Triticum Aestivum Research Articles

Assessing the long‐term effects of conservation agriculture on cotton production in Northeast Louisiana using the denitrification–decomposition model

AbstractConservation agriculture (CA) aims to sustain agricultural production, soil, and environmental health in agroecosystems and has been promoted throughout the United States. The adoption of CA in cotton (Gossypium hirsutum) systems provides both agronomic and environmental benefits. Yet, there is limited information on the long‐term effects of CA practices on crop yield and adaptation strategies. An integrated CA system, that is, cover crops with no‐tillage (NT) instead of conventional agriculture, was implemented in the long‐term field experiments and assessed with an integrated biogeochemical model. Using the denitrification–decomposition model, this study estimated the effects of four different cover crops, for example, native grass (NG), hairy vetch (Vicia villosa), winter wheat (Triticum aestivum L.), and crimson clover (Trifolium incarnatum), on cotton yield under four different nitrogen (N) levels (e.g., 0, 50, 100, and 150 kg N/ha) and estimated responses on carbon (C) sequestration, and ecosystem functionality over a 10‐year study. The NT‐NG 50 N was used as a calibration dataset to accurately estimate the cotton lint yield with a normalized root mean square error (NRMSE) of 21% and model efficiency of 0.3. The calibration data validated the effects of hairy vetch, winter wheat, and crimson clover under the NT‐50 N with NRMSE of 24%, 21%, and 25%, respectively. According to the scenario analysis, the 50 kg N/ha application with a single‐irrigation event (10‐cm depth) was most beneficial for maximizing the cotton yield with cover crop incorporation at the NT system over the long term. The effects of increasing cover crop biomass (i.e., double seed rate) on C content, regardless of N application rates, varied based on the relationship between the main and cover crop species. Besides, the furrow plow tillage system provided efficient C sequestration. The proposed approach stands to provide agricultural and environmental sustainability with the implementation of cover crop or crop residue incorporation instead of increased N application, seed rates, and irrigation events under NT practices.

PROJECTED CHANGE IN DISTRIBUTION PATTERNS OF CROP WILD RELATIVES UNDER CLIMATE CHANGE: A CASE STUDY OF THE FERTILE CRESCENT

The principal aim of this paper is to evaluate alterations in the geographical distributions of priority crop wild relatives (CWRs) within the Fertile Crescent Region. The analysis encompasses a comprehensive set of 441 priority CWRs. To compile species distribution information, a meticulously constructed database of occurrence records was utilized. The process involved gathering current and projected climate data from WorldClim to facilitate the evaluation. This study employed MaxEnt version 3.4.1 for species distribution modeling (SDM) considering two distinct dispersal scenarios. One scenario proposed that the CWR taxa were incapable of adapting to their preferred weather conditions, while the other scenario suggested that CWR could track suitable climates to ensure their survival. The generated maps underwent processing in DIVA-GIS version 7.5. Notably, Aegilops bicornis, a wild relative of bread wheat, and Triticum monococcum, a wild relative of wheat, are anticipated to face substantial impacts due to climate change. Specifically, the dispersal of T. monococcum is predicted to shift toward the north, where new suitable areas are expected to emerge in Northern Iraq. Conversely, Cicer bijugum, a wild relative of chickpea, Vicia grandiflora, a wild relative of common vetch, and Beta corolliflora, a wild relative of sugar beet, are projected to experience a comparatively slight impact from climate change, as their potential distribution areas are estimated to diminish. Overall, this study foresees a decline in CWRs across the Fertile Crescent, particularly noting reduced habitats for the CWRs in Turkey.

Water stress affect water relations, photosynthesis and oxidative defense mechanism in wheat (Triticum aestivum L.)

Water stress is a major obstacle to agricultural production, significantly impacting both yield and quality. During the 2017–18 crop year in Shahriar region near Tehran, Iran, known for its dry and cold climate, a study was conducted to examine the influence of different irrigation levels on the quantitative and qualitative characteristics of various wheat cultivars. The experiment involved three irrigation levels: normal irrigation (control), withholding irrigation at the flowering stage, and withholding irrigation at the seed-filling stage as primary factors, with 21 different cultivars as secondary factors. The analysis showed that irrigation, cultivar type, and their interactions had a significant effect on grain yield, proline, total chlorophyll, carbohydrate content in the first and second internodes during flowering and ripening, as well as on SOD, CAT, GPX, MDA, DT, and D-OH-dG levels at a one percent significance level. Withholding irrigation at the flowering stage had a more severe impact compared to the seed-filling stage. The Rakhshan and Sivand cultivars yielded the highest and lowest grain yields under normal irrigation conditions, while the drought-tolerant Ofogh cultivar showed lower yields when irrigation was withheld at the flowering stage. Water stress led to increased proline levels and higher levels of SOD, CAT, MDA, DT, and D-OH-dG in wheat cultivars. The Rakhshan and Sivand cultivars were identified as drought-tolerant in this region.

