The yield of direct-seeded rice(DSR)was constrained by inadequate grain filling.Recent studies have indicated that paclobutrazol application plays a significant role in enhancing crop agronomic traits and increasing y...The yield of direct-seeded rice(DSR)was constrained by inadequate grain filling.Recent studies have indicated that paclobutrazol application plays a significant role in enhancing crop agronomic traits and increasing yield.This study aimed to examine the effects of paclobutrazol seed soaking(PSS)on non-structural carbohydrate accumulation and grain enrichment in DSR,potentially providing a theoretical foundation for achieving high-yield DSR cultivation.The experiment utilized two rice varieties,Jiyujing(JYJ)and Jijing305(JJ305),with seeds soaked in paclobutrazol concentrations of 0 mg L^(−1) and 100 mg L^(−1).PSS demonstrated increased chlorophyll content,net photosynthetic rate,and leaf area,as well as an extended photosynthetic function period during the filling stage.It also elevated soluble sugar and starch contents in the flag leaf(during the filling stage)and stem sheath(after heading),decreased starch content in the top panicle while increasing it in the middle and lower panicle during the filling stage,and enhanced spikelet per unit area and seed setting rate,thereby improving DSR yield.In conclusion,PSS enhanced the photosynthetic capacity of DSR during the filling stage,coordinated the filling process of superior and inferior grains,maintained source-sink balance,and facilitated stable and orderly filling,ultimately resulting in improved yield.展开更多
[Objective] This study aimed to investigate the effect of direct-seeding with non-flooding and wheat residue returning patterns on greenhouse gas emission from rice paddy. [Method] Two rice cultivars currently used in...[Objective] This study aimed to investigate the effect of direct-seeding with non-flooding and wheat residue returning patterns on greenhouse gas emission from rice paddy. [Method] Two rice cultivars currently used in the production, Yangdao 6 （an indica） and Yangjing 4038 （a japonica）, were field grown using a direct-seeding method, and four treatments, wheat straw incorporation into soil and traditional flooding （SlF）, non-flooding and wheat straw mulching （NSM）, non-flooding and wheat straw incorporation into soil （NSl） and traditional flooding （no straw returned, Control, TF）, were imposed after sowing to maturity. Effects of direct-seeding with non-flooding and wheat residue returning patterns on CH4, N20 and CO2 emissions were investigated by using the method of static chamber-gas chromatographic tech- niques. [Result] Grain yield showed no significant difference between non-flooding and flooding treatments, but was significantly higher under the SlF than under any other treatments. The emission flux of CH4 and CO2 under TF and SlF exhibited a single peak curve, while changed little under the NSl and NSM The emission flux of N2Oshowed multiple perk curves for all the treatments. Compared with TF, SlF significantly increased mean emission flux of CH4 or N2O, decreased emission of N20, while NSl and NSM significantly decreased the mean emission flux of OH4, and increased emission flux of N2O and CO2. SIF also increased Green Warm Potential （GWP） of CH4, N2O and CO2 and the GWP per unit grain yield by 47.3%- 53.7% and 32.2%-39.4%, respectively. Both NSl and NSM decreased GWP by 24.2%-29.6% and 30.1%-35.5%, and the GWP per unit grain yield was decreased by 21.7-27.2% and 25.6%-31.1%, respectively. [Conelusion] both NSl and NSM could significantly reduce greenhouse effect of CH4, N2O and CO2 meanwhile maintain a high grain yield.展开更多
The sustainability of rice production continues to be a subject of uncertainty and inquiry attributed to shifts in climatic conditions. In light of the impending climate change crisis and the high labor and water cost...The sustainability of rice production continues to be a subject of uncertainty and inquiry attributed to shifts in climatic conditions. In light of the impending climate change crisis and the high labor and water costs accompanying it, direct-seeded rice(DSR) is unquestionably one of the most practical solutions. Despite its resource and climate-friendly advantages, early maturing rice faces weed competitiveness and seedling establishment challenges. Resolving these issues is crucial for promoting its wider adoption among farmers, presenting it as a more effective sustainable rice cultivation method globally. Diverse traditional and contemporary breeding methods are employed to mitigate the limitations of the DSR approach, leveraging advanced techniques such as speed breeding and genome editing. Focusing on key traits like mesocotyl length elongation, early seedling vigor, root system architecture, and weed competitiveness holds promise for transformative improvements in DSR adaptation at a broader scale within farming communities. This review aims to summarize how these features contribute to increased crop production in DSR conditions and explore the research efforts focusing on enhancing DSR adaptation through these traits. Emphasizing the pivotal role of these game-changing traits in DSR adaptation, our analysis sheds light on their potential transformative impact and offers valuable insights for advancing DSR practices.展开更多
Mesocotyl elongation is a key trait influencing seedling emergence and establishment in direct-seeding rice cultivation.The phytohormone gibberellin(GA)has positive effects on mesocotyl elongation in rice.However,the ...Mesocotyl elongation is a key trait influencing seedling emergence and establishment in direct-seeding rice cultivation.The phytohormone gibberellin(GA)has positive effects on mesocotyl elongation in rice.However,the physiological and molecular basis underlying the regulation of mesocotyl elongation mediated by GA priming under deep-sowing conditions remains largely unclear.In the present study,we performed a physiological and comprehensive transcriptomic analysis of the function of GA priming in mesocotyl elongation and seedling emergence using a direct-seeding japonica rice cultivar ZH10 at a5-cm sowing depth.Physiological experiments indicated that GA priming significantly improved rice seedling emergence by increasing the activity of starch-metabolizing enzymes and compatible solute content to supply the energy essential for subsequent development.Transcriptomic analysis revealed 7074 differentially expressed genes(false discovery rate of<0.05,|log2(fold change)|of≥1)after GA priming.Furthermore,gene ontology(GO)and Kyoto encyclopedia of genes and genomes(KEGG)enrichment analyses revealed that genes associated with transcriptional regulation,plant hormone biosynthesis or signaling,and starch and sucrose metabolism were critical for GA-mediated promotion of rice mesocotyl elongation.Further analyses showed that the expression of the transcription factor(TF)genes(v-myb avian myeloblastosis viral oncogene homolog(MYB)alternative splicing 1(MYBAS1),phytochrome-interacting factors 1(PIF1),Oryza sativa teosinte branched 1/cycloidea/proliferating cell factor 5(Os TCP5),slender 1(SLN1),and mini zinc finger 1(MIF1)),plant hormone biosynthesis or signaling genes(brassinazole-resistant 1(BZR1),ent-kaurenoic acid oxidase-like(KAO),GRETCHEN HAGEN 3.2(GH3.2),and small auxin up RNA 36(SAUR36)),and starch and sucrose metabolism genes(α-amylases(AMY2 A and AMY1.4))was highly correlated with the mesocotyl elongation and deep-sowing tolerance response.These results enhance our understanding of how nutrient metabolism-related substances and genes regulate rice mesocotyl elongation.This may facilitate future studies on related genes and the development of novel rice varieties tolerant to deep sowing.展开更多
