Halotolerant Phosphat Solubilizing Bacteria from Paddy Saline Soil Halotolerant Phosphat Solubilizing Bacteria from Paddy Saline Soil

Saline and osmotic stress are the main abiotic factors limiting the productivity of rice and other crop plants. Although both coincide in generating water deficit and affect many aspects of plant growth and development similarly, some effects of salinity are distinctively related to the ionic component of salt stress. At the cellular level, dessication tolerance is largely dependent on the cell's ability for osmotic adjustment. Here, we have studied the effects of saline and osmotic stress on endocytosis by rice cells, to investigate the common and distinctive effects of saline-generated stress and osmotically generated stress, and the possible involvement of endocytosis in tolerance mechanisms. For this purpose, we have used rice cell lines with different levels of tolerance and biotinylated bovine serum albumin (bBSA) as an endocytic marker, which in our previous experiments has been shown to enter rice cells by a process with the characteristics of receptor-mediated endocytosis. Our results indicate that the pattern of uptake is common to both types of stress. Thus, when rice cells were subjected to saline or osmotic stress there was an initial dose-dependent inhibition of uptake. However, after more extended stress periods, there was an activation of uptake in the stressed cells. This late activation appears mainly related to the inhibition of growth commonly caused by the different stress agents used in this study. When using cell lines with different degrees of tolerance, the level of uptake activation varied as a function of the type of stress. Thus, under osmotic stress, a higher stress tolerance was directly related to a higher bBSA uptake, while the opposite occurred under saline stress. The possible role of endocytosis in the cellular responses to osmotic and saline stress is discussed.

One of the most common stresses in rice cultivation is salinity. Rice plants stressed by salinity exhibit changes such as yellowing leaves, drying tips, and chlorosis. The efforts made by the government and farmers so far include implementing cultivation scheduling techniques, planting patterns, and using stress-resistant varieties, as well as improving soil to increase water-holding capacity through lime application. Each of these efforts comes with its own risks. Another approach to enhance the growth and yield of rice plants is the application of vitamins. Providing vitamins can stimulate the growth of plant organs, as they play a crucial role in the growth process by acting as catalysts for metabolism. Research has indicated that vitamin B1 can significantly promote plant growth under stressful conditions. This study aims to investigate the positive effects of various concentrations of vitamin B1 on the growth and yield of rice plants while also reducing salinity stress. The method used involved planting three varieties of rice—IR-46, Inpari-32, and Pokkali—in planting buckets using the TABELA system. Vitamin B1 was applied at concentrations of 0, 5, and 10 mM during the peak vegetative phase, with salinity stress of 6 dS/m introduced one day after vitamin application. The plants were maintained under salinity stress conditions until harvest, during which morphological and phytochemical analyses were conducted. Morphological analysis included measurements of plant height, number of tillers, number of productive tillers, number of grains per panicle, and percentage of healthy grains. Biochemical parameters measured included total chlorophyll and electrolyte leakage analysis. The results indicate that vitamin B1 can effectively reduce stress in plants affected by salinity.

Geographical variation in seed germination and biochemical response of milk thistle (Silybum marianum) ecotypes exposed to osmotic and salinity stresses

Two nitrogen-fixing Anabaena strains were found to be differentially tolerant to salinity and osmotic stresses. Anabaena torulosa, a brackish-water, salt-tolerant strain, was relatively osmosensitive. Anabaena sp. strain L-31, a freshwater, salt-sensitive strain, on the other hand, displayed significant osmotolerance. Salinity and osmotic stresses affected nitrogenase activity differently. Nitrogen fixation in both of the strains was severely inhibited by the ionic, but not by the osmotic, component of salinity stress. Such differential sensitivity of diazotrophy to salinity-osmotic stresses was observed irrespective of the inherent tolerance of the two strains to salt-osmotic stress. Exogenously added ammonium conferred significant protection against salinity stress but was ineffective against osmotic stress. Salinity and osmotic stresses also affected stress-induced gene expression differently. Synthesis of several proteins was repressed by salinity stress but not by equivalent or higher osmotic stress. Salinity and osmotic stresses induced many common proteins. In addition, unique salt stress- or osmotic stress-specific proteins were also induced in both strains, indicating differential regulation of protein synthesis by the two stresses. These data show that cyanobacterial sensitivity and responses to salinity and osmotic stresses are distinct, independent phenomena.

