Effect of Cropping Pattern and Fertilizer Dose Applied in Raised-Bed on The Growth and Yield of Rice (Oryza sativa L.) in Sunken-Bed of The Surjan Rice Field

Irrigation with microcystins-contaminated water threatens growth and yield of crops and human health. Growth of rice at booting stage is crucial for the yield of rice at mature stage. Hence, we studied growth, yield and grains quality of rice as well as accumulation of microcystins in different tissues of rice at booting stage exposed to 1, 100, 1000, and 3000 μg L−1 microcystins solution and then recovered (without microcystins). After a 7-day exposure, microcystins content in tissues was positively correlated with microcystins concentrations, and microcystins content in roots was the highest. In addition, microcystins content in grains of rice treated with 1, 100, 1000 and 3000 μg L−1 microcystins was 4.9, 7.1, 12.6 and 21.2 μg kg−1 dry weight, indicating that the microcystins in grains of rice treated with microcystins (≥1000 μg L−1) could pose a threat to human health through food chain. Low concentration microcystins (1 μg L−1) did not affect growth and photosynthesis, but high concentration microcystins (≥100 μg L−1) inhibited growth and photosynthesis. After a 7-day restoration, growth and photosynthesis in rice treated with microcystins (≥1000 μg L−1) were even worse than those during the exposure period. After maturity, yield of rice as well as protein and amylose content in grains of rice treated with microcystins (≥100 μg L−1) were all lower than those of the control. Our results imply that irrigation with microcystins-contaminated water must be monitored and controlled to avoid harmful accumulation of microcystins and damage to crops yield.

Salt stress exerts a notable influence on rice’s normal growth and development process. It causes a decline in rice yield, and in certain extreme cases can lead to the complete failure of rice crops. Abscisic acid, also known as S-ABA, may play an important role in regulating rice plant responses to various stressors and promoting crop growth against adversity. In this research, the impact of externally applied S-ABA (0.03% S-ABA, diluted 100 times) on the growth and yield of rice was explored. The experiment made use of the traditional rice variety Huanghuazhan as the test material. The study focused on how S-ABA affected rice at various growth phases under salt-stress conditions. The effects of S-ABA sprayed once (three-leaf/one-heart stage) and twice (three-leaf/one-heart stage, break stage) on the photosynthetic characteristics, antioxidant metabolism, membrane lipid peroxidation products, osmotic regulation, and yield of rice under 0.4% NaCl were studied. The experimental outcomes indicated that the presence of salt stress had a restraining effect on the growth of rice. There was a notable decline in the net photosynthetic rate; moreover, the yield was diminished by 26.90%. Salt-induced stress clearly imposed negative impacts on these aspects of rice’s physiological functions and productivity. The exogenous application of S-ABA was highly effective in mitigating the inhibitory influence of salt stress on the growth of rice. When S-ABA was sprayed on two occasions, there was a notable increase in the total chlorophyll content within the rice leaves, ranging from 7.40% to 80.99%. This led to an enhancement in the photosynthetic ability of the plants. Additionally, the growth of rice seedlings was significantly promoted. The activity of antioxidant enzymes also witnessed an upward trend, and the content of soluble protein increased by 0.87–2.60%. The content of malondialdehyde and hydrogen peroxide were decreased by 4.18–12.49% and 13.71–52.18%, respectively, the damage to membrane lipid peroxidation was alleviated, and rice yield was increased by 14.84% and 29.29% after spraying S-ABA once or twice under salt stress, respectively. In conclusion, salt stress inhibits the growth and development of rice during grouting and destroys the antioxidant system of the rice plant, thus reducing its yield. Leaf spraying with S-ABA can alleviate the degradation of chlorophyll, enhance the photosynthesis, antioxidant system, and osmotic regulation ability of rice, reduce salt-stress damage, and thus alleviate the yield loss under salt stress to a certain extent. In addition, the regulation effect of two sprayings of S-ABA is better than that of one spraying. The results of this study revealed the physiological regulation mechanism of S-ABA at different growth stages of rice under salt stress, and provided theoretical support for the reduction of salt-stress damage to rice. This suggests that S-ABA has potential applications in the improvement of salt tolerance in rice.

