Rice Culture Research Articles

Evaluation of Pre-Released Rice Cultures at Different Nitrogen Levels

A field experiment was conducted to evaluate the pre-released rice cultures at different nitrogen levels during kharif, 2020-21 at Agricultural Research Station, Bapatla. The experiment was laid-out in split plot design with three replications. The four rice varieties viz, BPT 2776, BPT 2766, BPT 2824 and BPT 2846 were considered as main treatments and four nitrogen levels viz, 80 kg ha-1, 120 kg ha-1, 160 kg ha-1 and 200 kg ha-1were considered as sub treatments. The results revealed that BPT 2846 recorded the highest plant height, productive tillers, panicle length, grain yield (5417 kg ha-1) and straw yield (7073 kg ha-1). The highest nitrogen uptake both in grain and straw also recorded highest values with BPT 2846 pre-released culture. Among the nitrogen levels 200 kg N ha-1 recorded the highest growth, yield attributes, yield and nutrient uptake of pre-released cultures. The data pertaining to economics 160 kg N ha-1 recorded the highest gross returns, net returns and B:C ratio.

First report of Rice panicle blight caused by Fusarium sporotrichioides in China.

Rice (Oryza sativa L.) panicle blight, caused by various fungal and bacterial pathogens, is an emerging threat to rice production, due to the impact on rice yield and quality. In the autumn of 2020, a survey was conducted to understand the etiology of the disease in Liaoning province, an important rice growing area in northeastern China. Rice seeds with typical reddish or brown spots on the glumes were collected from various rice fields. Symptomatic seeds were sterilized with 5% sodium hypochlorite and 75% ethanol, rinsed in sterile distilled water, and placed on potato dextrose agar (PDA) plates. After 3 to 5 days of incubation at 25°C, suspected Fusarium strains showing cream to salmon colonies on PDA were purified by the single-spore isolation method. The identification of these strains were performed based on morphological and molecular characteristics. Fusarium incarnatum-equiseti species complex was the most frequently, followed by the members of Fusarium graminearum species complex and Fusarium fujikuroi species complex. However, one strain was identified as F. sporotrichioides Sherb. based on the following results: (I) Colonies on PDA produced dense mycelia and typical red pigment on the undersurface. Macroconidia were usually 3- to 5-septate, moderately curved to straight, and 27.46 ± 7.16 × 3.78 ± 0.8 μm (n = 50). Microconidia were ellipsoid to fusoid and 9.77 ± 2.29 × 2.99 ± 0.65 μm (n = 50). (II) Genomic DNA was extracted by AxyPrep Multisource Genomic DNA Miniprep Kit according to the manufacturer's instructions; the sequence analysis of partial translation elongation factor-1α (TEF-1α) and RNA polymerase II second largest subunit (RPB2) were accomplished with the primers EF1/2 and RPB5F/7CR, respectively. BLAST searches of the obtained sequences had 99-100% homology with several F. sporotrichioides strains from GenBank. DNA sequences of partial TEF-1α and RPB2 were deposited in GenBank as OQ068267 and OQ068269, respectively. (III) This strain can synthesis T-2, HT-2, diacetoxyscirpenol (DAS), and Neosolaniol (NEO) toxin at the concentration of about 5000, 600, 700 and 8000 μg/kg in rice culture, respectively, according to the previous culture and analysis methods (1,2). (IV) Pathogenicity tests were conducted with the rice variety Nanjing 9108 by spraying spore suspension (106 conidia/ml) on rice spikes (5 mL per spike) at the flowering stage. Control spikes were inoculated with sterile distilled water. Three weeks after inoculation, the inoculated rice glumes showed similar symptoms with the original samples in the field. No symptoms were observed on controls. Besides, F. sporotrichioides was successfully recovered from the inoculated rice spikes but not from controls. To our knowledge, this is the first report of F. sporotrichioides causing rice panicle blight in China and this disease appears to be a serious risk to food safety and human health. Funding: This work was supported by Jiangsu Agriculture Science and Technology (CX(21)1005).

Effect of Plant Growth Regulators on Callus Induction of Black Rice (Oryza sativa L.)

