Role of different nirogen fertilizer levels on the development and effectiveness of VA mycorrhizal fungi on maize plants

The effects of five rates of ammonium sulfate [0, 22.5, 45, 90 and 180 kg N fed-1] on the development and effectiveness of vesicular- arbuscular [VA] mycorrhizal fungi on maize were studied in a clay loam soil. N fertilization at the rates of 22.5 and 45 kg N fed-1 increased significantly the percentage of mycorrhizal root colonization in both mycorrhizal inoculated and un-inoculated plants. Increasing the rates of nitrogen fertilization above 45 kg N fed-1 had a negative effect on root colonization by VA mycorrhizal fungi. A significant increase in dry matter production, N and P uptakes of maize plants was obtained as the rate of nitrogen fertilization increased. At a low N fertilization rate [below 45 kg N fed-1], inoculation with VA mycorrhizal fungi increased the dry matter production, N and P uptakes of maize plants. However, there was no significant response in dry matter yield, N and P uptake of maize plants inoculated with VA mycorrhizal fungi as nitrogen fertilized increased above 45 Kg N fed-1

Response of chickling vetch [lathyrus sativus L] and forage peas [pisum spp] to inoculation with rhizobium leguminosarum in north Sinai coastal soils

Field experiments were conducted in sandy soil at Rafah, north sinai, to study the performance of two Rhizobium leguminosarum strains [TAL 634 and F9] with vetch, grasspea [Lathyrus sativus] and forag peas [Pisum spp.]. Inoculation of both crops with these strains, either singly or in combination, induced significant increases in plant dry weight, N2 fixation and seed yield. No significant differences, in plant N content or seed yield, were obtained between the two rhizobial strains and/or their mixtures for both crops. The competitive ability of inoculant strains differed with the host plant. Strain TAL 634 was more competitive than strain F9 with chickling vetch. In double strain inocula, strain TAL 634 occupied 40% of nodules versus 15% for F9. With forage peas, strain F9 was more competitive than strain TAL 634. The strain F9 occupied 45% of nodules versus 30%for strainTAL634

Competition between three bradyrhizobium japonicum strains as affected by strain proportion in inocula

Double strain combinations of Bradyrhizobium japonicum strain USDA 110 with strains USDA 138 or TAL 379 mixed in different ratios [1 : 1. 1 : 5, 1 : 10, 1 : 25. 1 : 50, and 1 : 100] were used as inocula for soybean Crowford. Modulation of soybean plants were not affected by changes in ratios of inoculant strains. Increasing the ratio of inocularil strains 138 or 379 to strain 110 resulted in a gradual decrease in plant dry weight, N content and seed yield. A significant decrease in plant dry weight, N content and seed yield was obtained when the ratio exceeded 25 : 1. Strain USDA 110 was more competitive than strain USDA 138 or TAL 379. Strains, USDA 138 or TAL 379 from nodules, reached the same level of USDA 110 nodule occupancy at ratio 25 : 1 for both strains

Field performance of three rhizobium japonicum strains with two soybean cultivars

A field experiment was conducted in a clay loam soil to study the performance of three R. japonicum strains; USDA 110, USDA 138 AND TAL 379; in relation to their N2 fixing potential and competitive relation on two soybean cultivars [Clark and Calland]. Inoculation of soybean cultivars with these strains either singly or in combination induced significant increase in plant dry weight, N2 fixation and seed yield, strain USDA 110 was the most efficient strain in N2 fixation and in increasing seed yield on both cultivars followed by USDA 138, while TAL 379 was the least effective strain. The two soybean cultivars were similar in their response to inoculation. No significant difference in seed yield were observed between Clark and Calland cultivars. The interaction between inoculant strain and soybean cultivar was not significant

Effect of soil conditioners on some biological properties of sandy soil and the diversity of microbes involved in their biodegradation

The application of bitumen and ureaformaldehyde at the two low application rates stimulated the total bacterial, fungal and Azotobacter counts in sandy soil. The higher rate of conditioners applications, however, delayed the proliferation of soil microorganisms for 60 days. The application of bitumen and ureaformaldehyde to sandy soil planting with peanut inoculated with Rhizobium spp. Induced insignificant increase in nodulation, dry matter yield and N accumulation except the higher application rate which resulted in slight decrease in nodulation. Generally, no marked retardation of nodulation or N2 fixation was noted as a consequence to the conditioner application. The bacterial genera contributing to the biodegradation of bitumen and ureaformaldehyde in the sandy soil are Bacillus, Micrococcus, Pseudomonas, Flavobacterium, and Streptomyces. Bacillus was the most dominant genus for both soil conditioners

Field assessment of the interaction between seven soybean cultivars and three Rhizobium japonicum strains

A field experiment in a clay loam soil was conducted to evaluate the interaction between seven soybean cultivars and three Rhizobium japonicum strains. The associations of soybean cultivars with strain USDA 110 were more efficient compared to those with strain USDA 138 or TAL 379. The more efficient symbiosis was observed between strain USDA 110 with Cumberland and Pella cultivars. However, strain USDA 138 gave the best nodulation and N2 fixation with Williams 79 and Calland cultivars. Whereas strain TAL 379 was better with Corsoy and Sprite than with other cultivars. A positive yield response to inoculation was noted with strain USDA 110, being the superior strain all tested cultivars followed by strain USDA 138. The Calland, Pella and Williams 79 cultivars gave the highest yield production. The competition studies revealed that strain USDA 110 was more competitive than either USDA 138 or TAL 379. Strain USDA 110 showed higher competitive ability with Cumberland, Pella and Calland cultivars and comparatively lower competitive ability with Corsoy and Sprite cultivars. Strain USDA 138 occupied 40 and 45% of nodules formed on Calland and Williams 79 cultivars, respectively versus 20% of nodules formed on Corsoy and Pella cultivars. The total nodule occupancy of strain TAL 379 amounted 40% on Sprite and Corsoy cultivars versus 20% on other soybean cultivars