Salinity stress adversely affects rice (Oryza sativa L.) growth, development and overall productivity. Multiple strategies have been implemented to enhance the resilience of rice plants, enabling them to grow better in saline environments. Use of biofertilizers, a sustainable alternative to chemical fertilizers, has gained significant attention in modern agriculture due to their potential to improve soil fertility, enhance crop productivity, and mitigate environmental concerns. Biofertilizers encompass a diverse group of microorganisms, including bacteria, fungi, and algae, which interact with plants through various mechanisms. These beneficial microbes have been reported to convert atmospheric nitrogen into plant-available forms and break down insoluble phosphates and zinc complexes in the soil. Additionally, they can also produce growth regulators, enhance nutrient availability, and protect plants against pathogens. In our previous study, a salt-tolerant endophytic fungus isolated from the halophytic wild rice, Oryza coarctata, was identified as Aspergillus welwitschiae Ocstreb1 by whole genome sequence analysis. During the in-vitro experiments, the endophyte showed several plant growth promoting activities such as, zinc and phosphate solubilization, siderophore, IAA, and ACC-deaminase production, nitrogen fixation, etc. in both normal and 900 mM salt stress. In this study, the endophyte was used to formulate a biofertilizer in combination with talcum powder to enhance the growth and yield of rice plants under salinity stress. This research investigated the effectiveness of the biofertilizer in four distinct salinity tanks under both non-saline and 6 dS/m saline conditions, each containing three different varieties of rice. Treatment of BRRI dhan28 (BD-28), BRRI dhan67 (BD-67) and BRRI dhan87 (BD-87) rice plants with the formulated biofertilizer significantly enhanced their yield in both non-saline and saline conditions. Among the three rice varieties, BD-28 showed the highest significant (p<0.05) yield increase, with 104.20% under normal conditions and 3080.56% under salt stress. BD-67 exhibited a 45.15% increase in normal conditions and 153.64% under salt stress (P<0.05). BD-87 showed a significant yield increase only under salt stress, at 293.63% (p<0.05). From the results of the study, it can be proposed that the formulated biofertilizer is a potential eco-friendly and cost-effective solution to improve cultivation and yield of rice in the highly saline coastal regions of Bangladesh. Bioresearch Commu. 10(2): 1474-1481, 2024 (July)

Brown algae is known to produce several phytohormons. Therefore, it could be develop as an important biostimulant for growth of agriculture and horticultural plants. Action of biostimulant depends on optimal time of application. This article report growth and yield of rice plant supplied with liquid extract of several species of brown algae, either during vegetative or generative growth. The treathment influenced variably growth and yield of rice plants. Liquid extract of Sargassum crassifolium and Sargassum polycistum did not influenced growth and yield of rice plants, either supplied in combination with Turbinaria murayana extract or not during generative growth. However, application Sargassum cristaefolium and mixed extract consistenly effected growth and yield of rice plants. Application of Sargassum cristaefolium extract increased shoot dry weight, appoximately 94,70% higher than of control. In contrast, when this plants sprayed with Turbinaria murayana extract during generative growth reduced shoot dry weight, approximately 25% than those sprayed only with Sargassum cristaefolium during vegetative growth. Since the plants supplied with Sargassum cristaefolium during vegetative growth in combination with Turbinaria murayana during generative growth, induced grain weight of rice plants, this suggest that application of Turbinaria murayana extract induced remonbilization of macromolecules such carbohydrate and protein from leave to the grain of rice.Brown algae is known to produce several phytohormons. Therefore, it could be develop as an important biostimulant for growth of agriculture and horticultural plants. Action of biostimulant depends on optimal time of application. This article report growth and yield of rice plant supplied with liquid extract of several species of brown algae, either during vegetative or generative growth. The treathment influenced variably growth and yield of rice plants. Liquid extract of Sargassum crassifolium and Sargassum polycistum did not influenced growth and yield of rice plants, either supplied in combination with Turbinaria murayana extract or not during generative growth. However, application Sargassum cristaefolium and mixed extract consistenly effected growth and yield of rice plants. Application of Sargassum cristaefolium extract increased shoot dry weight, appoximately 94,70% higher than of control. In contrast, when this plants sprayed with Turbinaria murayana extract during generative growth reduced shoot ...

