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Plants of the genus Cynodon were considered as weed for a long period. However, this scenario has changed when it was observed that many species could be used in forage farming and for the recovery of degraded areas. Due to the hi...
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Plants of the genus Cynodon were considered as weed for a long period. However, this scenario has changed when it was observed that many species could be used in forage farming and for the recovery of degraded areas. Due to the high expansive potential, Cynodon spp. became an option for producers and aroused interest for breeding programs, besides requiring further studies on genetic and cytogenetic variability. Research onmeiosis in Cynodon are scarce since the inflorescences are small and the standardization of the stages of spikelet collections is difficult. The aim of the present study was to evaluate the microsporogenesis, viability and morphology of the pollen grains of two accessions of Cynodon dactylon var. dactylon (L.) Pers. (2n = 4x = 36, bermudagrass) and two accessions of Cynodon nlemfuensis var. nlemfuensis Vanderyst (2n = 2x = 18, stargrass). The slides were prepared by squash technique and stained with 2% carmine propionic. For the viability analyses of pollen grains, 2% propionic carmine and Alexander's stain were used. The measurements and the morphology of the pollen grains were defined from analyses with the acetolysis technique and scanning electron microscopy. The meiosis of the four accessions/species was regular. The staining tests showed variations in the viability rate of the pollen grain between the diploid and tetraploid species, being higher among the tetraploids. The pollen grains measured 21.1 and 28.8 mu m on average for both species and were classified as oblate spheroidal, monocolpates and showed no ornamentation, such as spicules and other attachments with non-roughened, micro reticulated exine. (c) 2018 SAAB. Published by Elsevier B.V. All rights reserved.
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Plant recovery due to herbicide symptoms of phytotoxicity characterizes an additional waste of energy that should not be accepted as a natural physiologic response; therefore, it might result in yield losses. Herbicide-tolerant fo...
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Plant recovery due to herbicide symptoms of phytotoxicity characterizes an additional waste of energy that should not be accepted as a natural physiologic response; therefore, it might result in yield losses. Herbicide-tolerant forages and the use of less phytotoxic products on pastures provide improvements in chemical weed control and increases in forage yield. The objectives of this study were to test differences between Tifton 85 (Cynodon spp.) and African star grass (Cynodon nlemfuensis) in relation to their degree of tolerance to herbicides, as well as the selectivity of herbicides for both species. The experimental design was completely randomized, in a 2 x 8 factorial, with four replicates. Two species of Cynodon and eight herbicide treatments were evaluated. The tolerance and selectivity of herbicides for Tifton 85 and African star grass are a function of each species and the type and dose of herbicide applied. Among the two species of Cynodon, Tifton 85, in general, was more tolerant to the applied herbicides than was the African star grass and consequently with less probability to occur forage yield losses. The most phytotoxic herbicides for both forages were fluroxypyr + aminopyralid (160.0 + 80.0 g ae/ha [grams of acid equivalent per hectare]), fluroxypyr + triclopyr (320.0 + 960.0 g ae/ha) and glyphosate (180 g ae/ha). The most selective herbicides were bentazon (720.0 g ai/ha [grams of active ingredient per hectare]), imazapyr (25.0 g ai/ha) and MSMA (1,440.0 g ai/ha), which have potential for use in fields of Tifton 85 and African star grass.
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Aqueous extracts of Lemon grass (Cymbopogon citratus) and Star-anise (Illicium verum) were prepared and evaluated for antioxidant activity using various in vitro assay systems. The extracts, even at low concentrations, worked as e...
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Aqueous extracts of Lemon grass (Cymbopogon citratus) and Star-anise (Illicium verum) were prepared and evaluated for antioxidant activity using various in vitro assay systems. The extracts, even at low concentrations, worked as efficient scavengers of DPPH (IC_(50) of 72-90 ug/ml), and superoxide radicals (77-87% scavenging). The antioxidant activity coefficient as determined by (3-carotene bleaching assay was high (600-800). Both the extracts exhibited high reducing power indicating good antioxidant potential. Lipid peroxidation, monitored as thiobarbituric acid-reactive substance (TBARS) were significantly lower (p<0.05) in irradiated meat containing these extracts. Antioxidant potential of Star anise extract was better than Lemon grass extract.The extracts were able to protect against radiation induced DNA damage in pBR322 plasmid.
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To improve the financial sustainability and business management of composting facilities, mostly small-scale and manually operated facilities, the simultaneous optimization of the process and quality of the final product must be p...
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To improve the financial sustainability and business management of composting facilities, mostly small-scale and manually operated facilities, the simultaneous optimization of the process and quality of the final product must be prioritized. This study used artificial neural networks (ANNs) and particle swarm optimization (PSO) as tools to evaluate the composting of biowaste (BW) with different cosubstrates (i. star grass (SG) and ii. a SG and sugarcane filter cake (SFC) mixture). The simulation aimed to maximize product quality in the shortest processing time by varying the mixing ratio and turning frequency. The simulation showed optimal conditions with a turning frequency of twice per week with the following mixtures: (i) BW:SG (72.9:27.1), 76 days of processing; and (ii) BW:SFC:SG (60:16:24), 88 days of processing. The results showed the effect of the type of carbon source in the cosubstrates on the retention time, which may imply the need for a larger area in composting facilities. On the other hand, the findings show that a minimum time is required to achieve a product that meets quality standards, although a longer processing time reduces the agricultural value of the compost. This model can be used to define design criteria and operating conditions and select a cosubstrate that can contribute to improving the agricultural quality of the final product.[GRAPHICS].
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Con el objetivo de caracterizar un sistema tradicional de producción pecuaria se desarrolló un estudio de diagnóstico estático en Colima, México. El trabajo valoró aspectos técnicos, sociales y económicos. Los resultados m...
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Con el objetivo de caracterizar un sistema tradicional de producción pecuaria se desarrolló un estudio de diagnóstico estático en Colima, México. El trabajo valoró aspectos técnicos, sociales y económicos. Los resultados mostraron un alto grado de similitud entre los productores agropecuarios, siendo la siembra asociada y el pastoreo continuo del pasto estrella (Cynodon plectostachyus P.) y el rastrojo de maíz (Zea mays L.) la base del sistema de producción, el cual se caracterizó por el uso racional y limitado de insumos, el autoconsumo, el autoempleo y la falta de asistencia técnica.
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ASIA-PACIFIC – Six plants native to Southeast Asia are promising cancer warriors.ASIA-PACIFIC – Possible link between autism and antidepressants use during pregnancy.ASIA-PACIFIC – Novel nanoparticle vaccine to fight against ME...
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ASIA-PACIFIC – Six plants native to Southeast Asia are promising cancer warriors.ASIA-PACIFIC – Possible link between autism and antidepressants use during pregnancy.ASIA-PACIFIC – Novel nanoparticle vaccine to fight against MERS-CoV.ASIA-PACIFIC – World’s first molecular swing.ASIA-PACIFIC – Cancer cells are addicted to methionine.ASIA-PACIFIC – New treatment for fatty liver disease.REST OF THE WORLD – New post-doctoral programme to accelerate dementia research.REST OF THE WORLD – A genomic test can help predict outcomes in men with prostate cancer.
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