Field Crops Research最新文献

{"title":"Deficit irrigation combined with a high planting density optimizes root and soil water–nitrogen distribution to enhance cotton productivity in arid regions","authors":"","doi":"10.1016/j.fcr.2024.109524","DOIUrl":"10.1016/j.fcr.2024.109524","url":null,"abstract":"<div><h3>Context</h3><p>Increasing the cotton planting density can reduce irrigation while maintaining the seed cotton yield. However, the underlying physiological and ecological mechanisms remain unclear. We hypothesized that increasing the planting density and reducing irrigation would promote dynamic consistency in the distribution of the roots, soil water, and nitrogen, leading to improved cotton water productivity and ultimately achieving a stable seed cotton yield.</p></div><div><h3>Method</h3><p>To test this hypothesis, a 3-year field experiment (2019–2021) was conducted in Xinjiang, China. The main plots were subjected to 3 irrigation levels based on crop evapotranspiration (ETc): 0.6 (deficit), 0.8 (typical), and 1.0 ETc (adequate). Subplots were planted at 3 densities: 13.5 (low), 18.0 (typical), and 22.5 plants m⁻² (high).</p></div><div><h3>Results</h3><p>Under typical irrigation conditions, the seed cotton yield was significantly higher at a typical planting density than at a low or high planting density. However, with adequate irrigation, a low planting density resulted in a higher yield, while a high planting density combined with adequate irrigation reduced the yield by 14.7 % compared with typical conditions (typical irrigation + typical planting density). Under deficit irrigation, the seed cotton yield at a high planting density was 9.2–23.5 % higher than that at a low or typical planting density, achieving yield stability with 20 % water saving. The dry matter accumulation and harvest index showed no significant differences between typical irrigation + typical planting density and deficit irrigation + high planting density. Deficit irrigation combined with a high planting density resulted in a higher overlap rate of the root distribution area, soil water consumption area, and nitrate nitrogen consumption area, leading to higher water productivity than that of other density and irrigation combinations.</p></div><div><h3>Conclusion</h3><p>Deficit irrigation combined with a high planting density can reduce water input by 20 % without sacrificing cotton yield, likely because of increased water productivity through the enhanced dynamic consistency of root distribution and soil water-nitrogen consumption. These findings provide valuable ecological and physiological insights for achieving water savings without compromising yield in arid and water-scarce regions.</p></div>","PeriodicalId":12143,"journal":{"name":"Field Crops Research","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141979029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comprehensive growth monitoring index using Sentinel-2A data for large-scale cotton production","authors":"","doi":"10.1016/j.fcr.2024.109525","DOIUrl":"10.1016/j.fcr.2024.109525","url":null,"abstract":"<div><h3>Problem</h3><p>Timely and accurate plant growth monitoring is crucial for precision crop management. Traditional remote sensing methods use a single agronomic parameter to evaluate crop growth status (GST), limiting accuracy.</p></div><div><h3>Objective</h3><p>To develop a comprehensive growth monitoring index (CGMI) based on multiple parameters.</p></div><div><h3>Methods</h3><p>A two-year field experiment in the Mosuwan Reclamation Region of Xinjiang, China was conducted to collect parameter characterization data for cotton growth, including leaf area index, canopy chlorophyll content, above-ground biomass, and boll numbers, and their contributions and interrelationships in relation to yield were analyzed. Entropy and game theory weighting methods were used to establish the CGMI_EWM and CGMI_GT, and a sequential forward selection algorithm (SFS) was used to screen the most effective remote-sensing monitoring feature variables for the different reproductive stages. Partial least squares regression (PLSR), random forest (RF), and support vector regression (SVR) were used to develop an optimal model to comprehensively monitor cotton growth and draw a spatial distribution map.