@Article{, title={COMBINING EFFECT OF CHEVALIER HERBICIDE AND SUNFLOWER RESIDUE ON ARBUSCULAR MYCORRHIZA تأثير مبيد الشيفالير مع مخلفات زهرة الشمس في الفطريات الجذرية الشجيرية}, author={H. M. Aboud هادي مهدي عبود and I. Sh. Alsaadawi ابراهيم شعبان السعداوي and S. N. Al-Eqaili سراء نصيف العكيلي}, journal={IRAQ JOURNAL OF AGRICULTURAL RESEARCH مجلة الزراعة العراقية البحثية}, volume={19}, number={2}, pages={189-197}, year={2014}, abstract={The effect of different rates of sunflower residues alone or in combination with lower dose of chevalier herbicide on arbuscular mycorrhiza associated with wheat roots was investigated during the growing season of 2012-2013. The quantitative level of total phenolics released from sunflower residues in soil was also determent by using ferulic acid as a standard phenolic acid. Results revealed that total phenolics in field soil significantly increased after incorporation of sunflower residues and reached the maximum concentration at 4 weeks of residues decomposition, then decreased significantly at 6 weeks and vanished at the end of the second month. However, the number of spores in field soil amended with sunflower residues was significantly increased at 2, 4 and 6 weeks of residue decomposition compared to control treatment (without sunflower residue). At flowering stage, it was found that sunflower residues incorporated in field soil at 3 and 6 t ha-1 increased number of spore by 15.68 and 23.46 % over control, while it was decreased significantly when chevalier was applied at the label dose. Chevalier at reduced (50% of the label rate) rate applied to plots amended with sunflower residue at 3 t ha-1 scored spore number significantly lower than that of the control treatment, but when the reduced dose was applied to plots amended with higher residues rate, the number of spores was significantly increased over the control. Sunflower residues incorporated in to field soil at rates of 3 and 6 t ha-1 increased rate and intensity of colonization by 48, 53% and 50, 52% of control respectively. Application of reduced dose of herbicide on plants grown in plots amended with sunflower residues significantly increased rate and intensity of colonization compared to the control.

Soil an important component of the ecosystem, serves as a medium for plant growth through the activity of microbial communities. This soil microbial communities (like bacteria, fungi and actinomycetes) play critical role in litter decomposition and nutrient cycling, which in turn, affect soil fertility and plant growth (8,18,21,26).However, soil microorganisms are greatly influenced by factors including the application of herbicides (17),which are applied in modern agricultural practices to attain optimum crop yields (28). Arbuscular mycorrhiza (AM) are beneficial fungi found in soil existing symbiotically with plant roots. They enhance the growth of many plant species by increasing the efficiency of nutrient and water uptake. Since AM fungi grow and develop in soil ecosystem, they are likely to be exposed directly to toxicants or chemicals such as pesticides use in agricultural practices, which may be inhibitory to their} }