Raising crops for dry and saline lands: Challenges and the way forward.

One of the problems in the paddy field is the lack of availability of nutrient N in paddy soil, it can be overcome by giving azolla and goat manure. The aimis to determine the effect of giving azolla and goat manure for increasing the nutrient N and the growth of rice plants. This research used factorial Random Group Design (RAK) with two treatment factors and three replications. The first factor is azolla dose (0, 7 tons / ha) and the second factor is goat manure dose (0, 5, 10, 15 tons / ha). This research is implemented in the greenhouse of the Faculty of Agriculture, University of North Sumatra, Medan. The result of the study indicated giving of azolla increased C-organic, N-total, N content, and N uptake of plant. Giving goat manure at a dose of 15 tons/ha increased C-organic, number of tillers, canopy dry weight, root dry weight, N content of N uptake. Providing azolla and goat manure 5 tons/ha the highest increased N uptake of plants and growth of lowland rice plants. REFERENCES Abu R.L.A., Z. Basri, U. Made. 2017. Response of Growth and Yield of Rice (Oryza sativa L.). Of Nitrogen Needs Using Leaf Color Bgn. Faculty of Agriculture's Agrotechnology Study Program. Tadulako University. BPS North Sumatra. 2018. Harvested Area and Rice Production in North Sumatra. BPPP. 2006. Organic fertilizers and biological fertilizers. Center for Research and Development of Agricultural Land Resources. West Java. Handayani, M. 2011. Utilization of Goat Manure and Rice Husk Ash to Reduce the Use of Urea and KCl Fertilizers and Their Effects on the Growth of Rice Plants and the Chemical Properties of Paddy Soils. Faculty of Agriculture, University of North Sumatra. Field. Nurmayulis, U. P, F. Dewi, Y. Hasnan, and C. Ania.2011. The Response of Nitrogen and Azolla to Mira I Varieties Rice Plant Growth with SRI Method. Scientific Journal of Isotope and Radiation Applications .ISSN 1907-0322. Rauf, A. W., Syamsuddin., S. R. Sihombing. 2000. Role of NPK Fertilizers in Rice Plants. Agriculture department. Agricultural Research and Development Agency. West Koya Agricultural Technology Study Workshop. Irian Jaya. Setiawati M. R. 2014. Increased N and P Content of Soil and Paddy Rice Results Due to Application of Azolla and Biotertilizer Azotobacter chroococcum and Pseudomonas cepaceae. Faculty of Agriculture. Padjadjaran University. Bandung. Setyorini, D ,. Sri, R, .and Irsal, L. 2010. Agriculture in Wetland Ecosystems in Reversing the Degradation of Land Resources and Water Degradation. Agricultural Research and Development Agency. Ministry of Agriculture. Suharyanto and J. Rinaldi, 2002. Estimation of the Potential and Economic Value of Manure in Bali. Institute for Agricultural Technology Assessment (BPTP), Bali. Sudjana, B ,. 2014. Use of Azolla for Sustainable Agriculture. Singapore University of Krawang. Bandung. Scientific Journal of Solutions 1 (2) 72-81 April-June 2014. Soedharmono, G.G., S.Y. Tyasmoro and H.T., Sebayang. 2016. The effect of giving azolla fertilizer and N fertilizer on rice (Oryza sativa L.) Inpari rice varieties, Faculty of Agriculture, Brawijaya University, East Java. Journal of crop production 4 (2) 145: 152 March 2016. Syamsiah, J., Hendro., B.S., and Mujiyo. 2016. Potential of Azolla as Substitution of Manure on Organk Rice Cultivation. Soil Science Study Program, Faculty of Agriculture, Sebelas Maret University. Surakarta

