Improving Nutrient Use Research Articles

A genome-wide association study unveils key chromosome regions involved in determining sodium accumulation in wheat under conditions of low potassium supply

Improving nutrient use efficiency is an important objective in modern breeding programs. In this work, we examined potassium utilization efficiency (KUtE) and traits potentially related to it in a formerly genotyped, geographically diverse population of bread wheat (Triticum aestivum) under low potassium supply conditions. Our results unveil the existence of a large variation within the population for the traits examined. A genome-wide association study, based on a single-locus model, identified 15 markers associated with some of those traits. No marker-trait association was found using that tool for KUtE, but the use of a multi-locus approach suggested that additional marker-trait associations may be present, including whole-plant KUtE. Besides, the existence of a significant correlation between KUtE and sodium accumulation in shoots suggests the possibility of pyramiding traits associated with sodium homeostasis to improve this efficiency. In this regard, two discrete regions mapped on the long arm of chromosome 1B (1BLA and 1BLB) were associated with variation in sodium accumulation as detected with the single and multi-locus models used. Further exploration of the potential function of the genes placed in these regions, and their expression patterns, suggested likely candidates for this trait. Among the candidates placed in 1BLA region, we found TraesCS1B02G370500, TraesCS1B02G370600, and TraesCS1B02G370900, coding for putative Calcineurin B like proteins. Region 1BLB contain TraesCS1B02G388900 coding for a kinase and other genes including TraesCS1B02G389700, TraesCS1B02G389800 and TraesCS1B02G389900 coding for Ethylene-responsive transcription factors. The information here provided can be useful in breeding programs aimed to manipulate sodium accumulation through marker-assisted selection.

Main factors affecting nutrient and water use efficiencies in spring canola in North America: a review of literature and analysis

Improving nutrient and water use efficiencies by optimizing field management practices are important strategies to increase economic and environmental sustainability of canola production in North America. The objective of this study was to review recent research publications and quantitatively assess the impact of field management practices on the efficiency of water and selected macronutrients [nitrogen (N) and sulfur (S)] in canola and to identify the most effective cultural practices for improved efficiencies. The results showed that, overall, the addition of N and S inputs in studies across North America increased yield but had a negative impact on nitrogen use efficiency (NUE) and sulfur use efficiency (SUE) compared with corresponding controls. Split-applied N in spring can improve NUE, but these improvements are mostly dependent on the soil moisture content. SUE is improved when N is supplied to complement the S application. Sulfate forms of S are more readily available and should be applied early in the season, whereas elemental S must be applied in the fall to improve SUE. Maintenance of adequate soil moisture conditions during the reproductive phase of the canola crop improves water use efficiency (WUE). Supplementary irrigation improves SUE, but most canola crops are grown under rain-fed conditions in North America. Maintaining tall stubble until spring and then incorporating it with N improved WUE in canola. In summary, our analyses suggest that further research is required on the integration of canola genotypes with improved nutrient and water use efficiencies and effective management.

The Nutrient Expert decision support system improves nutrient use efficiency and environmental performance of radish in North China

Excessive fertilization has led to nutrient use inefficiency and serious environmental consequences for radish cultivation in North China. The Nutrient Expert (NE) system is a science-based, site-specific fertilization decision support system, but the updated NE system for radish has rarely been evaluated. This study aims to validate the feasibility of NE for radish fertilization management from agronomic, economic, and environmental perspectives. A total of 46 field experiments were conducted over four seasons from April 2018 to November 2019 across the major radish growing regions in North China. The results indicated that NE significantly reduced N, P2O5, and K2O application rates by 98, 110, and 47 kg ha−1 relative to those in the farmers’ practice (FP), respectively, and reduced N and P2O5 inputs by 48 and 44 kg ha−1, respectively, while maintaining the same K2O rate as soil testing (ST). Relative to FP and ST, NE significantly increased radish yield by 2.7 and 2.6 t ha−1 (4.2 and 4.0%) and net returns by 837 and 432 USD ha−1, respectively. On average, NE significantly improved the agronomic efficiency (AE) of N, P, and K (relative to FP and ST) by 42.4 and 31.0, 67.4 kg kg−1 and 50.9, and 20.3 and 12.3 kg kg−1; enhanced the recovery efficiency (RE) of N, P, and K by 11.4 and 7.0, 14.1 and 7.5, and 11.3 and 6.3 percentage points; and increased the partial factor productivity (PFP) of N, P, and K by 162.9 and 96.8, 488.0 and 327.3, and 86.9 and 22.4 kg kg−1, respectively. Furthermore, NE substantially reduced N and P2O5 surpluses by 105.1 and 115.1 kg ha−1, respectively, and decreased apparent N loss by 110.8 kg ha−1 compared to FP. These results indicated that the NE system is an effective and feasible approach for improving NUE and promoting cleaner radish production in North China.

