RESUMO: Os herbicidas, como uma parte importante da estratégia de controle de plantas daninhas em arrozais, têm diferentes impactos no crescimento e atividade de bactérias benéficas para o solo, como as espécies de Azospirillum. Um experimento de campo foi realizado no Sefid Rood Livestock and Agricultural Company, norte do Irã, para investigar a possibilidade de capina química em campos de arroz inoculados com Azospirillum lipoferum. O experimento foi desenvolvido em esquema fatorial, com base em blocos casualizados com três repetições. Os fatores foram a aplicação de Azospirillum (inoculação com ou sem Azospirillum lipoferum) e o regime de manejo de plantas daninhas (butaclor - aplicação com capina manual suplementar; bensulfuron-methyl - aplicação com capina manual suplementar; combinação de butaclor e bensulfuron-methyl - aplicação com capina manual suplementar, capina manual aos 15, 30 e 45 dias após o transplante e sem capina [não eliminados durante o período de cultivo de arroz). Os resultados mostraram que plantas inoculadas com A. lipoferum apresentaram rendimento de grãos 19% superior em comparação com aquelas que não foram inoculadas. As maiores produções de grãos foram registradas para parcelas tratadas com butaclor com capina manual suplementar (4.512 kg ha-1) e para aquelas tratadas com uma combinação de butaclor e bensulfuron-methyl com capina manual suplementar (4.500,5 kg ha-1). O menor rendimento (3.494,3 kg ha-1) foi registrado nos lotes que não foram capinados. Não houve interação significativa entre a aplicação de A. lipoferum e o regime de manejo de plantas daninhas para produção de grãos, indicando que os herbicidas não tiveram nenhum efeito adverso sobre a eficiência de A. lipoferum na promoção do crescimento e produtividade de grãos de arroz. Não houve diferença significativa nos pesos secos de plantas daninhas entre parcelas inoculadas e não inoculadas. O peso seco de plantas daninhas em parcelas capinadas manualmente e tratadas com herbicidas foi significativamente menor do que o do lote que não foi capinado. Em conclusão, o resultado desta experiência confirma a possibilidade de capina química em campos de arroz inoculados com A. lipoferum.

ABSTRACT: Herbicides, as a major part of weed control strategy in paddy fields, have different impact on growth and activity of soil-beneficial bacteria such as Azospirillum species. A field experiment was conducted at Sefid Rood Livestock and Agricultural Company, northern Iran, to investigate the possibility of chemical weed control in paddy fields inoculated with Azospirillum lipoferum. The experiment was designed in a factorial arrangement based on a randomized complete block with three replicates. The factors were Azospirillum application (inoculation with or without Azospirillum lipoferum) and weed management regime (butachlor application with supplementary hand-weeding, bensulfuron methyl application with supplementary hand-weeding, combination of butachlor and bensulfuron methyl application with supplementary hand-weeding, hand-weeding at 15, 30, and 45 days after transplanting, and no weeding [not weeded during the rice-growing period). The results showed that plants inoculated with A. lipoferum produced 19% higher grain yield compared to plants that were not inoculated. The highest grain yields were recorded for plots treated with butachlor with supplementary hand-weeding (4,512 kg ha-1) and for those treated with a combination of butachlor and bensulfuron methyl with supplementary hand-weeding (4500.5 kg ha-1). The lowest yield (3494.3 kg ha-1) was recorded for weedy plots. No significant interaction was detected between A. lipoferum application and weed management regime for grain yield, indicating that the herbicides had no adverse effect on the efficiency of A. lipoferum in promoting growth and grain yield of rice. There was no significant difference in the dry weights of weed between inoculated and non-inoculated plots. The dry weights of weed in hand-weeded and herbicide-treated plots were significantly lower than that of the weedy plot. In conclusion, the result of this experiment confirms the possibility of chemical weed control in paddy fields inoculated with A. lipoferum.

Resumo: O objetivo deste trabalho foi avaliar os efeitos da aplicação integrada de fertilizante nitrogenado e biofertilizantes sobre o rendimento, o período de enchimento de grãos e a composição de ácidos graxos de cártamo (Carthamus tinctorius). Os experimentos foram conduzidos em parcelas subdividas, durante as safras 2011 e 2012. Os tratamentos consistiram da inoculação de rizobactérias promotoras do crescimento de plantas (Azotobacter chroococcum estirpe 5, Azospirillum lipoferum estirpe F e Pseudomonas putida estirpe 186) nas sementes, nas subparcelas, com um controle sem inoculação; e da aplicação de diferentes níveis de adubação nitrogenada (60, 120 e 180 kg ha-1 de ureia) nas parcelas principais, com um controle sem aplicação de N. O maior rendimento de grãos, o maior período de enchimento de grãos e o período efetivo de enchimento de grãos foram obtidos com a aplicação de 180 kg ha-1 de ureia e com a inoculação de P. putida nas sementes. A aplicação de altas doses de N e a inoculação com P. putida resultaram no aumento de 25,66% da taxa potencial de enchimento de grãos. A inoculação de biofertilizantes nas sementes reduziu o teor de ácidos graxos saturados (ácidos palmítico e esteárico) e incrementou os ácidos graxos insaturados (ácidos linoleico, linolênico e oleico). A aplicação da quantidade adequada de adubação nitrogenada (120 a 180 kg ha-1 de ureia) pode melhorar o crescimento de plantas e a quantidade e a qualidade do óleo das sementes tratadas com P. putida, em plantas de cártamo.

