Isolation and selection of Bradyrhizobium from the root nodules of indigo plants (Indigofera tinctoria L.)

This research was conducted from 2004 to 2005 to isolate and select Bradyrhizobium from the root nodules of indigo plants (Indigofera tinctoria L.). For isolation of Bradyrhizobium, root nodules were collected from indigo plants. Fourteen Bradyrhizobium isolates were identified depending on colony, morphological and biochemical characteristics. Out of fourteen isolates, six (HSTU-IR2, HSTU-IR3, HSTU-IR4, HSTU-IR9, HSTU-IR10 and HSTU-IR14) were found promising with respect to nodulation, shoots and roots weights and N fixation by the indigo plants grown inside the Leonard Bottle Jar Assembly (LBJA).Key words: Bradyrhizobium, isolation, selection, root nodules, indigo plants

Selection of superior peat-based Bradyrhizobium inoculants for the cultivation of (Indigofera tinctoria L.)

The pot experiment was conducted to the peat-based Bradyrhizobium inoculants as biofertilizer for cultivation of indigo (Indigofera tinctoria L.). Six isolates of Bradyrhizobium of indigo origin (HSTU-IR2, HSTU-IR3, HSTU-IR4, HSTU-IR9, HSTU-IR10 and HSTU-IR14) were collected from the Department of Soil Science, Hajee Mohammad Danesh Science and Technology University (HSTU), Dinajpur, Bangladesh. Peat-based Bradyrhizobium inoculants were prepared with these six isolates and the inoculants were tested for their effects on nodulation, growth and yield of indigo plants through a pot experiment. The results revealed that the isolate HSTU-IR3 recorded the highest number and weight of nodules, more amount of N content in nodules, highest plant shoot and weight. The isolate HSTU-IR4 and HSTU-IR3 produced the tallest plant, largest shoots and roots N content. Based on the overall results two isolates viz. HSTU-IR3 and HSTU-IR4 performed superior to others

Effectiveness of Azorizobial strains isolated from Sesbania rostrata

Isolation and characterization of bacteria were done from the root nodules of African dhaincha (Sesbania rostrata) to study their effects on growth parameters, nodulation and N uptake. Five isolates were obtained from African dhaincha and were identified them as Azorhizobium on the basis of their colony, morphological and biochemical characteristics. A pot experiments were conducted by using 6 treatments, comprising 5 isolates of Azorhizobium and an uninoculated control to evaluate the performance of the isolates. The experiment was laid out in a Completely Randomized Design (CRD) with 3 replications. Azorhizobium inoculation gave statistically higher values for all the parameters viz. plant height, leaf number plant-1, dry weight of nodule, dry matter yield, N content of shoot (%), total N in shoot over uninoculated control (T1). The highest values of all the parameters except stem nodule number plant-1, root nodule weight and N content of shoot were obtained with the treatment T5 (SR-R-4). The total dry matter yield of African dhaincha ranged from 1217 mg plant-1 noted in the uninoculated control (T1) to 5483 mg plant-1 recorded for the treatment T5 (SR-R-4). The total dry matter yields were increased by 138, 219, 273, 351 and 290 % over control (T1) due to T2 (SR-R-1), T3 (SR-R-2), T4 (SR-R-3), T5 (SR-R-4) and T6 (SR-R-5), respectively. Total N uptake by shoot of African dhaincha had been influenced significantly due to different treatments and the corresponding percent increases in total N uptake by shoot were 359, 496, 429, 629, and 490, respectively, due to T2 (SR-R-1), T3 (SR-R-2), T4 (SR-R-3), T5 (SR-R-4) and T6 (SR-R-5).Considering all the growth parameters, nodulation, dry matter yield, N content of shoot and total N uptake by shoot, it may be inferred that the isolate SR-R-4 showed the best performance. The isolates SR-R-5 and SR-R-3 were also found promising. [Fundam Appl Agric 2018; 3(3.000): 537-544

Assessment of the Effects of Selected AM Strain on the Growth and Yield of Brinjal

Arbuscular mycorrhizal (AM) fungi can increase plant uptake of nutrients especially relatively immobile elements such as P, Zn and Cu and consequently, improve plant growth and yield. The study was conducted to identify native AM strains, multiply and test their effects in reduction of P fertilizer brinjal production. Rhizosphere soils and roots of and brinjal were collected from each of four AEZs, viz. AEZ-9 (RARS, Jamalpur), AEZ-11 (RARS, Jashore), AEZ-25 (ARS, Bogura) and AEZ-28 (BARI, Joydebpur) in 2014-2015. Characterization and identification of arbuscular mycorrhizal strains was studied in the microbiology laboratory of Bangladesh Agricultural Research Institute (BARI). Nine AM strains such as Glomus geosporum, G. mosseae, G. fasciculatum, Acaulospora dilatata, A. mellea, A. morrowiae, Entrophospora infrequens, Sclerocystis coremioides and Gigaspora margarita were identified in brinjal. The collected mycorrhizal strains were maintained with trap crop sorghum under net house condition in 2014-2015 onwards. The best performing AM strain (Glomus mosseae) was selected from pot experiments at greenhouse of BARI. The sandy clay loam soil was used as the potting media. Nine each AM strains each from brinjal were tested with corresponding crops. Randomized Complete Block Design (RCBD) was followed with four replications. Dry matter yield (both root and shoot), some vegetative parameter, % root colonization and number of spores were observed. Finally the efficiency of the selected mycorrhiza, Glomus mosseae was tested under field condition during 2016-2017 and 2017-2018. Factorial RCBD was followed for field experiments with eight treatments and four replications. Selected soil-based AM inoculum (Glomus mosseae) that preserved in sorghum culture were used in seedbed of respective crops. Many morphological parameters and yield attributes were found as highest from 75% P. The highest crop yield was found from 75% P+AM, which was statistically similar to 100% P-AM indicating the possibility of saving 25% P in these three crops in AEZ 28 of Bangladesh. It was observed that Glomus mosseae could save 25% P in brinjal cultivation