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The current context of food security and global geopolitical crises calls for proactive efforts to seek adaptive strategies for limited resources in agriculture. The production of phosphatic-based fertilisers has caused a substantial depletion of natural phosphorus (P) reserves, raising concerns about price increases due to the growing demand for P. The aim of the study is to assess whether the use of liquid organo-mineral P-complexes can be an adaptive strategy to address the issue of the limited P-fertiliser resource. A complete randomised block design was implemented with three replicates, spanning two contrasting cropping seasons under a Mediterranean climate with reduced tillage and rainfed conditions. The study aimed to assess the response of a durum wheat–maize rotation to various rates of liquid organo-mineral P-complexes (humic-complexed phosphate; HCP) in comparison to granular triple superphosphate (TSP). The evaluation focused on several parameters, including P availability, plant architecture, dry matter accumulation, grain yield and yield components and P use efficiency (PUE) for both durum wheat and maize. The results revealed that applying HCP at a rate of 4 or 8 kg ha−1 increased soil P availability on average by 66% and 144%, respectively, compared to the control (no P-fertilisation), although a significant interaction with the monitoring year emerged. For wheat, applying HCP at a rate of 8 kg ha−1 of P resulted in higher grain yield (+15%), protein content (+0.9%) and P uptake (+48%) than the control on average considering both monitoring years. In the season characterised by favourable rainfall patterns, the application of HCP at 5 or 10 kg ha−1 of P for maize showed similar effects in terms of soil P availability, dry matter accumulation, grain yields and PUE. Conversely, in the season marked by a deficiency in summer precipitation, low PUE for maize was observed for HCP fertilisers, although they remained positive, unlike the case of TSP. Using HCP in conservation agriculture appears promising as an adaptive solution to address P-fertiliser scarcity, especially amid food security challenges and global crises. However, further studies are required to validate these findings in diverse pedo-climatic contexts and cropping systems. • Humic complexed P fertiliser (HCP) enhances soil P availability, especially at 0–10 cm depth. • HCP resulted in a general higher maize and wheat grain yield and crops P efficiency. • HCP is promising in the context of conservation agriculture. [ABSTRACT FROM AUTHOR]

Mixing crop species in intercrops often results in yield advantages but the underlying processes are not completely understood. Increased resource capture in intercrops, particularly of light and nutrients, has been frequently demonstrated, but there is less information on the effect of intercropping on the photosynthetic capacity of leaves and on the leaf traits related to photosynthesis. Here we determine whether photosynthetic capacity and associated leaf traits are enhanced in intercropped maize (Zea mays L.), a species frequently used in intercrops. We determined leaf photosynthetic capacity (A 1800) and leaf traits of maize leaves in different canopy layers and at different growth stages in relay strip intercrops with spring wheat (Triticum aestivum L.) or faba bean (Vicia faba L.) and in the maize sole crop. We also measured the distribution of photosynthetically active radiation (PAR) in the canopies. Intercropping with wheat or faba bean resulted in larger specific leaf area (SLA; thinner leaves), lower specific leaf nitrogen (SLN), and lower A 1800 of maize leaves during vegetative growth, and differences were larger for maize intercropped with faba bean than wheat, consistent with stronger shading by faba bean than wheat. After the harvest of companion species, maize leaves received more light in the two intercrops than in the sole maize crop, but this did not result in increases in leaf N concentration, SLN, and A 1800. Results indicate that shading and lower leaf N caused by relay intercropping maize with an earlier sown species negatively affected leaf photosynthetic capacity of maize leaves. The yield increase of maize in relay intercrops was not due to a higher leaf photosynthetic capacity. Options for mitigating or overcoming these negative intercropping effects are discussed. • We measured photosynthesis and leaf traits of maize in relay strip intercropping. • Specific leaf area of intercropped maize was increased due to shading. • Leaf nitrogen concentration was decreased in intercrops with faba bean or wheat. • Leaf photosynthetic capacity of intercropped maize was decreased. • Leaf level responses were not responsible for yield increase in intercrops. [ABSTRACT FROM AUTHOR]