Application of a Biostimulant (Pepton) Based in Enzymatic Hydrolyzed Animal Protein Combined With Low Nitrogen Priming Boosts Fruit Production Without Negatively Affecting Quality in Greenhouse-Grown Tomatoes.

Improved nutrient use efficiency together with the use of biostimulants have been little explored thus far to improve fruit yield and quality in economically relevant crops. The aim of this study was to determine the additive or synergistic effects, if any, of the application of an enzyme hydrolyzed animal protein biostimulant (Pepton) combined with priming with low nitrogen (N) in the production and quality of greenhouse tomatoes. Biostimulant treatment (Pepton at a dose equivalent of 4 kg/ha) was applied by ferti-irrigation for 2 months during the vegetative phase both in controls (watered with nutrient solution) and nutrient efficient crop (NEC), in which plants were primed with low N by exposing them to a 30% N deficiency for 2 months, and then recovered for 1 month before fruit production. Foliar water and N contents, pigments, maximum PSII efficiency (Fv/Fm ratio), and phytohormones [including abscisic acid (ABA), salicylic acid (SA), jasmonic acid (JA), and cytokinins] were measured prior and at 4 and 8 weeks after the first application. Fruit production and quality [as indicated by total soluble sugars (TSS) and acidity (TA), and the contents of lycopene, vitamin E, and vitamin C] were measured 1 month later at harvest. Priming with low N availability (NEC plants) doubled (p < 0.001) fruit production (due to an increase in the number of fruits), tended to increase (p = 0.057) by 20% the amount of TSS and increased (p < 0.05) the contents of lycopene (by 90%) and vitamin E (by 40%). Pepton displayed a tendency, almost significant, to improve (p = 0.054) total fruit production both in control and NEC plants, thus showing an additive effect to low N priming in boosting fruit production. Pepton maintained fruit quality in terms of sugar accumulation, total acidity and the contents of carotenoids, vitamins C and E. Pepton-related improvement in fruit production seemed to be related, at least partially, to an increased accumulation of cytokinins and photosynthetic pigments in leaves, which might favor vegetative vigor and ultimately fruit yield. In conclusion, Pepton application was effective in improving the yield of greenhouse tomatoes showing additive effect with low N priming, without negatively affecting fruit quality.

Benefits of biochar, poultry manure and biochar–poultry manure for improvement of soil properties and sweet potato productivity in degraded tropical agricultural soils

Studies on the effects of biochar and poultry manure on soil properties and sweet potato productivity are scarce. Hence, field experiments were conducted during 2019 and 2020 cropping seasons at two sites to evaluate the effects of biochar (B), poultry manure (PM) and their combined application on soil physical and chemical properties, growth and tuber yield of sweet potato (Ipomoea batatas L.). Each year, the experiment consisted of 4 × 3 factorial combinations of biochar (0, 10.0, 20.0 and 30.0 t ha −1) and poultry manure (0, 5.0 and 10.0 t ha −1). The experiment was laid out in a randomized complete block design with three replications. The results showed that combined application of B and PM improved soil physical and chemical properties, growth and tuber yield of sweet potato better than sole application of B and PM. In both years, there were significant interactions of B and PM (B × PM) on soil properties and sweet potato variables that were measured, indicating the potential of B in improving nutrient use efficiency of PM amendment. It was found that the highest application rate of 30.0 t ha −1 B and 10.0 t ha −1 PM (B30+PM10) gave the highest tuber yield of sweet potato at both sites. Averaged over two years, the highest application rate of B at 30.0 t ha −1 and PM at 10.0 t ha −1 (B30+PM10) significantly increased tuber yield of sweet potato by 108, 147, 196, 89, 124 and 220%, compared with sole B at 30.0 t ha −1 (B30+PM0), sole B at 20.0 t ha −1(B20+PM0), sole B at 10.0 t ha −1 (B10+PM0), sole PM at 10.0 t ha −1(B0+PM10), sole PM at 5.0 t ha −1(B0+PM5) and no application of B or PM (control) (B0+PM0), respectively. Lowest tuber yield was obtained for the control. The multiple regressions revealed that bulk density, porosity and moisture content and soil chemical properties (pH, OC, N, P, K, Ca and Mg) significantly influenced the tuber yield of sweet potato and therefore dictated the performance of sweet potato in Alfisols of southwest Nigeria. The highest application rate of 30.0 t ha −1 B and 10.0 t ha −1 PM were found best on most of the measured soil physical and chemical properties, growth and tuber yield of sweet potato. The results indicated that B in combination with PM have the potential to improve soil properties and sweet potato yield of severely degraded soils.