To reveal the effect of biochar addition on rice growth and yield under water-saving irrigation, a 2-year field experiment was carried out to clarify the variations of rice tiller number, plant height, yield components, and irrigation water use efficiency with different biochar application amounts (0, 20, 40 t/ha) and irrigation management (flooding irrigation and water-saving irrigation). The results showed that the rice yield with biochar addition (20 and 40 t/ha) was 15.53% and 24.43% higher than that of non-biochar addition paddy fields under water-saving irrigation. The addition of biochar promoted the growth of tillers and plant height, improved the filled grain number, productive panicle number, and seed setting rate, thus affecting rice yield. Rice yield was raised with the increase in the biochar application amount. Under the condition of water-saving irrigation, water deficit had a certain negative effect on the rice growth indexes, resulting in a slight decrease in yield. However, irrigation water input was significantly decreased with water-saving irrigation compare to flooding irrigation. Under the comprehensive effect of water-saving irrigation and biochar application, the irrigation water use efficiency of a rice paddy field with high biochar application (40 t/ha) under water-saving irrigation was the highest, with an average increase of 91.05% compared to a paddy field with flooding irrigation. Therefore, the application of biochar in paddy fields with water-saving irrigation can substantially save irrigation water input, stably increase rice yield, and ultimately improve irrigation water productive efficiency.

Rice was grown in an open-field Gangetic soil condition with arsenic amended irrigation water in experimental plot at Institute of Environmental Science of Rajshahi University to see the effect of arsenic (As) on growth and yield of rice (Oryza sativa L.). A popular aman rice variety named BR-11 was cultivated with arsenic amended irrigation water (0 mg, 0.1 mg, 0.5 mg, 1.0 mg, 2.0 mg and 4.0 mg/L As containing water) in a green house made of transparent poly-ethylene paper. Sodium arsenate (Na2HAsO4) was added to irrigation water for arsenic source. The tillers number, panicle length and grain yield of BR-11 rice were found to decrease significantly (p?0.05) with increase of arsenic (As) concentration in irrigation water. The highest values of plant height and straw yield was observed in 0.5 mgL-1 treatment, whereas highest tillers number, panicles number, panicle length and grain yield were found in control treatment. The lowest values of these parameters were observed in the treatment of 4.0 mgL-1 As containing irrigation water. Rice was grown in an open-field Gangetic soil condition with arsenic amended irrigation water in experimental plot at Institute of Environmental Science of Rajshahi University to see the effect of arsenic (As) on growth and yield of rice (Oryza sativa L.). A popular aman rice variety named BR-11 was cultivated with arsenic amended irrigation water (0 mg, 0.1 mg, 0.5 mg, 1.0 mg, 2.0 mg and 4.0 mg/L As containing water) in a green house made of transparent poly-ethylene paper. Sodium arsenate (Na2HAsO4) was added to irrigation water for arsenic source. The tillers number, panicle length and grain yield of BR-11 rice were found to decrease significantly (p?0.05) with increase of arsenic (As) concentration in irrigation water. The highest values of plant height and straw yield was observed in 0.5 mgL-1 treatment, whereas highest tillers number, panicles number, panicle length and grain yield were found in control treatment. The lowest values of these parameters were observed in the treatment of 4.0 mgL-1 As containing irrigation water.DOI: http://dx.doi.org/10.3329/jesnr.v5i1.11553J. Environ. Sci. & Natural Resources, 5(1): 55-59, 2012

The effects of winter weeds on the growth and yield of direct-seeded rice (Oryza sativa L. cv. Akebono) were evaluated in a no-tillage dry paddy field where Alopecurus aequalis Sobol. var. amurensis (Komar.) Ohwi was uniformly dominant, in Kurashiki, Okayama, Japan, in 1994 and 1995. Winter weeds significantly inhibited the growth and spikelet production of rice plants as compared to those in the control plots, which were established by herbicide application. The reduction in the spikelet number finally resulted in a 12.6 to 15.6% yield reduction, although the percentage of ripened grains of rice increased somewhat because of the inhibition of the spikelet number by winter weeds. Rice yields in the weedy and control plots increased in different ways according to the increase in straw weight. The number of spikelets on the rice plants in the control plots increased as straw weight increased. In contrast, the percentage of ripened grain on the rice plants in weedy plots increased as straw weight increased. A higher rate of fertilizer greatly recovered the growth and yield of rice in weedy plots. This result suggests that the basal dressing of fertilizer at a higher volume would reduce the frequency of herbicide application for winter weeds.

