Soil moisture and soil temperature affect pre-harvest infection with Aspergillus flavus and production of aflatoxin. The objectives of our field research in Niger, West Africa, were to: (i) examine the effects of sowing date and irrigation treatments on pod yield, infection with A. flavus and aflatoxin concentration; and (ii) to quantify relations between infection, aflatoxin concentration and soil moisture stress. Seed of an aflatoxin susceptible peanut cv. JL24 was sown at two to four different sowing dates under four irrigation treatments (rainfed and irrigation at 7, 14 and 21 days intervals) between 1991 and 1994, giving 40 different 'environments'. Average air and soil temperatures of 28-34 8C were favourable for aflatoxin contamination. CROPGRO-peanut model was used to simulate the occurrence of moisture stress. The model was able to simulate yields of peanut well over the 40 environments (r 2 = 0.67). In general, early sowing produced greater pod yields, as well as less infection and lower aflatoxin concentration. There were negative linear relations between infection (r 2 = 0.62) and the average simulated fraction of extractable soil water (FESW) between flowering and harvest, and between aflatoxin concentration (r 2 = 0.54) and FESW in the last 25 days of pod-filling. This field study confirms that infection and aflatoxin concentration in peanut can be related to the occurrence of soil moisture stress during pod-filling when soil temperatures are near optimal for A. flavus. These relations could form the basis of a decisionsupport system to predict the risk of aflatoxin contamination in peanuts in similar environments. #

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During a survey of soil nematodes in Iran, a population of a species belonging to the order Mononchida was recovered. The new species, Paramylonchulus iranicus sp. n. is characterized by body length (1292–1535 μm in females and 1476–1670 μm in males), c (20.2–29.0 in females and 19.9–27.4 in males), buccal cavity length (23.0–26.0 μm), post vulval uterine sac length (135–162 μm), spicule length (46.0–50.0 μm), gubernaculum length (8.0–11.0 μm), and tail length (49.0–70.0 μm in females and 55.0–73.0 μm in males). Canonical discriminant analysis clearly separated P. iranicus sp. n. from the closely related species Paramylonchulus based on the important morphometric characters of females and males. A molecular study of the 18S rDNA region of P. iranicus sp. n. places this population in a well-supported clade with other species of the genus.

Metabolites from biomass of Trichoderma harzianum were used for green synthesis of zinc oxide nanoparticles (ZnONPs) from zinc nitrate (ZnNO3) and GC/MS analysis of metabolite was performed. Then, the antifungal activity of synthesized ZnONPs was evaluated against Fusarium oxysporum under the laboratory and greenhouse conditions. Results were compared to different concentrations of Iprodione + Carbendazim (Rovral-TS®) fungicide. Synthesized ZnONPs were characterized by ultraviolet-visible spectrometry (UV-Vis), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and fourier transform infrared spectroscopy (FTIR). UV-Vis spectra showed an intense peak at 339 nm. X-ray diffraction pattern showed the crystalline nature and purity of the ZnONPs. FTIR revealed various functional groups including phenols, ketones, aldehydes, aliphatic and primary amines, nitriles, alkanes and alkynes in synthesized ZnONPs. Size of ZnONPs determined in the range from 25–60 nm. Based on atomic absorption spectroscopy, foliar application of synthesized ZnONPs, led to considerable accumulation of zinc in the leaves and suitable for compensate zinc deficiency. Some growth factors including root length, root volume, stem length, stem diameter and number of leaves improved in the treatments containing metabolite of T. harzianum, ZnNO3 and ZnONPs. Complete inhibition of mycelia growth of F. oxysporum was observed in 100 µg/ml concentration of ZnONPs in the laboratory conditions and disease percentage significantly reduced in the greenhouse conditions, indicated that green synthesized ZnONPs gave better results in low concentration than the fungicide. Therefore, application of green synthesized ZnONPs could be recommended as effective alternative and eco-friendly method for crop protection instead chemical fungicides.