Aims: Black rice of Manipur is known for its aroma and nutritional quality. As per the reports on tissue culture of rice, callus induction response of traditional cultivars was much lower than the modern high yielding varieties. Considering the importance of the black rice, and effort was taken to standardized callus induction protocol of black rice of Manipur.
 Study Design: Complete Randomized Design.
 Place and Duration of Study: Department of Seed Science and Technology, Faculty of Agriculture, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar 736165, West Bengal, India, between June 2020 and July 2023.
 Methodology: Mature seeds of two black rice varieties used in this work. The seeds were dehusked manually, washed with running tap water. Then sterilized with 1% bavistin and again washed with running tap water. Seeds were surface sterilized with 0.2% HgCl2 for 15 minutes. Sterilised seeds were rinsed with sterile distilled water inside laminar air flow hood. The seeds were blotting dry using autoclaved tissue paper and sterile seeds were cultured with the scutellum pointing up wards on callus induction medium fortified with different concentrations and combinations of plant growth regulators.
 Results: MS medium fortified with 2,4-D was found to be better than picloram and TDZ to induce callus and the 2,4-D @ 1.00 mg/L and 2,4-D 2.00 mg/L was found to be the best concentrations. Callus health was also good when MS medium invigorated with 2,4-D.
 Conclusion: An efficient embryogenic callus induction and plantlet regeneration protocol for black rice was established by using mature seeds. In callus induction studies, with different concentrations of PGR, 2,4-D, higher callus induction frequency was observed with 1.00 mg/L 2,4-D and 2,4-D @ 2 mg/L for both rice varieties.

Higher Food Yields and Lower Greenhouse Gas Emissions from Aquaculture Ponds with High-Stalk Rice Planted.

Aquaculture ponds are an important artificial aquatic system for global food fish production but also are a hot spot of greenhouse gas (GHG) emissions. The GHG mitigation strategy and the underlying mechanism for aquaculture ponds are still poorly understood. In this study, we conducted a 2 year field experiment to determine the effects of planting high-stalk rice (an artificially bred emergent plant for ponds) on GHG emissions from aquaculture ponds. Our results showed that planting high-stalk rice reduced CH4 emission by 64.4% and N2O emission by 76.2% over 2 years. Planting high-stalk rice significantly increased the content of O2 and the abundance of pmoA in the sediment, thus prompting CH4 oxidation in the ponds. The reduction of N2O emission from ponds was attributed to the decreased inorganic nitrogen, amoA-B and nirS in the sediment induced by rice. Furthermore, high-stalk rice culture in the pond increased shrimp yields and gained rice yields, resulting in a significant reduction of yield-scaled global warming potential. Our findings suggest that breeding appropriate emergent aquatic plants is a potential pathway to mitigate GHG emission from aquaculture ponds with more food yields and economic benefits.

Possible involvement of nitric oxide in promoting the initial growth of rice seedlings at low temperature by inoculation of Bacillus pumilus strain TUAT1 spores

ABSTRACT Bacillus pumilus strain TUAT1, a type of plant growth – promoting rhizobacteria (PGPR), is used as an ingredient in biofertilizer. Although we confirmed that B. pumilus TUAT1 promotes the growth of rice seedlings at 25°C, this effect has not been shown at lower temperatures. In this study, we confirmed that inoculation of rice seedlings with spores of B. pumilus TUAT1 promoted seedling emergence from soil and subsequent growth at 15°C. Except for the effect on root growth, these effects disappeared when seeds were treated with 2–4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, a nitric oxide (NO) scavenger, simultaneously with B. pumilus TUAT1 inoculation. Increased NO accumulation was detected in seed embryos 3 h after inoculation, suggesting that NO plays a role in the effects of B. pumilus TUAT1 inoculation. Transcriptome analysis using RNA-seq suggested the involvement of immune responses and cytochrome respiratory pathways in increasing NO levels in embryos after inoculation with B. pumilus TUAT1. Transcriptome analysis also indicated that transcription of genes involved in cold tolerance was accelerated in embryos following the increase in NO resulting from inoculation with B. pumilus TUAT1. These findings suggest that a novel NO signaling mechanism is involved in PGPR-induced growth promotion in plants. These results also indicate that inoculation with B. pumilus TUAT1 spores may help overcome the initial growth failure of seedlings in direct sowing culture of rice in cold regions.

Echinochloa in mid-southern U.S. and California rice: What is known and what are the knowledge gaps?