</p></div><div><h3>Results</h3><p>CGMI_EWM and CGMI_GT could effectively reflect GST. The correlation between CGMI_GT and yield based on a game theory combination weighting method was significantly higher than that between yield and each agronomic parameter. The correlation between CGMI_GT and yield (r = 0.75) was slightly higher at the initial boll stage than that of CGMI_EWM (r = 0.73), whereas at the initial boll-opening stage, the correlation between CGMIGT and yield (r = 0.74) was significantly higher than that of CGMI_EWM (r = 0.63). The weight coefficients used to construct the CGMI_GT exhibited stable performance in different years. Feature variables were selected to monitor the comprehensive growth of cotton at different stages based on the SFS algorithm. PLSR, RF, and SVR were used to estimate CGMI_GT. The RF algorithm had the best estimation performance in both the initial boll and initial boll-opening stages (R² = 0.63, root mean square error (RMSE) = 0.086, RE = 19.8 % vs. R² = 0.56, RMSE = 0.107, RE = 24.1 %). A comprehensive cotton growth distribution map in the Mosuwan Reclamation Region was drawn using the optimal model, and growth was comprehensively evaluated. Areas with good cotton growth were concentrated in the north, and there was a decreasing trend from north to south.</p></div><div><h3>Conclusions</h3><p>We provide a new comprehensive evaluation tool for cotton growth status large-scale, real-time monitoring.</p></div><div><h3>Significance</h3><p>Our results promote differentiated management, improve crop yield prediction accuracy, and aid in the formulation of cotton price strategies.</p></div>","PeriodicalId":12143,"journal":{"name":"Field Crops Research","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141915331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ecological factors regulate stalk lodging within dense planting maize","authors":"","doi":"10.1016/j.fcr.2024.109529","DOIUrl":"10.1016/j.fcr.2024.109529","url":null,"abstract":"<div><h3>Context</h3><p>Ecological factors affect maize growth and development, and induce stalk lodging. Studying the effects of ecological factors on the stalk lodging within dense planting maize is essential to develop field management strategies.</p></div><div><h3>Objective</h3><p>To investigate the response of stalk lodging resistance to density and ecological site. To identify the key ecological factors affecting lodging.</p></div><div><h3>Methods</h3><p>This study conducted field experiments in 2019–2020 at 6 sites in Southwest China, with 6 densities (3.0, 4.5, 6.0, 7.5, 9.0 and 10.5 × 10⁴ plants hm⁻²) to determine the variation in lodging rate and stalk lodging resistance traits.</p></div><div><h3>Results</h3><p>The dense planting reduced stalk lodging resistance and varied among ecological sites. Plant morphology exhibited relatively high stability, with coefficients of variation (CV) of 0.01143–0.1097. Bending strength and dry matter constituents of basal internodes were more sensitive (CV: 0.1425–0.4446) compared to other traits, while the density effect was more significant. The extreme weather and stalk lodging resistance index jointly determined lodging, with lodging lowest at high stalk lodging resistance index (≥1.367) and low frequency of extreme weather events (＜14.40 %). Among the internode traits, the dry matter constituents contributed more than 55.0 % to mechanical strength. In addition, internode diameter was important for bending strength, while skin group was for rind penetration strength. Altitude or net solar radiation explained 28.70 % or 21.10 % of the mechanical strength, being the most important ecological factor.</p></div><div><h3>Conclusions</h3><p>Maize stalk lodging resistance decreased with dense planting and also influenced by ecological factors, but the response of different stalk lodging resistance traits to density and ecological site. The higher altitude and net solar radiation favored higher internode mechanical strength, resulting in greater stalk lodging resistance. The lower frequency of extreme weather events and higher stalk lodging resistance index resulted in a lower lodging rate.</p></div><div><h3>Implications</h3><p>The selection of maize hybrids with high internode plumpness, cellulose and lignin content in the basal internodes and less affected by density and ecological sites, can enhance stalk lodging resistance and its stability. The appropriate planting density should match the ecological conditions of the site.</p></div>","PeriodicalId":12143,"journal":{"name":"Field Crops Research","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141915328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Precision nutrient management influences the productivity, nutrients use efficiency, N2O fluxes and soil enzymatic activity in zero-till wheat (Triticum aestivum L.)","authors":"","doi":"10.1016/j.fcr.2024.109526","DOIUrl":"10.1016/j.fcr.2024.109526","url":null,"abstract":"<div><p>The concomitant quandaries of pedospheric health deterioration and diminishing factor productivity constitute the preeminent apprehensions within the realms of crop cultivation, particularly in the densely populated South Asian region. Conventional tillage practices, coupled with indiscriminate fertilizer application in wheat-based rotations, precipitate the degradation of natural resource bases, thereby posing an ominous threat to