Unfilled Grains Research Articles

Enhancing the Photosynthetic and Yield Performance of Rice in Saline Soil by Foliar-Applying Cost-Effective Compounds as Sources of Carbon Dioxide and Potassium

Although rice is highly sensitive to salinity, it is considered one of the best crops to grow in salt-affected mudflat soils to alleviate the salinity problem. Applying chemical compounds for an increase in leaf CO2 and nutrient levels can help mitigate the negative impact of salinity on plants in a cost-effective manner. To identify the benefits of using lithovit (Liv), ethanol (Eth), and potassium carbonate (KC) as a source of CO2 and K to enhance rice production in salt-affected soils, a field study was conducted to assess the effects of these compounds on the agro-physiological parameters of two rice genotypes (Giza178 and Giza179) in saline soils. The compounds were applied as a foliar spray at a concentration of 30 mM each before and after the heading growth stage. The results indicated that the genotype, application time, compounds, and their potential two-way interactions significantly influenced all agro-physiological parameters, with only a few exceptions. The genotype Giza 179 exhibited higher pigment contents, photosynthetic capacity, relative water content (RWC), grain yield, and most yield components compared to Giza 178, with increases ranging from 2.1% to 37.9%. Foliar application of different compounds resulted in a 9.7–37.9% increase in various parameters and a 34.6–43.2% decrease in the number of unfilled grains (NUFG) per panicle compared to untreated treatment. Foliar application of different compounds before heading resulted in an increase in various parameters by 4.8–16.1% and a decrease in the NUFG per panicle by 22.9% compared to those applied after heading. Heatmap clustering analysis revealed that foliar application of Liv before heading was the most effective treatment in enhancing various parameters for both genotypes and mitigating the negative effects of salinity stress on the NUFG. This was followed by Eth and KC before heading for Giza 179. Applying Eth and KC to the leaves after heading had a moderate positive impact on most parameters for Giza 179, outperforming the application after heading for Giza 178. Overall, our findings indicate that spraying readily available compounds that elevate CO2 and K levels in rice leaves can help alleviate the negative impacts of salt stress and improve rice production in salt-affected soils in a cost-effective manner.

The role of Azolla microphylla green fertilizer and N fertilizer application on growth and production of lowland rice (Oryza sativa L.) Ciherang variety for sustainable agriculture

Abstract One effort to maximize Nitrogen nutrient absorption can be done by combining inorganic N fertilizer with Azolla microphylla as green fertilizer. This research aims to identify the effect of applying A. microphylla green fertilizer and N fertilizer on the growth and production of lowland rice variety of Ciherang. The research was done in a greenhouse of Faculty of Agriculture, Universitas Sumatera Utara from November 2023 to February 2024, using a non-factorial Randomized Block Design, namely 100% Azolla; 25% N + 50% Azolla; 25% N + 100% A. microphylla; 50% N + 50% A. microphylla; 50% N + 100% A. microphylla; 75% N + 50% A. microphylla; 75% N + 100% A. microphylla; and 100% N. The research results showed that application of 100% N fertilizer was able to increase plant height by 6-9 week after transplanting (WAT) and the weight of 1000 rice grains. The combination of giving 75% N and 50% A. microphylla tended to increase the weight of unfilled grain per plant 18.87% compared to giving 100% N. It is recommended that fresh A. microphylla be buried in the soil so that it decomposes more quickly.

Unravelling the Current Status of Rice Stripe Mosaic Virus: Its Geographical Spread, Biology, Epidemiology, and Management

