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Abstract: Talaromyces flavus a fungal antagonist, was isolated from soil samples collected from potato fields in Varamin and Karaj districts, Tehran province, Iran. Antagonistic effects of T. flavus isolates against Verticillium albo-atrum, the causal agent of potato wilt disease were investigated in the laboratory and greenhouse conditions. T. flavus colonies were recovered after three weeks from soil samples cultured on selective medium. Antagonistic effects of volatile and non-volatile extracts of T. flavus isolates on V. albo-atrum growth were investigated in the laboratory and five that caused higher growth inhibition of V. albo-atrum, were selected for greenhouse experiments. Infection index was compared in the greenhouse in a split plot trial with five isolates applied to soil, seed, or both arranged in a randomized complete block design with four replications. The minimum infection index was observed when seed were treated with T. flavus with the most effective isolate being Tf-Po-V-52. On seed, the minimum infection index was observed with Tf-Po-V-50. The most effective T. flavus isolate was also evaluated in a field experiment. Results indicated that infection index in seed treatment contained this isolate was 0.15 whereas that of control was 3.5. The overall results of this study showed that it may be possible to manage potato Verticillium wilt disease effectively by using T. flavus, a biocontrol fungus. [Copyright &y& Elsevier]

Abstract: Aerobic rice systems, wherein the crop is established via direct-seeding in non-puddled, non-flooded fields, are among the most promising approaches for saving water and labour. However, aerobic systems are subject to much higher weed pressure than conventionally puddled transplanted rice (CPTR). Experiments were conducted for 2 years to develop effective and economical methods for managing weeds in aerobic rice grown by direct-seeding or transplanting on flat land or furrow-irrigated raised-bed systems (FIRBS). Total weed dry weight and weed density were lower with CPTR and highest with aerobic direct-seeded rice on a FIRBS (ADSB), followed by aerobic direct-seeded rice (ADSR). In terms of weight grassy weed constituted 78–96% of total weed weight in all systems of rice establishment. Loss of grain yield of rice due to weed competition ranged from 38% to 92%, being the highest in ADSB. Both weed density and dry weight were negatively correlated with rice grain yield. ADSR treatment produced yield and net economic returns similar to CPTR treatment when weeds were controlled. Pretilachlor with safener at 500ga.i.ha−1 applied 3 days after sowing (DAS)/ days after transplanting (DAT) followed by chlorimuron+metsulfuron at 4ga.i.ha−1 applied 21DAS/DAT followed by hand-weeding at 35DAS/DAT could effectively control all the weeds. The next best treatment was cyhalofop-butyl at 120ga.i.ha−1 applied 14DAS/DAT followed by chlorimuron+metsulfuron at 4ga.i.ha−1 applied 21DAS/DAT followed by hand-weeding at 35DAS/DAT. The ADSR was as effective as conventionally puddle-transplanted rice in attaining higher rice grain yield and net returns when weeds were kept under control. [Copyright &y& Elsevier]

Abstract: A herbicide safener AD-67 inducible cDNA was identified in an indica rice variety 9311 by mRNA differential display. The transcript was increased 6 h after sprayed with the safener solution, and 4 days later, the expression still could be detected. The fragment was recycled from the poly-gel and sequenced, and homologous analysis revealed the cDNA was 100% identical to some ESTs and cDNAs in rice database, and the amino acid sequence was 60–84% homologous to those of the Yippee genes in several eukaryotes. The fragment was extended to the whole long cDNA, and thus a primer pair was designed. RT-PCR analysis for the designed primer supported the induction result. [Copyright &y& Elsevier]

Benoxacor (BN) is a highly effective antidote of dichloroacetamide herbicides generally used to protect crops from herbicidal damage. As a commonly used agrochemical, this herbicide antidote is continuously discharged in watercourses thus causing toxicity to aquatic organisms, and ultimately leading to contamination of the food chain. To date, its potential toxicity to the cardiac development of aquatic organisms has not been evaluated. In the present study, we have selected the zebrafish as a model to study the impact of BN on embryonic developmental and cardiac toxicity. The zebrafish embryos were exposed in 0.5, 1.0 and 2.0 mg/L BN from 5.5 to 72 h post-fertilization (hpf). The results indicated that the exposure to BN led to increased mortality and diminished heart and hatching rates in the embryos. BN exposure also brought pericardial edema (PE) and linear stretching of heart. Besides, exposure to BN induced an excessive accumulation of reactive oxygen species (ROS) in the zebrafish embryos and abnormal activities of the antioxidant enzymes, including catalase (CAT) and malondialdehyde (MDA). Moreover, exposure to BN caused serious cardiac toxicity of the embryos, accompanied by abnormality of heart development- and apoptosis-related genes. Surprisingly, astaxanthin (ASTA), as a common antioxidant, was found to be able to partially rescue the cardiac toxicity caused by BN, which indicated that ROS are probably the major reason for the resulting cardiotoxicity in zebrafish embryos. Our results suggest the need for a comprehensive safety evaluation of the regular consumption of benoxacor, which provides scientific basis for the development of health standards and assessment of potential risk in aquatic organisms or even human. • Benoxacor increased mortality, decreased heart and hatching rates in the embryos. • Benoxacor induced pericardial edema, led to linear stretching of heart. • Exposure to benoxacor induced oxidative stress in zebrafish embryos. • Benoxacor caused changes in the transcription levels of heart development genes. • Astaxanthin was able to partially rescue cardiac toxicity caused by benoxacor. [ABSTRACT FROM AUTHOR]