Effect of biofilmed biofertilizer on rice growth in the native soils of the component microbes

The haphazard application of synthetic chemicals in agriculture has led to loss of beneficial microbial communities leading to deteriorating soil productivity and environmental quality. Application of Plant growth promoting rhizobacteria (PGPRs) is widely tested world over to overcome this problem and increasing productivity in different plant species has been demonstrated. Use of biofilmed biofertilizers (BFBFs) is speculated to be more beneficial than the use of monoculture PGPRs and it has been found that use of in vitro produced BFBFs could reduce the use of recommended chemical fertilizers by about 50% in certain crops which would be of great importance in terms of environmental health and economy. The aim of this study was to test the effect of an in vitro formulated BFBF on the growth and yield of rice in soils from which the component bacterium and fungus of BFBF were isolated. Rice variety BG 357 was grown in pots in a green house, in two paddy soils with different salinity levels from Ampara District in Sri Lanka. Five treatments namely 100% recommended chemical fertilizer, 50% recommended chemical fertilizer, 50% fertilizer with the BFBF, the BFBF alone and the control with no fertilizer or BFBF were applied. Growth and yield parameters were recorded at harvest and analysed statistically. The BFBF did not have any effect on plant growth although it significantly improved the seed germination and seedling vigour index in a germination assay. The less saline soil had a significantly higher shoot growth compared to high saline soil and the root growth was vice versa although the total dry weight did not differ. The filled grain dry weight was higher in the less saline soil although the soil type did not affect the 1000 grain weight or filled grain percentage. The 50% chemical fertilizer applied with BFBF improved the filled grain percentage, filled grain dry weight and 1000 grain weight significantly compared to the 50% chemical fertilizer alone treatment and this effect though not significant at 5% probability level, was higher than the 100% chemical fertilizer application regardless of the soil type. Similar effects have been reported with different plant species including rice and further studies need to be carried out under field conditions

Effect of four bio film formulations on rice seed germination and seedling growth

Biofilms are consortia formed by different microbes of which the members are physically and metabolically interdependent and the consortia harbor properties distinct from those of their single components and thus have various applications including improved agricultural productivity. Beneficial biofilms can be developed in vitro and be used as biofertilizers called biofilmedbiofertilizers (BFBFs).Objective of this study was to formulate an effective BFBF formulation for rice. Seven bacterial species isolated from two different paddy soils (coastal and inland) were grown separately in association with a fungus. Four of these two-membered cultures selected as potential biofilm formulations based on forming intimate association, plant growth substance production and Nrfixing ability were tested for the impact on rice seed germination and seedling growth. The percentage seed germination and seedling vigour index of seeds treated with the above four biofilm formulations were significantly higher than the control indicating the potential of these formulations to be used as biofertilisers for rice and thus will be further tested

Effect of a non-native bio filmed bio fertilizer for rice in the Eastern Province of Sri Lanka

Rice is the staple food crop of Sri Lanka and the eastern province alone contributes to more than 21% of the total production of the country. Excessive amounts of chemical fertilizers are used to obtain a higher yield which has been noted to contribute to deteriorate soil microbial community. This leads to poor quality soil resulting in poor crop growth. Use of microbial biofertilizers for rice has gained momentum as a measure of replenishing the depleted soil microbiome, and to restore the beneficial processes. Amongst microbial biofertilizers, biofilmed biofertilizers (BFBFs) have been found to act as microbial ameliorators in deteriorated soil, contributing to better plant growth and higher yield. A field trial using a BFBF (comprising of non-native microorganisms) and rice variety BG 357 was conducted in 2011 Yala season (May — August) at Sammanthurai Agriculture Research Station to assess the potential of the BFBF for rice in the Eastern province. The use of BFBF increased seed germination by ca. 16% (P<0.005) and heading by 8.34%. However, there was no observable effect on yield although the same BFBF showed significant plant growth promoting effect and yield potential at the field trials conducted at Rice Research and Development Institute, Batalagoda (the location of the strains of the BFBF) in 2010 Yala season. Poor plant growth and no heading in BFBF alone indicate the poor competitive ability of the strains of BFBF which are non-native to the region. A BFBF developed from strains native to the region may be effective. Further research is needed in this regar

An assessment of electrochemical chloride extraction as a remediation technique for steel reinforced concrete

