Maize In Iran Research Articles

Mycoflora of Maize Harvested from Iran and Imported Maize

The natural occurrence of fungal contamination was evaluated in stored maize in three different agro-ecological zones (Iran, Brazil and China). A total of 45 samples were analyzed and 685 fungal isolates were identified. The most frequent isolated fungi from maize originated from Iran, Brazil and China were Fusarium sp. (17.3, 17.9 and 37.1%), Aspergillus sp. (9.3, 17.4 and 19.7%),Penicillium sp. (5.8, 15.2 and 17.6%), Rhizopus sp. (2.4, 3.2 and 3.5%), Mucor sp. (1.1, 1.6 and 1.3%), Cladosporium sp. (1.6, 1.9 and 1.9%), Alternaria sp. (1.1, 1.6 and 1.3%), Geotrichum sp. (0, 0 and 0.3%), Acromonium sp. (0.5, 0.8 and 0%) and Absidia sp. (0, 0.8 and 0.5%), respectively. Significant difference was observed between the frequency of fungal isolates of Iranian maize and foreign products (p < 0.0005). Maize mycoflora profiles showed that Fusarium verticillioides and Aspergillus flavus prevailed in 30.7 and 13.3% of the samples from China, in 12 and 5.3% of the samples from Iran and 11.7 and 11.5% of the samples from Brazil, respectively. There were significant differences in the frequency of Fusarium verticillioides in Chinese maize with other countries products (p < 0.0005) and that of Aspergillus flavus in Iranian maize with other countries (p < 0.002). The results emphasize that farmers and consumers should be alerted to the danger of fungal contamination in maize.

Human Dietary Exposure to Fumonisin B1 from Iranian Maize Harvested During 1998–2000

Fumonisin B(1) (FB(1)) is the most abundant of the fumonisin mycotoxins, mainly produced in maize by F. verticillioides and F. proliferatum. A previous study on the FB1 contamination of maize harvested in Mazandaran and Isfahan Provinces of Iran in 1998 and 1999 demonstrated contamination in both provinces. This present study was undertaken to further investigate the variation in levels of contamination and to estimate possible levels of human exposure to fumonisins in Iran. The mean level of FB(1) in 49 visually healthy maize samples collected from Mazandaran Province during 2000 was 6.14 mg/kg, which is higher than that found during 1998 and 1999 (2.27 and 3.18 mg/kg, respectively). Although these levels are higher than the Iranian legislative limits for fumonisins in maize intended for humans, the relatively low estimated consumption of maize in Iran (3.3 g/person/day) implies that average exposures (0.011 and 0.215 microg/kg body weight/day in Isfahan and Mazandaran, respectively) are within the provisional maximum tolerable daily intake of 2 microg/kg body weight/day set by the Joint FAO/WHO Expert Committee on Food Additives. Nevertheless, certain sections of the population who may consume higher amounts of maize or who may replace all or some of their consumption of other cereals with maize, could well exceed this limit.

Use of SSR data to determine relationships and potential heterotic groupings within medium to late maturing Iranian maize inbred lines

Information on germplasm diversity and relationships among elite materials is fundamentally important in crop improvement. The main objectives of our study were to: (1) determine the level of genetic diversity within and relationships among the most commonly used medium to late maturing Iranian maize inbred lines using simple sequence repeat (SSR) markers, and to (2) suggest heterotic groups among the lines using genetic distance as measured by the SSR markers. Fifty-six inbred lines, which are the most commonly used in maize breeding programs in Iran, and two lines from CIMMYT, Mexico (used as checks) were fingerprinted with 46 SSR markers. A total of 225 alleles were detected. The UPGMA clustering grouped the Iranian inbreds into four clusters (in addition to one group which included only the CIMMYT control lines), which were consistent with the pedigrees or known information about source materials. The highest distance was found between the cluster of Reid Yellow Dent related lines and the cluster of Lancaster Sure Crop related lines, and this pattern has produced some of the highest yielding hybrids in Iran. Other heterotic patterns based on the SSR markers are suggested, but must be field tested to confirm what appears to be promising alternative heterotic patterns.

Survey of the natural occurrence of zearalenone in maize from northern Iran by thin-layer chromatography densitometry

During September 2000, forty samples of preharvest maize from the province of Mazandaran, north Iran, were randomly collected. Samples were analysed for zearalenone (ZEA) by a thin-layer chromatograpy (TLC) method (AOAC Official Method). ZEA was extracted with chloroform, purified through a chromatographic column containing silica gel, separated on a TLC plate and quantified by densitometry. The analytical method was validated and was adequately reliable and sensitive. The mean recovery rate of ZEA from spiked samples was 92%. The absolute amount of ZEA standard detectable on a TLC plate was 20 ng, giving a limit of detection (LOD) of 100 ng g-1. In some samples, it was shown that aflatoxins interfere with ZEA. Therefore, to remove this interference, the TLC mobile phase was changed. Data revealed that three of 40 (7.5%) maize samples contained ZEA in the range 100–212 ng g-1, with a mean of 141 ± 51 ng g-1. This study, which is the first report of ZEA occurrence in Iranian maize, showed that the ZEA level in maize of Mazandaran province was lower than maximum limit for this mycotoxin in Iran.

Purification and Serology of the Iranian Maize Mosaic Rhabdovirus1)

AbstractLeaves of maize infected with the Iranian maize mosaic rhabdovirus (IMMRV) were homogenized in 0.1 M citrate‐0.04 M Na2SO3 buffer, pH 5.4, containing 10 % sucrose and the extract was subjected to low speed and high speed centrifugation followed by resuspension in 0.05 M potassium phosphate buffer, pH 7.2, containing 10 % sucrose. Partially purified preparation was obtained by density‐gradient centrifugation, removal of the virus zones and their concentration by high speed centrifugation. Two virus specific bands were observed in density‐gradient columns. An antiserum with a titer of 128 was prepared by injecting partially purified virus into rabbits. In agar‐gel‐diffusion tests, the antiserum produced one or two precipitin lines against diseased maize extract but none against healthy maize extract. IMMRV was not related to barley yellow striate mosaic (BYSMV), cereal chlorotic mottle (CCMV), Cynodon chlorotic streak (CCSV), Festuca leaf streak, and maize mosaic (MMV) viruses as well as to two unidentified rhabdoviruses occurring in wheat and Bermuda grass in the vicinity of Shiraz, when these viruses were tested against IMMRV antiserum in agar‐gel‐diffusion and enzyme‐linked immunosorbent assay. Likewise, IMMRV did not react with antisera to BYSMV, CCMV, CCSV and MMV in agar‐gel‐diffusion tests. IMMRV appears to be different from most reported rhabdoviruses of cereals.