High-Throughput Sequencing-Based Analysis of Rhizosphere and Diazotrophic Bacterial Diversity Among Wild Progenitor and Closely Related Species of Sugarcane (Saccharum spp. Inter-Specific Hybrids).

Considering the significant role of genetic background in plant-microbe interactions and that most crop rhizospheric microbial research was focused on cultivars, understanding the diversity of root-associated microbiomes in wild progenitors and closely related crossable species may help to breed better cultivars. This study is aimed to fill a critical knowledge gap on rhizosphere and diazotroph bacterial diversity in the wild progenitors of sugarcane, the essential sugar and the second largest bioenergy crop globally. Using a high-throughput sequencing (HTS) platform, we studied the rhizosphere and diazotroph bacterial community of Saccharum officinarum L. cv. Badila (BRS), Saccharum barberi (S. barberi) Jesw. cv Pansahi (PRS), Saccharum robustum [S. robustum; (RRS), Saccharum spontaneum (S. spontaneum); SRS], and Saccharum sinense (S. sinense) Roxb. cv Uba (URS) by sequencing their 16S rRNA and nifH genes. HTS results revealed that a total of 6,202 bacteria-specific operational taxonomic units (OTUs) were identified, that were distributed as 107 bacterial groups. Out of that, 31 rhizobacterial families are commonly spread in all five species. With respect to nifH gene, S. barberi and S. spontaneum recorded the highest and lowest number of OTUs, respectively. These results were validated by quantitative PCR analysis of both genes. A total of 1,099 OTUs were identified for diazotrophs with a core microbiome of 9 families distributed among all the sugarcane species. The core microbiomes were spread across 20 genera. The increased microbial diversity in the rhizosphere was mainly due to soil physiochemical properties. Most of the genera of rhizobacteria and diazotrophs showed a positive correlation, and few genera negatively correlated with the soil properties. The results showed that sizeable rhizospheric diversity exists across progenitors and close relatives. Still, incidentally, the rhizosphere microbial abundance of progenitors of modern sugarcane was at the lower end of the spectrum, indicating the prospect of Saccharum species introgression breeding may further improve nutrient use and disease and stress tolerance of commercial sugarcane. The considerable variation for rhizosphere microbiome seen in Saccharum species also provides a knowledge base and an experimental system for studying the evolution of rhizobacteria-host plant association during crop domestication.