An Accurate Representation of the Number of bZIP Transcription Factors in the Triticum aestivum (Wheat) Genome and the Regulation of Functional Genes during Salt Stress.

Climate change is dramatically increasing the overall area of saline soils around the world, which is increasing by approximately two million hectares each year. Soil salinity decreases crop yields and, thereby, makes farming less profitable, potentially causing increased poverty and hunger in many areas. A solution to this problem is increasing the salt tolerance of crop plants. Transcription factors (TFs) within crop plants represent a key to understanding salt tolerance, as these proteins play important roles in the regulation of functional genes linked to salt stress. The basic leucine zipper (bZIP) TF has a well-documented role in the regulation of salt tolerance. To better understand how bZIP TFs are linked to salt tolerance, we performed a genome-wide analysis in wheat using the Chinese spring wheat genome, which has been assembled by the International Wheat Genome Sequencing Consortium. We identified 89 additional bZIP gene sequences, which brings the total of bZIP gene sequences in wheat to 237. The majority of these 237 sequences included a single bZIP protein domain; however, different combinations of five other domains also exist. The bZIP proteins are divided into ten subfamily groups. Using an in silico analysis, we identified five bZIP genes (ABF2, ABF4, ABI5, EMBP1, and VIP1) that were involved in regulating salt stress. By scrutinizing the binding properties to the 2000 bp upstream region, we identified putative functional genes under the regulation of these TFs. Expression analyses of plant tissue that had been treated with or without 100 mM NaCl revealed variable patterns between the TFs and functional genes. For example, an increased expression of ABF4 was correlated with an increased expression of the corresponding functional genes in both root and shoot tissues, whereas VIP1 downregulation in root tissues strongly decreased the expression of two functional genes. Identifying strategies to sustain the expression of the functional genes described in this study could enhance wheat's salt tolerance.

Identification and characterization of the CRK gene family in the wheat genome and analysis of their expression profile in response to high temperature-induced male sterility.

Cysteine-rich receptor-like kinases (CRKs) play many important roles during plant development, including defense responses under both biotic and abiotic stress, reactive oxygen species (ROS) homeostasis, callose deposition and programmed cell death (PCD). However, there are few studies on the involvement of the CRK family in male sterility due to heat stress in wheat (Triticum aestivum L.). In this study, a genome-wide characterization of the CRK family was performed to investigate the structural and functional attributes of the wheat CRKs in anther sterility caused by heat stress. A total of 95 CRK genes were unevenly distributed on 18 chromosomes, with the most genes distributed on chromosome 2B. Paralogous homologous genes with Ka/Ks ratios less than 1 may have undergone strong purifying selection during evolution and are more functionally conserved. The collinearity analysis results of CRK genes showed that wheat and Arabidopsis (A. thaliana), foxtail millet, Brachypodium distachyon (B. distachyon), and rice have three, 12, 15, and 11 pairs of orthologous genes, respectively. In addition, the results of the network interactions of genes and miRNAs showed that five miRNAs were in the hub of the interactions map, namely tae-miR9657b-5p, tae-miR9780, tae-miR9676-5p, tae-miR164, and tae-miR531. Furthermore, qRT-PCR validation of the six TaCRK genes showed that they play key roles in the development of the mononuclear stage anthers, as all six genes were expressed at highly significant levels in heat-stressed male sterile mononuclear stage anthers compared to normal anthers. We hypothesized that the TaCRK gene is significant in the process of high-temperature-induced sterility in wheat based on the combination of anther phenotypes, paraffin sections, and qRT-PCR data. These results improve our understanding of their relationship.

Characterization of whole seeds lipids, extracted lipids composition in bread wheat (T.aestivum L.) genotypes grown in Eskisehir province in Türkiye

