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A two‐year experiment assessed herbage production and above‐ and below‐ground characteristics of a highly productive monoculture ('BRS Zuri' guineagrass [Panicum maximum Jacq.]) and two mixtures of three grasses (Mixture 1: 'BRS Zuri' guineagrass, 'BRS Xaraés' palisadegrass [Brachiaria brizantha Stapf.], and 'Basilisk' signalgrass [Brachiaria decumbens Stapf.]; Mixture 2: 'BRS Quênia' guineagrass [Panicum maximum Jacq.], 'Marandu' palisadegrass [Brachiaria brizantha Stapf.], and 'BRS Paiaguás' palisadegrass [Brachiaria brizantha Stapf.]), cultivated in the Brazilian tropical savanna. Mixtures 1 and 2 were subjected to two grazing intensities (removal of 40 or 60% of pre‐grazing height) and 'BRS Zuri' guineagrass monoculture was defoliated to a single grazing intensity of 50%. Treatments were randomly assigned to fifteen 0.25‐ha plots and managed under intermittent stocking by cattle. Herbage accumulation rate was similar among pastures and years (p >.1). The root mass in the tussocks did not differ (p >.1), with mean values ranging between 0.62 to 1.81 kg DM m−2. Root density in the tussock interspaces was greater in the mixtures (p <.001), regardless of seasons (p =.405) and years (p =.292). The mixtures were dominated by guineagrass (70%) and palisadegrass (30%) at the end of the experiment, with the population of 'Basilisk' and 'BRS Paiaguás' being completely suppressed throughout the experimental period. Mixing guineagrass and brachiariagrasses can be an alternative to the traditional pastoral systems in the tropics, as it does not compromise herbage production and presents a capacity to produce more roots than a very productive monoculture of 'BRS Zuri' guineagrass. [ABSTRACT FROM AUTHOR]

The aim of this work was to evaluate the effects of chitosan emulsion (CE) in combination with essential oils (Eos) on blue mold control, as well as on aroma and quality attributes of "Fuji" apples after storage. Treatments evaluated were control, CE (1%) and CE (1%) combined with citronella, clove and copaiba EOs (all EOs at 500 μl L−1). Fruits treated with EC and EC + OEs showed lower total phenolic compounds in the peel in all treatments. Fruits treated with EC combined with citronella OEs (242.4 OD mg–1 of protein min–1) and clove (205.8 OD mg–1 of protein min–1) showed lower peroxidase activity in fruit peel tissue. Therefore, CE and CE combined with citronella, clove and copaiba essential oils reduced the development of blue mold in "Fuji" apples. In addition, the treatments with lower severity of blue mold showed lower peroxidase activity in the peel and pulp tissues of the fruit, indicating induction of resistance by essential oils. Novelty impact statement: Chitosan biofilm reduces rot by P. expansum in "Fuji" apples, and when in addition to chitosan, essential oils of citronella, clove and copaiba are used, there was an increase in the reduction of disease severity.The aroma of the fruit did not present a characteristic aroma of the essential oils used with the method of application used.There were no changes in fruit quality attributes with the use of chitosan and chitosan biofilm with the addition of essential oils. [ABSTRACT FROM AUTHOR]

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The objective of this work was to evaluate the effect of nitric oxide (NO) application (dose and frequency) on ripening delay and oxidative stress reduction in Cavendish banana stored in a controlled atmosphere (CA). The treatments evaluated were 0 and 20 μl/L NO applied at the start of storage, 0.5 and 1 μl/L NO applied daily, and 1 and 5 μl/L NO applied every 5 days. The treatments of 1 μl/L applied daily and 5 μl/L applied every 5 days caused a reduction in ethylene production and respiration, delayed yellowing, had higher flesh firmness, and increased superoxide dismutase enzyme activity. The daily application of 1 μl/L NO also provided greater activity of the peroxidase enzyme and less lipid peroxidation, demonstrating less oxidative stress. The application of 1 μl/L NO daily in CA storage reduced oxidative stress in Cavendish banana. Practical applications: This study analyzed the effect of nitric oxide (NO) application (dose and frequency) during controlled atmosphere (CA) storage of Cavendish bananas as a way to preserve fruit quality. The use of NO in a CA delays the yellowing of the fruits, maintains the flesh firmness, delays the ripening, and reduces the oxidative stress in Cavendish bananas and can be used as a strategy to prolong storage and maintain fruit quality. [ABSTRACT FROM AUTHOR]