the rice-wheat cropping system (RWCS) prevalent in the Indo-Gangetic plains (IGP). Nonetheless, the adoption of zero-tillage (ZT) techniques, co-implemented with the judicious dispensation of nutrients through precision nutrient management (PNM), holds the potential to mitigate nutrient losses, curtail environmental ramifications, and augment the overall sustainability of wheat cultivation within the RWCS paradigm. Hence, efforts were made to investigate the impact of PNM on productivity, use efficiency of nutrients (N_tUE), root morphology, soil enzymatic activities, and the N₂O fluxes in ZT-wheat (ZT-W). The treatments were soil test-based NPK (STB-NPK), Nutrients Expert (NE)-based NPK [NE-(LCC_N) NPK], recommended doses of fertilizer (RDF), state recommendation-based NPK, and their nutrients omission treatments, together with consisted of twelve treatments. The result revealed that the PNM practices, like Nutrient Expert + Leaf colour chart (LCC)based NPK[NE-(LCC_N) NPK] co-implemented with ZT significantly (p&lt;0.05) improved the grain yield by (8.05 %), and nutrient use efficiency (NUE) by 58.1 %) but STB-NPK produce ∼ 17.1 % higher grain yield than the RDF. The application of balanced nutrients in ZT-wheat using NE-(LCC_N) NPK reduced the cumulative seasonal N₂O emission by 19.5 % over RDF, whereas, STB-NPK increased the N₂O emission by 26.2 % over RDF, due to the substantial application of N-fertilizer. Similarly, the root length density (RLD), root surface area density (RSAD) and root volume density (RVD) of wheat were found greater under STB-NPK and NE-(LCC_N) NPK than the RDF. Furthermore, the soil enzymatic activity was considerably enhanced due to PNM in the ZT-wheat system compared to the remaining treatments. The STB-NPK, and NE-(LCC_N) NPK, also improved the crop yield, and photo-synthetically active radiation (PAR) through greater leaf area index (LAI) besides other soil-based parameters of wheat. The NE-(LCC_N) NPK notably improves N_tUE, and minimises the GHGs emission than the others. Hence, the nutrient applied through NE-(LCC_N) NPK could enhance the yields, soil properties, and nutrient use efficiencies besides reducing GHGs emissions, thereby, sustaining cereal-based system in the long run.</p></div>","PeriodicalId":12143,"journal":{"name":"Field Crops Research","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141915330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simultaneous enhancement of maize yield and lodging resistance via delaying plant growth retardant application","authors":"","doi":"10.1016/j.fcr.2024.109530","DOIUrl":"10.1016/j.fcr.2024.109530","url":null,"abstract":"<div><h3>Context</h3><p>Plant growth retardants (PGRs) have been widely used to improve lodging resistance in crops like maize. However, unsuitable PGRs concentration and application stage always caused yield penalty.</p></div><div><h3>Objectives</h3><p>This study delayed PGR application time and increased the PGR concentration to simultaneously enhance lodging resistance and grain yield. We aimed to propose a model for maize production regulation and dwarf breeding.</p></div><div><h3>Methods</h3><p>A four-year field experiment was conducted by applying EC (a mixture of ethephon and cycocel) at V7 (7th leaf collar is visible; TV7) and V14 (TV14) stage, respectively. Lodging resistance, leaf area, florets, internode length, carbon isotope distribution, and grain yield were evaluated.</p></div><div><h3>Results</h3><p>The results showed that both TV7 and TV14 significantly improved stalk bending strength and lodging-resistant index compared to the control (CK). TV7 reduced basal internodes length and leaves area, while TV14 shortened the internodes above ear without affecting leaf size. Notably, the decreased stem in TV14 facilitated assimilates allocation to the ear from the leaves above ear traced by ¹³C isotope, which could promote kernel set when the number of fully developed florets of each treatment was similar. Indeed, the kernel number per ear was increased by 7.6 % for TV14 but reduced by 7.3 % for TV7 compared to CK, leading to a yield increase of 8.1 % for TV14 and a decrease of 8.1 % for TV7.</p></div><div><h3>Conclusion</h3><p>Hence, delaying the application of EC from V7 to V14 stage can effectively enhance both maize lodging resistance and grain yield. Finally, a model for optimizing the utilization of assimilates by PGRs is proposed, which provides an insight for maize production regulation and dwarf breeding in the future.