Rice direct seeding technology is an appealing alternative to traditional transplanting because it conserves labor and irrigation resources.Nevertheless,there are two main issues,salt stress and alkaline stress,which ...Rice direct seeding technology is an appealing alternative to traditional transplanting because it conserves labor and irrigation resources.Nevertheless,there are two main issues,salt stress and alkaline stress,which contribute to poor emergence and seedling growth,thereby preventing the widespread adoption and application of this technique in the Ningxia Region of China.Therefore,to determine whether germination can be promoted by mixed-oligosaccharide(KP)priming(in which seeds are soaked in a KP solution before sowing)under salt and alkaline stress,a proteomics study was performed.KP-priming significantly mitigated abiotic stress,such as salt and alkaline stress,by inhibiting root elongation,ultimately improving seedling establishment.By comparing the proteomics analyses,we found that energy metabolic pathway was a vital factor in KP-priming,which explains the alleviation of salt and alkaline stress.Key proteins involved in starch mobilization,pyruvate mobilization,and ATP synthesis,were up-regulated by KP-priming,significantly blocking salt and alkaline-triggered starch accumulation while enhancing pyruvate metabolism.KP-priming also up-regulated ATP synthase to improve energy efficiency,thereby improving ATP production.In addition,it enhanced antioxidant enzymatic activities and reduced the accumulation of reactive oxygen species.All of these factors contributed to a better understanding of the energy regulatory pathway enhanced by KP-priming,which mediated the promotion of growth under salt and alkaline conditions.Thus,this study demonstrated that KP-priming can improve rice seed germination under salt and alkaline stress by altering energy metabolism.展开更多
The chalcone isomerase gene OsCHI,one of the key genes in the flavonoid biosynthesis pathway,plays an important role in rice(Oryza sativa)resistance to abiotic stresses.This study reveals how the chalcone isomerase ge...The chalcone isomerase gene OsCHI,one of the key genes in the flavonoid biosynthesis pathway,plays an important role in rice(Oryza sativa)resistance to abiotic stresses.This study reveals how the chalcone isomerase gene family member OsCHI3 participates in rice responses to drought stress through the regulation of flavonoid biosynthesis.Overexpression of OsCHI3 increased the tolerance of rice to drought stress.In contrast,CRISPR/Cas9-mediated deletion of OsCHI3 reduced the drought tolerance of rice,an effect that is reversed by exogenous ABA treatment.Transcriptomic and physiological biochemical analyses indicated that flavonoids regulated by OsCHI3 not only scavenge reactive oxygen species(ROS)but also increase drought tolerance in rice by stimulating ABA biosynthesis through the regulation of OsNCED1 and OsABA8ox3 expression.These findings demonstrate that OsCHI3 increases drought stress tolerance in rice by activating the antioxidant defense system and the ABA metabolic pathway,providing new clues for drought-resistant rice breeding research.展开更多
Pre-harvest sprouting(PHS)describes the germination of physiologically mature grains in spikes prior to harvest in cereal crops.PHS could seriously decrease grain yield and quality,which makes it a major constraint to...Pre-harvest sprouting(PHS)describes the germination of physiologically mature grains in spikes prior to harvest in cereal crops.PHS could seriously decrease grain yield and quality,which makes it a major constraint to cereal production worldwide.A number of PHS-associated genes in cereals have been reported;however,the molecular mechanisms underlying PHS remain largely elusive.Here,we report a CRISPRCas9 mutant with severe PHS in a paddy field.The mutated gene OsMFT2 encodes a phosphatidylethanolamine-binding protein(PEBP).Intriguingly,the OsMFT1,in the same PEBP family,had the opposite effect in controlling rice PHS as does OsMFT2.Germination tests of seeds of chimeric protein-expressing plants revealed that the fourth exon conferred the antagonistic activity of OsMFT1 and OsMFT2 in rice PHS.Additionally,two lines of these plants showed elevated grain numbers per panicle,implying that chimeric protein has potential to significantly increase yield.Moreover,transcriptome analysis and genetic studies indicated that OsMFT1 and OsMFT2 performed opposing functions in rice PHS owing to three co-regulated genes that being contrastingly affected by OsMFT1 and OsMFT2.Overall,it seemed that the proper combination of PEBP family members could obtain optimal PHS resistance and high yield.展开更多
Viruses are significant pathogens causing severe plant infections and crop losses globally.The resistance mechanisms of rice to viral diseases,particularly Southern rice black-streaked dwarf virus(SRBSDV),remain poorl...Viruses are significant pathogens causing severe plant infections and crop losses globally.The resistance mechanisms of rice to viral diseases,particularly Southern rice black-streaked dwarf virus(SRBSDV),remain poorly understood.In this study,we assessed SRBSDV susceptibility in 20 Xian/indica(XI)and 20 Geng/japonica(GJ)rice varieties.XI-1B accessions in the Xian subgroup displayed higher resistance than GJ accessions.Comparative transcriptome analysis revealed changes in processes like oxidoreductase activity,jasmonic acid(JA)metabolism,and stress response.JA sensitivity assays further linked antiviral defense to the JA pathway.These findings highlight a JA-mediated resistance mechanism in rice and offer insights for breeding SRBSDV-resistant varieties.展开更多
Branching is a critical aspect of plant architecture that significantly impacts the yield and adaptability of staple cereal crops like rice and wheat.Cereal crops develop tillers during the vegetative stage and panicl...Branching is a critical aspect of plant architecture that significantly impacts the yield and adaptability of staple cereal crops like rice and wheat.Cereal crops develop tillers during the vegetative stage and panicle or spike branches during the reproductive stage,respectively,both of which are significantly impacted by hormones and genetic factors.Tillering and panicle branching are closely interconnected and exhibit high environmental plasticity.Here,we summarize the recent progress in genetic,hormonal,and environmental factors regulation in the branching of rice and wheat.This review not only provides a comprehensive overview of the current knowledge on branching mechanisms in rice and wheat,but also explores the prospects for future research aimed at optimizing crop architecture for enhanced productivity.展开更多
The RING-type E3 ligase OsBBI1 regulates rice resistance against Magnaporthe oryzae through modifying cell wall defenses.In this study,we report the function of an OsBBI1 substrate,eukaryotic translation initiation fa...The RING-type E3 ligase OsBBI1 regulates rice resistance against Magnaporthe oryzae through modifying cell wall defenses.In this study,we report the function of an OsBBI1 substrate,eukaryotic translation initiation factor OseIF5A4,in rice immunity.OsBBI1 interacts with OseIF5A4 and other four members of the OseIF5A family.The RING domain in OsBBI1 and the eIF-5a domain in OseIF5A4 are critical for the OsBBI1-OseIF5A4 interaction.OsBBI1 ubiquitinates OseIF5A4 and mediates its degradation in vitro and in vivo.Moreover,the expression of OseIF5A4 was upregulated during early stage of compatible interaction but downregulated in incompatible interaction between rice and M.oryzae.Knockout of OseIF5A4 enhances rice immunity against M.oryzae and Xanthomonas oryzae pv.oryzae,boosts pattern-triggered immune responses,and strengthens pathogen-induced defense responses(e.g.,expression of defense genes,accumulation of reactive oxygen species and reinforcement of cell wall).However,overexpression of OseIF5A4 attenuates rice immunity and immune responses.These results demonstrate that OseIF5A4,a substrate of the immunity-associated E3 ligase OsBBI1,negatively regulates rice immunity against M.oryzae and X.oryzae pv.oryzae through modulating pathogen-induced defense responses,highlighting the importance of the protein translational machinery in rice immunity.展开更多