Symbiotic nitrogen fixation by two lentil cultivars in relation to rhizobium strain, competition and irrigation rates

Two Rhizobium Leguminosarum strains TAL 638 and Nitragin 92 A3 were studied in their relation to fix atmospheric nitrogen with two lentil cultivars. The experiment was conducted in a Delta Nile clay loam soil using two rates of irrigation. regardless the irrigation. regimes, the inoculation of lentil with these strains either singly or in combination induced significant increase in plant dry weight. nitrogen fixation grad seed yield. Giza 370 cultivar in symbioses with any of the strains was superior in nitrogen accumulation and seed yield than Giza 9 cultivar. However. the strain X varicty interaction was not significant. The nitrogen fixation and thee yield of both lentil cultivars were significantly affected by water regime. The frequent irrigation resulted in higher plant dry weight. N accumulation and seed yield with both cultivar The inoculum strain outcompeted the resident rhizobia. Between 72-92% of nodules were occupied by the strains used as single inoculum. In double, strain inocula, R. leguminosarum strains, TAL 638 and Nit. 92 A3 were equailly, competitive on both cultivars under the two irrigation regimes. The incidence of double strain occupancy within the nodules collected from the double strain inocula ranged between 0 to 38%

Biological control of rhizoctonia solam using trichoderma viride and its relation to symbiotic nitrogen fixation by faba bean

A pot experiment was carried out using a clay loamy soil to study the efficacy of Trichoderma viride as a biocontrol for Rhizoctonia solani as well as its effect on biological nitrogen fixation by faba bean. Soil inoculation either with R. solani, Tl viride or in combination had no effect on total microbial counts in the rhizosphere soil of the faba bean. These treatments, however, enhanced the proliferation of fungal population in the rhizosphere. The infection with R. Solani induced retardation of nodulation and symbiotic nitrogen fixation. Control of the disease by T. viride resulted in normal nodulation and nitrogen fixation patterns as produced by the healthy [non infected] plants

Nitrogen fixing capacity of eleven clover cultivars modulated by native rhizobia

Berseem clover, Trifolium alexandrinum, is the main winter forage legume in Egypt. A national breeding and selection program is under way in order to upgrade the productivity of this crop. 11 clover cultivars were evaluated for their N-fixing capacity when nodulated by native rhizobia. 2 cultivars, Giza 2 and Seds 5 gave small nodular tissue, dry matter yield and low nitrogen content. Some other cultivars, Upper Egypt 1 and Giza 52 were distinguished by exhibiting high N-fixation and dry matter yield. The response of different cultivars to N-fertilization was different. However, most of the tested cultivars benefited from N-fixation in the second and third cuts rather than the first cut

Field evaluation of biogas manure as a fertilizer for corn

A field experiment on corn [Zea mays L.] was conducted in silty clay soil to evaluate the effect of biogas manure on corn yield and nutrients uptake [N, P, K, Fe, Zn, Mn and Cu] in comparison with farmyard manure as well as regular NPK fertilizer. The application of biogas manure at rate of 20 ton/acre significantly increased seed yield and N, P, K, Fe, Zn, Mn and Cu uptake than did the 20 t farmyard manure or 10 t biogas manure. The fertilization with 20 t biogas manure/acre also significantly increased P, K, Fe and Mn uptake as compared with their uptake from the regular NPK treatment. No significant difference in seed yield was recorded between the NPK treatment and the 20 t biogas manure. The supplementation of 20 t biogas manure treatment with 45 kg N/acre significantly increased nutrients uptake and seed yield over the treatment with 20 t biogas manure alone

Effect of soil conditioners on nodulation and seed yield of faba bean grown in newly reclaimed area

In a field trial, sandy soil from Salhia project [Entisols, Quartzipsamments], soil taxonomy [1975], was treated with bitumen, polyacrylamide, urea-formaldehyde and uresol at rates of 50, 20, 75 and 40 g/m2 respectively. The germination faba bean seedlings after 15 days increased in the following order: Bit >PAM >Ur >UF >Cont. While, at 30 days, it changed to UF >Bit >Ur >PAM >Cont. The application of soil conditioners to sandy soil induced significant increase in the nodulation, dry matter and N-content of faba bean plants [after 75 days]. The yield of seeds increased by 20, 18, 15 and 11% as a result of treating the soil with UF, Bit, PAM and Ur respectively. Nitrogen balance revealed higher gain of N due to soil conditioner treatments. Bitumen emulsion exerts the most beneficial effect on symbiotic N fixation than other conditioners containing nitrogen

Antimicrobial agents in Egyptian folk medicine

Aninvestigation was made into the presence of antimicrobia.l substances contained in certain Egyptian folk medicines. Seeds of cumin and caraway and leaves of guava, camphor, mint and tiliso and flowers of several herbaceous plants contained antimicrobial agents. These agents could be extracted from guava and camphor leaves by benzene, chloroform, ethyl ether and ethyl acetate and from cumin and caraway seeds by ethyl ether and alcohol and from the herbaceous flowers and mint leaves by benzene, ethyl ether and alcohol