Characterization of Whole Seeds Lipids, Extracted Lipids Composition in Bread Wheat (T.aestivum L.) Genotypes Grown in Eskisehir Province in Türkiye Murat OLGUN1, Arzu KÖSE2, Savaş BELEN2, Yaşar KARADUMAN1, Zekiye BUDAK BAŞÇİFTÇİ1, Nazife Gözde AYTER ARPACIOĞLU1, Metin TURAN3 ORCID: 0000-0001-6981-4545; 0000-0003-0675-8958; 0000-0001-7357-8127; 0000-0003-1306-3572; 0000-0002-4034-2537; 0000-0002-5121-4303; 0000-0002-4849-7680 1Osmangazi University, Faculty of Agriculture, Field Crop Department, Eskişehir 2Transitional Agricultural Research Institute, Eskişehir 3Yeditepe University, Faculty of Economics and Administrative Sciences, Department of Agricultural Trade and Management, Istanbul Abstract In this study, chemical components of whole seeds lipids, extracted lipids in wheat genotypes were analysed and effective and important components in lysine, Zn, B6 vitamin and the rate of linoleic acid/linolenic that is important for nutritional quality were determined by decision tree analysis. Bread wheat genotypes, Tosunbey, Alpu 01, ES26, Reis, Nacibey, Altay2000, Bayraktar 2000 and Rumeli, were used. Chemical compositions of whole seeds and seed lipids were investigated. Mean rate of components in lipids to total amount of while seed almost ranges between 53-68%. This mean that rate in minerals, amino acids, fatty acids-enzymes-vitamins was about 53%, 63 and 68%, respectively. Besides, except Ca and the rate of linoleic acid/linolenic acid, differences between whole seeds and lipids in genotypes for the other components were determined as significant at 1%. Differences for Ca and the rate of linoleic acid/linolenic acid were insignificant and significant at 5%, respectively. A substantial amount of components is present in wheat lipid. The ratio of these amounts to the whole seed is approximately one third. Lipid amount and its content composition are important for bread quality. Therefore, consuming whole wheat flour containing embryo and bran provides a better quality nutrition. This rich content of wheat lipid makes it a valuable substance for the cosmetic industry. The results showed that Tosunbey-G1, Alpu 01-G2, ES26-G3 and Nacibey-G5 had the highest nutritional values and better activity. Mn, tryptophan, Na, N and Ca were found as effective components in the shaping and activity of lysine. SOD, Ca, Mg, N, Fe, Na and K were concluded as significant components in Zn activity. Significant components were found in whole seed and lipid as linoleic, glutamine, N, Na and K for B6. In linoleic/linolenic rate, linolenic, N, Na were important components. Key Words: Bread wheat, genotype, minerals, amino acids, whole seeds lipid, extracted lipid, enzymes, vitamins, biplot, decision tree, lysine, Zn, B6 vitamin, rate of linoleic acid/linolenic acid

Cultivated Grassland Types Differently Affected Carbon Flux Downstream of the Yellow River

Cultivated grasslands are an important part of grassland ecosystems and have been proven to be major carbon sinks, then playing an important role in the global carbon balance. The effect of cultivated grassland type (Medicago sativa, Triticum aestivum, Secale cereale, and Vicia villosa grasslands) on carbon flux (including net ecosystem CO2 exchange (NEE), ecosystem respiration (ER), and gross ecosystem productivity (GEP)) downstream of the Yellow River was studied via the static chamber technique and a portable photosynthetic system. Bare land was used as a control. The results showed that the four cultivated grassland types were mainly carbon sinks, and bare land was a carbon source. The cultivated grassland types significantly affected carbon flux. The average NEE and GEP of the grassland types were in the following order from high to low: Medicago sativa, Secale cereale, Triticum aestivum, and Vicia villosa grassland. Stepwise regression analysis showed that among all measured environmental factors, soil pH, soil bulk density (BD), soil organic carbon (SOC), and soil microbial carbon (MBC) were the main factors affecting CO2 flux. The combined influence of soil BD, SOC, and pH accounted for 77.6% of the variations in NEE, while soil BD, SOC, and MBC collectively explained 79.8% of changes in ER and 72.9% of the changes in GEP. This finding indicates that Medicago sativa grassland is a cultivated grassland with a high carbon sink level. The changes in carbon flux were dominated by the effects of soil physicochemical properties.

Effect of Different Thermal Regimes and Moisture Levels on the Growth Parameters of Wheat (Triticum aestivum L.) Crop Grown under Agro-climatic Conditions of Eastern Uttar Pradesh, India

Effect of Different Thermal Regimes and Moisture Levels on the Growth Parameters of Wheat (Triticum aestivum L.) Crop Grown under Agro-climatic Conditions of Eastern Uttar Pradesh, India

Transcriptome analysis provides insights into the sucrose signal transduction in wheat (Triticum aestivum L.)

Transcriptome analysis provides insights into the sucrose signal transduction in wheat (Triticum aestivum L.)

Identification and map-based cloning of an EMS-induced mutation in wheat gene TaSP1 related to spike architecture.