The emergence of novel phytopathogens and the accelerated spread of plant diseases to new regions,driven by global climate change,constitute significant threats to agricultural resources.Rice,a major tropical staple c...The emergence of novel phytopathogens and the accelerated spread of plant diseases to new regions,driven by global climate change,constitute significant threats to agricultural resources.Rice,a major tropical staple crucial for global food security,possesses six transcription factor superfamilies-AP2/ERF,bHLH,bZIP,MYB,NAC,and WRKY-that function in innate immunity against pathogens.We review their biological functions and regulatory mechanisms in rice immunity.展开更多
Alzheimer’s disease(AD)is a neurodegenerative disorder associated with brain aging,and the accumulation ofβ-amyloid(Aβ)and hyperphosphorylated Tau proteins are key pathological features.Currently,drugs for the trea...Alzheimer’s disease(AD)is a neurodegenerative disorder associated with brain aging,and the accumulation ofβ-amyloid(Aβ)and hyperphosphorylated Tau proteins are key pathological features.Currently,drugs for the treatment of AD are mainly single-targeted,but the complex pathogenesis of AD makes it difficult to achieve the desired results.Therefore,the development of multitargeted therapies is crucial for future interventions.Rice bran oil(RBO)has been recognized as an edible oil with several health benefits,but its effects on AD caused by brain aging remain underexplored.In this study,the effects of RBO on memory dysfunction in D-galactose(D-gal)mice and its molecular mechanisms were investigated via in vivo and in silico methods from the perspective of AD pathologies.Our results suggested that compounds in RBO could modulate the activities of Aβprecursor protein cleaving enzyme 1(BACE1),mitogen-activated protein kinase 3(MAPK3),matrix metalloproteinase 3(MMP3),and intercellular adhesion molecule 1(ICAM1),leading to inhibition of Aβaccumulation and Tau protein hyperphosphorylation.Moreover,RBO reduced Aβ-induced oxidative stress by inhibiting the activity of mouse double minute 2 homolog(MDM2)and cyclic adenosine monophosphate(cAMP)response element binding protein binding protein(CREBBP),and attenuated neuroinflammation by inhibiting the activity of nitric oxide synthase 2(NOS2)and reducing Aβaccumulation and Tau protein hyperphosphorylation.Additionally,α-linolenic acid in RBO exhibited inhibitory effects on D-gal-induced apoptosis in PC12 cells through modulation of NOS2,MDM2,ICAM1,and phospho-extracellular signal-regulated kinase 1/2(p-ERK1/2).Similarly,stigmastanol inhibited apoptosis in D-gal-induced PC12 cells through the regulation of NOS2.Thus,RBO can be considered as a potential functional food to attenuate AD owing to its multicomponent and multitarget effects.展开更多
Rice sheath blight(RSB)is a major destructive disease impeding rice production.Identifying key germplasm resources with increased resistance remains a challenge.However,the mechanisms underlying disease resistance are...Rice sheath blight(RSB)is a major destructive disease impeding rice production.Identifying key germplasm resources with increased resistance remains a challenge.However,the mechanisms underlying disease resistance are not yet fully understood.Cytochrome P450 monooxygenases(CYP450s)serve biosynthesis and metabolic detoxification functions in plants,but there is limited information about their role in the response induced by RSB.This study demonstrated that CYT02 belongs to the CYP73A100 subfamily and is a typical member of the CYP450s.Overexpression(OE)in rice of the cytochrome P450 monooxygenase cyt02 conferred increased resistance to RSB and increased vegetative tillering.Cyt02 may increase RSB resistance by regulating plant hormone synthesis,regulate reactive oxygen species(ROS)by coordinating the activity of antioxidant enzymes,and initiate phytoalexin synthesis in response to fungal infection.These research findings have laid a foundation for a deeper understanding of the function of cyt02 and offered a potential target gene for breeding rice varieties resistant to sheath blight.展开更多
The high labor demand during rice seedling cultivation and transplantation poses a significant challenge in advancing machine-transplanted rice cultivation.This problem may be solved by increasing the seeding rate dur...The high labor demand during rice seedling cultivation and transplantation poses a significant challenge in advancing machine-transplanted rice cultivation.This problem may be solved by increasing the seeding rate during seedling production while reducing the number of seedling trays.This study conducted field experiments from 2021 to 2022,using transplanting seedling ages of 10 and 15 days to explore the effects of 250,300,and 350 g/tray on the seedling quality,mechanical transplantation quality,yields,and economic benefits of rice.The commonly used combination of 150 g/tray with a 20-day seedling age in rice production was used as CK.The cultivation of seedlings under a high seeding rate and short seedling age significantly affected seedling characteristics,but there was no significant difference in seedling vitality compared to CK.The minimum number of rice trays used in the experiment was observed in the treatment of 350-10(300 g/tray and 10-day seedling age),only 152-155 trays ha^(-1),resulting in a 62%reduction in the number of trays needed.By increasing the seeding rate of rice,missed holes during mechanical transplantation decreased by 2.8 to 4%.The treatment of 300-15(300 g/tray and 15-day seedling age)achieved the highest yields and economic gains.These results indicated that using crop straw boards can reduce the application of seedling trays.On that basis,rice yields can be increased by raising the seeding rate and shortening the seedling age of rice without compromising seedling quality.展开更多
Bacterial blight(BB),caused by Xanthomonas oryzae pathovar oryzae(Xoo),poses a significant threat to rice production,particularly in Asia and West Africa.Breeding resistance against BB in elite rice varieties is cruci...Bacterial blight(BB),caused by Xanthomonas oryzae pathovar oryzae(Xoo),poses a significant threat to rice production,particularly in Asia and West Africa.Breeding resistance against BB in elite rice varieties is crucial to advancing rice breeding program and supporting smallholder farmers.Transcription Activator-Like effectors(TALes)are key virulence factors in Xoo,with some targeting the susceptibility(S)genes such as the sugar transporter SWEET genes in rice.Among these,SWEET14 is an important S gene,with its promoter bound by the TALe TalC which exists across all sequenced African Xoo isolates.In the present study,we utilized CRISPR/Cas9-based cytidine and adenine base editors to alter the effector binding element(EBE)of TalC in the promoter of SWEET14 in rice cultivars Kitaake,IR24,and Zhonghua 11.Mutations with C to T changes in EBE led to reduced SWEET14 induction by TalC-containing Xoo strains,resulting in resistance to African Xoo isolates reliant on TalC for virulence.Conversely,A to G changes retained SWEET14 inducibility and susceptibility to Xoo in edited lines.Importantly,no off-target mutations were detected at predicted sites,and the edited lines exhibited no obvious defects in major agronomic traits in Kitaake.These results underscore the effectiveness of base editing systems for both molecular biology research and crop improvement endeavors.展开更多
