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Exogenous salicylic acid treatments enhance tolerance to salinity of wheat (Triticum aestivum) plantlets
34-38Views:130Salt stress, an abiotic stress, determines modifications of some biochemical indicators, like, antioxidant enzymes, proline (amino acid
accumulate in higher plants under salinity stress) content, and some physiological processes including: plant growth and development. In
this paper we studied the influence of exogenous treatment of wheat seeds, with 0.1 mM salicylic acid (SA) solution, in the plant response to
salt stress. The treatment was applied by presoaking the seeds in the treatment solution for 12 hours before germination. The results showed
that exogenous 0.1 mM SA solution, administrated to the wheat cariopses significantly ameliorated the negative effect of salt stress in first
week of germination in laboratory conditions. -
The role of some elicitors in inducing chilling stress resistance in apricot fruit
27-32Views:163This study aimed to study the role of 2 mM salicylic acid and 0.2 mM methyl Jasmonic acid in reducing the chilling injuries on two different apricot varieties fruits (Bergarauge and Flavor cot). These treatments were applied for apricot fruit directly after harvest after measuring the zero time data. Then the fruit were stored at 1 oC for three weeks and were examined 7 day periodically, other group of fruit was stored at 1 oC for 15 days then transport to room temperature and examined after 4 and 8 days. The fruit samples were collected at each examination time, and the measurements containing the fruit firmness (Kg cm-2), chilling and decay index, membrane electrolyte leakage, total phenol content and phenylalanine ammonia lyase mechanism (PAL) activity. The results showed that there are no obvious differences between the tested varieties and the differences may back to genetic variations and they took the same trend for most of measurement after treated with SA and MJ. SA and/or MJ treated fruit achieved low percentage of fruit softening in comparison to water treated fruit. At the same time the chilling and decay index showed that the SA and/or MJ reduced the decay or breakdown symptoms in either tested varieties. The treated fruit with those elicitor help the fruit to keep about stable phenol content while water treated fruit lose the phenol content sharply at early storage and this stable level of phenol my because of the ability of those chemical to raise PAL activity in treated fruit.
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Studies on the Suitability of Different Mould Media Compositions for the Mycological Evaluation of Hay Samples
34-38Views:85t evaluating mould contamination of hay samples in more than the half of the cases Mucor spp. (and Trichoderma spp. in a smaller extent) overgrew slower developing moulds, spoiling the assessment of total mould CFU and the detection of fastidious organisms, among others the toxinogenic Fusaria. In parallel microbiological evaluation of hay samples comparing to the ISO 7954 medium as reference a) the overgrowth inhibiting effect of Rose Bengal (ISO 7954-RB); b) the combined inhibiting effect of Rose Bengal and Dichloran (dichloro-mononitroaniline) in DRBC; c) the inhibition of Dichlorane in ISO 7954 (ISO 7954-DC); d) the lowering of nutrient levels to 1/4 (1/4 N ISO 7954, 1/4 N-DRBC and 1/4 N-DC); e) the inhibiting effect of dinitro – salicylic – acid (DSA), a reducing sugar binding compound, as a potential growth inhibitor (RBC-DSA) were studied. The results showed, that 1) MSZ-ISO 7954 medium codified by the official method was unsuitable for the detemination of mould count and for the detection of toxinogic spp. in hay samples. In half of the cases the overgrowth of Mucor has spoiled CFU enumeration and recognition of toxinogenic moulds; 2) Inhibitor supplemented DRBC medium (King et al., 1979) enabled early CFU enumeration by uniforming colony sizes and by efficient suppression of Mucor, but the pink background colour of the medium was disturbing the observation of tints of conidia, which were characteristical to toxinogenic moulds like Fusaria. The hypha-staining property of Rose Bengal did not prove very important; 3) According to the recent stage of our studies, the ISO 7954-Dichloran combination can be recommended for the mycological evaluation of hays and dried roughages. CFU can be enumerated early, Mucor suppressed in the same extent as with DRBC and colours are easily observable; 4) 2-4-Dinitrosalicylic-acid (DSA) proved unsuitable as inhibitor, for its poor efficiency and for its intense yellow background coulour.