Steel reinforced concrete blocks were subjected to chloride extraction after they were dosed with either NaCl or CaCl2. All the blocks were then exposed to the elements at the BRE exposure site for a total period of about 6 years. The steel reinforcement was regularly monitored electrochemically to determine its level of corrosion. Core samples were also analysed before and after treatment to determine the chloride concentration profiles. A selection of blocks were cut into smaller steel-containing prisms after 4 ½ years of exposure and were exposed to controlled laboratory conditions for 6 months while determining the level of corrosion electrochemically. At termination, each steel bar was removed and examined visually. The total weight loss was assessed gravimetrically. The final chloride concentration profile of each prism was also determined. Results suggested that corrosion was reduced significantly following chloride extraction but that the primary long-term controlling factor, both for the desalinated and control specimens, appeared to be the level of chloride present at the depth of the steel reinforcement. As, under normal procedures, a proportion of chloride remains after chloride extraction, a significant level of corrosion of the reinforcement, although greatly reduced, is still likely

The long-term effectiveness of electrochemical chloride extraction as remediation for corroding steel in reinforced concrete

Steel reinforced concrete blocks were subjected to electrochemical chloride extraction after they were dosed with chlorides. Following treatment, the blocks were exposed to the elements at the BRE exposure site for a period of up to 6 years. A selection of blocks were cut into smaller steel-containing prisms after 4 ½ years of exposure and were exposed to controlled laboratory conditions for 6 months while determining the level of corrosion by linear polarisation. At termination, each steel bar was removed and examined visually. The level of corrosion of each bar was also assessed gravimetrically. The final chloride concentration profile of each prism to a depth beyond the steel bars was also determined. Results suggested that corrosion was reduced significantly following chloride extraction but that the primary controlling factor, both for the desalinated and control specimens, was the level of chloride present at the depth of the steel reinforcement. Coating the concrete after treatment resulted in an overall increase in corrosion level, possibly because the coatings were not coherent and allowed moisture to penetrate the concrete through cracks and defects which could not subsequently escape owing to the coating

Induction of MAP Kinase Homologues during Growth and Morphogenetic Development of Karnal Bunt (Tilletia indica) under the Influence of Host Factor(s) from Wheat Spikes

Signaling pathways that activate different mitogen-activated protein kinases (MAPKs) in response to certain environmental conditions, play important role in mating type switching (Fus3) and pathogenicity (Pmk1) in many fungi. In order to determine the roles of such regulatory genes in Tilletia indica, the causal pathogen of Karnal bunt (KB) of wheat, semi-quantitative and quantitative RT-PCR was carried out to isolate and determine the expression of MAP kinase homologues during fungal growth and development under in vitro culture. Maximum expression of TiFus3 and TiPmk1 genes were observed at 14th and 21st days of culture and decreased thereafter. To investigate whether the fungus alters the expression levels of same kinases upon interaction with plants, cultures were treated with 1% of host factors (extracted from S-2 stage of wheat spikes). Such treatment induced the expression of MAPks in time dependent manner compared to the absence of host factors. These results suggest that host factor(s) provide certain signal(s) which activate TiFus3 and TiPmk1 during morphogenetic development of T. indica. The results also provides a clue about the role of host factors in enhancing the disease potential due to induction of MAP kinases involved in fungal development and pathogenecity

Biochemical expression of exudes of a fungal-bacterial bio film during growth and maturation

Biofilms are often complex communities of multiple microbial species and remain attached to surfaces. Fungal-bacterial biofllms are formed when the fungal surface is colonized by one or more species of bacteria. These biofilms can enhance microbial effectiveness compared to the monocultures. Beneficial biofilms can be developed in vitro and be used for various agricultural and biotechnological purposes. As a recent development in biofertilizer research, fungal-rhizobial biofilms have been developed and these are termed biofilmed biofertilizers (BFBFs). This research was focused to investigate chemical composition of compounds exuded during growth and maturation of the biofilms. A developed fungal-bacterial biofilm using an Azotobacter species and a Colletorichum fungal species was used for the study. Exudates of the biofilm, fungal monoculture and bacterial monoculture in solid and liquid states were extracted separately by using three organic solvents; hexane, ethyl acetate and methanol. Extraction was done weekly for four weeks during growth and maturation of the biofllm. Then extracted exudates dissolved in organic solvents were evaporated by using a vortex evaporator. Thereafter crude was mixed with potassium bromide (KBr) and pellets were made. The KBr pellets were analyzed using Fourier Transform Infrared (FTIR) spectroscopy. To evaluate the effect of the exudates of the fungal-bacterial biofilm on seed germination and plant growth in comparison to bacterial and fungal monocultures, a plant assay was done weekly by using lettuce (Lactuca sativa) seeds (N 48). During all four harvests, the fungal-bacterial biofllm produced more diverse functional groups than the mono cultures. The developed biofilm produced carboxylic acids and carboxylic salts, which are associated with plant growth promoting hormones, especially in first and second harvests. Significantly higher plant height and high germination of lettuce with the biofilm exudates could be attributed to above fact. During third and fourth weeks, the biofllm produced more amines and amides than fungal and bacterial mono cultures. This may have contributed to increased pH in biofilm cultures compared to the mono cultures. Thus, it can be concluded that biochemical expression of exudates of fungal-bacterial biofilms during their growth and maturation is very useful for breaking dormancy of seeds and their germination and growth, contributing to high plant productivit

