of casein), and antimicrobial activity (disk diffusion of Gram-positive, Gram-negative, acid-alcohol-resistant bacteria and yeasts; Minimal Inhibitory Concentration (MIC) of Gram positive and alcohol-acid resistant bacteria). Tannin levels were 52% to 57% of total phenols in bark, and 58% to 60% in leaves, and there was no statistically significant difference between groups. There was antimicrobial activity against Gram-positive and alcohol-acid-resistant bacteria (bark and leaves) and Gram-negative bacteria and yeasts (leaves). However, the gamma radiation had no influence on the levels of total phenols and tannins or the antimicrobial activity of extracts of bark and leaves of A. colubrina.

Knowledge on the reproductive biology of target insect pest is essential for the effective implementation of pheromone-based pest management tactics. In mealybugs, the second largest family of scale insects, the existence of female multiple mating was recently suggested. In this study, we aimed at testing how general is this behavior in mealybugs, by investigating polygyny and polyandry in two cosmopolitan pest mealybugs, Planococcus citri and Pseudococcus calceolariae. Males of these species were able to mate an average of 11.9 and 13.3 females, respectively, during their lifespan. The number of fertilized females per male decreased with male age/mating history for both mealybugs. We found no differences in female fecundity and fertility, when fertilized by males with different mating history. When we used male age as a proxy of mating history, we observed a significant negative effect on female fecundity. The females of both species remained receptive after first copula and eventually mated multiple times. The percentage of remated females of P. citri decreased linearly with time since first copula, with some maintaining receptivity up to 24 h. Males showed no preference between virgin and mated females, in static-air olfactometer tests. We found no benefit of female multiple mating in relation to fecundity. In biparental mealybugs, the mating system of males is possibly scramble competition polygyny; and that of females is possibly polyandry, with female receptivity restricted to a relatively short period. We discuss the practical implications of the results for pest management. [ABSTRACT FROM AUTHOR]