Sugarcane replaced by cactus cladodes improves the ruminal dynamics of sheep

We evaluated the effect of the sugarcane replacement (Saccharum officinarum L.) by cactus cladodes (Nopalea cochenillifera Salm-Dyck) at different levels (0, 180, 360, 540 and 720 g kg-1 on a dry matter (DM) basis) in the diet of sheep on nutrient intake and digestibility, ingestive behaviour, microbial protein synthesis, nitrogen and water balance, dry matter and fibre dynamics and ruminal parameters in sheep. Five castrated male crossbred sheep, with an initial average body weight (BW) of 63.38 ± 7.70 kg, were allocated in a 5 × 5 Latin square design. The intakes of DM (P < 0.001), crude protein (CP) (P = 0.009), neutral detergent fibre content adjusted for ash and nitrogen compounds (NDFcp) (P = 0.0016), non-fibre carbohydrates (NFC) (P < 0.001), indigestible NDF (iNDF) (P = 0.0018) and total digestible nutrients (TDN) (P < 0.001) showed a quadratic effect, and the replacement levels on DM did not affect nutrient digestibility. Rumination (P = 0.001) and idle (P = 0.001) times decreased with increasing levels of cactus cladodes. Plasma urea nitrogen (PUN) (P = 0.039) increased, and there was no effect on microbial nitrogen synthesis and microbial efficiency. The pools of DM (P = 0.037), NDF (P = 0.008) and indigestible NDF (iNDF) (P = 0.010) were reduced with increasing replacement levels. The DM ingestive (P = 0.005) and degradation (P = 0.005) rates increased, and the passage rate (P = 0.049) showed a quadratic response, with a maximum value of 0.035 h-1 estimated for 44% replacement. Intake (P = 0.004), degradation (P = 0.006) and passage (P = 0.016) rates of NDF, as well as the iNDF passage rate (P = 0.014), increased. The ruminal pH (P = 0.012) reduced with increasing replacement levels. Ruminal ammonia nitrogen (NH3-N) (P = 0.020) showed a quadratic response over time, presenting an estimated maximum value of 17.9 mg dL-1 at 0.68 h after feeding. Regarding volatile fatty acids, there was an increase for acetate (P < 0.001), whereas propionate was not influenced. The butyrate (P < 0.001) concentration demonstrated a quadratic effect, with a maximum value of 14.1 mmol L-1. Replacing up to 440 g kg-1 DM of sugarcane by cactus cladodes is recommended to maximise ruminal dynamics and parameters and to improve nutrient use in sheep.

Can NO Signaling and Its Metabolism Be Used to Improve Nutrient Use Efficiency? Toward a Research Agenda.

Can NO Signaling and Its Metabolism Be Used to Improve Nutrient Use Efficiency? Toward a Research Agenda.

Saving environment through improving nutrient use efficiency under intensive use of agrochemicals in paddy fields

Increased environmental and economic costs of chemical fertilizers necessitates serious attention to improve nutrient use efficiency. A 3-year field investigation was conducted to assess the influence of different drainage systems on nitrogen (N), phosphorus (P) and potassium (K) use efficiency of two rice cultivars under alternate wetting and drying (AWD) strategy. The drying of the field was done through a surface drainage system (Control) and four subsurface drainage systems (D0.90L30, D0.65L30, D0.65L15; where D and L represent the drain depth and spacing, respectively, and Bilevel; in which the drains were spaced 15 m apart at depths 0.65 and 0.90 m). During growing seasons, the dry weight (DW) and N, P and K uptake of stem, leaf and panicle was monitored. At harvest, grain yield was also determined. Soil drying through subsurface drainage systems increased the DW of the panicle compared to surface drainage. On average, panicle DW in D0.90L30, Bilevel, D0.65L30, D0.65L15 and Control were 10.7%, 10%, 11.4%, 9.2% and 8.9% of the total DW, respectively. Improving soil aeration in the subsurface drainage systems increased crop production by increasing the share of nutrients in the panicle. The average share of N, P and K in panicle to N, P and K content of the total biomass in the subsurface-drained area was 11.7%, 12.9% and 8.4%, respectively, and in the Control was 9.7%, 10.9% and 7.9%, respectively. On average, the subsurface drainage systems improved rice grain yield and N, P and K use efficiency by 14.2% and 16%, 15% and 16% compared with Control, respectively. According to the results, subsurface drainage may effective for better aeration and increase in nutrient use efficiency in rice production systems.