AbstractSeveral species of Echinochloa P. Beauv., introduced at multiple events, have established themselves as a persistent concern for U.S. rice production. In this review, we highlight the key biological characteristics of economically relevant Echinochloa in U.S. rice production, revisit their historical trajectory, and suggest research directions for their management with special reference to barnyardgrass. Ecologically differentiated Echinochloa species have a distinct association with rice culture methods that have been practiced for the last few decades, barnyardgrass being historically predominant in drill-seeded rice in the mid-South, and early watergrass and late watergrass in water-seeded California rice. However, the emerging evidence challenges the dogma that other Echinochloa species for specific regions are of less importance. Primarily managed by the water-seeding method of rice culture in the early years of the 20th century, Echinochloa species have persisted in the sophisticated U.S. rice culture through the evolution of resistance to herbicides in recent decades. Accumulating knowledge, including those of recent genomic insights, suggests the rapid adaptability of Echinochloa. The last decade has seen a (re)emergence of nonchemical methods as a key component of sustainable management, among which use of harvest weed seed control (HWSC) methods and cover crops in the mid-South and stale-drill seeding in California are being considered as potential methods for managing Echinochloa. In recent years, furrow-irrigated rice has rapidly supplanted a significant proportion of conventionally flooded rice in the mid-South, whereas the propensity for compromised continuous submergence is increasing in California rice. On the cusp of this shift, the question at the forefront is how this will affect Echinochloa interference in rice and how this change will dictate the management efforts. Future research will lead to the development of a clear understanding of the impact of the changing agroecosystems on Echinochloa species and their response to the prospective integrated control interventions.

Unmanned Aerial Vehicle Direct Seeding Versus Ground Seeding Mechanization Services in Smallholder Farming Systems of North West IGP on Energy Use Efficiency and Quality of Rice Culture: A Review

Various sectors use AI technologies to increase output and productivity. AI in agriculture also enables farmers to boost productivity while minimizing harmful environmental effects. AI is transforming the food-processing industry, where agricultural emissions have dropped by 20%. Mechanization is once again one of the top development policy targets for changing the smallholder agricultural system in the north west IGP. To support public investment or company development programs, however, previous and ongoing efforts frequently suffer from a lack of scientific data on end-user effective demand for various sorts of mechanical improvements. Rice production involves intricate agronomic procedures. Seeding, fertilizing, and pesticide application are labour- and time-intensive tasks that have low automation efficiency. Currently, a lot of research focuses on the single UAV operation on rice, but there aren't many applications that cover the entire process of sowing, fertilizing, and applying pesticides. Based on the intelligent operating platform, a mUAV was created to oversee the planting of rice. This aircraft accomplished three tasks on the same flight platform: seeding, fertilizer application, and pesticide application. Machine design was carried out using simulations of CFD. The cultivation patterns of mechanical rice direct seeder, mechanical rice transplanter, and mUAV seeding were compared to perform a comparative evaluation of the entire process. With improved rice automation, fewer labour inputs, and lower costs, it is intended that this evaluation will offer new machinery for rice farming patterns in various conditions.

Asperphenalenones Isolated from the Biocontrol Agent Clonostachys rosea and Their Antimicrobial Activities.

Clonostachys rosea is a fungus widely distributed on Earth and has a high capacity to adapt to complex environments in soil, plants, or sea. It is an endophyte that can be used as a potential biocontrol agent to protect plants from pathogenic fungi, nematodes, and insects. However, the spectrum of secondary metabolites produced by C. rosea has only scarcely been studied. In the present study, eight new phenalenones, asperphenalenones F-M (1-8), together with two known derivatives, asperphenalenones E and B (9 and 10), were isolated from the axenic rice culture of this fungus. The structures of the new compounds were elucidated by nuclear magnetic resonance, high-resolution electrospray ionization mass spectrometry, electronic circular dichroism, and gas chromatography-mass spectrometry analyses. Asperphenalenones J-M (5-8) are unusual phenalenone adducts that are conjugated to diterpenoid glycosides. Asperphenalenones F and H showed moderate antibacterial activity against methicillin-resistant Staphylococcus aureus, with minimal inhibitory concentrations of 12.5 and 25 μM, respectively. Asperphenalenone B exhibited low antiviral activity against the human immunodeficiency virus replication. Furthermore, asperphenalenones F and H exhibited low cytotoxicity against Jurkat cells, while all other compounds were devoid of cytotoxicity.