Nitrogen fertilizers have a significant impact on the growth of rice. The overuse and inappropriate application of nitrogen fertilizers have resulted in environmental pollution, in addition to subjecting both humans and livestock to negative health hazards. Finding a viable substitute for traditional nitrogen fertilizers is crucial and essential to help improve crop yield and minimize environmental damage. Nano-nitrogen fertilizers offer a possible alternative to traditional fertilizers due to a slow/controlled release of nitrogen. The present work aimed to study the effect of a slow-release urea nanofertilizer on soil ammonical (NH4-N) and nitrate-N (NO3-N) content, culturable soil microflora, and soil enzyme activities in three different soil samples procured from Ludhiana and Patiala districts through a soil column study. Seven treatments, including 0, 50 (75 kg/ha N), 75 (112.5 kg/ha N), and 100% (150 kg/ha N) of the recommended dose (RD) of conventional urea and nano-urea fertilizer were applied. The leachate samples collected from nano-urea treatment exhibited NH4-N for the first two weeks, followed by NO3-N appearance. The higher NH4-N and NO3-N contents in the leachate were recorded for light-textured soil as compared to medium- and heavy-textured soil samples. The soil microbial counts and enzyme activities were recorded to be maximum in light-textured soils. Therefore, this slow-release formulation could be more useful for light-textured soils to decrease applied N-fertilizer losses, as well as for improving the soil microbial viable cell counts and soil enzyme activities. The effect of urea nanofertilizer on the growth and yield of direct-seeded rice (Oryza sativa L.) was also evaluated under field conditions. Both studies were performed independently. Numerically, the highest shoot height, fresh and dry shoot weight, and significantly maximum total chlorophyll, carotenoid, and anthocyanins were recorded in the T2 (100% RDF through nano-urea) treatment. The yield-attributing traits, including the number of filled grains and thousand-grain weight, were also recorded to have increased in T2 treatment. A numerical increase in NPK for plant and grain of rice at 100% RDN through nano-urea was recorded. The soil application of the product exhibited no negative effect on the soil microbial viable cell count on different doses of nano-urea fertilizer. The soil nitrogen fixer viable counts were rather improved in nano-urea treatments. The results reflect that nano-urea fertilizer could be considered as a possible alternative to conventional fertilizer.

Effect of inter-tillage weeding on rice yield, rice growth, and nutrient dynamics without agrochemical and fertilizer application: Results of a three-year study

The field trial was carried out to study the effect of different fertilizer levels and bio-stimulants on growth and yield of rice (Oryza sativa L.) under lateritic soils of Konkan at the Instructional Farm, Department of Agronomy, College of Agriculture, Dapoli during Kharif 2022. The experiment was laid out in strip plot design with 15 treatment combinations replicated thrice. The treatments consist of three horizontal strips of fertilizer levels viz., 80% RDF (F1), 100% RDF (F2), 120% RDF (F3) and five vertical strips of bio-stimulants viz., 0.5% humic acid (B1), 0.5% chitosan (B2), 3% vermiwash (B3), 1% Konkan kalp (B4), 0.1% triacontanol (B5). Results revealed that the application of 120% RDF significantly increased the growth, yield attributes and yield of rice which was superior over rest of the treatments. Among the bio-stimulants, foliar application of 0.5% humic acid recorded significantly higher values of growth, yield attributes and yield of rice and it remained at par with the treatment 0.5% chitosan. Interaction of 120% RDF along with foliar sprays of 0.5% humic acid recorded significantly higher grain and straw yield over rest of the treatment combinations.

In rice-shrimp farming systems, the high level of sodium that shrimps are able to grow in may create an adverse environment for rice. This research aimed to isolate purple nonsulfur bacteria (PNSB) from rice-shrimp fields and select strains that were resistant to H+, Al3+, Fe2+ and Mn2+, that can produce plant growth promoting substances such as 5-aminolevulinic acid, exopolymeric substances, indole-3-acetic acid and siderophores. The selected bacteria were applied in a soil pot experiment to determine their ability to enhance rice growth and yield. From 63 PNSB isolated from 21 paddy fields of rice-shrimp systems, four strains were selected for their properties as biofertilizers and plant growth promoters (PGP). They were all identified as strains of Luteovulum sphaeroides. A randomized complete block design incorporating six treatments was used to investigate the ability of the four PNSB strains to ameliorate rice growth and yield in saline acidic soil with saline water irrigation at 4‰. PNSB cultures at 1.90 × 105 CFU g−1 dry soil weight were applied three times, along with normal chemical fertilizers, and all monitored parameters of rice growth and grain yield significantly improved in soil with a toxic Al3+ content of 10.8 meq 100 g−1. A mixed four cultures most effectively increased grain yield (86.8%) compared with no applied PNSB. Remediation of the pot soil was exhibited in decreased exchangeable Na in soil and proline content in leaves. The four PNSB could act as biofertilizers, PGP and bioremediators with potential to enhance rice yield in rice-shrimp systems for sustainable rice cultivation.