A candidate gene TaSP1 related to spike shape was cloned, and the gene-specific marker was developed to efficiently track the superior haplotype in common wheat. Spike shape, an important factor that affects wheat grain yield, is mainly defined by spike length (SPL), spikelet number (SPN), and compactness. Zhoumai32 mutant 1160 (ZM1160), a mutant obtained from ethyl methane sulfonate (EMS) treatment of hexaploid wheat variety Zhoumai32, was used to identify and clone the candidate gene that conditioned the spike shape. Genetic analysis of an F2 population derived from a cross of ZM1160 and Bainong207 suggested that the compact spike shape in ZM1160 was controlled by a single recessive gene, and therefore, the mutated gene was designated as Tasp1. With polymorphic markers identified through bulked segregant analysis (BSA), the gene was mapped to a 2.65-cM interval flanked by markers YZU0852 and MIS46239 on chromosome 7D, corresponding to a 0.42-Mb physical interval of Chinese spring (CS) reference sequences (RefSeq v1.0). To fine map TaSP1, 15 and seven recombinants were, respectively, screened from 1599 and 1903 F3 plants derived from the heterozygous F2 plants. Finally, TaSP1 was delimited to a 21.9Kb (4,870,562 to 4,892,493bp) Xmis48123-Xmis48104 interval. Only one high-confidence gene TraesCS7D02G010200 was annotated in this region, which encodes an unknown protein with a putative vWA domain. Quantitative reverse transcription PCR (qRT-PCR) analysis showed that TraesCS7D02G010200 was mainly expressed in the spike. Haplotype analysis of 655 wheat cultivars using the candidate gene-specific marker Xg010200p2 identified a superior haplotype TaSP1b with longer spike and more spikelet number. TaSP1 is beneficial to the improvement in wheat spike shape.

Performance of low-input agriculture with ZBNF-A case study on groundnut (Arachis hypogaea L.)–wheat (Triticum aestivum L.) cropping system in Saurashtra region of Gujarat

Sustainable low-cost farming in (groundnut based) cropping system offers a much-needed alternative to conventional input-intensive agriculture. Keeping this in view a field experiment was conducted during rainy (kharif) season of 2022–23 at ICAR-Directorate of Groundnut Research, Junagadh, Gujarat on groundnut (Arachis hypogaea L.) to evaluate the performance of low-input agriculture with ZBNF (Zero-budget natural farming) vis-avis others. Experiment was conducted in a split plot design having 3 different farming practices, viz. Natural farming (NF); Integrated crop management (ICM or conventional farming); and Organic farming (OF) practices in main plot using 2 cultivars ‘GJG-22’ (Virginia Bunch) and ‘TG 37A’ (Spanish Bunch) in large sub plot (~1/100th of a hectare), replicated 8-times. Further, these permanent plots of 3 farming practices were cultivated with wheat (Triticum aestivum L.) (two cultivars, viz. ‘GW 451’ and ‘Lok 1’) in rotation during winter (rabi) season of 2022–23 following a residual exhaustive fodder crop of pearl millet [Pennisetum glaucum (L.) R.Br.] grown during spring/summer 2021– 22 prior to the experimentation. The study revealed that pod yield to the tune of 1,316–1,630 kg/ha was realized with low cost NF (or ZBNF) practice (higher yields with Spanish Bunch) vis-a-vis 1,448–1,779 kg/ha in OF practice. On the contrary, higher pod yield of 1,679–1,965 kg/ha was realized with the ICM practice employing improved production technologies. The growth/developmental parameters/values including economics and total system productivity were also higher under ICM practice. Furthermore, higher values in respect of all the groundnut plant attributes including economics and nutrient (NPK) uptake, and its efficiency (NPK uptake/100-kg pod) were evident under ICM practice. Similar crop responses were conspicuous in case of the succeeding wheat crop. Thus, overall crop response to farming practices were in the order: ICM>OF>NF; and the ratio of N, P, and K uptake for realization of higher per unit productivity (across farming practices and varieties) was observed to be 6.8:1.0:2.2 for groundnut and 3.9:1.0:3.3 for wheat. Thus, ICM practice comprising of judicious use of chemical fertilizers, manure and pesticides use was advantageous for realizing higher yield and return in groundnut-wheat. Further efforts are made to realize higher productivity of ecofriendly farming practices (ZBNF and OF).

Preceding kharif crops and fertilizer influence on growth, yield and nutrient requirement of succeeding wheat (Triticum aestivum)

A field experiment was conducted during 2 consecutive rainy (kharif) and winter (rabi) season each of 2020–21 and 2021–22 at C.P. College of Agriculture, Sardarkrushinagar Dantiwada Agricultural University, Sardarkrushinagar, Gujarat to study the effect of preceding kharif crops and fertilizer on growth, yield, economics and nutrient requirement of succeeding wheat (Triticum aestivum L.) crop. The experiment was laid out in split plot design comprising of 4 kharif crops, viz. greengram [Vigna radiata (L.) R. Wilczek], sesame (Sesamum indicum L.), pearl millet [Pennisetum glaucum (L.) R.Br.] and fodder sorghum [Sorghum bicolor (L.) Moench] as main plots and 5 fertilizer treatments, viz. 100% RDF (120 kg N + 60 kg P2 O5 + 40 kg K2 O/ha); 75% RDF; 50% RDF; 75% RDF + Azotobacter + PSB (phosphate solubilizing bacteria); and 50% RDF + Azotobacter + PSB as sub plots with four replications. Wheat grown after kharif greengram had better growth parameters and yield attributes which was reflected in an increase in grain (4.78 t/ha) and straw (6.41 t/ha) yield of wheat. Among different fertilizer treatments, wheat fertilized with 100% RDF recorded significantly higher grain (4.60 t/ha) and straw yield (6.20 t/ha). Nutrient uptakes by grain and straw increased under wheat grown after greengram and fertilized with 100% RDF. Greengramwheat crop sequence and wheat fertilized with either 100% RDF or 75% RDF along with Azotobacter + PSB seed inoculation earned higher net realization and B:C ratio.

