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81.
Nimet Sema Gencer Nabi Alper Kumral H. Ozkan Sivritepe Melis Seidi Hilal Susurluk Bulent Senturk 《Phytoparasitica》2009,37(3):217-224
The spider mites Tetranychus urticae Koch and Panonychus ulmi (Koch) (Tetranychidae) cause severe economic losses to vegetable farms and deciduous fruit orchards in Turkey. One of their
predators, the ladybird beetle Stethorus gilvifrons (Muls.) (Col., Coccinellidae), aggregates on mite-infested patches of plants. The present study assessed whether there is
a role for herbivore-induced plant volatiles (HIPVs) and/or odors emitted directly from these two mite species in the aggregative
response of ladybird beetles. The olfactory responses of the predator females to volatiles from T. urticae- and/or P. ulmi-infested sweet pepper (four cultivars, viz. ‘Demre’, ‘Yalova Carliston’, ‘Kandil Dolma’ and ‘Yag Biberi’), kidney bean (cv.
‘Barbunya’) and apple (M9 rootstock) were investigated using a two-choice olfactometer. Our results showed that HIPVs emitted
from both T. urticae- and P. ulmi-infested plants significantly attracted S. gilvifrons adults for all plants except the sweet pepper cv. Yag Biberi. In addition, it was found that volatiles from apple plants
infested by T. urticae and, especially, P. ulmi are more attractive for S. gilvifrons females than those emitted by other infested plants. The results also suggest that the odors of T. urticae adults and their products might influence the attraction of S. gilvifrons females. 相似文献
82.
Redesigning IT systems for specific user groups encompasses a lot of effort with respect to analysing and understanding user behaviour. The goal of this paper is to provide insights into patterns of behaviour of agricultural users, during the usage of a decision support system called OPTIRas™. This system aids agricultural users in their cultivar selection activities. We analyse logs resulting from OPTIRas™, and we get insights into user’s navigational patterns. We claim that the results of our analysis can be used to support the redesign of decision support systems in order to address specific agricultural users’ characteristics. 相似文献
83.
Ingestive behaviour of steers grazing Brachiaria brizantha cultivar Marandu and in feedlot in Brazil
de Souza Sinvaldo Oliveira Silva Robério Rodrigues da Silva Fabiano Ferreira de Carvalho Gleidson Giordano Pinto da Silva Ana Paula Gomes da Silva João Wilian Dias Santos Laize Vieira 《Tropical animal health and production》2019,51(8):2161-2166
Tropical Animal Health and Production - The objective of this study was to evaluate the ingestive behaviour of steers grazing Brachiaria brizantha cv. Marandu and in feedlot regimen in Brazil.... 相似文献
84.
Costa Evely Giovanna Leite da Silva Fabiano Ferreira Silva Robério Rodrigues Porto Antonio Ferraz Santiago Bismarck Moreira Rocha Leone Campos Cruz Aline Gonçalves Guedes Anna Caroline Ferreira Neto Teotônio Martins Vieira Edvaldo Alves 《Tropical animal health and production》2019,51(8):2505-2511
Tropical Animal Health and Production - The objective of this study was to evaluate the inclusion of increasing levels of licuri meal as a substitute for soybean bran in the diet of pasture-based... 相似文献
85.
86.
Isolated trees may significantly enhance biodiversity at the landscape level. However, our understanding of their impacts
is still poor, particularly in environments with high soil moisture where research on this topic has been comparatively limited.