Crop lodging, either stem breaking/stem bending or root lodging, is a major concern for farmers worldwide. In the present study, meta-QTLs, ortho-MQTLs and candidate genes related to lodging and its associated traits were identified using 836 of the 1269 known QTLs retrieved from 107 QTL mapping studies published during 1998–2022. The study resulted in the identification of 86 MQTLs with an average confidence interval (CI) of 1.66 cM (4.26-fold reduction) as against a CI of > 7.08 cM in the initial QTLs. Out of 86 MQTLs, a subset of 12 MQTLs demonstrated stability and robustness, earning them the title of breeders' MQTLs. These selections were made based on criteria such as the number of initial QTLs involved, small CI, high LOD scores, and PVE values. Furthermore, leveraging synteny and collinearity facilitated the identification of 10 ortho-MQTLs shared between wheat and maize. Further, in silico expression analysis allowed the detection of 53 significantly expressed candidate genes encoding different proteins/products including the following: F-box protein, GDSL lipase/esterases, SANT/Myb domain transcription factor, pectin esterase inhibitor domain, glycoside hydrolase family, protein kinase domain, zinc finger domain, cytochrome P450, UDP-glucuronosyl/UDP-glucosyltransferase, glycosyltransferase 61 etc. In addition, 26 lodging tolerance genes from Arabidopsis, rice, and maize were also utilized to identify 34 wheat homologues in wheat MQTL regions. Among these, three genes TraesCS2D02G256600 (TaEREB114 -2D) , TraesCS7B02G340100 (TaIRX14- 7B), and TraesCS1B02G347600 (TaGA2ox4- 1B) were prioritized for qRT-PCR-based expression analysis in one lodging-tolerant (i.e., WH-1105) and one lodging-susceptible (i.e., WH-1184) variety. When comparing these two varieties, we found higher relative expression levels of these three genes in the second basal internode at the milky endosperm stage of the lodging-tolerant variety. The MQTLs, ortho-MQTLs, and candidate genes (CGs) identified in this study can be utilized for marker-assisted selection to improve lodging tolerance and enhance our understanding of the molecular basis of lodging tolerance in wheat. [Display omitted] • Eighty-six MQTLs with significantly reduced confidence intervals were identified. • Twelve MQTLs were recommended for breeding programs for improving lodging resistancein wheat. • Ten ortho-MQTLs were identified between the wheat and maize genomes. • Three genes viz., TraesCS1B02G347600, TraesCS2D02G256600, and TraesCS7B02G340100 were validated using qRT-PCR analysis. [ABSTRACT FROM AUTHOR]

A theoretical basis for optimizing mitigation and adaptation to future climate change can be obtained by determining the carbon balance and their control mechanism in agroecosystems. To better understand summer maize (Zea mays L.)/winter wheat (Triticum aestivum L.) agroecosystems in dry semi-humid carbon balance mechanism, we conducted an in-depth analysis of three-year (2019.6–2022.6) seasonal dynamics of carbon fluxes and their driving factors in summer maize/winter wheat cropland in the Guanzhong Plain combined with path analysis. The results showed that net radiation (R n) was the main direct controlling factor of the net ecosystem exchange (NEE) in the summer maize growing season, followed by leaf area index (LAI). However, LAI was the main factor controlling the seasonal variation of NEE in the winter wheat growing season, followed by R n. Furthermore, LAI was the dominant direct driving factor for the gross primary productivity (GPP) in the summer maize and winter wheat growing seasons. In addition, LAI was the dominant driving factor for the total ecosystem respiration (TER) in the summer maize season, while R n (indirect effect) and LAI (direct effect) were the main controlling factors of TER in the winter wheat season. The NEE values of the summer maize system, winter wheat system, and summer maize/winter wheat system in the study area were from 119 to 221, − 601 to − 595, and − 433 to − 291 g C m − 2 , respectively (the net biological production (NBP) were − 709 to − 437, 220–303, and − 496 and − 260 g C m − 2 , respectively). Notably, the average carbon emission rate of the summer maize/winter wheat agroecosystem in the Guanzhong Plain, considering the carbon output at harvest is 386.2 g C m − 2 year − 1 . Therefore, this study may guide assessment of carbon balance of agroecosystems in dry sub-humid regions, and provide a strong reference for achieving carbon neutrality in local agroecosystems. • Winter wheat dominates net carbon exchange in rotation agroecosystem. • Net radiation and LAI are the dominant controlling factors of carbon balance. • Carbon was exported at an average rate of 386.2 gC m − 2 year − 1 owing to grain removal. [ABSTRACT FROM AUTHOR]