Effect of zinc and boron on grain quality of wheat (Triticum aestivum) in north-western plain zone of India

An experiment was conducted to study the “Effect of zinc and boron on grain quality of wheat (Triticum aestivum L.) during the winter (rabi) season of 2018–2019 and 2019–20 at the agronomy research farm of IFTM University, Lodhipur Rajput, Moradabad, Uttar Pradesh. Ten treatments, viz. T1 , Control (no fertilizer); T2 , zinc @ 5 kg/ha (SA); T3 , zinc @ 1 kg/ha (FA); T4 - zinc @ 1 + 1 kg/ha (2 FA); T5 , zinc @ 5 kg/ha (SA) + zinc @ 1 kg/ha (FA); T6 , boron @ 0.5 kg/ha (SA); T7 , boron @ 0.1 kg/ha (FA); T8 , boron @ 0.2 kg/ha (2 FA); T9 , boron @ 0.5 kg/ha (SA) and boron @ 0.1 kg/ha (FA) and T10-, zinc @ 5 kg/ha + boron @ 0.5 kg/ha (SA) were comprised in randomized block design (RBD) with the three replications. The results revealed that different levels and application methods of zinc and boron significantly improved the grain quality of wheat. Maximum Zn content (35.4 and 35.9 mg/ha) and Zn uptake (185.1 and 197.1 g/ha) in 2018–19 and 2019–20, respectively were recorded with Zn @ 5 kg/ha (SA) + zinc @ 1 kg/ha (FA). Moreover, maximum B content (58.5 and 59.5 mg/ha) and B uptake (361.9 and 376.4 g/ha) in 2018–19 2019–20, respectively were observed with B @ 0.5 kg/ha (SA) and B @ 0.1 kg/ha (FA). Maximum protein content in grain (12.6 and 12.7%) and protein yield (712.8 and 744.9 kg/ha) was recorded under Zn - 5 kg/ha (SA) + B 0.5 kg/ha (SA) in 2018–19 and 2019–20, respectively

Halophilic microbial formulations for improving crop productivity and soil health under saline Vertisols of Gujarat

A study was carried out during winter (rabi) seasons of 2018 and 2019 at research farm of ICAR-Central Soil Salinity Research Institute, Regional Research Station, Bharuch, Gujarat to find out the effect of various halophilic microbial formulations in combination of organic manure and chemical fertilizers on winter (rabi) wheat (Triticum aestivum L.) productivity under saline Vertisols. Experiment was conducted in a randomized block design (RBD) comprised of 5 treatments, viz. T1 , Un-inoculated + Vermicompost @2.5 t/ha + 100% RDF (recommended dose of fertilizers); T2 , Un-inoculated + Vermicompost @2.5 t/ha + 75% RDF; T3 , Vermicompost @2.5 t/ha + 75% RDF + Halo-Azo inoculation; T4 , Vermicompost @2.5 t/ha + 75% RDF + Halo-PSB inoculation; and T5 , Vermicompost @2.5 t/ha + 75% RDF + Mix of Halo-Azo and Halo-PSB inoculation, replicated thrice. Results showed that application of different halophilic microbial formulations like Halo-Azo (Azotobacter sp. and Bacillus sp.) and Halo-PSB (consortia of Eneterobacter and Brevibacterium sp.) with vermicompost @2.5 t/ha + 75% RDF (recommended dose of fertilizers), provided at par yield with full dose (120 : 60 : 00; N : P : K kg/ha) of fertilizers, thus able to reduce 25% chemical fertilizer dose. Halo-Azo formulation performed better for improving crop yield as compared to Halo-PSB formulation. Combined application of Halo-Azo and Halo-PSB with vermicompost @2.5 t/ha and 75% RDF performed the best and provided significantly higher grain yield (2.75 t/ha) as compared to other treatments. Single and combined application of Halo-Azo and Halo-PSB with vermicompost @2.5 t/ha and 75% RDF also improved soil health parameters and significant results, i.e. declined EC (2.46 dS/m) and pH (7.33), improved organic carbon (0.69%) and nutrient availability (available N: 299.8 kg/ha and P: 28.7 kg/ha) were obtained. Results showed that integration of halophilic microbial formulations with organics and chemical fertilizers was able to improve wheat yield up to 15% than conventional farming under saline Vertisols of Gujarat.