We examined understorey vegetation and soil oribatid mite assemblages under live and dead Scots pine trees and in open treeless
areas, all within the same Scottish upland wet heath system, to determine whether isolated live trees affected the understorey
and mite components of the ecosystem, and whether these effects occurred in parallel. We also explored whether these responses
might result from tree-driven reductions in soil moisture content. Live trees reduced soil moisture (relative to wet heath
and beneath dead trees) and appeared to change vegetation from wet heath to dry heath type communities. These effects were
strongly related to tree trunk diameter (tree size). No major effects of dead trees on understorey vegetation or soil moisture
were apparent. Higher mite species abundance and richness were found under live trees than in treeless open heath. Although
mite abundances were lower under dead trees than live trees, richness remained similar, thus different factors seem to be
regulating mite abundance and community composition. These findings indicate that landscape-level biodiversity responses to
environmental change such as habitat fragmentation cannot be predicted from vegetation patterns alone, and that even in heavily
fragmented landscapes comparatively small patches such as isolated individual trees can enhance biodiversity. 相似文献
87.
Daniele Soares Barroso Neves Robério Rodrigues Silva Fabiano Ferreira da Silva Laize Vieira Santos George Abreu Filho Sinvaldo Oliveira de Souza Marceliana da C. Santos Weder Jansen Rocha Ana Paula Gomes da Silva Mateus de Melo Lisboa Maria Magna Silva Pereira Venício Macedo Carvalho 《Tropical animal health and production》2018,50(7):1411-1416
The aim of this study was to evaluate the effect of increasing concentrate supplementation levels on the intake, nutrient digestibility, and performance of crossbred steers during the dry period of the year. The experiment was developed on Princesa do Mateiro farm, in the municipality of Ribeirão do Largo, located in the southwest region of Bahia State, Brazil. Forty uncastrated male crossbred (½ Holstein-Zebu) steers with an average body weight (BW) of 232.55?±?24.97 kg were distributed into four treatments in a completely randomized design with ten replicates. The animals were managed in an experimental area formed by Brachiaria brizantha cv. Marandu, in an intermittent grazing system. Treatments consisted of the following supplementation levels: 0.2% BW, with 60% crude protein (CP); 0.3% BW, with 40% CP; 0.4% BW, with 30% CP; and 0.5% BW, with 24% CP. The intakes of forage dry matter in kg/day and %BW and neutral detergent fiber corrected for ash and protein (NDFap) in %BW decreased linearly, whereas the intake of non-fibrous carbohydrates corrected for ash and protein in kg/day and average daily gain increased linearly. Therefore, the use of supplementation at 0.5% BW (24% crude protein) to provide gains of up to 0.500 kg/day is recommended for grazing steers during the post-weaning period in the dry season of the year. 相似文献
88.
89.
90.
Cristina Santín Stefan H. Doerr Richard A. Shakesby Rob Bryant Gary J. Sheridan Patrick N. J. Lane Hugh G. Smith Tina L. Bell 《European Journal of Forest Research》2012,131(4):1245-1253
Forest fires release substantial amounts of carbon (C). Much of it is emitted to the atmosphere, but some is deposited within ash on the ground. Little is known about amount and types of C deposited in ash. Here, we quantify total C, and total inorganic, water-soluble and particulate organic fractions deposited in ash during the catastrophic 2009 ‘Black Saturday’ wildfires in Australia. These fires coincided with the highest air temperatures and lowest humidity ever recorded in the local area, which, combined with high fuel loads of mostly long unburnt eucalypt forests, generated extreme burning conditions. In three mixed-species eucalypt forest sites sampled, the canopy, understorey and litter fuels were almost completely consumed, resulting in substantial ash deposition (mean, 81.9 t ha?1), with 5.9 t ha?1 of C being transferred from vegetation to the forest floor. In five temperate rainforest sites sampled, the canopy was not burnt and ash deposition was lower (mean, 48.3 t ha?1) than in the mixed-species eucalypt forest, but overall their higher C content resulted in higher C deposition (8.1 t ha?1). In all cases, most C contained in ash was organic and its pyrogenic nature infers increased resistance to degradation. Pyrogenic C is viewed by many as an important C sink, which could contribute to long-term C sequestration when incorporated into soils or sediments. Our results highlight the potential importance of the pyrogenic C pool in freshly deposited ash and, therefore, the necessity of a systematic and detailed analysis of ash deposition and C forms in ash to improve our understanding of C fluxes by forest fires. 相似文献