The Effect of Organic Biostimulants on Beneficial Soil Microorganism Activity

Organic biostimulants and organic fertilizers can improve soil health for various horticultural crops. The objectives of these experiments were to determine if biostimulants beneficially increase soil microorganism activity in soilless medium, and additionally measure the impact of synthetic and organic fertilizers with blackstrap molasses on plant nutrient uptake nutrient runoff. It was hypothesized that the addition of biostimulants will increase soil microbe activity. Evolution of soil carbon dioxide was measured by comparing different rates (0, 15, 30, and 45 mL/3.8 L of water) of blackstrap molasses using a randomized block design with 3 replications in nursery containers. Also, a second study using St. Augustinegrass and tomatoes fertilized with organic and synthetic fertilizers was evaluated with and without a biostimulant rate (30 mL/3.8 L of water). The plants were arranged in randomized complete block design with 6 replications. Soil biostimulants did significantly increase the microorganism activity at the 0.05 level. The highest rate of blackstrap molasses improved soil biological activity over a 4-week period. Additionally, fertilizer combined with molasses did show significant increases in soil microbiology for over 5 weeks for both tomatoes and St. Augustinegrass. Molasses increased soil microbial activity but not plant nutrition. Organic fertilizer though resulted in higher levels of phosphorus, calcium, magnesium, and sulfur in plant tissue. Further research is being conducted to measure the influence of biostimulants on the breakdown of composting plant matter. Organic fertilizer slightly increased soil water pH but reduced nutrient load pollution based on a 7-day nutrient effluent study. Total nutrients (nitrates, P, Ca, Mg, and S) runoff was significantly less than synthetic fertilizer. Organic fertilizer reduced nutrient dumping in waste effluent. Organic fertilizers can improve nutrient use efficiency.

Bioinoculants-Natural Biological Resources for Sustainable Plant Production.

Agricultural sustainability is of foremost importance for maintaining high food production. Irresponsible resource use not only negatively affects agroecology, but also reduces the economic profitability of the production system. Among different resources, soil is one of the most vital resources of agriculture. Soil fertility is the key to achieve high crop productivity. Maintaining soil fertility and soil health requires conscious management effort to avoid excessive nutrient loss, sustain organic carbon content, and minimize soil contamination. Though the use of chemical fertilizers have successfully improved crop production, its integration with organic manures and other bioinoculants helps in improving nutrient use efficiency, improves soil health and to some extent ameliorates some of the constraints associated with excessive fertilizer application. In addition to nutrient supplementation, bioinoculants have other beneficial effects such as plant growth-promoting activity, nutrient mobilization and solubilization, soil decontamination and/or detoxification, etc. During the present time, high energy based chemical inputs also caused havoc to agriculture because of the ill effects of global warming and climate change. Under the consequences of climate change, the use of bioinputs may be considered as a suitable mitigation option. Bioinoculants, as a concept, is not something new to agricultural science, however; it is one of the areas where consistent innovations have been made. Understanding the role of bioinoculants, the scope of their use, and analysing their performance in various environments are key to the successful adaptation of this technology in agriculture.

Nano agrochemical zinc oxide influences microbial activity, carbon, and nitrogen cycling of applied manures in the soil-plant system

The widespread use of nano-enabled agrochemicals in agriculture for remediating soil and improving nutrient use efficiency of organic and chemical fertilizers is increasing continuously with limited understanding on their potential risks. Recent studies suggested that nanoparticles (NPs) are harmful to soil organisms and their stimulated nutrient cycling in agriculture. However, their toxic effects under natural input farming systems are just at its infancy. Here, we aimed to examine the harmful effects of nano-agrochemical zinc oxide (ZnONPs) to poultry (PM) and farmyard manure (FYM) C and N cycling in soil-plant systems. These manures enhanced microbial counts, CO2 emission, N mineralization, spinach yield and N recovery than control (unfertilized). Soil applied ZnONPs increased labile Zn in microbial biomass, conferring its consumption and thereby reduced the colony-forming bacterial and fungal units. Such effects resulted in decreasing CO2 emitted from PM and FYM by 39 and 43%, respectively. Further, mineralization of organic N was reduced from FYM by 32%, and PM by 26%. This process has considerably decreased the soil mineral N content from both manure types and thereby spinach yield and plant N recoveries. In the ZnONPs amended soil, only about 23% of the applied total N from FYM and 31% from PM was ended up in plants, whereas the respective fractions in the absence of ZnONPs were 33 and 53%. Hence, toxicity of ZnONPs should be taken into account when recommending its use in agriculture for enhancing nutrient utilization efficiency of fertilizers or soil remediation purposes.