Climate change shocks and crop production: The foodgrain bowl of India as an example

Global warming is causing climate change (CC) characterized by increased frequency of heatwaves, droughts, erratic rains, hailstorms, cloudbursts, floods, landslides etc. The CC has already adversely affected ecosystems. In spite of efforts to mitigate greenhouse gas (GHG) emissions, which lead to warming, the global temperature during 2011–20 was 1.1°C above that during pre-industrial era. The projections are that warming will continue to increase and adverse effects will intensify particularly in developing countries like India. In India a number of studies have recorded wide spatial variability in rainfall, though, many reported a general overall negative trend since mid-20th century. Further, varying pattern of rainfall has been recorded in three agroclimatic regions of Punjab state, the granary of India. Unseasonal rains followed by spiked temperature during winter (rabi) season of 2021–22 reduced wheat (Triticum aestivum L.) yield in Punjab by 651 kg/ha and by 301 kg/ha in Haryana compared to 2020–21. Further, the grain was of lower quality. During rainy (kharif) season of 2022, Southern Rice Black-streaked Dwarf Virus (SRBSDV), appeared for the first time in Punjab and Haryana. Some farmers ploughed the affected fields. Adverse weather during rabi 2022–23 also, reduced the wheat yield (143–150 kg/ha) in these states. At the national level, erratic weather during rabi 2021–22 and kharif 2022 caused losses of about 3 mt of grain of each of wheat and rice (Oryza sativa L.). The projected increased adverse effects due to intensified CC include food insecurity. Thus, there is an emergent need to accelerate implementation of adaptation and mitigation strategies in agriculture. The adaptation options include cultivar improvement, conservation agriculture altering growing seasons, crop diversification and sustainable soil, and water resource management. In the process of adaptive management of crop production, adjusting sowing dates and breeding cultivars having varying duration in consonance with CC has been one of the central aspects. Shifting sowing dates to find appropriate crop cultivation season is a low-cost measure. However, cultivar development is time and resource consuming. Novel biotechnological tools enable fast cultivar development with precision, and facilitate mobilization of genes from wild-weedy relatives, which are rich in genes conferring resistance/tolerance to biotic and biotic stresses, required to combat CC challenge. In view of CC stress on water resources, improving water-use efficiency (WUE) has gained importance. Sensor-based micro-irrigation/fertigation has great potential to enhance water and fertilizer-use efficiency. Similarly, the application of other smart technologies like nanotechnology, sensor-based pesticide application, bio-fertilizers and bio-pesticides, need to be mobilised. In view of agro-ecological diversity in India, right-sized regionspecific technology packages have to be developed implying that crop research will expand exponentially. This needs strengthening of human resources and institutional infrastructure, expanding and linking basic and applied researches, and fortifying inter-disciplinary/inter-institutional collaborations to develop and diffuse technology innovations. Enabling factors include enhanced funding and international cooperation. All-out efforts are needed to have more climate-resilient agriculture.

Chickpea (Cicer arietinum)-based intercropping systems in Rajasthan’s Hadoti region: Productivity and economic viability

A study was carried out during three successive winter (rabi) seasons (2018–19 to 2020–21) at the Agricultural Research Station in Ummedganj, Kota, Rajasthan to determine the productivity and economic viability of intercropping systems based on chickpea (Cicer arietinum L.) in the Hadoti region of Rajasthan. Nine various chickpeabased intercropping systems, viz. Sole chickpea; Sole linseed (Linum usitatissimum L.); Sole coriander (Coriandrum sativum L.); Sole wheat (Triticum aestivum L.); Sole mustard [Brassica juncea (L.) Czern.]; Chickpea + linseed (6:2); Chickpea + coriander (6:2); Chickpea + wheat (6:2); and Chickpea + mustard (6:2) were investigated in a randomized block design (RBD) with three replications. According to combined statistics, the chickpea + mustard intercropping system had the highest chickpea grain yield and equivalent yield (1,865 kg/ha and 2,574 kg/ ha, respectively) when compared to all other intercropping systems. Results of competitive indices revealed that compared to rest of the intercropping system, chickpea + mustard (6:2) recorded significantly higher LER (1.25), MAI (18,462) and SPI (2912 kg/ha), while the lowest land equivalent ratio (LER), monetary advantage index (MAI), system productivity index (SPI) and production efficiency (PE) were recorded in the chickpea + wheat intercropping system. The chickpea + mustard intercropping system yielded values of competition ratio (3.56), aggressivity (-0.05), system profitability index (2912), relative crowding coefficient (13.2), and area time equivalent ratio (1.24), that were sustainable and producible in comparison to other treatments. In terms of economics, compared to all other intercropping and solo crops, the chickpea + mustard intercropping system yielded the chickpea’s most significant net returns (`93,681/ha) and benefit cost (B:C) ratio (3.11). So, for south-eastern Rajasthan, the mustard and chickpea intercropping system is a productive and sustainable system.