Steroids from Toona sureni-derived Endophytic Fungi Stemphylium sp. MAFF 241962 and Their Heme Polymerization Inhibition Activity

Abstract Antimalarial drug resistance is a major cause of the increasing incidence of malaria worldwide, necessitating an urgent demand for the development of new antimalarial drugs. However, the availability of bioactive natural compounds derived from plants is often limited. To address this issue, continuous exploration of bioactive secondary metabolites from endophytic fungi derived from medicinal plants has been recognized as a viable alternative. Therefore, this research aimed to isolate and characterize three ergosteroids, namely isocyathisterol (1), ergosterol-5,8-peroxide (3), cerevisterol (4), and a phytosterol, β-sitosterol (2), from the rice cultures of endophytic fungus Stemphylium sp. MAFF 241962, derived from Toona sureni. Endophytic fungi species were determined using molecular analysis of the internal transcribed region (ITS) of the ribosomal DNA. After comparing the sequence data to the NCBI database using BLAST, endophytic fungi were identified as Stemphylium sp. 241962 with 100% similarity. The chemical structures were elucidated using spectroscopic methods, including 1D and 2D NMR. Antimalarial activities of compounds 1-4 were evaluated using heme polymerization inhibition activity (HPIA) method. The results showed moderate inhibition activities with IC50 values of 7.70 ± 0.11, 9.48 ± 0.09, 7.88 ± 0.10, and 8.36 ± 0.56 mg/mL, respectively, compared to positive control chloroquine diphosphate with IC50 values of 1.59 ± 0.03 mg/mL. Keywords: Steroid, Stemphylium sp., Toona sureni, Antimalarial activity, Heme polymerization inhibition

Behavioral and histopathological changes of Clarias gariepinus as a predatory fish against Culex pipiens larvae following exposure to sublethal concentration of quinclorac and bensulfuron-methyl based herbicide

Summary Clarias gariepinus is one of the widespread culturable freshwater fish species in Africa, which is prevalent in various natural and human-made aquatic habitats including rice-fish system. This fish species displays predation potential on the aquatic stages of mosquitoes. Bensulfuron-methyl and quinclorac are herbicide active substances that have been extensively applied in rice culture in Egypt and other countries worldwide. This study assessed the adverse effects of sublethal concentration of a commercial herbicide formulation containing quinclorac and bensulfuron-methyl on the predation potential of C. gariepinus female and male predatory fish on Culex pipiens mosquito larvae. Also, stomach and intestine histopathology of the treated fish was investigated. The exposure of C. gariepinus to sublethal concentration of quinclorac and bensulfuron-methyl based herbicide produced detrimental effects on prey consumption and histopathological changes in the stomach and intestine of the fish. The mosquito consumption by the treated female and male fish decreased significantly compared to the untreated fish of both sexes. The histological changes in the intestines were hyperplasia of the intestinal epithelium and goblet cells; edema of lamina propria and broad intestinal villi, and distortion in intestinal villi in comparison to control. The stomach histopathology changes were necrosis and sloughing of mucosal epithelium with severe damage of sub-mucosa. Thus, the tested herbicide at sublethal concentration on C. gariepinus decreased the prey consumption on mosquito larvae and caused histopathological alterations in the fish that may impair its digestive physiology. These findings suggest a threat of the tested herbicide to C. gariepinus survival and potential as a native successful biocontrol agent against Cx. pipiens larvae.

NLR 3186: A Long Duration Blast Resistant Rice Culture Suitable for Irrigated Ecology of Andhra Pradesh

The culture NLR 3186 was derived from a cross of NLR 28523 / Secandro Brazelio (5720-11-1-3-1) through Pedigree method of breeding at Agricultural Research Station, Nellore. It recorded an average yield increase of 19.97% over the check NLR 33892 in the station trials. In Multi Location Trial conducted for 2 years, it recorded 11.26% increase over the checks used for testing MTU 1061.I n 3 years of minikit testing the entry NLR 186 recorded 8.3% higher grain yield than the check varieties tested. In AICRIP trial during 2012-13, it recorded on par with the national check MTU 7029 (4249 kg/ha). It has non-lodging nature, high yielding, nitrogen responsive, with medium green foliage, low shattering and complete exertion of panicle. It was tolerant to leaf blast, neck blast and sheath rot. It has good cooking and chemical quality as it exhibits intermediate and desired values of ASV, gel consistency, good linear elongation ratio and amylase content. It also possesses good head rice recovery with translucent grains which is very much desired for marketing.

