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1.
Francisco A Macías Nuria Chinchilla Elena Arroyo Rosa M Varela José MG Molinillo David Marín 《Pest management science》2010,66(10):1137-1147
BACKGROUND: Fifteen novel derivatives of D‐DIBOA, including aromatic ring modifications and the addition of side chains in positions C‐2 and N‐4, had previously been synthesised and their phytotoxicity on standard target species (STS) evaluated. This strategy combined steric, electronic, solubility and lipophilicity requirements to achieve the maximum phytotoxic activity. An evaluation of the bioactivity of these compounds on the systems Oryza sativa–Echinochloa crus‐galli and Triticum aestivum–Avena fatua is reported here. RESULTS: All compounds showed inhibition profiles on the two species Echinochloa crus‐galli (L.) Beauv. and Avena fatua L. The most marked effects were caused by 6F‐4Pr‐D‐DIBOA, 6F‐4Val‐D‐DIBOA, 6Cl‐4Pr‐D‐DIBOA and 6Cl‐4Val‐D‐DIBOA. The IC50 values for the systems Echinochloa crus‐galli–Oryza sativa and Avena fatua–Triticum aestivum for all compounds were compared. The compound that showed the greatest selectivity for the system Echinochloa crus‐galli–Oryza sativa was 8Cl‐4Pr‐D‐DIBOA, which was 15 times more selective than the commercial herbicide propanil (Cotanil‐35). With regard to the system Avena fatua–Triticum aestivum, the compounds that showed the highest selectivities were 8Cl‐4Val‐D‐DIBOA and 6F‐4Pr‐D‐DIBOA. The results obtained for 6F‐4Pr‐D‐DIBOA are of great interest because of the high phytotoxicity to Avena fatua (IC50 = 6 µM , r2 = 0.9616). CONCLUSION: The in vitro phytotoxicity profiles and selectivities shown by the compounds described here make them candidates for higher‐level studies. 8Cl‐4Pr‐D‐DIBOA for the system Echinochloa crus‐galli‐Oryza sativa and 6F‐4Pr‐D‐DIBOA for Avena fatua‐Triticum aestivum were the most interesting compounds. Copyright © 2010 Society of Chemical Industry 相似文献
2.
Ana M. Casas Carlota R. Gazulla Arantxa Monteagudo Carlos P. Cantalapiedra Marian Moralejo M. Pilar Gracia Francisco J. Ciudad William T.B. Thomas José L. Molina-Cano Scott Boden Bruno Contreras-Moreira Ernesto Igartua 《作物学报(英文版)》2021,(4):862-872
Response to vernalization and photoperiod are the main determinants controlling the time to flowering in temperate cereals. While the individual genes that dete... 相似文献
3.
Guillermo Carrillo-Castañeda Juana Juárez Muñoz José R. Peralta-Videa Eduardo Gomez Jorge L. Gardea-Torresdey 《Journal of plant nutrition》2013,36(10):1853-1865
Microbes have developed high-affinity uptake mechanisms to assimilate iron (Fe) and other metals such as aluminum (Al), gallium (Ga), chromium (Cr), and copper (Cu). Siderophores, which are metal chelating compounds, and membrane receptor proteins are involved in these specialized mechanisms. A few siderophore-producing microorganisms associated with plant roots also influence the uptake of some metals. In this study, the potential microbial-assisted Cu and Fe uptake by Phaseolus vulgaris (common bean) plants was evaluated. Seedlings of cultivated common bean varieties Bayo-INIFAP (B) and Negro-150 (N) and wild types yellowish (WY) and black (WB) were developed in the presence of a Cu and Fe solution and associated with the siderophore-producing microorganisms R. leguminosarumbv. Phaseoli (strains 19, 44, and 46); Pseudomonas fluorescens(strain Avm), and Azospirillum brasilense (strain 154). Seedlings of cultivated variety N and black wild type WB inoculated with the strain CPMex.44 accumulated 71% and 30% more Fe than the un-inoculated plants, respectively; however, the wild black bean accumulated the highest absolute amount of Fe (221.56 mg/kg of dry matter) as compared with the cultivated black variety N (126.16 mg/kg of dry matter) (P < 0.05). In the wild type WY seedlings, the highest Fe accumulation was observed when the seeds were inoculated with the Pseudomonas strain Avm (206 mg/kg of dry matter) (P < 0.05). The interaction of Pseudomonas strain Avm with seedlings of the cultivated B variety and the wild type WB promoted the highest accumulation of Cu (51 and 54 mg/kg of dry matter, respectively), 7 and 14 mg more than in the respective non-inoculated seedlings. No promotion of Fe accumulation was observed in the seedlings of the cultivated B variety and in roots; instead, less Fe was accumulated. The wild type WY did not show any improvement in Cu accumulation. In this study, Rhizobiumstrains promoted Fe but not Cu uptake in P. vulgaris seedlings while Pseudomonas strains promoted the uptake of both Cu and Fe. 相似文献
4.