One of the problems in the paddy field is the lack of availability of nutrient N in paddy soil, it can be overcome by giving azolla and goat manure. The aimis to determine the effect of giving azolla and goat manure for increasing the nutrient N and the growth of rice plants. This research used factorial Random Group Design (RAK) with two treatment factors and three replications. The first factor is azolla dose (0, 7 tons / ha) and the second factor is goat manure dose (0, 5, 10, 15 tons / ha). This research is implemented in the greenhouse of the Faculty of Agriculture, University of North Sumatra, Medan. The result of the study indicated giving of azolla increased C-organic, N-total, N content, and N uptake of plant. Giving goat manure at a dose of 15 tons/ha increased C-organic, number of tillers, canopy dry weight, root dry weight, N content of N uptake. Providing azolla and goat manure 5 tons/ha the highest increased N uptake of plants and growth of lowland rice plants. REFERENCES Abu R.L.A., Z. Basri, U. Made. 2017. Response of Growth and Yield of Rice (Oryza sativa L.). Of Nitrogen Needs Using Leaf Color Bgn. Faculty of Agriculture's Agrotechnology Study Program. Tadulako University. BPS North Sumatra. 2018. Harvested Area and Rice Production in North Sumatra. BPPP. 2006. Organic fertilizers and biological fertilizers. Center for Research and Development of Agricultural Land Resources. West Java. Handayani, M. 2011. Utilization of Goat Manure and Rice Husk Ash to Reduce the Use of Urea and KCl Fertilizers and Their Effects on the Growth of Rice Plants and the Chemical Properties of Paddy Soils. Faculty of Agriculture, University of North Sumatra. Field. Nurmayulis, U. P, F. Dewi, Y. Hasnan, and C. Ania.2011. The Response of Nitrogen and Azolla to Mira I Varieties Rice Plant Growth with SRI Method. Scientific Journal of Isotope and Radiation Applications .ISSN 1907-0322. Rauf, A. W., Syamsuddin., S. R. Sihombing. 2000. Role of NPK Fertilizers in Rice Plants. Agriculture department. Agricultural Research and Development Agency. West Koya Agricultural Technology Study Workshop. Irian Jaya. Setiawati M. R. 2014. Increased N and P Content of Soil and Paddy Rice Results Due to Application of Azolla and Biotertilizer Azotobacter chroococcum and Pseudomonas cepaceae. Faculty of Agriculture. Padjadjaran University. Bandung. Setyorini, D ,. Sri, R, .and Irsal, L. 2010. Agriculture in Wetland Ecosystems in Reversing the Degradation of Land Resources and Water Degradation. Agricultural Research and Development Agency. Ministry of Agriculture. Suharyanto and J. Rinaldi, 2002. Estimation of the Potential and Economic Value of Manure in Bali. Institute for Agricultural Technology Assessment (BPTP), Bali. Sudjana, B ,. 2014. Use of Azolla for Sustainable Agriculture. Singapore University of Krawang. Bandung. Scientific Journal of Solutions 1 (2) 72-81 April-June 2014. Soedharmono, G.G., S.Y. Tyasmoro and H.T., Sebayang. 2016. The effect of giving azolla fertilizer and N fertilizer on rice (Oryza sativa L.) Inpari rice varieties, Faculty of Agriculture, Brawijaya University, East Java. Journal of crop production 4 (2) 145: 152 March 2016. Syamsiah, J., Hendro., B.S., and Mujiyo. 2016. Potential of Azolla as Substitution of Manure on Organk Rice Cultivation. Soil Science Study Program, Faculty of Agriculture, Sebelas Maret University. Surakarta

The effects of submerging paddy fields continuously for one month after transplanting under irrigation water of various depth (and afterwards withdrawing water to keep a shallow irrigation until the end of the season) on the emergence of weeds and the growth and yield of rice plant were experimentally investigated during 1952 to '54 at Konosu Experiment Farm. (1) Weeds - Under 10 or 15 cm. deep submergence, absolute weed quantity, especially relative quantity of weeds resistant to 2, 4-D were found small as compared with those under 3 cm. deep submergence. (2) Rice plant - With 10 or 15 cm. deep water, growth of rice plant was suppressed at the early stage of tillering period, but afterwards it was recovered and became better than that under 3 cm. submergence, showing no decrease in yield. (3) It should be possible to control weeds more effectively by combining deep submergence with spray of herbcides such as 2, 4-D.