</p></div>","PeriodicalId":12143,"journal":{"name":"Field Crops Research","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141915332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimal drip irrigation leaching amount and times enhance seed cotton yield and its stability by improving soil chemical environment and source-sink relationship","authors":"","doi":"10.1016/j.fcr.2024.109531","DOIUrl":"10.1016/j.fcr.2024.109531","url":null,"abstract":"<div><h3>Context</h3><p>The arid and semi-arid regions of northwest China play a pivotal role in the national cotton production. However, soil salinization poses a severe constraint on seed cotton yield in this region. Salt leaching by drip irrigation has become increasingly popular for ameliorating saline-alkali soils. Yet, the most effective approach for utilizing drip irrigation leaching to maximize cotton productivity remains uncertain.</p></div><div><h3>Methods</h3><p>Over a three-year period, field experiments were performed to explore the effects of four leaching amounts (75, 150, 225, and 300 mm) and four leaching times (seedling stage, budding stage, flowering stage, and boll-setting stage as one, two, three and four times) on soil-water dynamics, ion composition, source-sink relationships, seed cotton yield and its stability in saline-alkali cotton fields under drip irrigation.</p></div><div><h3>Results</h3><p>The study revealed that soil moisture significantly fluctuated during the cotton growing seasons. Timely irrigation significantly boosted soil moisture content by 11.3 %-23.5 %. Soil salinity was lower at the early growth stages of cotton, but it gradually increased over time, peaking at the flowering and boll-setting stages. Appropriate leaching effectively mitigated soil salinity, particularly at the flowering stage, resulting in a reduction of salt accumulation by 13.9 %-32.7 %. As leaching amount increased, the relative content of Ca²⁺ increased, while K⁺ and Na⁺ contents gradually decreased, thereby reducing the relative content of harmful ions and leading to a decrease in SAR by 7.07 %-34.3 %. In terms of biomass, the W3 treatment exhibited the highest level, whih was 1.68 %-25.4 % greater than that of the other treatments. Among the three years, the S3 and S4 treatments consistently produced the highest biomass, with increases of 12.66 %-35.25 % and a slight 0.85 % difference, respectively.</p></div><div><h3>Significance</h3><p>The optimal leaching strategy, combining the W3 irrigation amount with the S3 leaching times achieved the highest seed cotton yield with the lowest yield variability. This underscored the critical importance of suitable irrigation and management practices for enhancing seed cotton yield and mitigating the adverse effects of soil salinity on cotton production. Soil salinity indicators, such as sodium adsorption ratio and exchangeable sodium percentage, played a pivotal role in biomass accumulation and yield stability. A total leaching amount of 300 mm applied at the seedling, budding, flowering, and boll-setting stages was recommended to maximize cotton productivity.</p></div>","PeriodicalId":12143,"journal":{"name":"Field Crops Research","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141915273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genotypic differences in the agronomic performance of ratoon rice in a cool-temperate environment in central Japan","authors":"","doi":"10.1016/j.fcr.2024.109487","DOIUrl":"10.1016/j.fcr.2024.109487","url":null,"abstract":"<div><h3>Context</h3><p>The major challenge for the rice–ratoon-rice system in cool-temperate environments is to ensure high ratooning ability from stubbles after harvesting of main rice crops. The choice of locally adapted cultivars with high ratooning ability is crucial for this system.</p></div><div><h3>Objective</h3><p>We aimed at identifying modern ultrashort-duration cultivars with high ratoon rice yield in central Japan (35°N to 36°N), which represents the northern limit for growing a ratoon crop, and to elucidate the associated growth characteristics.</p></div><div><h3>Methods</h3><p>We evaluated 15 ultrashort-duration cultivars (13 <em>japonica</em> and 2 <em>indica</em>) in 2019, 8 (7 <em>japonica</em> and 1 <em>indica</em>) in 2020, and 3 (all <em>japonica</em>) in 2021 in the rice–ratoon-rice system in Tokyo, Japan.</p></div><div><h3>Results</h3><p>Ratoon rice yield was not negatively correlated with the main rice yield in any year. However, the tiller regeneration rate (the ratio of tiller number in the ratoon rice season to the panicle number in the main rice season) was strongly and significantly positively correlated with ratoon rice yield. The <em>indica</em> cultivars (‘TNAU6484’ and ‘ADT30’) had lower tiller regeneration rates and lower ratoon rice yield than the <em>japonica</em> cultivars. Two <em>japonica</em> cultivars (‘Akitakomachi’ and ‘Ichibanboshi’) had the highest tiller regeneration rate and the highest ratoon rice yield. The stem nonstructural carbohydrate concentration was positively correlated with ratoon bud length at the harvest of the main rice crop.