The ratooning system enhances agricultural efficiency by reducing secondary sowing and resource input while maintaining rice yield parity with double cropping.However,the prolonged growth duration of the rice ratoonin...The ratooning system enhances agricultural efficiency by reducing secondary sowing and resource input while maintaining rice yield parity with double cropping.However,the prolonged growth duration of the rice ratooning system extends the exposure window to Magnaporthe oryzae infection,thereby elevating the probability of disease incidence.展开更多
Chemical fertilizers are a source of soil degradation. In order to mitigate soil degradation and to face the negative impacts of climate change, the use of organic fertilizers, accessible to small farmers can maintain...Chemical fertilizers are a source of soil degradation. In order to mitigate soil degradation and to face the negative impacts of climate change, the use of organic fertilizers, accessible to small farmers can maintain the productivity of cereals including rice. The objective of this experiment is to study the effect of organo-mineral fertilizers on soil chemical properties, growth and physiology parameters and yield of rice. For this purpose, a completely randomized block design with three replications was adopted. Different organic (Fertinova, Organova and Fertinova + Organova) and mineral (NPK + Urea) fertilizers were applied to cultivate the NERICA L19 variety of rice. The soil chemical properties (pH), germination rate, growth, yield and physiological (chlorophyll content) parameters were assessed. The results revealed a germination rate of the grains varying between 87.5 and 100%. Fertinova and Fertinova + Organova had the highest germination rates. Soil pH decreased significantly from initial (6.71 ± 0.01) to final (5.73 ± 0.04) with the development cycle of the rice. Organo-mineral fertilizers influenced significantly (p = 5.36e−09) soil chemical properties by increasing pH (4%) compared to Control. Analysis of variance on growth and yield parameters, yield and chlorophyll content revealed a significant difference (p < 0.05) between fertilizers. Growth and yield parameters and yield were significantly higher in NPK and Fertinova + Organova than in Fertinova, Organova and Control. For the biomass the NPK + Urea recorded significantly highest biomass (488.28 ± 60.83 g). Leaves chlorophyll content varied significantly according to the daytime and the status of leaf development. The higher chlorophyll content was recorded at noon (27.96 ± 0.32 SPAD value) and with young leaves (30.21 ± 0.35 SPAD value). NPK + Urea (29.36 ± 0.45 SPAD value) and Fertinova (27.78 ± 0.40 SPAD value) favored more chlorophyll content in the rice leaves. Rice performed better in NPK + Urea and Fertinova + Organova fertilizers.展开更多
Rice (Oryza sativa) is becoming a staplefood in many regions of DR-Congo. However, its production is still limited to the North Eastern part of the country and grain yield is low. A study was carried out in the city o...Rice (Oryza sativa) is becoming a staplefood in many regions of DR-Congo. However, its production is still limited to the North Eastern part of the country and grain yield is low. A study was carried out in the city of Mbujimayi located in the Central part of the DR-Congo to assess the effects of organic and inorganic fertilizers on morpho-agronomic characteristics of O. sativa. The trial was conducted during the 2021 agricultural season A using a completely randomized design with three replicates. The six treatments studied consisted of application of T. diversifolia biomass at a dose of 2 kg/4m2 (BFT − 2 kg), 4 kg/4 m2 (BFT − 4 kg), inorganic fertilizer consisting with NPK17-17-17 + Urea (46% N) at a combined dose of 80 g/4 m2 (NP), 1/2 of the combination (BFT − 2 kg + NP) and finally 1/2 of the combination (BFT − 4 kg + NP). The untreated plots were used as controls. Plants treated with 1/2 combination (BFT − 4 kg + NP), BFT – 4 kg, and NP showed similar height (100.93 cm, 99.03 cm, and 98.63 cm, respectively) that were significantly higher than control and other treatments [1/2 (BFT – 2 kg + NP, BFT – 2 kg] For agronomic characteristics, days to 50% flowering varied between 73.00 and 74 days with an average of 74 days. The control and BFT – 4 kg showed significantly shorter panicles compared to other treatments. For yield components, 1/2 (BFT – 4 kg + NP) and the NP treatments generated a higher weight of 1000 grains. For yield per hectare, 1/2 (BFT − 4 kg + NP) induced significantly different levels of production than the control and other treatments, including 1/2 (BFT – 2 kg + NP), BFT – 4 kg + NP, BFT – 2 kg, BFT – 4 kg. The correlation coefficients between agronomic traits revealed that with the exception of the length of particle and the abortion rates, all the yield components (panicles per plant, seeds per panicle, weight of 1000 grains, and grail yield per plot) were strongly correlated with grain yield per hectare.展开更多
Varietal deficiencies of upland rice lead to a low paddy grain yield. The aim of this study was to mutagenesis upland rice varieties to improve their agronomic performance. Seeds of varieties FKR45N and FKR47N were th...Varietal deficiencies of upland rice lead to a low paddy grain yield. The aim of this study was to mutagenesis upland rice varieties to improve their agronomic performance. Seeds of varieties FKR45N and FKR47N were therefore irradiated with doses 300, 350 and 400 Gy. The irradiated seeds were sown and the panicles of the M1 plants were individually harvested, and then were advanced to M4 using the “one panicle - one progeny” method. The agronomic performance of M4 lines was compared to that of their parent. The gamma ray mutagenesis has induced significant variability in five yield components, i.e., plant height, main panicle length, total numbers of tillers and productive tillers and paddy grain yield between mutant lines. The highest variabilities were shown for the total number of tillers and the number of productive tillers as well as FKR45N (CV% = 40 % and 36%) and FKR47N (CV% = 31% and 30%) mutant lines. Principal component analysis led to rank the mutant lines from each variety in three clusters. The Pearson correlation showed that the paddy grain yield was significantly and positively correlated with the number of productive tillers (r = 0.61) and plant height (r = 0.66) for FKR47N mutant lines, and these correlation coefficients were r = 0.52 and r = 0.51 for FKR45N mutant lines, respectively. Gamma-ray irradiation also induced an earliness of 50% flowering of 62 days after sowing (DAS) in two FKR45N mutant lines and 67 DAS in one of KR47N mutant lines. The paddy grain yield was improved by 120% and 20% in two FKR45N and FKR47N mutant lines, respectively. A dwarf FKR45N mutant line with an early flowering of 67 DAS and a paddy grain yield (2.34 t ha−1) was generated. These results suggested that any positive increase in the six quantitative traits will increase the paddy grain yield.展开更多
基金National Key Research and Development Project of China(2022yfd1500501)Jilin Province Science and Technology Department Outstanding Young Talent Fund Project(20230508001RC).