Rice stripe mosaic virus (RSMV) belongs to the Cytorhabdovirus species in the Rhabdoviridae family. Recently, RSMV was widely spread in East Asia and caused severe yield losses. RSMV is transmitted by the planthopper vectors, Recilia dorsalis, Nephotettix virescens, and Nilaparvata lugens, that mostly affect rice. The adult vectors can hibernate, transmit the virus, lay eggs on rice plants, and, finally, multiply in subsequent generations, resulting in new infection outbreaks. RSMV-infected rice varieties display striped mosaicism, mild dwarfism, stiff and twisted leaves, delayed heading, short panicles with large unfilled grains, and yield reduction. In nature, the infection of multiple pathogens in the same host is widespread, which is defined as co-infection. It can be antagonistic or synergistic. Pathological synergistic effects between RSMV and other viruses can generate strains with new genetic characteristics, leading to unpredictable epidemiological consequences. After the first identification of RSMV in 2015, significant advancements in understanding the disease’s characteristics, symptoms, cycles, geographic distribution, potential vectors, and synergistic interaction, as well as its management strategies, were developed. To reduce the damage due to RSMV infection, many scientists have recommended pest control techniques to target adult vectors. It is also essential to confirm the actual time of monitoring, development of resistant varieties, and changes in cultivation systems. Due to the limitations of the conventional plant disease control technologies, improvements in efficiency and safety are in high demand. Therefore, to find efficient and environmentally safe controls to mitigate these challenges, reviews of research are the foremost step. In this review, we summarize the basic epidemiological information about the origin of RSMV and its infection symptoms in the field, synergistic interaction with viruses during co-transmission, yield losses, formulation of the disease cycle, and control strategies from several case studies. Finally, we recommend the formulation of the disease cycle and management strategies of RSMV infection.

Studies on Genetic Variability and Heritability in Rice Genotypes (Oryza sativa. L.) under Salinity

Rice (Oryza sativa L.) is one of the most important staple food crops in the world because more than half of the world's population depends on rice for their livelihood. By 2050, the world's rice productivity will need to double in order to keep up with population growth. Narrow genetic base in the released variety has made the improvement in plateaus. In order to go more than the yield barrier, the genetic base must be broadened. Heritability and genetic variability were measured in eighty-six rice genotypes in terms of yield and yield contributing traits under saline soils. Significant differences were found between the genotypes for all of the studied traits according to analysis of variance. High PCV and GCV were recorded for the traits viz., mortality percentage (%), total number of grains per panicle, number of un-filled grains per panicle, sterility percentage (%) and seed yield per plant (g). The traits showed a significant degree of genetic advancement together with high heritability were mortality percentage (%), 1000 grain weight (g) and seed yield per plant (g). Genetic advance over mean were high for mortality percentage (%), number of productive tillers/m2, total number of grains per panicle (g), number of un-filled grains per panicle (g), sterility percentage (%), 1000 grain weight (g) and seed yield per plant (g). This study provides information about the variability and heritability measures which may supplement the breeding program to break the yield plateaus.

Response of Macronutrients, Micronutrient and Biofertilizer on the Growth and Yield Attributes of Kalanamak Rice (Oryza sativa L.) in Central Uttar Pradesh, India

A field experiment was conducted on the combined application of macronutrients and micronutrient along with biofertilizer significantly improved the growth and yield attributes of Kalanamak rice over two kharif seasons, 2022 and 2023. The most effective treatment, T7 [100 per cent RDF (Recommended Dose of Fertilizer) + 25 per cent N through FYM (Farm Yard Manure) + S (Sulphur) @ 40 kg ha-1 + ZnO (Zinc oxide) @ 5 kg ha-1 + BGA (Blue Green Algae) @ 10 kg ha-1] gave maximum increase in growth and yield attributing characteristics viz. plant height (96.80 cm & 97.82 cm), number of tillers hill-1 (11.23 & 11.25), number of effective tillers hill-1 (10.81 & 10.94), panicle length (35.16 cm & 35.43 cm), number of grains panicle-1 (175.82 & 179.45), number of filled grains panicle-1 (159.89 & 161.02), number of unfilled grains panicle-1 (15.93 & 18.43) and test weight (14.9 g & 15 g). This indicates that integrated nutrient management including the integration of organic manures, i.e., FYM, inorganic nutrients (N, P, K, S and Zn) and bio-fertilizers, i.e., BGA enhances rice growth and yield. The positive impact of BGA on nitrogen fixation, combined with the role of Zn and S in grain formation, contributed to higher grain numbers, greater panicle length and increased test weight leading to improved grain yield. Overall, the study highlights the importance of integrated nutrient management, demonstrating that the synergetic use of biofertilizer and balanced fertilization can optimize nutrient availability, improve soil health, reduce unfilled grains and increase crop productivity in Kalanamak rice cultivation.