</p></div><div><h3>Conclusions</h3><p>We found significant differences among cultivars in their ratooning ability. The nonstructural carbohydrates accumulated in stems at the harvest of the main rice crop might contribute to quicker and greater growth of ratoon rice crops in central Japan. Despite competition between stems and grains for photosynthate, this growth characteristic does not necessarily lower the yield of the main rice crop in ultrashort-duration <em>japonica</em> cultivars.</p></div><div><h3>Implications</h3><p>Two <em>japonica</em> cultivars were identified for the rice–ratoon-rice system in cool-temperate environments of mid-latitudes. Improvement of ratooning ability of <em>japonica</em> rice should be targeted by thorough evaluation of germplasms to increase ratoon rice yield in cool-temperate environments.</p></div>","PeriodicalId":12143,"journal":{"name":"Field Crops Research","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141915275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of poly-γ-glutamic acid on soil pore structure, maize grain filling, yield and water use efficiency under mulched drip irrigation","authors":"","doi":"10.1016/j.fcr.2024.109528","DOIUrl":"10.1016/j.fcr.2024.109528","url":null,"abstract":"<div><p>Poly-γ-glutamic acid (γ-PGA) is a biodegradable and non-toxic and harmless water retention agent, contributing significantly to in the sustainable development of agriculture. This study focused that investigated effect of γ-PGA on soil pore structure, maize growth, grain filling characteristics, maize yield and water use efficiency under mulched drip irrigation, and the optimal application strategy of γ-PGA. The effect of γ-PGA application rates (0, 40, and 80 kg ha⁻¹) on soil structure was investigated using soil column experiments. Field experiments analyzed the effects of these γ-PGA rates (0, 20, 60 and 80 kg ha⁻¹) on maize growth. The results showed that γ-PGA changed the position and number of soil pores; with the increase of γ-PGA application rate, the number of soil pores increased. The number of soil pores with an equivalent diameter smaller than 300μm increased by 9–14 times, and those with an equivalent diameter larger than 1000μm increased twelvefold. The soil water storage increased by 2∼27 %. γ-PGA prolonged active grain filling period by 1–3 days, increased the maximum grain filling rate (Vmax) by 3∼15 %, the average grain filling rate (Va) by 7∼27 %, and grain weight by 12∼37 %. γ-PGA treatments significantly increased maize plant height, stem diameter, leaf area index (LAI), ear width, grain number per row and 100-grain weight. Compared with P0, yield and water use efficiency for γ-PGA treatment were increased by 4.9∼21.8 % and 1.0∼18.1 %. Based on the Gaussian optimization model and considering local actual conditions, we recommend that the optimal rate of γ-PGA is 70 kg ha⁻¹ in the region. This study provided a theoretical basis for water-saving irrigation of maize under mulched drip irrigation.</p></div>","PeriodicalId":12143,"journal":{"name":"Field Crops Research","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141915272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving rice yield and water productivity in dry climatic zones of West Africa: Season-specific strategies","authors":"","doi":"10.1016/j.fcr.2024.109519","DOIUrl":"10.1016/j.fcr.2024.109519","url":null,"abstract":"<div><h3>Context</h3><p>Irrigated lowland systems contribute most to rice production in sub-Saharan Africa and play a critical role in meeting the increasing rice demand. However, in dry areas of West Africa, negative effects associated with climate change and widespread water scarcity hamper efforts to increase the productivity of irrigated rice. Quantifying rice yields and water productivity and identifying the drivers for the prevailing variability can aid in the targeting and dissemination of appropriate soil, water, and crop management practices.</p></div><div><h3>Objective</h3><p>The main objectives of this research were: (i) to quantify the rice yield gap in representative irrigated systems in dry areas of West Africa, both in wet and dry seasons, and identify factors that can contribute to narrowing the gap, and (ii) to assess the trade-offs or synergies between productivity and resource (water and fertiliser) use efficiency.</p></div><div><h3>Methods</h3><p>We monitored 203 and 192 smallholder farmers’ fields in the wet and dry seasons, respectively, in four contrasting irrigation schemes in Burkina Faso from 2018 to 2020 and assessed key performance indicators (grain yield, water productivity, and nutrient use efficiency). We calculated rice yield gaps (difference between exploitable and actual farmer yields) and identified the drivers of variability of yield and water productivity using machine learning and Shapley Additive exPlanations (SHAP) feature importance.