文摘The yield of direct-seeded rice(DSR)was constrained by inadequate grain filling.Recent studies have indicated that paclobutrazol application plays a significant role in enhancing crop agronomic traits and increasing yield.This study aimed to examine the effects of paclobutrazol seed soaking(PSS)on non-structural carbohydrate accumulation and grain enrichment in DSR,potentially providing a theoretical foundation for achieving high-yield DSR cultivation.The experiment utilized two rice varieties,Jiyujing(JYJ)and Jijing305(JJ305),with seeds soaked in paclobutrazol concentrations of 0 mg L^(−1) and 100 mg L^(−1).PSS demonstrated increased chlorophyll content,net photosynthetic rate,and leaf area,as well as an extended photosynthetic function period during the filling stage.It also elevated soluble sugar and starch contents in the flag leaf(during the filling stage)and stem sheath(after heading),decreased starch content in the top panicle while increasing it in the middle and lower panicle during the filling stage,and enhanced spikelet per unit area and seed setting rate,thereby improving DSR yield.In conclusion,PSS enhanced the photosynthetic capacity of DSR during the filling stage,coordinated the filling process of superior and inferior grains,maintained source-sink balance,and facilitated stable and orderly filling,ultimately resulting in improved yield.
基金Supported by National Natural Science Foundation of China(31371562,31301276)Special Fund for Fundamental Scientific Research Business of Central Public Research Institutes(Agriculture)(201103003+2 种基金201203079)Key Projects in the National Science&Technology Pillar Program during the 12thFive-year Plan Period(2012BAD04B08)Fund for Independent Innovation of Agricultural Sciences in Jiangsu Province(CX(14)5021)~~
文摘[Objective] This study aimed to investigate the effect of direct-seeding with non-flooding and wheat residue returning patterns on greenhouse gas emission from rice paddy. [Method] Two rice cultivars currently used in the production, Yangdao 6 （an indica） and Yangjing 4038 （a japonica）, were field grown using a direct-seeding method, and four treatments, wheat straw incorporation into soil and traditional flooding （SlF）, non-flooding and wheat straw mulching （NSM）, non-flooding and wheat straw incorporation into soil （NSl） and traditional flooding （no straw returned, Control, TF）, were imposed after sowing to maturity. Effects of direct-seeding with non-flooding and wheat residue returning patterns on CH4, N20 and CO2 emissions were investigated by using the method of static chamber-gas chromatographic tech- niques. [Result] Grain yield showed no significant difference between non-flooding and flooding treatments, but was significantly higher under the SlF than under any other treatments. The emission flux of CH4 and CO2 under TF and SlF exhibited a single peak curve, while changed little under the NSl and NSM The emission flux of N2Oshowed multiple perk curves for all the treatments. Compared with TF, SlF significantly increased mean emission flux of CH4 or N2O, decreased emission of N20, while NSl and NSM significantly decreased the mean emission flux of OH4, and increased emission flux of N2O and CO2. SIF also increased Green Warm Potential （GWP） of CH4, N2O and CO2 and the GWP per unit grain yield by 47.3%- 53.7% and 32.2%-39.4%, respectively. Both NSl and NSM decreased GWP by 24.2%-29.6% and 30.1%-35.5%, and the GWP per unit grain yield was decreased by 21.7-27.2% and 25.6%-31.1%, respectively. [Conelusion] both NSl and NSM could significantly reduce greenhouse effect of CH4, N2O and CO2 meanwhile maintain a high grain yield.
基金supported by the Indian Council of Agricultural Research-International Rice Research Institute Collaborative Project, India (Grant No. OXX4928)。
文摘The sustainability of rice production continues to be a subject of uncertainty and inquiry attributed to shifts in climatic conditions. In light of the impending climate change crisis and the high labor and water costs accompanying it, direct-seeded rice(DSR) is unquestionably one of the most practical solutions. Despite its resource and climate-friendly advantages, early maturing rice faces weed competitiveness and seedling establishment challenges. Resolving these issues is crucial for promoting its wider adoption among farmers, presenting it as a more effective sustainable rice cultivation method globally. Diverse traditional and contemporary breeding methods are employed to mitigate the limitations of the DSR approach, leveraging advanced techniques such as speed breeding and genome editing. Focusing on key traits like mesocotyl length elongation, early seedling vigor, root system architecture, and weed competitiveness holds promise for transformative improvements in DSR adaptation at a broader scale within farming communities. This review aims to summarize how these features contribute to increased crop production in DSR conditions and explore the research efforts focusing on enhancing DSR adaptation through these traits. Emphasizing the pivotal role of these game-changing traits in DSR adaptation, our analysis sheds light on their potential transformative impact and offers valuable insights for advancing DSR practices.
基金supported by the National Key Research and Development Program of China(No.2016YFD0100101-19)the Rice Industry Technology System of Henan Province(No.S2012-04)the Independent Innovation Fund Program of Henan Academy of Agricultural Sciences(No.2020ZC07)。
文摘Mesocotyl elongation is a key trait influencing seedling emergence and establishment in direct-seeding rice cultivation.The phytohormone gibberellin(GA)has positive effects on mesocotyl elongation in rice.However,the physiological and molecular basis underlying the regulation of mesocotyl elongation mediated by GA priming under deep-sowing conditions remains largely unclear.In the present study,we performed a physiological and comprehensive transcriptomic analysis of the function of GA priming in mesocotyl elongation and seedling emergence using a direct-seeding japonica rice cultivar ZH10 at a5-cm sowing depth.Physiological experiments indicated that GA priming significantly improved rice seedling emergence by increasing the activity of starch-metabolizing enzymes and compatible solute content to supply the energy essential for subsequent development.Transcriptomic analysis revealed 7074 differentially expressed genes(false discovery rate of<0.05,|log2(fold change)|of≥1)after GA priming.Furthermore,gene ontology(GO)and Kyoto encyclopedia of genes and genomes(KEGG)enrichment analyses revealed that genes associated with transcriptional regulation,plant hormone biosynthesis or signaling,and starch and sucrose metabolism were critical for GA-mediated promotion of rice mesocotyl elongation.Further analyses showed that the expression of the transcription factor(TF)genes(v-myb avian myeloblastosis viral oncogene homolog(MYB)alternative splicing 1(MYBAS1),phytochrome-interacting factors 1(PIF1),Oryza sativa teosinte branched 1/cycloidea/proliferating cell factor 5(Os TCP5),slender 1(SLN1),and mini zinc finger 1(MIF1)),plant hormone biosynthesis or signaling genes(brassinazole-resistant 1(BZR1),ent-kaurenoic acid oxidase-like(KAO),GRETCHEN HAGEN 3.2(GH3.2),and small auxin up RNA 36(SAUR36)),and starch and sucrose metabolism genes(α-amylases(AMY2 A and AMY1.4))was highly correlated with the mesocotyl elongation and deep-sowing tolerance response.These results enhance our understanding of how nutrient metabolism-related substances and genes regulate rice mesocotyl elongation.This may facilitate future studies on related genes and the development of novel rice varieties tolerant to deep sowing.