Parameter genetik padi beras merah (Oryza sativa L.) yang ditanam pada lahan kering dengan sistem gogo

Crossing of F2BC4P19-36 promising line with IPB 3S variety resulted in red rice strains. These strains were selected until obtaining the F5 generation. The research aimed to determine the genetic diversity, heritability values, and genotypic correlation coefficients among quantitative traits for yield of red rice strains in dryland with a continuous cropping system. The study was conducted from May to September 2023 in Tampak Siring Village, Batukliang, Central Lombok Regency, West Nusa Tenggara. It employed a Randomized Complete Block Design (RCBD) with 14 genotypes, replicated three times, totaling 42 treatments. Data analysis was performed using Analysis of Variance (ANOVA) at a 5% significance level. Genetic diversity, assessed broadly, was indicated by traits such as the number of unproductive tillers, number of filled grains, and number of unfilled grains; moderately by traits such as number of productive tillers, total tillers, 100-grain weight, and grain weight per panicle; and narrowly by traits such as plant height, panicle length, flowering duration, and harvesting period. Heritability values were high for yield, moderate for total tillers, number of filled and unfilled grains, 100-grain weight, and flowering duration, and low for traits like plant height, number of productive and unproductive tillers, panicle length, grain weight per panicle, and harvesting period. Genotypic correlation coefficients showed positive associations with yield for traits such as panicle length, grain weight per panicle, and flowering duration, whereas negative correlations were observed with yield for the number of unproductive tillers. Genetic diversity, heritability values, and correlation coefficients serve as determinants for selection criteria

Inhibition of microelement accumulation and disorder of saccharide and amino acid metabolism explain rice grain empty under dimethylarsinic acid stress.

Metabolomic and transcriptomic analyses revealed an intensification of energy metabolism in rice grains under DMA stress, possibly causing the consumption of sugars or non-sugars and the development of unfilled grains Excessive dimethylarsinic acid (DMA) causes rice straighthead disease, a physiological disorder typically with erect panicle due to empty grain at maturity. Although the toxicity of DMA and its uptake and transport in rice are well recognized, the underlying mechanism of unfilled grains remains unclear. Therefore, a pot experiment was conducted using a susceptible variety (Ruanhuayou1179, RHY) and a resistant one (Nanjingxiangzhan, NJXZ) via the metabolomic and transcriptomic approaches to explore the mechanisms of empty grains in diseased rice under DMA stress. The results demonstrate an increase in total and methylated As in grains of RHY and NJXZ under DMA addition, with RHY containing higher levels of DMA. DMA addition increased the soluble sugar content in grains of RHY and NJXZ by 17.1% and 14.3% compared to the control, respectively, but significantly reduced the levels of amino acid, soluble protein, and starch. The decrease of grain Zn and B contents was also observed, and inadequate Zn might be a key factor limiting rice grain yield under DMA stress. Notably, DMA addition altered the expression levels of genes involved in the transport of sugar, amino acids, nitrates/peptides, and mineral ions. In sugar and amino acid metabolism, the reduction of metabolites and the upregulated expression of genes reflect positive regulation at the level of energy metabolism, implying that the reduction of grain starch and proteins might be ascribed to generate sufficient energy to resist the stress. This study provides a useful reference for understanding the molecular mechanism of grain emptying under DMA stress.

Trait analysis of short duration boro rice (Oryza sativa L.) varieties in northern region of Bangladesh: Insights from heatmap, correlation and PCA

The role of genetic variation is utmost importance in the selection of a desirable genotype for breeding programs. In the northern region of Bangladesh, the performance of five short duration boro rice varieties (BRRI dhan28, BRRI dhan74, BRRI dhan81, BRRI dhan88, and Bangabandhu dhan100) on yield and yield-contributing traits were evaluated in four locations. Yield attributes tiller hill-1 (TN), panicle hill-1 (PN), filled grain panicle-1 (FG), panicle length (PL), 1000-grain weight (TGW), and harvest index (HI), showed a positive correlation with grain yield (GY). Conversely, spikelet sterility (SSP) and unfilled grains panicle-1 (UFG) showed negative associations with grain yield. Principal component analysis (PCA) revealed that the first three components accounted for 89.60% of variability. The highest positive eigenvalue was observed in DF, DM, BY, HI, PN, SY, TN, PL and GY in PC1, indicating their significant influence on the overall genotype variations. PC2 was primarily driven by plant height (PH) and FG, while PC3 driven by TGW and UFG. The results suggest that grain yield is highly influenced by FG, PH, DM, DF, PN, TN, PL, TGW, SY, BY, and HI. These components highlighted the importance in distinguishing rice genotypes with higher grain yield potential. By considering these traits, BRRI dhan74 have outperformed other varieties, followed by BRRI dhan88 and Bangabandhu dhan100. BRRI dhan74 is most suitable for all four location followed by BRRI dhan88. The traits such as PN, PL, FG, TGW, PH, & HI significantly influence rice yield and should be prioritized in breeding programs aimed at developing high-yielding rice varieties.