Abstract: The objective of this work was to evaluate the effects of the integrated application of nitrogen fertilizer and biofertilizers on the yield, grain filling period, and composition of fatty acids of safflower (Carthamus tinctorius). Split-plot experiments were carried out during the 2011 and 2012 crop seasons. The treatments consisted of seed inoculation with plant growth-promoting rhizobacteria (Azotobacter chroococcum strain 5, Azospirillum lipoferum strain F, and Pseudomonas putida strain 186) in the subplots, including a control without seed inoculation; and of the application of N fertilizer at different rates (60, 120, and 180 kg ha-1 urea) in the main plots, including a control without N. The highest grain yield, grain filling period, and effective grain filling period were obtained by the application of 180 kg ha-1 urea and by seed inoculation with P. putida. The application of high N rates and P. putida inoculation resulted in 25.66% increase of the potential rate of grain filling. Biofertilizer inoculation in seed reduced the contents of saturated fatty acids (palmetic and stearic acids) and increased the contents of unsaturated fatty acids (linoleic, linolenic, and oleic acids). The suitable amount of N fertilizer (between 120 and 180 kg ha-1 urea) can improve plant growth, and the quantity and quality of oil in seeds treated with P. putida in safflower plants.

In Iran, both Plasmodium vivax and P. falciparum malaria have been detected, but P. vivax is the predominant species. Point mutations in dihydrofolate reductase (dhfr) gene in both Plasmodia are the major mechanisms of pyrimethamine resistance. From April 2007 to June 2009, a total of 134 blood samples in two endemic areas of southern Iran were collected from patients infected with P. vivax and P. falciparum. The isolates were analyzed for P. vivax dihydrofolate reductase (pvdhfr) and P. falciparum dihydrofolate reductase (pfdhfr) point mutations using various PCR-based methods. The majority of the isolates (72.9%) had wild type amino acids at five codons of pvdhfr. Amongst mutant isolates, the most common pvdhfr alleles were double mutant in 58 and 117 amino acids (58R-117N). Triple mutation in 57, 58, and 117 amino acids (57L/58R/117N) was identified for the first time in the pvdhfr gene of Iranian P. vivax isolates. All the P. falciparumsamples analyzed (n = 16) possessed a double mutant pfdhfrallele (59R/108N) and retained a wild-type mutation at position 51. This may be attributed to the fact that the falciparum malaria patients were treated using sulfadoxine-pyrimethamine (SP) in Iran. The presence of mutant haplotypes in P. vivax is worrying, but has not yet reached an alarming threshold regarding drugs such as SP. The results of this study reinforce the importance of performing a molecular surveillance by means of a continuous chemoresistance assessment.

The aim of this study was to evaluate the relative competitive ability of barnyardgrass (BYG, Echinochloa crus-galli (L.) P. Beauv.) compared to rice barnyardgrass (ECPH, E. oryzicola (Vasinger) Vasinger) against rice (Oryza sativa L.) cv. Hashemi in a replacement series study. Experiment was arranged in randomized complete block design with three replicates using a factorial treatment arrangement. Factors were two species of Echinochloa genus (BYG and ECPH) and five rice:BYG or rice:ECPH mixture proportions (8:0, 6:2, 4:4, 2:6, and 0:8). Relative yield total of aboveground dry weight, root dry weight and leaf area indicated that BYG or ECPH were competing for the same resources with ’Hashemi’. In general, replacement series curves and relative crowding coefficient (RCC) values demonstrated that both BYG and ECPH were more competitive than ’Hashemi’. BYG had significantly higher aboveground dry weight, root dry weight, tiller number, leaf area, and plant height than ECPH, when grown with ’Hashemi’. This experiment confirmed that BYG was more competitive than ECPH against ’Hashemi’.

El objetivo de este estudio fue evaluar la capacidad competitiva relativa de Echinochloa crus-galli (L.) P. Beauv. (BYG) en comparación con Echinochloa oryzicola (Vasinger) Vasinger (ECPH) contra arroz (Oryza sativa L.) cv. Hashemi en un estudio de series de reemplazo. Los experimentos fueron arreglados en diseno de bloques completos al azar con tres repeticiones con un arreglo factorial. Los factores fueron dos especies del género Echinochloa (BYG y ECPH) y cinco mezclas de arroz:BYG o arroz:ECPH (8:0, 6:2, 4:4, 2:6 y 0:8). El rendimiento relativo total del peso seco sobre el suelo, peso seco de raíces y área foliar indicaron que BYG y ECPH estaban compitiendo por los mismos recursos con ’Hashemi’. En general, las curvas de serie de sustitución y el coeficiente relativo de competencia (RCC) demostraron que los valores BYG y ECPH fueron más competitivos que ’Hashemi’. BYG tuvo un peso seco sobre el suelo, peso seco de raíces, número de macollos, área foliar y altura de plantas significativamente superiores que ECPH cuando se cultivan con ’Hashemi’. Este experimento confirmó que BYG fue más competitivo que ECPH contra ’Hashemi’.