Microbial population and yield of rice–wheat system under variable irrigation and nutrient management

A field experiment was conducted during rainy (kharif) season of 2018–19 and winter (rabi) season of 2019–20 at the Water Management Research Farm of CSK Himachal Pradesh Agricultural University, Palampur, Kangra, Himachal Pradesh to study the effect of moisture and nutrient management practices on different soil microbial entities and crop yields in rice (Oryza sativa L.)–wheat (Triticum aestivum L.) system. Experiment was laid out in a split-plot design with 3 replications. Treatments comprised of 3 irrigation levels, viz. Recommended critical stages regimes; Irrigation at 0.8 CPE (cumulative pan evaporation) (rice) and 0.6 CPE (wheat); Irrigation at 1.0 CPE (rice) and 1.0 CPE (wheat) assigned to main-plots and 4 nutrient management practices, viz. Inorganic; Organic; Natural farming; and Integrated management allotted to sub-plots. Irrigation at critical stages resulted in significantly higher rice yield, bacterial, azotobacter, phosphate solubilizing bacteria (PSB), actinomycetes population. However, fungi population increased under higher moisture regimes. In case of wheat crop, irrigation at 1.0 CPE resulted in a significantly higher yield (7.5% higher over irrigation at critical stages) in both the years of study. Organic and integrated nutrient management practices being statistically at par with each other recorded significantly higher microbial population. A significantly higher fungi population was, however, recorded with natural farming. The highest crop yields were obtained with integrated nutrient management (3.4 t/ha rice and 3.6 t/ha wheat in second year). The best combination for rice was irrigation at critical stages along with integrated nutrient management. Whereas, for wheat irrigation at 1.0 CPE with same nutrient management proved to be the best. Hence it is recommended to follow integrated nutrient management and irrigation at critical stages in rice and at 1.0 CPE in wheat for higher productivity as well as for improved biological properties of soil.

Multi-species weed detection and variable spraying system for farmland based on W-YOLOv5

Weed infestations have the potential to cause significant economic losses for farmers as a result of diminished crop yields and escalated labor and input costs linked with weed management. Traditional weed control methods often entail indiscriminate application of herbicides across entire fields, irrespective of weed density or species composition. In this investigation, we propose a hierarchical detection algorithm for identifying multi-species weeds and have devised a variable spraying system in agricultural settings. The weed classification detection algorithm comprises two components: crop seedling target detection and weed detection. The enhanced YOLOv5 algorithm was initially merged with Vision Transformer (ViT) to introduce the W-YOLOv5 crop seedling target detection algorithm. Experimental validation results indicate that the mean average precision (mAP) of the proposed W-YOLOv5 stands at 87.6%, representing a 3.2% increase over the original YOLOv5. Compared with YOLOv7, this method demonstrates a 4.4% improvement in mAP, accompanied by an 80.14% reduction in floating point operations (FLOPs). These findings underscore the effectiveness of the proposed crop seedling target detection algorithm in ensuring detection accuracy while minimizing model FLOPs. Subsequently, following the detection of crop seedlings, the Hue, Saturation, and Value (HSV) color space filtering algorithm was employed to identify the locations of all weeds in the image, thereby facilitating the detection of weeds among wheat (Triticum aestivum L.), radish (Raphanus sativus L.), cucumber (Cucumis sativus L.), soybean (Glycine max (L.) Merr.), and corn (Zea mays L.) seedlings. Finally, the severity of weed infestation in farmland was classified into five levels. Leveraging these severity levels, we developed a variable spraying system and integrated the developed algorithm into the system. Field validation experiments demonstrate that at a speed of 4 km/h, the spraying accuracy of the system can reach 90.32%, effectively enabling precise variable spraying.

Responses of soil aggregation and aggregate‐associated nitrogen to straw return in China: Evidence from a meta‐analysis and a pot experiment