Tillage practice can change soil properties, regulate crop root development and nutrient availability, thus affecting crop growth and yield. However, the effect of no tillage (NT) and deep tillage (DT) on crop yield relative to conventional tillage (CT) under varied environmental and management conditions is unclear in China. We assessed the yield response of wheat and maize to NT and DT relative to CT based on collected field data (518 observations) with a meta-analysis. In general, NT led to negative yield response of both crops relative to CT, whereas maize presented a positive yield response (6.0 %) to NT in sandy soil, and crop yield responses to NT were not significantly different among environmental and management factors. DT significantly increased the yield of wheat (8.7 %) and maize (8.2 %) over CT. For wheat, the yield response to DT was similar across soil textures, climate conditions, experiment durations, N fertilizer rates, and residue managements; however, the interval DT every 2–3 years (13.2 %) and monoculture (13.9 %) increased yield response than the continuous DT (8.4 %) and double cropping system (8.9 %), respectively. The yield response of maize to DT was greater in semidry region (16.1 %) and under high N fertilizer rate (>300 kg N ha−1) (16.1 %), interval DT (12.4 %) compared with those in humid (7.5 %) and semi-humid (6.8 %) regions, low N fertilizer rates (<300 kg N ha−1) (6.9 %−7.5 %), and continuous DT (7.8 %), respectively; but other environmental and management factors did not affect its yield response. Overall, NT presented similar yield of wheat and maize to CT, while DT significantly enhanced their yields; this analysis revealed the crucial environmental and management factors influencing yield response to tillage practices in China, we also gave some suggestions on selecting appropriate tillage methods to realize high crop yield or/and agricultural sustainable development. • NT led to negative yield response of wheat and maize relative to CT. • DT significantly enhanced wheat and maize yields over CT. • Interval DT and monoculture presented better effects on crop yield response to DT. • Environmental and management factors should be considered to enhance yield using DT. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nutrient Expert (NE), is designed through adoption of 4R nutrient stewardship. • Results show that NE achieved higher yields, higher profitability, and lower environmental risks. • An outstanding advantage of NE is user-friendly and can be easily acquired by all farmers with smartphones. Fertilizer has revolutionized crop production, but a lack of evidence-based fertilizer usage has resulted in negative economic and environmental ramifications, particularly for smallholder farmers. This study aimed at developing an innovative nutrient recommendation approach, Nutrient Expert (NE), for improving yields of maize, wheat, and rice while optimizing fertilizer input through adoption of 4R (applying the right source of nutrients at the right rate, time and place) nutrient stewardship technologies, and evaluating the large-scale performance on crop productivity and the environmental impact of cropping systems. Thus, we compared NE to current farmers' practice (FP) and soil test-based fertilizer application (ST) for 1,534 farm field experiments in order to validate the benefits of NE on both crop productivity and environmental protection in the main cereal production areas in China. Overall, the NE treatment achieved 4.4 % higher grain yield and 5.8 % more profit over FP, more yield for rice, but no differences for maize and wheat over ST. Nutrient Expert required 29.0 % and 14.7 % less fertilizer N than FP and ST, respectively. The NE recommendations improved the nitrogen (N) recovery efficiency by 10.8–13.4 percent points over FP across the 1,534 sites. Using the NE approach, on average, reactive N losses and greenhouse gas (GHG) emissions were reduced by 36.2 % and 21.5 % over FP, 16.0 % and 9.9 % over ST, respectively. The NE, as a user-friendly tool, is widely applicable across farm types and climatic regions. It could be beneficial for improving fertilizer use efficiency and maintaining strategic food security for smallholder production areas in China where N fertilizer is inappropriate and usually over applied. This approach could potentially be expanded to help reduce N losses and GHG emissions in other regions globally. [ABSTRACT FROM AUTHOR]

