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Emmanouil Roditakis Christina Skarmoutsou Marianna Staurakaki María del Rosario Martínez‐Aguirre Lidia García‐Vidal Pablo Bielza Khalid Haddi Carmelo Rapisarda Jean‐Luc Rison Andrea Bassi Luis A Teixeira 《Pest management science》2013,69(2):217-227
BACKGROUND: Tuta absoluta(Meyrick) is one of the most serious pests of tomato recently introduced in the Mediterranean region. A novel bioassay method designed for the accurate determination of insecticide toxicity on T. absoluta (IRAC method No. 022) was validated by three different laboratories [Greece (NAGREF), Italy (UC) and Spain (UPCT)] on European populations. RESULTS: The insecticides indoxacarb and chlorantraniliprole were used as reference products. The IRAC leaf dip method is easy to perform, producing repeatable, homogeneous responses. LC50 values for indoxacarb ranged between 1.8 and 17.9 mg L?1 (NAGREF), 0.93 and 10.8 mg L?1 (UC) and 0.20 and 0.70 mg L?1 (UPCT), resulting in a tenfold, 12‐fold and fourfold difference between the least and most susceptible populations at each laboratory respectively. For chlorantraniliprole, LC50 values ranged between 0.10 and 0.56 mg L?1 (NAGREF), 0.23 and 1.34 mg L?1 (UC) and 0.04 and 0.24 mg L?1 (UPCT), resulting in a sixfold difference in all three cases. Overall, UPCT reported lower mean LC50 to indoxacarb, while UC reported higher LC50 to chlorantraniliprole. CONCLUSIONS: The new bioassay is reliable, providing a useful tool in the design of IRM strategies. Within each country/lab, the variability observed in the results for both indoxacarb and chlorantraniliprole can be attributed to natural variation. Future research is necessary to determine the extent to which it is possible to compare results among laboratories. Copyright © 2012 Society of Chemical Industry 相似文献
136.
Jos de Jesús Ornelas-Paz Elhadi M. Yahia Alfonso A. Gardea 《Postharvest Biology and Technology》2008,50(2-3):145-152
High-performance liquid chromatography–atmospheric pressure chemical ionization (APcI+)-time-of-flight mass spectrometry studies revealed that all-trans-β-carotene and the dibutyrates of all-trans-violaxanthin and 9-cis-violaxanthin were the main carotenoids in ‘Ataulfo’ and ‘Manila’ mango fruit mesocarp. The concentration of these carotenoids in the mesocarp was measured during fruit ripening and correlated with colorimetric changes of mesocarp and epidermis. The lowest and highest concentrations of all-trans-β-carotene, all-trans-violaxanthin and 9-cis-violaxanthin (as dibutyrates) during the ripening of ‘Manila’ mango were 0.25 × 10−3 to 35.57 × 10−3, 0.40 × 10−5 to 31.97 × 10−3 and 0 to 16.81 × 10−3 g kg−1 of fresh mesocarp, respectively. For ‘Ataulfo’ they were 2.55 × 10−3 to 39.72 × 10−3, 0.16 × 10−3 to 15.00 × 10−3 and 0.21 × 10−3 to 7.48 × 10−3 g kg−1 of fresh mesocarp, respectively. The concentration of these carotenoids increased in an exponential manner during fruit ripening in ‘Ataulfo’ and in an exponential or second-order polynomial manner in ‘Manila’. The highest correlation coefficients were obtained for the relationships between the mesocarp and epidermis a* and h° color values and the concentration of the evaluated carotenoids in both mango cultivars (R = 0.81–0.94). Equations to predict the concentration of the most important carotenoids in ‘Manila’ and ‘Ataulfo’ mango fruit on the basis of their mesocarp and epidermis color values were obtained. 相似文献
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Samia Yahiaoui Alfonso Cuesta‐Marcos Maria P. Gracia Blanca Medina José M. Lasa Ana M. Casas Francisco J. Ciudad José L. Montoya Marian Moralejo José L. Molina‐Cano Ernesto Igartua 《Plant Breeding》2014,133(2):218-226
Barley landraces from the western Mediterranean area have not been thoroughly exploited by modern breeding. This study aims at assessing the agronomic value of a core collection of lines derived from landraces of Spanish origin and to compare them with sets of successful old and modern cultivars. The agronomic performance of a set of 175 barley genotypes, comprising 159 landrace‐derived lines and 26 cultivars, was evaluated in a series of 10 field trials, carried out over 3 years and several locations. The most relevant trait of the landraces was higher grain yield at low production sites than cultivars, which may be related with better ability to fill the grain under stressful conditions. On the other hand, lateness, excessive plant height and lodging were negative traits frequently found in the landraces. Large genotype‐by‐environment interaction (GEI) for grain yield was detected, related partly with differences between germplasm groups, probably indicating local adaptation. GEI was also associated with the interaction of heading time and powdery mildew resistance with temperature. 相似文献
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Brenda Oaxaca-Villa Alejandro Casas Alfonso Valiente-Banuet 《Genetic Resources and Crop Evolution》2006,53(2):277-287
Reproductive biology of the columnar cactus Escontria chiotilla was analysed in wild and silvicultural managed populations in the Tehuacán Valley, Central Mexico, where this cactus is under
domestication because of its edible fruits. Anthesis is diurnal, flowers opening between 8:00 and 17:00 h, the period between
12:00 and 13:00 appearing to be crucial in pollination success since at this time the maximum opening of flowers, turgidity
of stigma, and activity of flower visitors, as well as the highest nectar production and pollen release occur. The bees Apis mellifera, Bombus pensylvanicus and Xylocopa mexicanorum, and the hummingbirds Amazilia violiceps, Cynanthus sordidus and Cynanthus latirostris were the most frequent flower visitors during the crucial period, and were observed contacting both stamens and stigma of
E. chiotilla. No differences were found in anthesis nor in flower visitors among both population types. Distances separating the populations
studied and bridges of individuals of E. chiotilla between them are within the radius that bees and hummingbirds may travel, indicating that spatial barrier to pollen flow
are unlikely. Breeding system is self-incompatible. Production of flowers occurs during the whole year in both population
types, allowing continual pollen flow among them. This observation confirms reports of high gene flow among the populations
studied in previous population genetics studies. The high pollen flow among wild and managed population explains that however
the occurrence of artificial selection, the process of domestication is in incipient stages presumably because gene flow counteracts
effects of artificial selection. 相似文献
140.
We studied the persistence of 281 towns of the black-tailed prairie dog (Cynomys ludovicianus) from surveys conducted in Oklahoma in 1966 and 1967 and again in 1988 and 1989. Town size during initial surveys tended to increase along a northwesterly gradient toward the panhandle of the State, and larger towns tended to occur in clusters while small towns occurred as isolates. Persistence of prairie dog towns from 1967 to 1989 increased significantly with town size and decreased with town isolation, with higher persistence for towns that occurred in landscapes with greater coverage of other towns. Comparisons to our studies of persistence of towns mapped in 1989 and resurveyed in 1997 [Journal of Mammalogy, 82 (2001) 937] indicate that the latter part of this pattern was reversed, with persistence highest for the most isolated towns. The reversal in persistence patterns may be attributed to an outbreak of plague (Yersinia pestis) during the early 1990s, favoring isolated towns. We recommend adaptive management and a mixed strategy for the development of prairie reserves which should include networks (clusters) of relatively large reserves, along with large but isolated reserves across the species’ native range. 相似文献