AbstractEnhancing soil structure and soil nitrogen availability is the key to sustainable agricultural development in global cropping systems. Straw return can affect soil aggregation, but the results of recent studies on the influence of straw return on soil aggregation are not consistent, and the distribution and availability of straw‐derived nitrogen in soils are still unclear. Here, a meta‐analysis of the effects of straw return on soil aggregation was conducted based on 57 studies published in China over the past 10 years. Moreover, combined with a pot experiment, the distribution and transfer characteristics of the two main wheat (Triticum aestivum L.)‐preceding crops, corn (Zea mays L.) and soybean (Glycine max L.) straw‐derived nitrogen in the soils were studied by using the 15N‐tracer method in the main wheat‐producing areas of China. 15N‐labeled straw was introduced into soils in pots at rates of 0.3% and 0.5% of the soil dry mass and incubated 60%–70% of the field water capacity throughout the entire growth period of wheat (220 days). A meta‐analysis revealed that straw return significantly improved the mass ratio of large macro‐aggregates (LM%) and small macro‐aggregates (SM%) but significantly decreased the mass ratio of micro‐aggregates (MI%) and silt plus clay‐size particles (CS%), with mean effect sizes of 36.27%, 9.06%, −8.26%, and −21.32%, respectively. The mean weight diameter (MWD) and geometric mean diameter (GMD) also increased by 21.48% and 15.64%, respectively. Compared with SM%, LM% made a greater contribution to the stability of soil aggregates. Moreover, only LM% showed a significant positive correlation with the corresponding aggregate‐associated nitrogen content, which was an important reason for the improvement in soil nitrogen availability after straw return. The positive effect of straw return on soil aggregation was greatest when the soil pH was close to 6.5–7.5, the average annual temperature was greater than 15°C, and the average annual rainfall was close to 800–1000 mm. The results of the pot experiment revealed that the proportions of straw‐derived nitrogen in >2 mm aggregates were 1.21–1.28, 1.50–2.23, and 1.34–1.74 times greater than those in 0.25–2, 0.053–0.25, and <0.053 mm aggregates, respectively. Moreover, the proportion of straw‐derived nitrogen content of aggregates of different particle sizes showed that the proportion of straw used to reach 0.5% of the soil dry weight was greater than 0.3%, which was 1.09–1.66 times greater, and that of soybean straw was significantly greater than that of corn straw, which was 1.50–2.28 times greater. At application rates of 60 g pot−1 and 100 g pot−1 straw, the absorption of soybean straw‐derived nitrogen by wheat was 1.83 and 2.15 times greater than that of corn straw‐derived nitrogen, respectively. In conclusion, straw return effectively improved soil aggregate stability and nitrogen availability, which was closely related to the increase in soil LM%. Soybean straw can stabilize soil aggregates better than corn straw, and its straw‐derived nitrogen is an important nitrogen source for subsequent wheat crops.

195 Incidence of porcine ear necrosis in nursery pigs under commercial conditions is reduced with stimbiotic

Abstract Three studies were conducted to evaluate the potential benefit of a stimbiotic on porcine ear necrosis and the fecal microbiome in nursery pigs. In experiment 1, 600 mixed-sex piglets were randomly placed in 20 pens with 30 pigs/pen (n = 10). The pigs were fed a common wheat and barley-based nursery diet (CON) or CON with stimbiotic (Signis, 0.15g/kg; STB). Incidence of ear necrosis was recorded on individual animals at 28 d post-weaning. Mortality was analyzed using ANOVA and PEN was evaluated using a chi-square test. In experiment 2, a total of 65,200 pigs were placed on trial in 8 nursery barns. Treatments were assigned to a quadrant within each barn (n = 8). Newly weaned pigs were fed a common corn-soy nursery diet (CON) or CON with stimbiotic (Signis, 0.1g/kg; STB). Ear necrosis was classified as either: 1) nominal lesions or 2) moderate to severe lesions and was recorded at 1, 3, and 5 wk post weaning. Mortality and injectable treatments were recorded. Mortality data were analyzed using a binomial regression. A Poisson regression was used to analyze the incidence of PEN and injectable treatment rate with the fixed effect of treatment and random effects of sow farm, site, and barn. In experiment 3, a total of 47,200 pigs in 10 nursery barns were randomly assigned to either a standard nursery diet (CON) or CON with stimbiotic (Signis, 0.1 g•kg-1•ton-1; STB). Mortality was recorded throughout the 6-wk trial and PEN score was recorded at d 42. Fecal samples were collected on 7, 21, and 42 d post-weaning for 16S rRNA sequencing and predictive metabolic function analysis. In experiment 1, no differences in mortality were observed (P > 0.10). A total of 156 pigs in the CON fed group developed PEN, whereas only 27 pigs in the STB group developed PEN (52% vs. 9%; P < 0.01). In experiment 2, there was no difference among treatments for mortality. Pigs fed the STB treatment required 15% fewer injectable treatments than pigs fed the control (P < 0.05). No differences of PEN were observed in wk 1 and 3; however, at 5 wk post-weaning, incidence of PEN was 23% less in pigs fed the STB the the control fed pigs (P < 0.05). In experiment 3, the pigs fed STB had decreased incidence of ear necrosis (3.09% vs 4.08%; P < 0.05) and mortality (2.42% vs 2.86%; P < 0.05), overall reducing PEN and mortality by 32% and 18%, respectively. The fecal microbiome of pigs fed CON was associated with the chondroitin sulfate degradation pathway, an important component of cartilage. In conclusion, feeding a stimbiotic appears to be beneficial in nursery pigs to help alleviate challenges with PEN, which is potentially driven by a beneficial shift in the pig’s microbiome.