Flooded rice variables from high-resolution multispectral images and machine learning algorithms

Remote spectral detection via orbital, aerial or terrestrial platforms is considered a valuable tool for non-destructive real-time estimation of the Leaf Area Index (LAI), the status of plant N, and grain yield. In this context, this study aims to build predictive models from very high-resolution multispectral images as input variables with Machine Learning (ML) algorithms to generate indirect estimates of LAI, Narea, and grain yield for flooded rice culture. Multispectral images were acquired through a Sequoia® camera aboard the Phantom 4® Pro platform, during five phenological crop stages. In addition to the spectral bands, nine vegetation indices were taken as predictors of the response variables derived from the site survey. The Spearman's test demonstrated a more significant correlation at the end of the vegetative stage (V7) and the beginning of the reproductive stage (R1) to predict the studied variables. Furthermore, the Support Vector Machine (SVM) models showed high fit and good generalization capability in flooded rice cultivation, reinforcing the excellent combination capacity between remote sensing via Remotely Piloted Aircraft Systems (RPAS) and machine learning in precision agriculture applications.

Chitosan Modulates Volatile Organic Compound Emission from the Biocontrol Fungus Pochonia chlamydosporia.

Fungal volatile organic compounds (VOCs) are responsible for fungal odor and play a key role in biological processes and ecological interactions. VOCs represent a promising area of research to find natural metabolites for human exploitation. Pochonia chlamydosporia is a chitosan-resistant nematophagous fungus used in agriculture to control plant pathogens and widely studied in combination with chitosan. The effect of chitosan on the production of VOCs from P. chlamydosporia was analyzed using gas chromatography-mass spectrometry (GC-MS). Several growth stages in rice culture medium and different times of exposure to chitosan in modified Czapek-Dox broth cultures were analyzed. GC-MS analysis resulted in the tentative identification of 25 VOCs in the rice experiment and 19 VOCs in the Czapek-Dox broth cultures. The presence of chitosan in at least one of the experimental conditions resulted in the de novo production of 3-methylbutanoic acid and methyl 2,4-dimethylhexanoate, and oct-1-en-3-ol and tetradec-1-ene in the rice and Czapek-Dox experiments, respectively. Other VOCs changed their abundance because of the effect of chitosan and fungal age. Our findings suggest that chitosan can be used as a modulator of the production of VOCs in P. chlamydosporia and that there is also an effect of fungal age and exposure time.

Agricultural origins of corporate pro-environmental behavior

The cultural differences caused by rice cultivation between the north and south of China provide a unique perspective to study the local effect on corporate pro-environmental behavior. In this paper, we investigate the relationship between the geographical distribution of agricultural planting and corporate pro-environmental behavior. We manually collected the city-level rice planting data and used A-share listed companies’ data from 2010 to 2019 in China and found that rice culture in the external environment in which the company is embedded has a positive association with the corporate reactive pro-environmental behavior, while rice culture in the internal values which CEO provided with is positively related to the corporate proactive pro-environmental behavior. Moreover, we find that environmental policy and migration are two moderators through which rice culture affects corporate pro-environmental behavior. This study not only sheds light on the agricultural drivers behind corporate pro-environmental behavior and extends the theoretical understanding of how cultural differences caused by geographical factors within countries influence corporate decisions but also helps firms, managers, and stakeholders effectively conduct self-reflection, management, and supervision on environmental issues through farming cultural dimensions.

Screening of Rice Germplasms for their Resistance against Gall Midge, <i>Orseolia oryzae</i> Wood Mason (Biotype-3) in Ranchi, Jharkhand

An experiment was conducted to screen out twenty-three rice cultures, varieties and genotypes against rice gall midge (biotype-3) at the research farm of Birsa Agricultural University, RAC (Ranchi Agriculture College) Kanke, Ranchi during kharif season of 2017. Out of 23 genotypes, Kavya, W-1263, Abhaya, Phalguna, Lalat, BG-380-2, RD-202 and Suraksha emerged as resistant and promising against the gall midge (biotype-3), receiving silver shoot incidence below 5% even when they are grown in unprotected condition in the present studies as against the significantly and substantially higher pest incidence (i.e. SS%) recorded in case of TN- 1, IR-64 Sub-1 and IR-64 receiving 32.49%, 20.15% and 19.33%, respectively. Naveen was responsible for realization of the highest grain yield (52.70 q/ha) among all the tested rice varieties.