Corticosteroid-induced remission and mycophenolate maintenance therapy in granulomatous lymphocytic interstitial lung disease: long-term, longitudinal change in lung function in a single-centre cohort

AIM: The aim of the study was to evaluate the response in lung function to different treatment regimens for common variable immunodeficiency patients with granulomatous lymphocytic interstitial lung disease (GLILD). METHOD: A longitudinal retrospective cohort study was carried out. Patients were divided into three groups. To assess the response to different treatments, we compared baseline lung function with post-treatment tests. RESULTS: 14 patients with GLILD were included, seven of whom were treated with acute corticosteroids for a mean duration of 132±65 days. Spirometry results were unchanged, but there was a significant improvement in diffusing capacity of the lung for carbon monoxide (DLCO)% and transfer coefficient of the lung for carbon monoxide (KCO)% (median change in DLCO%=7%, p=0.04, and KCO%=13%, p=0.02). Relapse occurred in three out of seven patients. Five patients were treated with long-term mycophenolate mofetil (MMF) with/without corticosteroids for a mean duration of 1277±917 days. No changes were found in spirometry; however, there was a significant increase in DLCO% and KCO% (median change in each of DLCO% and KCO%=10%, p=0.04). Four patients on steroids with MMF successfully weaned the prednisone dose over 12 months. Four patients never received immunosuppression therapy. A significant decline was found in their lung function assessed over 7.5 years. The median reduction in the forced vital capacity (FVC)%, forced expiratory volume in 1 s (FEV1)% and DLCO% was 15%, 7% and 15%, equivalent to 2%, 1% and 2% per year, respectively. CONCLUSION: Corticosteroids improve gas transfer in GLILD, but patients often relapse. The use of MMF was associated with long-term effectiveness in GLILD and permits weaning of corticosteroids. A delay in initiating and continuing maintenance treatment could lead to disease progression

DISTRIBUTION OF Zanthium indicum AROUND GIRITALE TANK

The area around Giritale tank is the main grazing ground of wild and domestic animalswithin the naturc reserve and thcre has been an increase in the population of Xanthiuntitulicurn (Agada) in this area. In the Flora of Ceylon Trimen recorded this as a rare plantprohably introduced from India. Today, it is reported to be present in more than 7 districtsof the country, mostly in moist areas periodically inundated. It reduces the grazingcapacity and the hooked involucres are reported to cause damage to the internal organs ofthe grazers. Studies are heing carried out to find the distribution and suitable controlmeasures.Area around the tank was sampled at 100m intervals. The plant is capable of producingflowers and fruits irrespective of the time of the year and the size of the plant. When lessthan .'i()(Yr; of the area was covered hy the plant the abundance was taken, as low and whcnit was more than .'i0%, as high. .'i3% of the total area has been identified as highabundance and only 9% as freeThe species has already spread from the edge of water towards the forest. Although thefruits are found, the plant has not established in the forest. Soil moisture, texture and thelight intensity determine the growth of this plant. Fruits get embedded in the mud andalter decomposition two achenes arc released which germinate later. There are reports ofXcmtliitun sp. producing two types of achencs, germinating in consecutive years. Studiesarc heing carried out to investigate this.To improve the grazing capacity of the area it is necessary to control the growth of thisplant. Controlled hurning seems to he the best. Ten other species have heen recordedgrowing with Agada. Crotalaria pallida competes with X. lndicum. reducing itspopulation. The possibility of use of Cuscuta chinensis in the control of Xanthiumindicum is being tested.