Comparing Soil vs. Foliar Nitrogen Supply of the Whole Fertilizer Dose in Common Wheat

Late-season N application through foliar spraying is recognized as an efficient agronomic practice for improving grain quality in common wheat, although the major part of N is still supplied by soil fertilization. This study assessed the impact of various N doses entirely applied by repeated foliar sprayings on wheat growth, yield and quality, in comparison with conventional soil fertilization management with a recommended dose of 160 kg N ha−1 as ammonium nitrate (C-M). Doses of 96, 104 and 120 kg N ha−1 as both UAN (urea-ammonium-nitrate) and urea applied by foliar spraying were evaluated in a 2-year field trial in Northern Italy in a silty loam soil with 1.7% organic matter. Here, it was demonstrated that the canopy greenness was similar in all treatments, with slight grain yield increases by the lowest foliar N dose vs. C-M. The higher N foliar doses mainly improved the grain protein content and both high- and low-molecular-weight glutenin subunits (HMW-GS, LMW-GS), particularly with urea. It is concluded that in our fertile soil, managing N fertilization exclusively through foliar spraying is feasible without compromising grain yield and ameliorating quality at the same time. Improved nutrient use efficiency and beneficial environmental effects are also expected by reducing the nitrogen load on the agricultural fields by 25–40%.

Sap Analysis: A Powerful Tool for Monitoring Plant Nutrition

Horticultural crop production is moving towards an era of higher nutrient use efficiency since nutrient deficiencies can reduce plant growth, productivity, and quality, and overfertilization can cause environmental pollution. Rapid nutrient concentration diagnostic is essential to minimize the negative effects of Huanglongbing (HLB) or citrus greening in citrus by providing the required nutrients before deficiency symptoms appear, reducing the impact of the disease on crop production. Sap analysis is an additional tool for fine-tuning nutrient applications in citrus. The main objective of this paper is to review the different methodologies and results obtained with sap analysis, considering its potential application in citrus production. Results from other crops show the pros and cons of using this tool. Substantial research has been conducted on vegetables and greenhouse crops, but few studies are available on perennial species such as citrus. Inconsistency in the extraction and analysis methods and the lack of specific sufficiency ranges for citrus open the path for further studies. Along with soil and leaf analyses, sap analysis is a complementary technique that can improve nutrient use efficiency in citrus production. Moreover, sap analysis has the potential to optimize fertilizer application, minimize environmental impacts and improve sustainability.

Socio-Technical Changes for Sustainable Rice Production: Rice Husk Amendment, Conservation Irrigation, and System Changes

Rice is a staple food and primary source of calories for much of the world. However, rice can be a dietary source of toxic metal(loid)s to humans, and its cultivation creates atmospheric greenhouse gas emissions and requires high water use. Because rice production consumes a significant amount of natural resources and is a large part of the global agricultural economy, increasing its sustainability could have substantial societal benefits. There are opportunities for more sustainable field production through a combination of silicon (Si) management and conservation irrigation practices. As a Si-rich soil amendment, rice husks can limit arsenic and cadmium uptake, while also providing plant vigor in drier soil conditions. Thus, husk addition and conservation irrigation may be more effective to attenuate the accumulation of toxic metal(loid)s, manage water usage and lower climate impacts when implemented together than when either is implemented separately. This modified field production system would take advantage of rice husks, which are an underutilized by-product of milled rice that is widely available near rice farm sites, and have ~10% Si content. Husk application could, alongside alternate wetting and drying or furrow irrigation management, help resolve multiple sustainability challenges in rice production: (1) limit arsenic and cadmium accumulation in rice; (2) minimize greenhouse gas emissions from rice production; (3) decrease irrigation water use; (4) improve nutrient use efficiency; (5) utilize a waste product of rice processing; and (6) maintain plant-accessible soil Si levels. This review presents the scientific basis for a shift in rice production practices and considers complementary rice breeding efforts. It then examines socio-technical considerations for how such a shift in production practices could be implemented by farmers and millers together and may bring rice production closer to a bio-circular economy. This paper's purpose is to advocate for a changed rice production method for consideration by community stakeholders, including producers, millers, breeders, extension specialists, supply chain organizations, and consumers, while highlighting remaining research and implementation questions.