基金supported by the National Key Research and Development Program of China (Grant No.2019YFE0197100)the Agricultural Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences。
文摘Rice direct seeding technology is an appealing alternative to traditional transplanting because it conserves labor and irrigation resources.Nevertheless,there are two main issues,salt stress and alkaline stress,which contribute to poor emergence and seedling growth,thereby preventing the widespread adoption and application of this technique in the Ningxia Region of China.Therefore,to determine whether germination can be promoted by mixed-oligosaccharide(KP)priming(in which seeds are soaked in a KP solution before sowing)under salt and alkaline stress,a proteomics study was performed.KP-priming significantly mitigated abiotic stress,such as salt and alkaline stress,by inhibiting root elongation,ultimately improving seedling establishment.By comparing the proteomics analyses,we found that energy metabolic pathway was a vital factor in KP-priming,which explains the alleviation of salt and alkaline stress.Key proteins involved in starch mobilization,pyruvate mobilization,and ATP synthesis,were up-regulated by KP-priming,significantly blocking salt and alkaline-triggered starch accumulation while enhancing pyruvate metabolism.KP-priming also up-regulated ATP synthase to improve energy efficiency,thereby improving ATP production.In addition,it enhanced antioxidant enzymatic activities and reduced the accumulation of reactive oxygen species.All of these factors contributed to a better understanding of the energy regulatory pathway enhanced by KP-priming,which mediated the promotion of growth under salt and alkaline conditions.Thus,this study demonstrated that KP-priming can improve rice seed germination under salt and alkaline stress by altering energy metabolism.
基金supported by Science and Technology Innovation Program of Hunan province(2024NK1010,2023NK1010,2023ZJ1080)the National Natural Science Foundation of China(U21A20208).
文摘The chalcone isomerase gene OsCHI,one of the key genes in the flavonoid biosynthesis pathway,plays an important role in rice(Oryza sativa)resistance to abiotic stresses.This study reveals how the chalcone isomerase gene family member OsCHI3 participates in rice responses to drought stress through the regulation of flavonoid biosynthesis.Overexpression of OsCHI3 increased the tolerance of rice to drought stress.In contrast,CRISPR/Cas9-mediated deletion of OsCHI3 reduced the drought tolerance of rice,an effect that is reversed by exogenous ABA treatment.Transcriptomic and physiological biochemical analyses indicated that flavonoids regulated by OsCHI3 not only scavenge reactive oxygen species(ROS)but also increase drought tolerance in rice by stimulating ABA biosynthesis through the regulation of OsNCED1 and OsABA8ox3 expression.These findings demonstrate that OsCHI3 increases drought stress tolerance in rice by activating the antioxidant defense system and the ABA metabolic pathway,providing new clues for drought-resistant rice breeding research.
基金supported by the National Natural Science Foundation of China(32172059)Fundamental Research Funds for the Central Universities(SWUXDJH202315).
文摘Pre-harvest sprouting(PHS)describes the germination of physiologically mature grains in spikes prior to harvest in cereal crops.PHS could seriously decrease grain yield and quality,which makes it a major constraint to cereal production worldwide.A number of PHS-associated genes in cereals have been reported;however,the molecular mechanisms underlying PHS remain largely elusive.Here,we report a CRISPRCas9 mutant with severe PHS in a paddy field.The mutated gene OsMFT2 encodes a phosphatidylethanolamine-binding protein(PEBP).Intriguingly,the OsMFT1,in the same PEBP family,had the opposite effect in controlling rice PHS as does OsMFT2.Germination tests of seeds of chimeric protein-expressing plants revealed that the fourth exon conferred the antagonistic activity of OsMFT1 and OsMFT2 in rice PHS.Additionally,two lines of these plants showed elevated grain numbers per panicle,implying that chimeric protein has potential to significantly increase yield.Moreover,transcriptome analysis and genetic studies indicated that OsMFT1 and OsMFT2 performed opposing functions in rice PHS owing to three co-regulated genes that being contrastingly affected by OsMFT1 and OsMFT2.Overall,it seemed that the proper combination of PEBP family members could obtain optimal PHS resistance and high yield.
基金funded by the National Key Research and Development Plan of China(2023YFD1400300)National Natural Science Foundation of China(U23A6006,32270149,32272555)+1 种基金Zhejiang Provincial Natural Science Foundation(LZ22C140001)the Ningbo Major Research and Development Plan Project(2023Z124).
文摘Viruses are significant pathogens causing severe plant infections and crop losses globally.The resistance mechanisms of rice to viral diseases,particularly Southern rice black-streaked dwarf virus(SRBSDV),remain poorly understood.In this study,we assessed SRBSDV susceptibility in 20 Xian/indica(XI)and 20 Geng/japonica(GJ)rice varieties.XI-1B accessions in the Xian subgroup displayed higher resistance than GJ accessions.Comparative transcriptome analysis revealed changes in processes like oxidoreductase activity,jasmonic acid(JA)metabolism,and stress response.JA sensitivity assays further linked antiviral defense to the JA pathway.These findings highlight a JA-mediated resistance mechanism in rice and offer insights for breeding SRBSDV-resistant varieties.
基金funded by grants from the National Natural Science Foundation of China (31930006 to Y.W.)the National Key Research and Development Program of China (2022YFF1002903 to Y.W.)+1 种基金the Top Talents Program “One Case One Discussion”(Yishiyiyi to Y.W.)from Shandong provinceShandong Agricultural University Talent Introduction Start-up Fund (to N.Z.)
文摘Branching is a critical aspect of plant architecture that significantly impacts the yield and adaptability of staple cereal crops like rice and wheat.Cereal crops develop tillers during the vegetative stage and panicle or spike branches during the reproductive stage,respectively,both of which are significantly impacted by hormones and genetic factors.Tillering and panicle branching are closely interconnected and exhibit high environmental plasticity.Here,we summarize the recent progress in genetic,hormonal,and environmental factors regulation in the branching of rice and wheat.This review not only provides a comprehensive overview of the current knowledge on branching mechanisms in rice and wheat,but also explores the prospects for future research aimed at optimizing crop architecture for enhanced productivity.
基金supported by grants from the National Natural Science Foundation of China(32072403 and 31871945)the National Key Research and Development Program of China(2016YFD0100600).
文摘The RING-type E3 ligase OsBBI1 regulates rice resistance against Magnaporthe oryzae through modifying cell wall defenses.In this study,we report the function of an OsBBI1 substrate,eukaryotic translation initiation factor OseIF5A4,in rice immunity.OsBBI1 interacts with OseIF5A4 and other four members of the OseIF5A family.The RING domain in OsBBI1 and the eIF-5a domain in OseIF5A4 are critical for the OsBBI1-OseIF5A4 interaction.OsBBI1 ubiquitinates OseIF5A4 and mediates its degradation in vitro and in vivo.Moreover,the expression of OseIF5A4 was upregulated during early stage of compatible interaction but downregulated in incompatible interaction between rice and M.oryzae.Knockout of OseIF5A4 enhances rice immunity against M.oryzae and Xanthomonas oryzae pv.oryzae,boosts pattern-triggered immune responses,and strengthens pathogen-induced defense responses(e.g.,expression of defense genes,accumulation of reactive oxygen species and reinforcement of cell wall).However,overexpression of OseIF5A4 attenuates rice immunity and immune responses.These results demonstrate that OseIF5A4,a substrate of the immunity-associated E3 ligase OsBBI1,negatively regulates rice immunity against M.oryzae and X.oryzae pv.oryzae through modulating pathogen-induced defense responses,highlighting the importance of the protein translational machinery in rice immunity.