Effect of Drought Periods on Rice Lines Growth and Yield

Numerous variables, such as drought period, growth stage, and varieties, influence rice growth and yield in response to drought. This study was conducted to determine the effect of drought periods on the growth and yields of several rice lines and varieties as well as to select drought-tolerant lines. Using a split-plot design with three replications, the pot experiment was carried out in the greenhouse from December 2015 to April 2016 at the Sukamandi Experimental Site of Indonesian Center for Rice Research (BB Padi). Drought periods were treated as the main-plot, while the rice lines/varieties were treated as sub-plots. The main-plot consists of four levels: control, drought at the maximum tillering stage, drought at the primordia stage, and drought at the grain filling stage. The rice lines used are expand lines of rainfed lowland rice and upland rice from the BB Padi breeding program. The results showed that of the 36 rice lines and 6 varieties tested, drought periods during maximum tillering and primordia affected plant height, while the tiller number was not affected by all drought periods. From the yield characters, drought periods increased unfilled grain percentage and decreased 1000 grains weight and also grain weight per plant. Jatiluhur is consistently tolerant and has the highest yield. There are 8 rice lines with consistent tolerance and not significantly different yields with Jatiluhur: B13650E-TB-80-2, B14168E-MR-6, B14168E-MR-10, B14168E-MR-11, B14168E-MR-12, B14168E-MR-13, B12480D-MR-7-1-1, and B12056F-TB-1-29-1. Keywords: Drought periods, Rice lines, Growth, Yield

Evaluation of Some HYV Boro Rice Varieties for Drought Tolerance Based on Morpho-Biochemical Traits

An experiment was conducted to study the drought tolerance in selected boro rice varieties in pots at the Farm Research Laboratory of Dept. Genetics and Plant Breeding, Bangladesh Agricultural University, Mymensingh in Rabi season of 2014-2015. In this experiment, drought was induced by manipulating the field capacity (30-35% FC as drought, 95-100% FC as control) and moisture content of the soil in the pot. Drought treatment was started 36 days after transplanting and continued till harvest. The work was comprised based on several morphological and biochemical approaches viz. days to 50% flowering, plant height, panicle length, no of total tillers hill-1, no of effective tiller hill-1, days to maturity, no of filled grains panicle-1, no of unfilled grains panicle-1, grain panicle-1, 100 seed weight, grain yield panicle-1, yield hill-1, spikelet fertility, proline and L-ascorbic acid were found to be changed significantly in drought stress as compared to the control. In drought conditions, the highest yield performance was showed in BRRI dhan29 by changing 33.11% compared to its control. Due to drought induction proline accumulation was significantly upregulated by 2.53 and 2.10 folds in BRRI dhan36 and BINA dhan5, respectively and L-ascorbic acid was decreased lowest in BINA dhan10, BRRI dhan50, and BRRI dhan29 by 27.29%, 41.31%, and 43.91%, respectively. This study produced substantial information about the drought tolerance status of the selected boro rice varieties, and therefore, can be an aid for any future attempt to improve the drought tolerance of the studied varieties. Vol. 10, No. 3, December 2023: 247-258

Genetic variation and trait association of fine rice genotypes

To explore high yielding genotype and significant yield contributing trait, field experiment was conducted using alpha lattice design replicated three times at the National Wheat Research Program (NWRP), Bhairahawa, Nepal in 2022. Eighteen fine rice genotypes were evaluated based on nine quantitative traits (Heading days, maturity days, plant height, panicle length, effective tillers, filled grains per panicle, unfilled grains per panicle, thousand grain weight and grain yield per hectare). Variance analysis, correlation and estimation of genetic parameters were conducted to comprehend genetic variations and interrelationships among traits within genotypes. The results showed most of traits except unfilled grains had statistical significance differences. Tarahara-107 (3940 kg/ha) had the highest grain yield followed by Tarahara-2 (3700 kg/ha) and NR 2381-RGA1-RGA2 (3665 kg/ha). Similarly, grain yield showed positive and significant association with filled grains at both phenotypic and genotypic level (rp = 0.7074 ** and rg= 0.9482 **). Elevated values of PCV and GCV were recorded for filled grains (22.05 and 17.57). The high value GAM coupled with high heritability was recorded for filled grains (28.83%), plant height (23.10%), number of effective tillers (21.57%) and thousand grain weight (19.37%). Thus, identified genotypes NR 2380-RGA1-RGA2 and NR 2381-RGA1-RGA2 exhibited early and potential high yielding genotypes while Tarhara-107 and Tarhara-2 identified as high yield, medium maturity and good filled grain number per panicle. In addition, filled grains trait displayed tightly linked with grain yield and possess high GCV, PCV, GAM with moderate heritability indicated direct selection could be employed for trait enhancement in breeding program.