Effect of Substrate Flow Rate on Nutrient Uptake and Use Efficiency in Hydroponically Grown Swiss Chard (Beta vulgaris L. ssp. cicla ‘Seiyou Shirokuki’)

Unlike in soil culture, a substrate (nutrient solution) in a hydroponics system can flow, and this can affect both nutrient uptake and plant growth. In this study, we hydroponically cultivated Swiss chard (Beta vulgaris L. ssp. cicla) under different flow rates to analyze changes in the growth, nutrient uptake, and nutrient use efficiency. When the flow rate was intensified from 2 to 4 L/min, leaf area, the fresh weight, dry weight, and root length increased. However, when the flow rate was increased from 4 to 8 L/min, values of these growth parameters decreased. The nutrient uptake had a similar trend relative to the growth parameters and nutrient use efficiency of macronutrient elements, increased as the flow rate increased. This indicates that the flow rate affects plant growth by influencing the nutrient uptake, and an increase in the flow rate can aid in improving nutrient use efficiency. In hydroponics, regulating the flow rate at a reasonable volume is recommended to increase yield by enhancing nutrient use efficiency, but too intensive a flow rate may cause excessive physical stimulation to plants and inhibit their growth. Therefore, it is important to choose an appropriate substrate flow rate for optimal hydroponics production.

Balanced Fertilization for Improved Nutrient use Efficiency and Mulberry Productivity

Aim: To study the effects of balanced fertilization in improving leaf yield, quality and nutrient use efficiency in mulberry.&#x0D; Study Design: Experiment was conducted in randomized block design (RBD) consisting of 7 treatments in 3 replications.&#x0D; Place and Duration of Study: The present study was conducted at Central Sericultural Research and Training Institute, Berhampore ((Latitude 24º05ʹN &amp; Longitude 88º15ʹE; 18 m &gt; MSL), West Bengal, India in two seasons during 2018 (July-August; September-October).&#x0D; Methodology: Existing S-1635 mulberry plantation (10year-old; 60 cm × 60 cm spacing; net plot area: 32 m2) was utilized. Experiments were conducted in two seasons (July-August, 2018; September-October, 2018) in randomized block design (RBD) consisting of 7 treatments in 3 replications. The treatments in this study included, T1: 100% N-P2O5-K2O+S+Zn with Urea-SSP-10:26:26 + Bentonite Sulphur (8 kg ha-1) + Zinc Sulphate (1 kg ha-1) as BF; T2: 75% BF; T3: 100% N-P2O5-K2O alone (Urea-SSP-10:26:26); T4: 75% N-P2O5-K2O alone (Urea-SSP-10:26:26); T5: 100% N-P2O5-K2O alone (Urea-DAP-MOP); T6: 100% N-P2O5-K2O alone (Urea-SSP-MOP) as farmers′ practice (FP); T7: Nutrients omission plot (Control). The recommended fertilizer dose (100%) for irrigated mulberry production in the Eastern region is N-P2O5-K2O=67-36-22 kg ha-1 crop-1. All the fertilizers were applied in two equal splits on 15th and 30th day after pruning.&#x0D; Results: This study reveals the importance of balanced fertilization of mulberry with N, P, K, S and Zn for sustainable productivity, which is reflected by the maximum values for leaf yield attributes, chlorophyll content and leaf yield. Further, mulberry leaf quality (in terms of total soluble protein and total soluble sugar) significantly improved with balanced fertilization. Higher PFP and AUE were also recorded with fertilization with compound/complex fertilizers than with straight fertilizers; but the balanced fertilization exhibited remarkable enhancement.&#x0D; Conclusion: The results prove that balanced fertilization of N-P2O5-K2O @ 67-36-22 kg ha-1 (Urea-SSP-10:26:26) with Bentonite sulphur (8 kg ha-1) and zinc sulphate (1 kg ha-1) were effective in improving mulberry productivity through enhanced nutrient use efficiency. This could be useful for realizing maximum productivity in mulberry as an efficient nutrient management strategy in mulberry cultivation.

Late Gestation Maternal Feed Restriction Decreases Microbial Diversity of the Placenta While Mineral Supplementation Improves Richness of the Fetal Gut Microbiome in Cattle.