Utilization of halotolerant nitrogen biofertilizer can increase N uptake and promote growth and yield of rice plants in saline ecosystem. Halotolerant nitrogen biofertilizer can be applied to seed and seedling in certain dosage. The aim of this study was to obtain the application technique and dosage that can increase N uptake and promote growth and yield of rice plants in saline ecosystem. The research was conducted in the greenhouse in Kawarang District (Indonesia) from September until November 2020. There was used randomized block design which consisted of two factors with three replications. The first factor was application techniques, i.e. seed treatment, nursery treatment, and seed + nursery treatment. The second factor was dosage of halotolerant nitrogen biofertilizer, i.e. 0, 500, 1,000, 1,500 and 2,000 g ha-1. The results showed that halotolerant nitrogen biofertilizer applied in seed and nursery treatment can increase N uptake and plant height by 3.95 g plant-1 and 34.50 cm, respectively. Dosage of 1,500 g ha-1 can increase the total N of soil (0.26%), chlorophyll content (46.97 SPAD), photosynthate accumulation (3.33 g), and rice yield (13.40 t/ha). Application of halotolerant nitrogen biofertilizer in seed and nursery technique at a dosage of 1,500 g ha-1 can be further recommendation in rice cultivation on saline ecosystems.

The experiment was conducted to evaluate the effect of various irrigation methods on the growth and yield of rice plant in direct sowing cultivation. The field experiment involving three irrigation treatments, two levels of nitrogen fertilization and four levels of sowing density was established in 1962. Because of practical consideration in applying irrigation water, the irrigatin treatments were located in separate block. The nitrogen and sowing treatments were randomized in a split plot design with nitrogen levels as the main plot and sowing density as subplot. The replication was three. The irrigation treatments involed three plots of early irrigation, late irrigation and interval irrigation. In the early irrigation plot, the water had been kept 5 cm deep since early tillering stage of rice plant. The late irrigation plot was kept dry during tillering stage of plant, and irrigation was begun when the plant reached young ear formation stage. The interval irrigation plot was applied 5 cm of water in depth at an interval of 7 days. The nitrogen plots were divided into two, that is 0.6 kg and 1.2 kg-N per are. The levels of sowing density were 10, 25, 50 and 100 hills per m2. The results obtained are as follows. 1) The amounts of NH3-N in soil in the plots of both late irrigation and interval irrigation were smaller than that in the plots of early irrigation. The amounts of NO3-N in soil generally were trace, except the case of late irrigation kept dry through the tillering period of plant. It seems that the decrease of available nitrogen in the late irrigation and interval irrigation plots are caused by the leaching of NO3-N and the denitrification resulting from the alternation of oxidation and reduction of soil by irrigation and rainfall. 2) The treatments of late irrigation and interval irrigation indicated the increased activity of root, as measured by means of α-Naptylamine, over the early irrigation. The root activity in the high density (100 hills/m2) was lower than that in low density (10 hills/m2). The root weights per unit area in the late irrigation and interval irrigation plots were lighter than that in the early irrigation plot. The treatment of high density indicated the increased weight of root. 3) The grain yields in the late irrigation and interval irrigation plots were about 10 % less than that in the early irrigation plot, while there was little difference between the former two. The grain and total weight at harvest generally increased as the sowing density increased. The highest yield of all treatments was obtained in the plot with early irrigation, heavy nitrogen fertilization and high sowing density combined. The yield data obtained were fitted with rectangular hyperbola equation of the general form: y=x/a+bx where y is the estimated grain or total weight at harvest in kg per are, x is sowing density, and a and b is a coefficient, respectively. The values of two coefficients in both the late irrigation anb interval irrigation are higher than that in the early irrigation, and heavy dose of nitrogen decreased the values of coefficients. It is therefore concluded that the early irrigation method with heavier nitrogen fertilization and higher sowing density is effective for getting high yield of rice.