Genetic Variability, Heritability and Genetic Advance in F2 Segregating Population of Cross RNR-15048 x Dokra-Dokri in Rice (Oryza sativa L.)

The present experiment was conducted to study the variability, heritability and genetic advance in F2 segregating population derived from the cross, RNR-15048 x Dokra-Dokri, evaluated in augmented design with two checks at ICAR-IIRR, Hyderabad during the Kharif-2022. Analysis of variance revealed the presence of significant differences for all eleven traits examined, indicating the presence of genetic variation between the individuals studied. Higher values of Genotypic Coefficient of Variation (GCV) and Phenotypic Coefficient of Variation (PCV) were observed for panicle weight, number of filled grains, number of unfilled grains, total grains per panicle, and single plant yield. Least difference was observed between PCV and GCV value for almost all the traits indicating the little influence by the environment and possibility for genetic improvement of these traits through selection. The traits plant height, panicle weight, number of filled grains, number of unfilled grains, total grains per panicle, spikelet fertility, thousand grain weight and single plant yield recorded high heritability (>60%) associated with high genetic advance as percent of mean (>20) resulting in no environmental influence on the expression and selection for improvement of such characters could be worthwhile. High heritability coupled with moderate genetic advance as percent of mean was observed for panicle length propounding non-additive gene action in their inheritance suggesting heterosis breeding could be useful for improving these traits. Overall high PCV and GCV coupled with high heritability and high genetic advance as percent of mean was noticed for panicle weight, number of filled grains, number of unfilled grains, total grains per panicle, and single plant yield suggesting significant amount of variability with predominance of additive type of gene action. Hence, direct phenotypic selection.

Effect of Integrated Use of Poultry Manure with Fertilizer Urea for Sustainable Nitrogen Management in Rice (cv. BRRI Dhan 29) under Two Water Management Systems

The experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh. The experiment's objectives were to evaluate the performance of integrated management of poultry manure with chemical fertilizer urea and to seek water-saving technology that will allow rice (BRRI dhan 29) production to be maintained or increased in the face of declining water availability. The experiment comprised seven treatments viz. T1:100% N from poultry manure, T2:100% N recommended doses of prilled urea, T3:90% N from PU + 10% N from PM, T4:80% N from PU + 20% N from PM, T5: 70% N from PU + 30% N from PM, T6: 60% N from PU + 40% N from PM, T7: 50% N from PU + 50% N from PM. It was laid out in a split-plot design with three replications. The main plots were allocated for irrigation treatments (alternate wetting and dying and continuous flooding) and sub-plots for nitrogen treatments. Altogether, 42 unit plots were conducted, each measuring 2.5mx2.5m. The application of different nitrogen levels significantly influenced all the growth parameters. Irrigation levels significantly affected all the yield and yield contributing characters except plant height, number of ineffective tillers, panicle length, unfilled grain per panicle, 1000 grain weight and harvest index. The highest value of total tiller/hill (11.01), number of effective tillers per hill (9.72), filled grain per panicle (132.23), grain yield (4.80), straw yield (6.68), biological yield (11.47) was observed in the two-irrigation system while height value of non-effective tiller/hill (1.29). The effect of nitrogen treatment was found to be significant. On the other hand, the interaction effect of irrigation management and treatments significantly influenced all the yield parameters except plant height, No. of tiller/ hill, no. of non-effective tiller/hill, panicle length, unfilled grain/panicle and 1000 grain weight. The height value of all those parameters was recorded at the I1×T2 (continuous flooding ×100% N recommended doses of prilled urea). The lowest value of all these parameters was recorded at the I2×T1 (AWDI × 100% N from poultry manure) and I1×T1 (continuous flooding × 100% N from poultry manure). The integrated use of 90% N from PU + 10% N from PM appeared as the better practice because of reducing the considerable amount of prilled urea in Boro rice (cv. BRRI dhan 29) cultivation in terms of grain yield. Moreover, the best promising practice was obtained using 100% N recommended doses of prilled urea applied with continuous flooding (CF).