• Organ-specific Ncrit curves and NNI values (leaf, stem, shoot) for wheat, oilseed rape and maize were identified. • Shoot DM based Ncrit curves were comparable to previously published dilution curves. • Plants use primarily the stem than the leaves as temporary N storage at high N availability. The concept of the critical nitrogen (N crit) dilution curve and the derived NNI is generally accepted and used for many crops to describe the crop N status during vegetative growth. Based on field trials with different N treatments carried out in northern Germany, we identified N crit curves based on shoot DM, leaf DM and stem DM for winter wheat (2003/04 - 2007/08), winter oilseed rape (OSR, 2003/04 - 2005/06, 2012/13 - 2014/15), and maize (2007 + 2008), and related the derived organ-specific NNI (Nitrogen Nutrition Index) values. For each sampling date, N crit values were estimated using 'Linear-Plateau' functions, in order to fit a broken function for the shoot and stem fraction consisting of a constant N concentration and a negative power function describing the decrease of the N concentration. For the leaf fractions of wheat and OSR, a linear regression gave the best fit, in maize a negative power function. The relationship between the organ-specific NNI was described by a broken function with two linear branches differing in their slope. Shoot dry matter (DM) based N crit curves were comparable to previously published dilution curves. Maize leaf N concentration was clearly lower than that of wheat and OSR. Leaf N crit of wheat and OSR decreased only slightly during the growth period, but maize N crit showed a more substantial decrease at low DM. Contrarily, all crops showed similar stem N crit curves. Comparison of organ-specific N nutrition index (NNI) revealed that at lower NNI shoot , the increase in NNI leaf was initially higher, while NNI stem exhibited a steeper increase at higher NNI shoot. Our results suggest that plants use primarily the stem compared to the leaves as temporary N storage at high N availability; however, the effect in wheat was less pronounced leading to the question of the capacity of N translocation for an adequate grain protein concentration. [ABSTRACT FROM AUTHOR]

[Display omitted] • WEY increased from 56.92 to 315.42 % in 100 % N under bi cropping system. • Net returns increased from US $ 188.5 to US $ 224.0/ha in 100 % N in bi-cropping system. • Soil OC, available N and P increased significantly in bi-cropping system. • 100 % N application in bi-cropping had highest stability in wheat equivalent yield. • Bi-cropping system recorded higher LER (18.01 to 57.65 %) over sole cropping. We studied the integration of white clover (Trifolium repens) with nitrogen management practices in wheat (Triticum aestivum L.) - maize (Zea mays L.) cropping sequence to find optimum level of N and to enhance forage production. This experiment was laid out in Randomized Block Design with three replications comprising of 12 treatments viz., (T 1) wheat-maize; (T 2) white clover + wheat -maize (0 N); (T 3) white clover (sole); and (T 4 to T 12) 50, 75 and 100 % of recommended N to wheat, maize or both. Application of 100 % N to white clover + wheat - maize (bi-cropping) recorded the highest crude protein in white clover. Wheat equivalent yield (WEY) was computed by multiplying the white clover and maize yields with their respective per unit price to compare the system productivity. The system productivity was found 2.67 (56.92 %) and 5.93 t/ha (315.42 %) higher in 100 % N application to bi-cropping over wheat-maize (0 N) and sole white clover, respectively. Highest net returns (US $ 188.5 and 224.0/ha at farmers' field and research farm, respectively) were also recorded in the same bi-cropping treatment. Bi-cropping along with N application resulted in higher Land equivalent ratio (LER) (18.01–57.65%) over sole cropping. The treatment and treatment x environment (TTE) bi-plot also explained 99.84, 98.70 and 99.63 % of treatment and treatment × environment variation for WEY, Benefit: Cost Ratio (BCR) and LER, respectively. Soil fertility improved significantly in sole white clover and bi-cropping treatments with N application. However, when upto 75 % N of recommended dose of fertilizers (RDF) was applied to bi-cropping system resulted in higher WEY, BCR and LER, which were at par with 100 % N. Thus, cereal-clover bi-cropping system along with 75 % N of RDF can be recommended for sustainable forage and food production; and better soil health in temperate, sub-temperate climatic regions of the world. [ABSTRACT FROM AUTHOR]