Efficient mitigation of arsenic accumulation in rice seedlings using in situ formed hydrous titanium oxide from aqueous titanyl amendment

The Arsenic (As) accumulation problem of plants has to be solved when exploring scattered As micro-polluted water as a new irrigation water source for food production. Herein, efficient As immobilization (1 mg-As/L) was realized by simply adding TiOSO4 (TOS) solution in the irrigation water during rice seedling cultivation. The free soluble As in the rice culture was reduced by 99.4%. Most of the As was enriched in hydrous titanium oxide (HTO) formed from in situ TOS hydrolysis (HTO-TOS), which possessed a very high specific surface area (347.6 m2/g) and the most abundant adsorption-active hydroxyl group. Adding TOS (100 mg/L) is tens of times better than adding TiO2 nanoparticles and is even better than commercial HTO at a dosage up to 1000 mg/L in As-immobilization ability. On the one hand, TOS treatment transformed soluble As to insoluble forms by the strong complexation between freshly formed active HTO and As. On the other hand, a barrier of titanium and iron plaque was formed on root surface. Benefiting from these two aspects, the As contents in rice roots and shoots were reduced by 74.6% and 95.6%, respectively. The TOS treatment strategy had no adverse influence on rice growth while promoted the root growth by 39.4% and alleviated the oxidative stress of rice seedlings. Considering its simple application manner and good As control performance, TOS treatment has great potential on in situ remediation of As-contaminated water and soil during cultivating diverse agricultural plants.

Formation of ferrihydrite induced by low pe+pH in paddy soil reduces Cd uptake by rice: Evidence from Cd isotope fractionation

Ferrihydrite (Fh) is an important iron mineral in paddy soil and is prone to phase transition during dynamic redox condition, which affects Cd distribution and induces Cd isotope fractionation across soil to rice. Here, we conducted rice culture experiments with or not Fh application under different irrigation regimes to study the relationship between Fe species and Cd availability, as well as the isotope ratio of Cd in different Cd pools in paddy soil-rice system. Fh addition under continuous flooding (FL) with the decrease of pe + pH from 9.36 to 3.44 promoted the formation of amorphous Fe oxides as increased by 120.1% and facilitated Cd immobilization along with the increase of Fe/Mn oxides bound Cd by 25.3%, compared with continuous drying (DY) treatment. The isotopically heavy Cd were preferentially enriched from soil to extractable Cd (Δ114/110Cdextractable Cd-soil = 0.39–0.62‰) and from soil to grain (Δ114/110Cdgrain-soil = 0.40–0.66‰) particularly at low pe + pH and with Fh addition, while light Cd were enriched in Fe/Mn oxides (Δ114/110CdFe/Mn oxides bound Cd-extractable Cd = −0.65 ∼ −0.14‰). Besides, the expression of transporters involved in Cd transport in rice like OsNRAMP1, OsNRAMP1, OsHMA3, OsHMA2 and OsLCT1 were suppressed under low pe + pH condition. These findings indicated that low pe + pH facilitated Cd stabilization by the existence of more amorphous iron oxides, which induced the enrichment of heavy Cd isotope in liquid phase and light in Fe/Mn (oxy)hydroxides, respectively.

Near-Infrared Fluorescent Probe for Imaging Upregulated Hydrogen Sulfide Levels in Rice under Salt and Drought Stress

Hydrogen sulfide (H2S) is a hazardous gas found in living organisms and is directly tied to our daily lives. Recent studies show that it plays a significant role in plant growth, development, and response to environmental stresses. However, few of the reported near-infrared (NIR) fluorescent probes have been applied to rice and deeply investigated the influence of the external environment on the biological molecules in its internal environment. Therefore, our team created BSZ-H2S, which has the advantage of an emission wavelength of up to 720 nm with fast response, successfully applying it to cell and zebrafish imaging. More importantly, the probe detected H2S in rice roots by in situ imaging in a facile manner and verified the existence of an upregulation process of H2S in response to salt and drought stress. This work provides a concept for the intervention of external stresses in rice culture.