Size measurement and filled/unfilled detection of rice grains using backlight image processing.

Measurements of rice physical traits, such as length, width, and percentage of filled/unfilled grains, are essential steps of rice breeding. A new approach for measuring the physical traits of rice grains for breeding purposes was presented in this study, utilizing image processing techniques. Backlight photography was used to capture a grayscale image of a group of rice grains, which was then analyzed using a clustering algorithm to differentiate between filled and unfilled grains based on their grayscale values. The impact of backlight intensity on the accuracy of the method was also investigated. The results show that the proposed method has excellent accuracy and high efficiency. The mean absolute percentage error of the method was 0.24% and 1.36% in calculating the total number of grain particles and distinguishing the number of filled grains, respectively. The grain size was also measured with a little margin of error. The mean absolute percentage error of grain length measurement was 1.11%, while the measurement error of grain width was 4.03%. The method was found to be highly accurate, non-destructive, and cost-effective when compared to conventional methods, making it a promising approach for characterizing physical traits for crop breeding.

Acidity and nutrient management practices for enhancing soil nutrient availability, nutrient uptake and grain yield of rice in Vaikom kari soils in Kuttanad, Kerala

A field investigation was conducted during August to December 2015 and 2016 in farmers` fields in Thalayazham panchayat in Kottayam district. The experiment was laid out in randomized block design having 16 treatments in three replications with rice (Oryza sativa L.) var. Uma. The treatments were dolomite, lime + MgSO4 or RHA (rice husk ash) + MgSO4 along with 100% package of practice (POP) alone or with 100% POP + foliar spray of 13-0-45 N-P-K (KNO3) (1%) or borax (0.5%) or 13-0-45 + borax at PI (panicle initiation) stage. Lime + MgSO4 + 75% POP + 13-0-45 + borax as well as lime without MgSO4 + 100% POP combined with 13-0-45 or borax or both were also included as treatments. Higher grain yield of 5.42 and 5.57 t ha-1 during 2015 and 2016 respectively were produced by dolomite + POP + 13-0-45 followed by dolomite + POP + 13-0-45 + borax and lime + POP + MgSO4 + 13-0-45. The treatments involving dolomite and lime with or without MgSO4 produced taller plants, higher tiller number m-2 and higher Leaf Area Index during both the years. Dolomite + POP + 13-0-45 produced the highest number of panicles m-2. Higher test weight and lower percentage of unfilled grains were observed with dolomite + POP + 13-0-45 and dolomite + POP + 13-0-45 + borax. Lime and dolomite treatments were more effective in reducing soil acidity and improving dehydrogenase activity and nutrient availability in the soil than RHA treatments during both the years. However, the effect of liming materials applied as basal and at 30 DAS diminishes after the crop and this necessitates application of liming materials in every crop season. Availability of soil N improved by treatments involving lime + POP without MgSO4 at PI and harvest stages. The treatments involving dolomite + POP and lime + POP with or without MgSO4 recorded higher available P during PI stage. In general, higher status of available K was registered by the treatments involving dolomite or lime application and lower K status registered by the treatment with 75% POP fertilizer. All treatments involving lime or dolomite registered higher soil available Ca and those involving dolomite or lime + MgSO4 showed higher availability of Mg in the soil. The treatments involving dolomite registered lower status of soil available Fe and higher status of available B. Higher status of available Zn was registered by the treatments involving dolomite or lime + MgSO4. Soil pH was significantly and positively correlated with available P, Ca and Mg and significantly and negatively correlated with available Fe in the soil. In general, higher uptake of macronutrients was observed with dolomite or lime + MgSO4 treatments along with 100% POP during both the years. Foliar spray of 13-0-45 recorded higher N and K uptake. Significant and positive correlation of grain yield with uptake of macro nutrients was also observed.