In many studies using solution culture or pot culture it was reported that dry matter and yield production of rice plants can be improved by silicon application. There is limited information, however, on field-grown rice. The purpose of this study was to evaluate the effect of the application of Si (in the form of silica gel) on the growth, yield, and canopy structure of rice plants grown under field conditions. The results obtained were as follows: 1) No significant differences in the growth and yield of rice plants with and without Si application were observed under high availability of SiO2. However, the canopy structure of the rice plants was improved by Si application. The distance between the desirable position and the actual position of the top leaf was shorter in the + Si treatment than in the − Si treatment at the maximum tiller number stage. 2) The relative light intensity was higher in the + Si treatment than in the − Si treatment at the maximum tiller number stage, irrespective of the plant height. At the booting stage, the relative light intensity in the upper canopy was lower in the + Si treatment than in the − Si treatment. A higher rate of Si gave a lower light extinction coefficient at the maximum tiller number stage.

Application of Biofertilizer and Azolla (Azolla pinnata) to Improve Several Soil Chemical Properties, Growth and Yield of Rice Plants (Oryza sativa L.). Efforts to increase agricultural production through intensification programs cannot be separated from using artificial chemical fertilizers. However, the continuous use of artificial chemical fertilizers must be balanced by providing organic matter to avoid a deficiency of land-available nutrients, organic matter, and beneficial microorganisms. Using biofertilizers and Azolla can help provide nutrients and improve the biological properties of the soil. This research aimed to determine the effect of the interaction of biofertilizer and Azolla in increasing soil N and lowland rice yields. This research was conducted in a greenhouse, experimental garden, Ciparanje, Jatinangor, Faculty of Agriculture, Universitas Padjadjaran. The experimental design used was a factorial randomized block design with two factors. The first factor, the dose of Azolla pinnata (A), consisted of 4 levels: without Azolla, Azolla 10 t ha-1, Azolla 20 t ha-1, and Azolla 30 t ha-1. In comparison, the second was the dose of solid biofertilizer (H), which consisted of 3 levels, without biofertilizer, 12.5 kg ha-1 biofertilizer, and 25 kg ha-1 biofertilizer, repeated three times. The results of the study showed that there was no interaction between biofertilizer and A. pinata on total soil N, plant N concentration, soil C/N ratio, and lowland rice (Oryza sativa L.) yields; however, the application of Azolla 30 t ha-1 increase the number of productive tillers. The application of biofertilizer and Azolla has yet to increase rice plants' Dry Harvested Grain (DHG). However, the DHG tends to increase by 9.58% and 9.95%, respectively, compared to the control

Agricultural salinization is one of the major and long-lasting abiotic stresses, as it hinders plant growth and development leading to physiological abnormalities that endanger global food security. This is primarily the result of salt build-up in the soil caused by human activities, including irrigation, inadequate growing, and excessive fertilization. Nearly 147 million ha of land are at the risk of soil degradation, with water erosion contributing to 94 million (ha), salinity/alkalinities/acidification for 23 million (50%), water depletion/flooding for 14 million (60%); wind erosion for 9 million and 7 million ha of a combination of factors arising from different forces. In order to ensure food security for the increasing population, the Indian government has set a goal to restore 26 million hectares of degraded land, including those affected by salt, by 2030. It is estimated that almost 10% of the added land becomes saline every year, and by 2050, about 50% of the arable land would be caused by salt. High levels of Na+ and Cl- ions in the soil subdues overall plant growth through ion imbalance, osmotic stress, oxidative stress, reduces nutrient uptake, reduction in yield, and damage to lipids, protein and DNA. In response to salinity stress, plants have developed a range of adaptive mechanisms such as ion homeostasis, osmoprotection, polyamines, nitric oxide, phytohormones and antioxidative defence system. This reviews tells about epigenetic regulation of salinity stress and various mitigation process to combat salinity stress like physical method (leaching, flushing and scrapping), chemical methods (Gypsum, zeolites, biochar, compost, and organic amendments) and biological methods (phytoremidation, bioremediation by use of PGPR, salt-tolerant bacteria, mycorrhiza, cynobacteria, use to various nanoparticle and some biotechnical tools like use of genome wide-association studies, salt-tolerant genes, proteomics, metabolomics and transcriptomics).