Simple SummaryThe purpose of this study was to explore the influence of maternal feed intake restriction on the microbiome of the reproductive tract and its subsequent colonization of the bovine fetal gut microbiome in utero. After sequencing the microbial DNA of the maternal vagina, placental tissues, and fetal gut, our data show the microbiome of the vagina and cotyledon remain relatively unaffected by feed intake restriction and mineral supplementation. The placental microbiome of feed restricted pregnancies was less diverse, and feeding using a mineral supplement did not impact these differences. However, mineral supplementation improved the richness of the fetal gut microbiomes regardless of feeding treatment, substantiating prior evidence that in utero mineral supplementation improves calf performance. The obtained results may offer insight into improving nutrient use of calves born to dams experiencing feed restriction.Feed intake restriction impacts both humans and ruminants in late gestation, although it is unknown whether this adverse maternal environment influences the microbiome of the reproductive tract, and through it, the colonization of the fetal gut. A 2 × 2 factorial design including a 70% feed intake restriction (feed restricted ‘FR’ or control diets ‘CON’) and mineral supplementation (unsupplemented ‘S−’ or supplemented ‘S+’) was used to analyze these effects in multiparous cows (n = 27). Vaginal swabs were obtained 60, 30, and 10 days prior to the estimated calving date, along with neonatal rumen fluid and meconium. Placental tissues and efficiency measurements were collected. Microbial DNA was extracted for 16S sequencing of the V4 region. Feed restriction decreased the diversity of the placental microbiome, but not the vagina, while mineral supplementation had little impact on these microbial communities. Mineral supplementation did improve the richness and diversity of the fetal gut microbiomes in relation to reproductive microbes. These differences within the placental microbiome may influence individual health and performance. Adequate maternal nutrition and supplementation yielded the greatest placental efficiency, which may aid in the establishment of a healthy placental microbiome and fetal microbial colonization.

Influence of potassium fertilization on yield, petiole and soil nutrient status of table grape cv. Sharad seedless

Potassium (K) is one of the important essential elements for vine growth and yield. Grape growers are applying fertilizers through soil and also through fertigation. But, the information on to what extent they can apportion the fertilizer application through these methods to improve nutrient use efficiency is not available. Present investigation aimed to study the influence of combined application of different sources of potassium and their method of application on yield, soil and petiole-nutrient status for two consequitive years. Pooled analysis revealed that yield and major nutrients were affected significantly (P < 0.05) by the different treatments. Grapevines fertilized with 40% KNO3 (potassium nitrate) through fertigation + 60% SOP (Sulfate of Potash) through soil showed significantly highest yield vine-1 (7.00 kg). Leaf petiole analysis revealed that potassium applied at different combination caused wide variation in leaf petiole contents of N, K, Ca and Mg. The vines which received 40% SOP through fertigation + 60% SOP through soil had recorded highest potassium and lowest nitrogen, calcium and magnesium contents in petioles. The vines which supplied with 100% SOP through fertigation showed least petiole potassium content. Application of SOP through both fertigation and soil at different doses significantly increased available soil potassium compared to potassium supplied through fertigation and/or soil alone. There was significant negative correlation between potassium and calcium (r= −0.914) and potassium and magnesium (r= − 0.733) in soil.

Soil spatial variability characterization: Delineating index-based management zones in salt-affected agroecosystem of India

Farm level recommendation in salt-affected agricultural landscapes is practically difficult due to spatial variations in inherent soil salinity, diverse farming situations and associated land ownerships with small-scale production systems. This study presents spatial array analysis of 354 geo-referenced soil samples revealing widespread heterogeneity in soil sodicity and fertility status across salt-affected Ghaghar basin of Kaithal district in Haryana, India. Six principal components accounted for 73% of the total variability, and the most important contributors [electrical conductivity (ECe), sodium adsorption ratio (SAR), DTPA extractable copper (Cu) and boron (B), soil organic carbon (OC) and available phosphorus (AP)] as minimum data set were used to develop the soil quality index (SQI). Geostatistical analysis revealed Circular (ECe and AP), Exponential (SAR, OC and B) and Gaussian (Cu) as the best fit semivariogram ordinary kriging model with weak to moderate spatial dependence. Three soil management zones (SMZs) were delineated by grouping the entire area based on soil quality index (SQI). Fertilizer recommendations for rice-wheat cropping system in different SMZs were calculated using soil test crop response (STCR) equation to ensure balanced fertilization, resource saving and reducing environmental footprints. Gypsum requirement map was prepared for systematic allocation and distribution, and enabling farmers to precisely use the mineral gypsum in order to reclaim and reduce stresses led by sodic lands. The implications of this study showed zone-specific advocacy for gypsum application (as soil ameliorant) and balanced fertilization in sustainable restoration of sodic lands, improving nutrient use efficiency and stabilizing crop production in salt-affected regions of India and similar ecologies elsewhere.