Macedo ML Damico DC Freire Md Toyama MH Marangoni S Novello JC 《Journal of agricultural and food chemistry》2003,51(10):2980-2986
This study describes the purification of an N-acetylglucosamine-binding lectin from Koelreuteria paniculata seeds and its effects on the larval development of Callobruchus maculatus and Anagasta kuehniella. The lectin (KpLec) was characterized and isolated by gel filtration, affinity column, and reverse phase chromatography. SDS-PAGE indicated that this lectin is a dimer composed of subunits of 22 and 44 kDa. The N terminus exhibited 40% similarity with Urtiga dioica agglutinin. KpLec was tested for anti-insect activity against C. maculatus and A. kuehniella. With regard to C. maculatus, an artificial diet containing 0.7 and 1% KpLec produced LD(50) and ED(50) value, respectively. However, for A. kuenhiella, an artificial diet containing 0.65% KpLec produced an LD(50), whereas 0.2% KpLec produced an ED(50). The transformation of genes coding for this lectin could be useful in the development of insect resistance in important agricultural crops. 相似文献
5.
Salas JH González MM Noa M Pérez NA Díaz G Gutiérrez R Zazueta H Osuna I 《Journal of agricultural and food chemistry》2003,51(15):4468-4471
A study was conducted to measure residues of 13 organophosphorus (OP) pesticides, widely used as dairy cattle ectoparasiticides or in crops used for animal feed, in homogenized and pasteurized Mexican milk samples. Four different milk brands with high distribution were collected biweekly during a 12 month period (n = 96) in supermarkets. OP pesticide residues were measured by gas chromatography with a flame photometric detector. Approximately 39.6% of the samples contained detectable levels of OP pesticide residues. Eight samples contained residues exceeding established maximum residue limits (MRL), and the OP pesticides present in these samples were dichlorvos (five samples), phorate, chlorpyrifos, and chlorfenvinphos (one sample, respectively). Average residues of 13 OP pesticides measured were below established MRLs ranging between 0.0051 and 0.0203 ppm. 相似文献
6.
Pérez-Magariño S González-San José ML 《Journal of agricultural and food chemistry》2004,52(5):1181-1189
Several red wines were elaborated to assess the effect of the degree of grape ripening on wine color and on the levels of flavanol and anthocyanin compounds, which are chiefly responsible for the wine color attributes. Two different cultivars and three different degrees of ripening were studied in two consecutive years. The wines were aged for 1 year in American oak barrels of medium-high char followed by 6 months in the bottle. The results showed that the wines made from more mature grapes had generally higher free anthocyanin content, and during aging the decrease of the free anthocyanins and flavanols took place in conjunction with an increase in the levels of the anthocyanin derivatives or "new pigments", which are responsible for maintaining color intensity and adding violet hues in aged wines. From the results obtained, it seems to be clear that the characteristics and composition of grapes harvested later (7-8 days in this region and for these varieties) than the usual time are quite beneficial to obtaining quality aged wines. The phenolic composition of wines made from the last harvested grapes is mainly responsible for the stability of their color, which is extremely important in product acceptance with a significant increase hence of product quality. 相似文献
7.
Ana de Santiago Alejandra Expósito José M. Quintero Eusebio Carmona Antonio Delgado 《Journal of plant nutrition》2013,36(2):143-156
Humic substances improve the efficiency of different iron (Fe) sources overcoming Fe deficiency chlorosis of plants. However, applied at high rates, they can promote negative effects on plants. The main objective of this work was to study the potential adverse effect of three humic acids from different origin when they were applied with two effective Fe sources for plants: Fe- ethylenediaminedihydroxyphenylacetic acid (EDDHA) and Vivianite. To this end, an experiment with lupin (Lupinus albus L.) was performed involving two factors: (i) Fe source, and (ii) humic substances from three different origin (composted cork, leonardite, and compost obtained from a mixture of olive husk with cotton gin trash) applied at 0, 0.1, and 0.5 g organic carbon (C) kg?1 of growing media. At the rates used, humic substances promoted adverse effects on plant development, chlorophyll meter readings, and Fe content in lupin grown in calcareous media. Overall, the effect on dry matter and Fe content in plants was more relevant when Fe was supplied with Vivianite, the effect on chlorophyll meter readings being more significant when Fe was applied as Fe-EDDHA. Differences were also observed depending on the source of humic substances, those from leonardite promoting the greatest decrease in dry matter in roots and shoots. These humic substances possessed the highest values of spectroscopy index for aromaticity (A254 ). On the other hand, the application of humic substances from olive husk compost, which exhibited the lower aromaticity index, resulted in the smallest decrease in dry matter production and chlorophyll meter readings. Dry matter in roots decreased logarithmically with increased values of the estimates of the amounts of aromatic compounds accumulated in the growing media (R2 = 0.92; P < 0.01) with Vivianite as Fe source. Thus, the effects decreasing dry matter production, particularly in roots, and chlorophyll meter readings can be ascribed at least partially to the presence of phytotoxic aromatic compounds in humic substances. 相似文献
8.