A less‐explored alternative to animal production in the subtropics is a mixture of perennial cool‐ and warm‐season forage grasses. This study aimed to determine a grazing management strategy to enhance forage production and attenuate the seasonality of a mixed pasture composed of kikuyugrass (Pennisetum clandestinum) and tall fescue (Festuca arundinacea). Four treatments were implemented in a completely randomized block design using a factorial scheme (2 × 2) with three replicates. The factorial arrangement consisted of two canopy heights (12 and 17 cm) associated with or without a single autumn grazing of 7 cm. Evaluations were conducted over 2 years. Nitrogen fertilization was performed only during the winter and spring seasons. Regardless of grazing height targets (12 or 17 cm), severe defoliation in autumn increased forage accumulation by 10% in mixed pastures composed of kikuyugrass and tall fescue; however, such management strategy should not be recommended because it delayed canopy recovery by 90–120 days, restrained winter grazing, and, paradoxically, increased forage production seasonality. Tall fescue was the dominant species in all treatments in the second year of evaluation, and we hypothesized that the lack of N fertilization during the summer impaired the persistence of kikuyugrass and was the main reason for this dominance effect. Therefore, we suggest evaluating summer N fertilization strategies, which could benefit both species and ensure the persistence of kikuyugrass in the mixture. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the defoliation patterns of individual tillers, efficiency of herbage utilisation, and forage production in continuously stocked Brachiaria humidicola cv. Comum swards during periods of the year of restricted pasture growth. The experiment was conducted at the Embrapa, Campo Grande-MS, Brazil, from April to October 2012. Treatments consisted of two grazing management strategies, defined by two ranges of sward height (10–15 and 20–25 cm) managed under continuous and variable stocking rates. The experiment was conducted as a completely randomised block design with three replications. During periods of resource constraints, grazing management strategies based on 'steady state' sward heights did not alter defoliation patterns, herbage utilisation efficiency (HUE), and forage production in Brachiaria humidicola swards under a continuous stocking method. A direct implication of our results is that grazing management strategies during the driest and coldest periods of the year in the tropics should be developed based on the conditions most suitable for better promoting faster pasture recovery and a return to production in the following spring; it is unlikely that any grazing management strategy would be successful in increasing herbage production and/or HUE in periods of restricted pasture growth. [ABSTRACT FROM AUTHOR]

The effects of different management strategies on improving growth and modifying the botanical composition of C3 and C4 perennial grasses grown in a mixed canopy are underexplored. We aimed to evaluate the botanical composition and vegetation dynamics of a mixed canopy containing kikuyugrass (Pennisetum clandestinum Hochst. Ex Chiov) and tall fescue (Festuca arundinacea Schreber cv. Rizomat) subjected to four grazing management strategies over 22 mo. The experimental design was a randomized complete block in a factorial arrangement (two maintenance canopy heights: grazed to 7 cm in the autumn, or uninterrupted and maintained at 12 or 17 cm) with three replicates. The plots were sampled every month throughout the experimental period; the forage mass data were used to determine the botanical composition and leaf area index of the canopy. Although autumn grazing to 7‐cm height promoted an increase in pasture leaf proportion, it did not represent an effective augment in pasture leaf mass in the following winter–spring season. Canopies heights managed at 17 cm presented a greater proportion of tall fescue in herbage mass (81%) compared with those maintained at 12 cm (73%). Severe defoliation in the autumn delayed the regrowth to 12‐ or 17‐cm canopy heights by approximately 90–120 d in both evaluation years. From a farm‐level perspective, this result would restrict the recommendation of this grazing management strategy because this time lapse would demand that the pastures not be grazed for the 25–33% period of the year compared with the pastures that were not grazed in the autumn. [ABSTRACT FROM AUTHOR]

The current work was based on the central hypothesis that grazing management strategies modulate tillering dynamics of mixed canopies composed of kikuyu-grass (C4 perennial grass) and tall fescue (C3 perennial grass). Among the five grazing management conditions evaluated, three (7, 12, and 17 cm) represented the heights up to which the grasses were kept by mimicking a continuous stocking method throughout the experimental period (from May 2016 to October 2017), and the other two consisted of the heights 12 and 17 cm with a single grazing to 7 cm in mid-autumn. Nitrogen fertilization was applied only during winter–spring. The results showed that under severe grazing (7 cm), kikuyu-grass predominated in the area and that tall fescue population predominated in the moderately lenient (12 cm) and lenient (17 cm) grazed pastures, regardless of an occasional autumn grazing to 7 cm. After two years of evaluation, kikuyu-grass tillers were reduced to 6% of the total population in those pastures managed at the heights of 12 and 17 cm. Grazing management strategies modulate species proportions in a mixed canopy composed of kikuyu and tall fescue. Moreover, our data also suggest that it seems unlikely that there is a stable association of tall fescue and kikuyu-grass when no nitrogen fertilization is applied during summer. [ABSTRACT FROM AUTHOR]