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

Effect of arsenic on photosynthesis, growth and yield of five widely cultivated rice (Oryza sativa L.) varieties in Bangladesh

For paddy rice (Oryza sativa L.), water temperature (Tw) is a major determinant of growth and yield. In rice paddies, Tw is higher than the air temperature (Ta), and this difference significantly affects production, especially in cool climates. However, there is no model to evaluate the effects of Tw on rice yield. To simulate temporal and regional differences in rice productivity under such climates, we developed a simple mechanistic growth model that accounts for the effects of Tw based on the results of previous field trials. The rate of crop ontogenetic change was linearly related with Tw before the heading stage. Leaf area was expressed as a function of leaf emergence and tillering, and leaf senescence was expressed as function of ontogenetic change and spikelet fertility. Radiation use efficiency was less affected by Tw than by leaf area, and its change with respect to ontogenetic changes was expressed using nonlinear functions. Spikelet fertility, which strongly determines grain yield, was expressed as function of cumulative cooling degree‐days (below a threshold temperature), water depth, and the height of developing panicles. This model covered the major processes that are affected by Tw, and can be used for evaluating the role of Tw on rice growth and yield under a cool climate.

Recently, replacing chemical fertilizers with straw returning and new fertilizers has received considerable attention in the agricultural sector, as it is believed to increase rice yield and improve soil properties. However, less is known about rice growth and soil properties in paddy fields with the addition of different fertilizers. Thus, in this paper, we investigated the effects of different fertilizer treatments, including no fertilization (CK), optimized fertilization based on the medium yield recommended fertilizer amount (OF), 4.50 Mg ha−1 straw returning with chemical fertilizers (SF), 0.59 Mg ha−1 slow-release fertilizer with chemical fertilizers (SRF), and 0.60 Mg ha−1 water-soluble fertilizer with chemical fertilizers (WSF), on rice growth, yield, and soil properties through a field experiment. The results show that compared with the OF treatment, the new SF, SRF, and WSF treatments increased plant height, main root length, tiller number, leaf area index, chlorophyll content, and aboveground dry weight. The SF, SRF, and WSF treatments improved rice grain yield by 30.65–32.51% and 0.24–1.66% compared to the CK and OF treatments, respectively. The SRF treatment increased nitrogen (N) and phosphorus (P) uptake by 18.78% and 28.68%, the harvest indexes of N and P by 1.75% and 0.59%, and the partial productivity of N and P by 2.64% and 2.63%, respectively, compared with the OF treatment. However, fertilization did not significantly affect the average yield, harvest indexes of N and P, and partial productivity of N and P. The contents of TN, AN, SOM, TP, AP, and AK across all the treatments decreased significantly with increasing soil depth, while soil pH increased with soil depth. The SF treatment could more effectively increase soil pH and NH4+-N content compared to the SRF and WSF treatments, while the SRF treatment could greatly enhance other soil nutrients and enzyme activities compared to the SF and WSF treatments. A correlation analysis showed that rice yield was significantly positively associated with tiller number, leaf area index, chlorophyll, soil NO3−-N, NH4+-N, SOM, TP, AK, and soil enzyme activity. The experimental results indicate that SRF was the best fertilization method to improve rice growth and yield and enhance soil properties, followed by the SF, WSF, and OF treatments. Hence, the results provide useful information for better fertilization management in the Chaohu Lake region of China.

Research on the effect of dosage of NPK fertilizer on the growth and yield of Paddy Rice (Oryza sativa L.) Using the SRI (Sytem of Rice Intensification) Method in Korong Kapalo Banda, Nagari Aie Tajun District, Padang Pariaman Regency, from January to April 2021. This study aims to obtain the best dose of NPK fertilizer to support the growth and yield of lowland rice using the sri method. This study used a randomized block design (RAK)with 5 treatments and 4 groups in the form of a plot. The data for each observation obtained were analyzed by means of variance, and continued with Duncan’s New Mutiple Range Test( DNMRT) further test at the 5% level. From the experiments that have been carried out, several conclusions can be drawn: the application of N, P, K fertilizer with the SRI method has a very significantly different effect the prameters of plants height, average grain number of panicles, 1000 seed grain weight, and grain weight yield. Per plot bad had no significant effect the percentage of productive tillers. The N4 treatment was the best dose and increased the growth yield of rice plants. It is tecommended to use N4 treatment (200 kg ha-1) on rice plants using the System of Rice Intensification method to get the best.