Simulated nitrogen deposition affects soil fauna from a semiarid Mediterranean ecosystem in central Spain 总被引:1,自引:0,他引:1
Raúl Ochoa-Hueso Iluminada Rocha Carly J. Stevens Esteban Manrique María José Luciañez 《Biology and Fertility of Soils》2014,50(1):191-196
Nitrogen (N) deposition is a major threat to the semiarid Mediterranean ecosystems. We simulated a gradient of N deposition (0, 10, 20 and 50 kg N ha?1 year?1?+?6.4 kg N ha?1 year?1 ambient deposition) in a Mediterranean shrubland from central Spain. In autumn 2011 (after 4 years of experimental duration), soil cores were taken to extract the soil fauna. Acari (45.54%) and Collembola (44.00%) were the most represented taxonomical groups, and their abundance was negatively related to soil pH. Simulated N deposition had an impact on the total number of individuals in soil as well as on Collembola and Pauropoda abundance. Collembola abundance increased with N loads up to 20 kg N ha-1 year-1 and then decreased. This response was attributed to soil acidification (between 0 and 20 kg N ha-1 year-1) and increased soil ammonium (between 20 and 50 kg N ha-1 year-1). Pauropoda were favoured by additions of 50 kg N ha-1 year-1, and it was the only taxonomical group whose abundance was exclusively related to N deposition, suggesting their potential as bioindicators. Contrary to predictions, there was a negative relationship between soil faunal abundance and plant diversity. In conclusion, soil faunal communities from semiarid Mediterranean ecosystems in central Spain seem to be primarily influenced by soil chemistry (mainly pH) but are also susceptible to increased N deposition. The main drivers of change under increased N deposition scenarios seem to be soil acidification and increased ammonium in soils where nitrate is the dominant mineral N form. 相似文献
9.
Carolina Reigada Rafael de Andrade Moral Clarice Garcia Borges Demétrio José Roberto Postali Parra 《Journal of pest science》2018,91(1):121-131
The cotton bollworm Helicoverpa armigera is a destructive pest that affects a variety of crop plants. Because of its polyphagous feeding habit, mobility as adults, and high fecundity, the expanding infestations of H. armigera in different crops have caused economic losses and difficulties for pest population management. In Brazil, a sequence of different crop systems in the same area and crop rotation during the year can create a spatio-temporal mosaic of crops where H. armigera can persist. However, the consequences of the simultaneous and/or alternating presence of host plants for H. armigera populations through generations are unknown. In this study, we simulated, in the laboratory, hypothetical situations for the availability of soybean and cotton crops in the landscape. We evaluated the effects of: (1) the number of generations during which a population feeds on a host-plant species; (2) the succession of host-plant species on which populations have fed for two generations; and (3) the parental host plant on the fitness of H. armigera populations. Only the current host plant on which larvae fed affected the performance of the H. armigera populations. Decrease of mortality rates during the immature period was slowed when the larvae fed on soybean. The lowest value of reproductive potential (R 0) was found for individuals originating from mating between females and males reared in cotton. Our results indicated that pest-management and biological-control plans for H. armigera should be developed on a regional scale rather than for just a specific crop area. 相似文献
10.
María Fuentes-Rubio José J. Cerón Carlos de Torre Damián Escribano Ana M. Gutiérrez Fernando Tecles 《Canadian journal of veterinary research》2014,78(2):127-132
The purpose of this research was to study changes in the salivary proteome of healthy pigs in stressful situations to identify any potential new salivary biomarker of stress. Three groups of animals were subjected to 3 stress models: snaring restraint followed by simulated sampling of vena cava blood; brief transport by road; and restriction of movement in a digestibility cage. Saliva was obtained from each animal before and 15 and 30 min after the induction of stress. The samples from the animals that showed the greatest increase in salivary cortisol concentration were pooled and run on 2-dimensional gels. Coomassie Brilliant Blue R-250 was used for spot detection and mass spectrometry for spot identification. Statistical analyses showed that 2 proteins had significant differences in expression before and after the induction of stress. These proteins were identified as odorant-binding protein and fragments of albumin. Further studies will be necessary to confirm the value of using these proteins as salivary biomarkers of stress in pigs. 相似文献