Impact of Climate Resilient Technology on Growth and Yield of Paddy (Oryza sativa L.) under Submergence Condition

The submergence of rice fields is a significant issue in India's rice production, which is further aggravated by the unpredictable monsoon rain patterns and the impact of climate change. Larger variation in rainfall patterns affected by the timing of nursery raising and transplanting later in the main field therefore, we adopted Climate Resilient Technology (CRT) for rice production, Extended seedbed durations for rice seedlings allow for adequate rainfall during the monsoon season. So that the experiment was conducted at 30 farmer’s fields of NICRA village, Khana Bari, Kishanganj, Bihar, India, in 2022 under the supervision farm science Center, Kishanganj, the experiment was framed in randomized block design with ten replications. All plots received the recommended dose of fertilizers (120:60:40 kg ha-1 N.P.K.) in equal amounts. Urea, di-ammonium phosphate, and muriate of potash were used as the sources of nitrogen, phosphorus, and potassium, respectively. To determine the growth characters i.e., plant height (cm) at harvest stage, number of effective tillers hill-1, LAI, Chlorophyll concentration (SPAD) and days to 50 per cent flowering were recorded at 90 days. Yield attributes viz., After the completion of the harvest, various observations were recorded, such as the number of panicles/m2, the number of grains per panicle, the number of filled and unfilled grains per panicle, the test weight in grams, and the yield. This encompassed grain yield, straw yield, biological yield in quintals per hectare, and harvest index percentage. During the field experiment, both the climate-resilient technology Swarna Sub1 and Sabour Sampans paddy varieties were tested. Swarna Sub1 was found to be significantly superior in terms of plant growth, yield attributes, and yield characteristics. under submergence conditions. The significant maximum grain yield (48 q ha-1), straw yield (84 q ha-1), biological yield (153 q ha-1), and harvest index (45%) were recorded in Swarna Sub-1.

Variability and genetic gain prediction for maintainer line improvement of hybrid rice in Bangladesh

Assessment of genetic variability in the nursery of the breeding population is essential for crop improvement successfully. Thirteen (13) maintainer lines of hybrid rice were evaluated to estimate the level of their genetic diversity and heritability of grain yield influencing parameters in the transplanted Aman, 2020 season. The studied traits were days to 50% flowering, total effective tillers plant-1, plant tallness (cm), length of flag leaf (cm), breadth of flag leaf (cm), panicle size (cm), filled grains panicle-1, unfilled grains panicle-1, growth duration (days) and grain yield (tha-1). Coefficient of variation (genotypic and phenotypic) was noticed high for most traits that revealed high variability among the studied genotypes. Broad-sense heritability ( ) was high in all traits except flag leaf breadth. Analysis of the cluster and its mean comparison showed that cluster 2 (i.e. BRRI 11B, BRRI 99B, IR 79125B and IR 79156B) represented the best agronomic traits and yield potentials. Therefore, selection of genotypes with valuable attributes from cluster 2 will be considered for maintainer line improvement programs. The use and estimation of predicted genetic gain will provide a visionary insight of the future genotypes produced after the crossing of the genotypes under study. Bangladesh Rice J. 26 (1): 69-78, 2022

Growth and result performance of 10 promising resistant lines of tungro disease in Lanrang South Sulawesi

Increased rice production is constrained by various limiting factors, One of these is tungro disease, which can limit productivity. When resistant tungro varieties are available, they are regarded as an affective control tool that is also more environmental friendly. Advanced yield experiment represents a phase in the process of producing cultivars that are resistant to tungro disease. The study aimed to determine the growth and result performance of tungro-resistant lines with greater phenotypic characteristics and yield potential compared to other tungro resistant varieties. The study was carried out from July to October 2018 at the Tungro Disease Research Station in Lanrang Sidrap, utilizing a design with a randomized complete block design, It was repeated three times using 10 tungro-resistant lines and two comparative varieties, namely Inpari 7, Lanrang, and Ciherang. The F test was used to examine the data, and the Least Significant Difference (LSD) test was used to determine significance. The parameters observed were Flowering age of 50% (days), number of panicles per m2, plant height (cm), density score, the weight of 1000 grains, number of filled and unfilled grains per panicle, moisture content (%), grain yield (kg/ha). Results revealed that there were four lines BP12280-3f-7-Kn-2-1*B-Lrg-1-1-10-9, BP12280-3f-7-Kn-2-1 * B-Lrg-1- 1-10-9, BP12206f-8-3-2 * B-LR-20-4 and BP12280-3f-7-Kn-2-1 * B-Lrg-1- 16-14 with a higher grain yield than Ciherang and Inpari 7 Lanrang, which benefited by 1000 grain weight, the number of grains filled per panicle and flowering age is 50% earlier than the comparison variety.