</p></div><div><h3>Results</h3><p>Indicators of productivity and sustainability differed between irrigation schemes and seasons. Rice yield was higher in wet (5.3 Mg ha⁻¹) than in dry seasons (3.7 Mg ha⁻¹), while the variability was higher in the dry (CV = 46%) than in the wet seasons (CV = 29%). Also, the yield gap was slightly higher in the dry (36%) than in the wet seasons (31%). While differences in the number of seedlings per hill and the source of seeds were the key drivers of yield variability in wet-season rice, the split of N fertilizer applications, bird control, and the soil dryness index were the most important in dry-season rice. Furthermore, within seasons, high-yielding fields had higher water productivity, and N, P, and K use efficiencies.</p></div><div><h3>Conclusion</h3><p>These findings suggest that rice yields can be increased without trade-offs with water productivity and nutrient use efficiencies.</p></div><div><h3>Significance</h3><p>This is the first study highlighting the season-specificity of determinants of variability of yield and water productivity in irrigated rice in West Africa. Improved water and fertilizer management can contribute to achieving the dual goal of narrowing the yield gap and improving water productivity, while increasing nutrient use efficiency, particularly in the dry season.</p></div>","PeriodicalId":12143,"journal":{"name":"Field Crops Research","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0378429024002727/pdfft?md5=b8be185c7ecefe832a920980a50c4177&pid=1-s2.0-S0378429024002727-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141947442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Breeding for increased grains/m2 in wheat crops through targeting critical period duration: A review","authors":"","doi":"10.1016/j.fcr.2024.109497","DOIUrl":"10.1016/j.fcr.2024.109497","url":null,"abstract":"<div><h3>Context</h3><p>Continuing to raise the potential yield of wheat through breeding is essential for global food security. Past progress has largely been associated with greater grains/m² (GN), the critical period for the determination of which relates to spike growth, with GN often closely related to spike dry weight at anthesis (g/m²).</p></div><div><h3>Objective/Methods</h3><p>This focussed review outlines the importance of the critical period duration (Ds, in days or °Cdays) and questions how it may be increased genetically, relying partly on the long involvement of the authors in this field, primarily with lower latitude crops of spring-type wheat. Ds is further defined as the interval between flag leaf emergence and first anthesis, each across 50 % of the culms in any crop, a period encompassing most of the accumulation of spike dry matter, in turn determining floret survival and final fertile floret numbers/m².</p></div><div><h3>Results</h3><p>Natural temperature variation and temperature manipulation, particularly in field crops, confirm the dependence of Ds on temperature, which in °Cdays varies from about 300–500, depending on photoperiod. Evidence points to a stronger influence of night than day temperature on Ds, while maintaining the close positive Ds relationship to GN. However, genetic variation in the response of Ds to temperature appears very minor. Ds is inversely related to photoperiod, again with the expected effects on spike dry weight, fertile florets and GN. Extended photoperiod during the critical period showed the greatest reduction in GN per day advance in anthesis. Ds responses can be related to the major photoperiod sensitivity alleles present. A field experiment with a unique reduced photoperiod treatment demonstrated a strong positive effect on Ds, fertile florets and GN, especially in the fully recessive photoperiod-sensitive isoline. While more recent varieties tend to have a longer Ds, experiments targeting selection for Ds or closely related intervals have delivered little change in Ds, which often showed low heritability.</p></div><div><h3>Conclusion</h3><p>Field photoperiod shortening studies needs further testing as proof of concept. Better selection studies are also needed. At the same time, knowledge of the molecular basis of the leaf response to photoperiod is such that gene editing is surely ripe to tackle the challenge of down-regulating this response only during the critical period, thereby increasing Ds and GN. Exogenous application of plant development regulators at the appropriate stage may also provide a way forward.</p></div>","PeriodicalId":12143,"journal":{"name":"Field Crops Research","volume":null,"pages":null},"PeriodicalIF":5.6,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0378429024002508/pdfft?md5=c634a6945f0448f11d0d04019ebdb96a&pid=1-s2.0-S0378429024002508-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141769198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}