基金supported by Research Program for Agricultural Science and Technology Development,Republic of Korea(PJ01570601)the Fellowship Program(PJ01661001)of the National Institute of Agricultural Sciences,Republic of KoreaRural Development Administration,Republic of Korea.
文摘The emergence of novel phytopathogens and the accelerated spread of plant diseases to new regions,driven by global climate change,constitute significant threats to agricultural resources.Rice,a major tropical staple crucial for global food security,possesses six transcription factor superfamilies-AP2/ERF,bHLH,bZIP,MYB,NAC,and WRKY-that function in innate immunity against pathogens.We review their biological functions and regulatory mechanisms in rice immunity.
基金supported by the Science and Technology Innovation Program of Hunan Province(2022RC1148)the Natural Science Foundation of Hunan Province(2022JJ31009,2022JJ50260)+4 种基金the Program for Science and Technology of Changsha,China(kh2301028)the Science and Technology Innovation Plan Project of Hunan Province(2023NK2033)the Innovation Leading Plan Project of Hunan Province(2021GK4022)the“Kemen Food”Graduate Science and Technology Innovation Project of Central South University of Forestry and Technology(2023KMCX02)the Graduate Science and Technology Innovation Fund Project of Hunan Province(QL20220182).
文摘Alzheimer’s disease(AD)is a neurodegenerative disorder associated with brain aging,and the accumulation ofβ-amyloid(Aβ)and hyperphosphorylated Tau proteins are key pathological features.Currently,drugs for the treatment of AD are mainly single-targeted,but the complex pathogenesis of AD makes it difficult to achieve the desired results.Therefore,the development of multitargeted therapies is crucial for future interventions.Rice bran oil(RBO)has been recognized as an edible oil with several health benefits,but its effects on AD caused by brain aging remain underexplored.In this study,the effects of RBO on memory dysfunction in D-galactose(D-gal)mice and its molecular mechanisms were investigated via in vivo and in silico methods from the perspective of AD pathologies.Our results suggested that compounds in RBO could modulate the activities of Aβprecursor protein cleaving enzyme 1(BACE1),mitogen-activated protein kinase 3(MAPK3),matrix metalloproteinase 3(MMP3),and intercellular adhesion molecule 1(ICAM1),leading to inhibition of Aβaccumulation and Tau protein hyperphosphorylation.Moreover,RBO reduced Aβ-induced oxidative stress by inhibiting the activity of mouse double minute 2 homolog(MDM2)and cyclic adenosine monophosphate(cAMP)response element binding protein binding protein(CREBBP),and attenuated neuroinflammation by inhibiting the activity of nitric oxide synthase 2(NOS2)and reducing Aβaccumulation and Tau protein hyperphosphorylation.Additionally,α-linolenic acid in RBO exhibited inhibitory effects on D-gal-induced apoptosis in PC12 cells through modulation of NOS2,MDM2,ICAM1,and phospho-extracellular signal-regulated kinase 1/2(p-ERK1/2).Similarly,stigmastanol inhibited apoptosis in D-gal-induced PC12 cells through the regulation of NOS2.Thus,RBO can be considered as a potential functional food to attenuate AD owing to its multicomponent and multitarget effects.
基金supported by the Sichuan Province International Science and Technology Innovation Cooperation(2024YFHZ0299)the Project of Science and Technology Department of Sichuan Province(2022YFH0031)Chengdu Science and Technology Bureau(2024-YF05-02168-SN).
文摘Rice sheath blight(RSB)is a major destructive disease impeding rice production.Identifying key germplasm resources with increased resistance remains a challenge.However,the mechanisms underlying disease resistance are not yet fully understood.Cytochrome P450 monooxygenases(CYP450s)serve biosynthesis and metabolic detoxification functions in plants,but there is limited information about their role in the response induced by RSB.This study demonstrated that CYT02 belongs to the CYP73A100 subfamily and is a typical member of the CYP450s.Overexpression(OE)in rice of the cytochrome P450 monooxygenase cyt02 conferred increased resistance to RSB and increased vegetative tillering.Cyt02 may increase RSB resistance by regulating plant hormone synthesis,regulate reactive oxygen species(ROS)by coordinating the activity of antioxidant enzymes,and initiate phytoalexin synthesis in response to fungal infection.These research findings have laid a foundation for a deeper understanding of the function of cyt02 and offered a potential target gene for breeding rice varieties resistant to sheath blight.
基金funded by the Jiangsu Key Research Program,China(BE2022338)the Jiangsu Agricultural Science and Technology Innovation Fund,China(CX(23)3107)+3 种基金the Natural Science Foundation of the Jiangsu Higher Education Institutions,China(22KJB210004)the Jiangsu Province Agricultural Major Technology Collaborative Promotion Project,China(2022-ZYXT-04-1)the Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(KYCX23_3569)the Priority Academic Program Development of Jiangsu Higher Education Institutions,China.
文摘The high labor demand during rice seedling cultivation and transplantation poses a significant challenge in advancing machine-transplanted rice cultivation.This problem may be solved by increasing the seeding rate during seedling production while reducing the number of seedling trays.This study conducted field experiments from 2021 to 2022,using transplanting seedling ages of 10 and 15 days to explore the effects of 250,300,and 350 g/tray on the seedling quality,mechanical transplantation quality,yields,and economic benefits of rice.The commonly used combination of 150 g/tray with a 20-day seedling age in rice production was used as CK.The cultivation of seedlings under a high seeding rate and short seedling age significantly affected seedling characteristics,but there was no significant difference in seedling vitality compared to CK.The minimum number of rice trays used in the experiment was observed in the treatment of 350-10(300 g/tray and 10-day seedling age),only 152-155 trays ha^(-1),resulting in a 62%reduction in the number of trays needed.By increasing the seeding rate of rice,missed holes during mechanical transplantation decreased by 2.8 to 4%.The treatment of 300-15(300 g/tray and 15-day seedling age)achieved the highest yields and economic gains.These results indicated that using crop straw boards can reduce the application of seedling trays.On that basis,rice yields can be increased by raising the seeding rate and shortening the seedling age of rice without compromising seedling quality.
基金supported by a sub-award to the University of Missouri from the Heinrich Heine University of Dusseldorf funded by the Bill&Melinda Gates Foundation(OPP1155704)(Bing Yang)and the China Scholar Council(Chenhao Li,as a joint Ph.D.student).