Evaluating of abiotic stress tolerance-inducing substances on the growth, physiology and yield of rice (Oryza sativa L.)

Moisture stress due to delayed onset of monsoon, drought or frequent dry spell is one of the major abiotic stresses that affect rice production in Tamil Nadu. It reduces the yield of rice up to 85 % based on its severity. The foliar application of abiotic stress tolerance inducing substances may aid in mitigating stress-induced damages and increase the yield of rice plants. Salicylic acid, ZnSO4, gibberellic acid, humic acid, pink pigment facultative methylotrophs (PPFM), etc. are reported to increase antioxidant enzyme activities and resistance to drought stress however, its effects on crops were location specific. Field experiments were conducted at Annamalai University Experimental Farm, Annamalainagar, Cuddalore District in Cauvery Delta Zone of Tamil Nadu during “Kuruvai” and “Nanvarai” (Kharif and Rabi) seasons of 2021 and 2022 to study the effect of foliar application of stress tolerance inducing substances on the performance of transplanted rice under moisture stress condition. The experiment was laid out in randomized block design (RBD) with 12 treatment combinations including control; Recommended dose fertilizer (RDF) with + acute soil drying + water spray/ KNO3 @ 2% and ZnSO4 @ 0.5% two foliar sprays/ salicylic acid @ 200 ppm/ gibberellic acid @ 40 ppm/ humic acid @ 0.2%/pink pigment facultative methylotrophs (PPFM) @ 2% and was replicated thrice. Among the treatments, application of recommended dose of fertilizer (120 kg N, 40 kg P2O5 and 40 kg K2O/ha) along with KNO3 @ 2% and ZnSO4 @ 0.5% at panicle initiation and 15 days after first spray and humic acid @ 0.2% at booting stage and 15 days after first spray (flowering stage) increased the plant height of 41.01%, dry matter production of 84.70%, leaf area index of 94.25%, number of productive tillers/m of 32.43%, number of filled grains/panicle of 39.14%, reduced unfilled grains /panicle of 368.23%, increased grain yield of 87.23% and straw yield of 82.57% and benefit cost ratio of 1.86.

A Comprehensive Genome-Wide Investigation of the Cytochrome 71 (OsCYP71) Gene Family: Revealing the Impact of Promoter and Gene Variants (Ser33Leu) of OsCYP71P6 on Yield-Related Traits in Indica Rice (Oryza sativa L.).

The cytochrome P450 (CYP450) gene family plays a critical role in plant growth and developmental processes, nutrition, and detoxification of xenobiotics in plants. In the present research, a comprehensive set of 105 OsCYP71 family genes was pinpointed within the genome of indica rice. These genes were categorized into twelve distinct subfamilies, where members within the same subgroup exhibited comparable gene structures and conserved motifs. In addition, 105 OsCYP71 genes were distributed across 11 chromosomes, and 36 pairs of OsCYP71 involved in gene duplication events. Within the promoter region of OsCYP71, there exists an extensive array of cis-elements that are associated with light responsiveness, hormonal regulation, and stress-related signaling. Further, transcriptome profiling revealed that a majority of the genes exhibited responsiveness to hormones and were activated across diverse tissues and developmental stages in rice. The OsCYP71P6 gene is involved in insect resistance, senescence, and yield-related traits in rice. Hence, understanding the association between OsCYP71P6 genetic variants and yield-related traits in rice varieties could provide novel insights for rice improvement. Through the utilization of linear regression models, a total of eight promoters were identified, and a specific gene variant (Ser33Leu) within OsCYP71P6 was found to be linked to spikelet fertility. Additionally, different alleles of the OsCYP71P6 gene identified through in/dels polymorphism in 131 rice varieties were validated for their allelic effects on yield-related traits. Furthermore, the single-plant yield, spikelet number, panicle length, panicle weight, and unfilled grain per panicle for the OsCYP71P6-1 promoter insertion variant were found to contribute 20.19%, 13.65%, 5.637%, 8.79%, and 36.86% more than the deletion variant, respectively. These findings establish a robust groundwork for delving deeper into the functions of OsCYP71-family genes across a range of biological processes. Moreover, these findings provide evidence that allelic variation in the promoter and amino acid substitution of Ser33Leu in the OsCYP71P6 gene could potentially impact traits related to rice yield. Therefore, the identified promoter variants in the OsCYP71P6 gene could be harnessed to amplify rice yields.