الفهرس 
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Abstract
Maximizing the benefits of mycorrhizae as a biofertilizer for the medicinal plants coriander and anise was the main goal of this study. To achieve this goal, the objectives of this work were to determine the best levels of fungicides, nitrogen fertilization, and organic matter for mycorrhizal activities. Two methods of mycorrhizal inoculation were also evaluated for their effect on the growth and activity of mycorrhizae in the rhizosphere of the tested medicinal plants. These experiments were carried out in sandy and clay soils in the Department of Agricultural Microbiology, Faculty of Agriculture, Minia University, during 2004/2005 and 2005/2006 seasons under green house conditions.
The above mentioned objectives were achieved through four main experiments, which can be briefly described as follow:
The first experiment investigated the effect of different fungicides concentrations on the growth of coriander and anise plants in the presence or absence of mycorrhizae. This experiment also included the effect of fungicides and inoculation wi`th mycorrhizae on the microbial community in the rhizosphere of coriander and anise plants. The experiment included the application of rizolex fungicide at rates of 0.012, 0.024 and 0.048 mg/pot and application of cobax fungicide at rates of 12.50, 25.00 and 50.00 mg/pot
The second experiment investigated the effect of chemical nitrogen fertilization on the growth of coriander and anise plants in the presence or absence of mycorrhizae. This experiment included the application of ammonium nitrate (33.5%-N) at rates of 0.3. 0.6, 0.9 and 1.2 gm/pot, which represent 37.5, 75, 112.5 and 150 kg/feddan and also represent 25, 50, 75 and 100 of the recommended dose.
The third experiment investigated the effect of compost application on the growth of coriander and anise plants in the presence or absence of mycorrhizae. This experiment included the application of the Nile compost at rates of 16, 32, 48 and 80 gm/pot representing 2, 4, 6 and 10t/feddan.
The fourth experiment investigated the effect mycorrhizal inoculation method on the growth of coriander and anise plants. The broadcasting and the pellet application techniques were evaluated.
The most important general results can be summarized as follows:
1-The fungicides experiment:
Heights and root lengths of coriander and anise plants were significantly decreased when rizolex and cobax fungicides were applied at high concentrations (0.048 mg/pot for rizolex and 50 mg/pot for cobax) at all sampling times in both of clay and sandy soils. However the inoculation treatment with VAM mycorrhizae improved the adverse effect of the tested fungicides. Application of mycorrhizae balanced this disturbance and the plants grew normally even in the presence of the fungicides which were necessary to be added to control the non- desired fungi.
Nearly most of the fungicides levels significantly decreased the dry weight of shoot, root and total dry weight of coriander and anise in both of the two soils. Inoculation with mycorrhizae was necessary to avoid the hazard effect of fungicides on the growing plants in both of the clay and sandy soils. Addition of rizolex and cobax fungicides even at low concentrations adversely affected the seed yield, percentage of local mycorrhizal infection, percentage of nitrogen and protein in seeds, percentage of nitrogen in plants and percentage of phosphorus in plants in both of the clay and sandy soils. Inoculation with VAM mycorrhizae successfully made a rebalance of these effects. In the presence of added mycorrhizae, the rizolex and cobax fungicides can be added to practice their job against the non-desired fungi provided that their concentrations do not exceed 0.012 mg/pot and 12.50 mg/pot for rizolex and cobax respectively.
Treatment the growing plants with the fungicide rizolex, increased the total bacterial counts in a rhizosphere soils of different coriander than those of the control non treated plants or the anise in both of the clay and sandy soils during different growth stages. Increasing the rizolex concentration up to 0.048 mg/pot sharply declined the total bacterial number. The numbers of fungi in rhizophere of coriander and anise plants were higher counts in rhizophere of coriander during different growth phases were higher than those in the rhizophere of anise in both of the tested soils.
2-Nitrogen fertilization experiment:
Heights, root lengths and dry weight of shoots and roots of coriander and anise plants were significantly increased by inoculation with mycorrhizae in the presence of nitrogen at concentration of 0.9 gm ammonium nitrate /pot (representing 112.5 kg/feddan) in clay and sandy soils. This is means that maximizing the benefit effects of mycorrhizae required addition of nitrogen provided that it¬s concentration does not exceed 0.9 gm ammonium nitrate /pot.
The interaction effect between N-fertilizers and inoculation with mycorrhizae on the above parameters was significant only with application of 0.9 gm ammonium nitrate /pot for coriander and anise plants in the clay and sandy soils. Nitrogen fertilizers significantly affected the percentage of infection and seed yield of coriander and anise plants in the clay and sandy soils. Inoculation with mycorrhizae led to a high significant increase in the percentage of infection and seed yield of coriander and anise plants as compared with non- inoculated in the two soils. However the maximum benefits of mycorrhizae were obtained when the growing plants were inoculated with VAM mycorrhizae in addition to fertilization with 0.9 gm ammonium nitrate /pot in the two soils. This kind of treatment also had positive effects on percentage of nitrogen and phosphorus in the plants, and percentage of nitrogen, phosphorus and protein in seeds in both of the clay and sandy soils. The interaction effect between N-fertilizers and inoculation with mycorrhizae on the above parameters was significant when the fertilization level was 0.9 gm ammonium nitrate/pot in the clay and sandy soils.
3-compost experiment:
Application of compost at rate of 32 gm/pot (representing 4 t/feddan) for coriander and anise plants in the clay soil together with the mycorrhizal inoculation gave the best results regarding the plant height, root length, dry weight of shoots and roots, percentage of infection, seed yield, percentage of nitrogen and phosphorus in the plants, percentages of nitrogen, phosphorus and protein seeds. The sandy soil needed compost at rate of 80 gm/pot (representing 10t/feddan) to give similar results. The interaction effect of compost levels and inoculation with mycorrhizae on the above parameters of coriander and anise plants in the clay and sandy soils was significant.
4-Methods inoculation experiment:
Inoculation of coriander and anise plants with mycorrhizae in the form of pellets was much better and had a significant positive effects on plant height, root length, dry weight of shoots and roots, percentage of nitrogen and phosphorus in the plants, percentage of protein, percentage of infection and seed yield as compared with broadcasting inoculation method. These results were achieved in both of the clay and sandy soils.
Recommendations
Based on the above explained results four main recommendations can be introduced To Whom It May Concern to maximize the benefits of the mycorrhizal fungi as follow:
1- If the addition of rizolex and cobax fungicides to the coriander and anise plants can not be avoided they should not be added at concentration more than 0.012 mg/pot and 12.501` mg/pot respectively.
2- The optimum nitrogen fertilizer rate in is 0.9gm ammonium nitrate/pot 33.5% nitrogen which represent 112.50 kg/fedden, respectively.
3- The optimum compost application rates are 32gm/pot representing 4t/feddan in the clay soil and 80 gm/pot representing 10t/feddan in the sandy soil.
4- Using the mycorrhizal inoculum in the form of pellets is much better than using the broadcasting inoculation method.