文摘Bacterial blight(BB),caused by Xanthomonas oryzae pathovar oryzae(Xoo),poses a significant threat to rice production,particularly in Asia and West Africa.Breeding resistance against BB in elite rice varieties is crucial to advancing rice breeding program and supporting smallholder farmers.Transcription Activator-Like effectors(TALes)are key virulence factors in Xoo,with some targeting the susceptibility(S)genes such as the sugar transporter SWEET genes in rice.Among these,SWEET14 is an important S gene,with its promoter bound by the TALe TalC which exists across all sequenced African Xoo isolates.In the present study,we utilized CRISPR/Cas9-based cytidine and adenine base editors to alter the effector binding element(EBE)of TalC in the promoter of SWEET14 in rice cultivars Kitaake,IR24,and Zhonghua 11.Mutations with C to T changes in EBE led to reduced SWEET14 induction by TalC-containing Xoo strains,resulting in resistance to African Xoo isolates reliant on TalC for virulence.Conversely,A to G changes retained SWEET14 inducibility and susceptibility to Xoo in edited lines.Importantly,no off-target mutations were detected at predicted sites,and the edited lines exhibited no obvious defects in major agronomic traits in Kitaake.These results underscore the effectiveness of base editing systems for both molecular biology research and crop improvement endeavors.
基金supported by the Key Research and Development Program Project of Hunan Province, China (Grant No. 2023NK2003)the National Key Research and Development Program of China (Grant No. 2022YFD2301001-03)the National Key Research and Development Program of China (Grant No. 2022YFD2301003)
文摘The ratooning system enhances agricultural efficiency by reducing secondary sowing and resource input while maintaining rice yield parity with double cropping.However,the prolonged growth duration of the rice ratooning system extends the exposure window to Magnaporthe oryzae infection,thereby elevating the probability of disease incidence.
文摘Chemical fertilizers are a source of soil degradation. In order to mitigate soil degradation and to face the negative impacts of climate change, the use of organic fertilizers, accessible to small farmers can maintain the productivity of cereals including rice. The objective of this experiment is to study the effect of organo-mineral fertilizers on soil chemical properties, growth and physiology parameters and yield of rice. For this purpose, a completely randomized block design with three replications was adopted. Different organic (Fertinova, Organova and Fertinova + Organova) and mineral (NPK + Urea) fertilizers were applied to cultivate the NERICA L19 variety of rice. The soil chemical properties (pH), germination rate, growth, yield and physiological (chlorophyll content) parameters were assessed. The results revealed a germination rate of the grains varying between 87.5 and 100%. Fertinova and Fertinova + Organova had the highest germination rates. Soil pH decreased significantly from initial (6.71 ± 0.01) to final (5.73 ± 0.04) with the development cycle of the rice. Organo-mineral fertilizers influenced significantly (p = 5.36e−09) soil chemical properties by increasing pH (4%) compared to Control. Analysis of variance on growth and yield parameters, yield and chlorophyll content revealed a significant difference (p < 0.05) between fertilizers. Growth and yield parameters and yield were significantly higher in NPK and Fertinova + Organova than in Fertinova, Organova and Control. For the biomass the NPK + Urea recorded significantly highest biomass (488.28 ± 60.83 g). Leaves chlorophyll content varied significantly according to the daytime and the status of leaf development. The higher chlorophyll content was recorded at noon (27.96 ± 0.32 SPAD value) and with young leaves (30.21 ± 0.35 SPAD value). NPK + Urea (29.36 ± 0.45 SPAD value) and Fertinova (27.78 ± 0.40 SPAD value) favored more chlorophyll content in the rice leaves. Rice performed better in NPK + Urea and Fertinova + Organova fertilizers.
文摘Rice (Oryza sativa) is becoming a staplefood in many regions of DR-Congo. However, its production is still limited to the North Eastern part of the country and grain yield is low. A study was carried out in the city of Mbujimayi located in the Central part of the DR-Congo to assess the effects of organic and inorganic fertilizers on morpho-agronomic characteristics of O. sativa. The trial was conducted during the 2021 agricultural season A using a completely randomized design with three replicates. The six treatments studied consisted of application of T. diversifolia biomass at a dose of 2 kg/4m2 (BFT − 2 kg), 4 kg/4 m2 (BFT − 4 kg), inorganic fertilizer consisting with NPK17-17-17 + Urea (46% N) at a combined dose of 80 g/4 m2 (NP), 1/2 of the combination (BFT − 2 kg + NP) and finally 1/2 of the combination (BFT − 4 kg + NP). The untreated plots were used as controls. Plants treated with 1/2 combination (BFT − 4 kg + NP), BFT – 4 kg, and NP showed similar height (100.93 cm, 99.03 cm, and 98.63 cm, respectively) that were significantly higher than control and other treatments [1/2 (BFT – 2 kg + NP, BFT – 2 kg] For agronomic characteristics, days to 50% flowering varied between 73.00 and 74 days with an average of 74 days. The control and BFT – 4 kg showed significantly shorter panicles compared to other treatments. For yield components, 1/2 (BFT – 4 kg + NP) and the NP treatments generated a higher weight of 1000 grains. For yield per hectare, 1/2 (BFT − 4 kg + NP) induced significantly different levels of production than the control and other treatments, including 1/2 (BFT – 2 kg + NP), BFT – 4 kg + NP, BFT – 2 kg, BFT – 4 kg. The correlation coefficients between agronomic traits revealed that with the exception of the length of particle and the abortion rates, all the yield components (panicles per plant, seeds per panicle, weight of 1000 grains, and grail yield per plot) were strongly correlated with grain yield per hectare.
文摘Varietal deficiencies of upland rice lead to a low paddy grain yield. The aim of this study was to mutagenesis upland rice varieties to improve their agronomic performance. Seeds of varieties FKR45N and FKR47N were therefore irradiated with doses 300, 350 and 400 Gy. The irradiated seeds were sown and the panicles of the M1 plants were individually harvested, and then were advanced to M4 using the “one panicle - one progeny” method. The agronomic performance of M4 lines was compared to that of their parent. The gamma ray mutagenesis has induced significant variability in five yield components, i.e., plant height, main panicle length, total numbers of tillers and productive tillers and paddy grain yield between mutant lines. The highest variabilities were shown for the total number of tillers and the number of productive tillers as well as FKR45N (CV% = 40 % and 36%) and FKR47N (CV% = 31% and 30%) mutant lines. Principal component analysis led to rank the mutant lines from each variety in three clusters. The Pearson correlation showed that the paddy grain yield was significantly and positively correlated with the number of productive tillers (r = 0.61) and plant height (r = 0.66) for FKR47N mutant lines, and these correlation coefficients were r = 0.52 and r = 0.51 for FKR45N mutant lines, respectively. Gamma-ray irradiation also induced an earliness of 50% flowering of 62 days after sowing (DAS) in two FKR45N mutant lines and 67 DAS in one of KR47N mutant lines. The paddy grain yield was improved by 120% and 20% in two FKR45N and FKR47N mutant lines, respectively. A dwarf FKR45N mutant line with an early flowering of 67 DAS and a paddy grain yield (2.34 t ha−1) was generated. These results suggested that any positive increase in the six quantitative traits will increase the paddy grain yield.