Salinity extrusion and resilience of coastal aquaculture to the climatic changes in the southwest region of Bangladesh

The southwest coastal belt of Bangladesh is characterized by a fresh and saline water interaction which gives rise to a discrete inter-saline freshwater convergence zone (ICZ). Hydrology and farming along this transition zone is influenced by upstream and downstream abiotic factors including salinity intrusion and water flow. To better understand the changing geography of the transitional ICZ line and the relative influence of these hydrological events on farming therein, the recent study compared relative changes from 2010 to 2014 based on qualitative and quantitative survey work with 80 households of 4 villages (Shobna, Faltita, Badukhali and Rudaghora) from Khulna and Bagerhat district. Contrary to the conventional hotcake climate change induced salinity intrusion the study found a significant decrease in saltwater influx and increased freshwater volume in the ICZ villages, reflecting a seaward movement trend. Farmer perception shifted to low saline and freshwater in many areas where it was high saline and medium saline in 2010. The factual and perceived salinity were varied from 1 ± 0.44 to 2 ± 0.77 ppt in the studied villages. To confront the condition farmer diversified their farming pattern from single crop like either only shrimp or prawn culture to concurrent culture of shrimp-prawn, shrimp, prawn and rice with an increased production of (68-204 kg/ha), finfish (217-553 kg/ha) and dyke crop (92–800 kg/ha). Thus, affecting the socioeconomic condition of the farmer with an increase in average monthly income, reported for the better-off classes in 2014, ranged from 14,300 to 51,667 BDT and for the worse-off ranged from 5000 to 9900 BDT. In contrast, this average monthly income was 9500- 27,000 for better-off and 3875 - 8600 for worse-off classes, reported in 2010. Besides, farming areas (average 17% for better-off and −0.5% for worse-off) and land leasing (average increment rate per ha 50%) also increased among the surveyed farmers, reported in 2014 compared to 2010. In addition, several adaptation strategies like unrefined salt use, change of water use, diversification through prawn, finfish and dyke crops along with traditional shrimp and overall land use change have a positive impact on farmer’s economic and nutritional security as well as farming intensity. The study showed a unique attributes of salinity extrusion in micro-level of ICZ line where farmers intensified farming system with indigenous knowledge to secured their livelihoods.

Genetic divergence studies for yield and quality traits in high protein landraces of rice (Oryza sativa L.)

The present study was undertaken to study the extent of genetic diversity in high protein rice landraces with respect to yield, yield components and quality characters. In this direction, 30 high protein rice landraces, collected from different parts of country by ICAR-Indian Institute of Rice Research (ICAR-IIRR), Hyderabad along with the high protein check, CR DHAN 310 were evaluated during Kharif 2021 at ICAR-IIRR farm located at International Crops Research Institute of Semi Arid Tropics (ICRISAT), Hyderabad. The study examined the genetic divergence of high protein rice cultures for yield, quality and nutritional parameters. Multivariate analysis techniques of Mahalanobis D2 and Principal Component Analysis (PCA) were used to estimate the genetic diversity in the experimental material. In Mahalanobis D2, the 31 high protein rice cultures were divided into six clusters. Cluster I had highest number of rice cultures (19), followed by Cluster III and V with five, four cultures, respectively. The clusters, II, IV, VI were mono-genotypic. It was discovered that grouping of these cultures into several clusters was random and was not related to geographical diversity. Inter-cluster distances between clusters V and VI were maximum. Cluster V had also exhibited higher intra-cluster distance. Further, Cluster VI had showed maximum yield plant-1, grains per panicle-1, zinc content and test weight, while, Cluster V had recorded high protein content. The greatest contribution to genetic divergence was recorded by yield plant-1 (21.60%), followed by iron (10.54%) and zinc content (9.54%). In Principal Component Analysis, the first five Principal Components (PCs) with eigen values >1 accounted for cumulative contribution of 67.69% to the total variability. The three traits, yield plant-1, iron content, and amylose content contributed the most to variability. The 2D scatter diagram exhibited 18 different clusters, out of which 11 clusters were mono-genotypic. Mahalanobis D2 Statistic and PCA concluded maximum genetic diversity between the landraces, JAK 248-3 and JAK 638 with JAK 611.