M. S. Rahman , M. A. U. Mridha , S. M. N. Islam , S. M. S. Haque , S. K. Shah , P. P. Dhar

Abstract

The ischolar_mains and rhizosphere soils of 14 leguminous forest tree seedlings were assessed at two nurseries in Bangladesh for the study of AM colonization and spore population. A great number of variations were observed in AM colonization in the ischolar_mains and spore populations in the rhizosphere soils. Four genera were isolated and identified from the rhizosphere soils of different host species. The dominat genus was Glomus which was followed by Acaulospora, Entrophospora and Gigaspora. The possible role of indigenous AM fungi has been ensured for the primary establishment of nursery seedlings.

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B. M. Khan , M. A. U. Mridha , M. K. Hossain , S. M. S. Huda

Abstract

Microbial inoculant as effective microorganisms (EM) was used to find out their influences on seedlings growth and development of Albizia procera (Roxb.) Benth. The seedlings were grown in a mixture of forest top soils and cowdung (3 : 1) kept in polybags. The EM solution at different concentrations (0.1, 0.5, 1, 2, 5 and 10%) was incorporated before and after a week of sowing the seeds. Germination as well as physical growth parameters like shoot and ischolar_main length, vigor index, collar diameter, leaf number, fresh and dry weight of shoot and ischolar_main and total biomass increment were measured. The nodulation status influenced by EM was also observed along with the measurement of chemical parameters viz. chlorophyll a, chlorophyll b and carotenoid. Both germination and the measured physical growth parameters were found significantly (P < 0.05) higher in seedlings treated with different concentrations of EM solution in comparison to control. Maximum growth was observed at 2% concentration followed by 5% and 1%. Nodulation was higher at 0.1% concentration of EM but it normally decreased with the increase of concentrations. Leaf pigments were also significantly (P < 0.05) higher in most of the treatments with respect to control. The results of the present study indicate that the EM technology might be useful to improve the growth of seedlings in the nursery. These also indicate that the associated beneficial organisms along with the polybag soils might be of value in improving the degraded soil or poor field soil for better nutrient and water uptake during the initial growth of transplanted seedlings.

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P. P. Dhar , M. A. U. Mridha

Abstract

Roots and rhizosphere soils of eight different tree species (Albizia odoratissima, Artocarpus chaplasha, Elaeocarpus robustus, Mangifera sylvatica, Quercus velutina, Syzygium cumini, Tectona grandis, Toona ciliata were collected from the Aagoonia forest to determine the biodiversity of arbuscular mycorrhizal (AM) colonization and AM fungal spore population. Roots of all the tree species were found colonized by AM fungi. The range of colonization varied significantly (18-83%). The highest was recorded in E. robustus (83%) followed by T. ciliata (72%), Q. velutina (62%), T. grandis (59%) M. sylvatica (50%), S. cumini (45%) and A. odoratissima (33%). The lowest was recorded A. chaplasha (18%). Vesicular colonization was recorded ranging 10-60% in six tree species. The highest was recorded E. robustus (60%) followed by T. ciliata (54%), T. grandis (40%), S. cumini (28%) and Q. velutina (20%). The lowest was A. odoratissima (10%). No vesicular colonization was recorded in A. chaplasha and M. sylvatica. Arbuscular colonization was recorded (4-30%) in six tree species. The highest was recorded T. grandis (30%) followed by Q. velutina (12%) and T. ciliata (10%). The lowest was recorded in S. cumini (4%). Arbuscular mycorrhizal fungal spore population varied significantly (120-784/100g dry soil). The highest population was recorded in the soils of T. ciliata (784) as followed by E. robustus (681), T. grandis (333), Q. velutina (285), M. sylvatica (256), A. chaplasha (210) and A. odoratissima (185).

Keywords

Arbuscular Mycorrhiza, Biodiversity, Colonization, Spore Population

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Rajasree Nandi ¹, M. A. U. Mridha ², Md. Kalimuddin Bhuiyan ¹

Affiliations
1 Institute of Forestry and Environmental Sciences, University of Chittagong, Chittagong 4331, BD
2 King Saud University, Plant Production Department. P.O.Box 2460, Riyadh 11451, SA

Abstract

Status of Arbuscular mycorrhizal (AM) colonization in seven tree species (Albizia saman, Acacia auriculiformis A. Cunn. ex Benth., Albizia lebbeck, Chickrassia tabularis A. Juss., Eucalyptus camaldulensis Dehnn., Gmelina arborea (Roxb) DC and Swietenia macrophylla King.) collected from the hilly areas of Chittagong University (CU) was investigated. Roots and rhizosphere soil samples were collected in different seasons (pre-monsoon, monsoon and post monsoon). Percentage of AM colonization in ischolar_main and number of spores/100gm dry soil were assessed. The result of the investigation reveals that the intensity and percentage of AM colonization varied in different forest tree species in different seasons. Maximum AM colonization and spore population were found in pre-monsoon and minimum were in monsoon season. The intensity of colonization was maximum in C. tabularis (74.43%) in pre-monsoon, A. lebbeck (69.45%) in monsoon and S. macrophylla (67.8%) in post monsoon seasons and minimum in A. auriculiformis (53.75%) during pre-monsoon, A. saman (24.4%) in monsoon and A. saman (19.36%) in post monsoon seasons. The number of AM fungal spores found per 100g dry soil ranged from 164 to 376 during pre-monsoon, 27 to 310 during monsoon and 194 to 299 in post monsoon seasons. Out of six recognized genera of AM fungi, Glomus, Sclerocystis, Entrophospora, Scutellospora, Acaulospora and other unidentified spores were observed.

Keywords

Arbuscular Mycorrhizal Fungi, Colonization, Rhizosphere, Spore Population, Tree Species.

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