Nitrogen-molybdenum-manganese co-fertilization reduces nitrate accumulation and enhances spinach (Spinacia oleracea L.) yield and its quality

Spinach (Spinacia oleracea L.) is considered a nitrogen (N) intensive plant with high nitrate (NO₃^?) accumulation in its leaves. The current study via a two-year field trial introduced an approach by combining N fertilization from different sources (e.g., ammonium nitrate; 33.5 % N, and urea; 48 % N) at different rates (180, and 360 kg N ha^?1) with the foliar spraying of molybdenum (Mo) as sodium molybdate, and/or manganese (Mn) as manganese sulphate at rates of 50 and 100 mgL^?1 of each or with a mixture of Mo and Mn at rates of 50 and 50 mg L^?1, respectively on growth, chemical constituents, and NO₃^? accumulation in spinach leaves. Our findings revealed that the highest rate of N fertilization (360 kg N ha^?1) significantly increased most of the measured parameters e.g., plant length, fresh and dry weight plant^?1, number of leaves plant^?1, leaf area plant^?1, leaf pigments (chlorophyll a, b and carotenoids), nutrients (N, P, K, Fe, Mn, Zn), total soluble carbohydrates, protein content, net assimilation rate, and NO₃^? accumulation, but decreased leaf area ratio and relative growth rate. Moreover, plants received urea-N fertilizer gave the highest values of all previous attributes when compared with ammonium nitrate –N fertilizers, and the lowest values of NO₃^? accumulation. The co-fertilization of N-Mo-Mn gave the highest values in all studied attributes and the lowest NO₃^? accumulation. The best treatment was recorded under the treatment of 360 kg N-urea ha^?1 in parallel with the combined foliar application of Mo and Mn (50 + 50 mg L^?1). Our findings proposed that the co-fertilization of N-Mo-Mn could enhance spinach yield and its quality, while reducing NO₃^? accumulation in leaves, resulting agronomical, environmental and economic benefits.     

Application of homobrassinolide enhances growth,yield and quality of tomato

Brassinosteroids (BRs) have emerged as pleiotropic phytohormone owing to their wide function in crop growth and metabolism. Homobrassinolide (HBR) being an analogue of BRs is known to improve the growth, yield and quality parameters in many crop plants. Thus, an evaluation study was conducted for two years (2018 and 2019) to elucidate the performance of tomato plants (Solanum lycopersicum L.) to a novel group of phytohormone,HBR. The field experiment comprised of seven treatments with homobrassinolide 0.04% (Emulsifiable Concentrate) EC at four different concentrations (0.06, 0.08, 0.10 and 0.12 g active ingredient (a.i.) ha^?1) and two well-known growth promoters viz., Gibberellic acid (GA), Naphthalene Acetic Acid (NAA) along with the untreated control. Plant height and chlorophyll concentration were found significantly different in both years of experiment as well as among the different treatments. HBR at 0.12 g a.i. ha^?1 was found better with maximum number of fruits (77.36 plant^?1), fruit length (6.72 cm), fruit breadth (6.45 cm) and fruit weight (80.52 g) over other concentrations and treatments. Fruit yield was more pronounced in the plots treated with plant growth regulators compared to untreated control. However, significantly higher fruit yield of 91.07 t ha^?1 (62.58 t ha^?1 with untreated control) along with improved quality traits viz., fruit firmness (4.11 kg cm^?2), ascorbic acid content (24.09 mg 100 g^?1), total soluble solids (4.43°Brix) and keeping quality (12.50 days) was recorded in 0.12 g a.i. ha^?1 HBR treated plots. Thus, it can be inferred that HBRapplication would be a better option to enhance growth, yield as well as quality traits in tomato.     

Exogenous Glutathione Modulates Salinity Tolerance of Soybean [<Emphasis Type="Italic">Glycine max</Emphasis> (L.) Merrill] at Reproductive Stage

In this study, we evaluated salt stress responses of 11 soybean genotypes and explored the protective roles of exogenous glutathione (GSH) against salt toxicity by assessing various biochemical and yield-attributing parameters. Exposure of the soybean genotypes to salt stress at the reproductive (R1) stage significantly decreased their yields by down-regulating the yield-contributing parameters as compared with unstressed controls. The highest decrease was found in number of seeds plant^?1, yield plant^?1, and number of pods plant^?1, whereas the lowest decrease was recorded in number of seeds pod^?1. Exogenous GSH was found to be effective in improving salinity tolerance, and the highest positive effects of GSH were recorded in terms of yield plant^?1, number of seeds plant^?1 and number of pods plant^?1, whereas its lowest effect was observed with respect to the 100-seed weight. Cluster analysis of the genotypes based on yield-contributing and yield data revealed different levels of salt tolerance. Notably, BINA-01 and -02, and BINA-04 were recognized as the highest and lowest salt-tolerant genotypes, respectively. Furthermore, exogenous GSH alleviated oxidative stress in the representative contrasting genotypes at the vegetative (V3) stage by decreasing salt-induced accumulation of malondialdehyde and hydrogen peroxide. Taken together, our findings revealed that exogenous GSH application can minimize oxidative stress and contribute to the improvement of yield-contributing parameters, leading to improved yield in soybean genotypes under salt stress. Further investigations on molecular aspects will enable us to gain an in-depth understanding of how exogenous GSH can improve salinity tolerance in soybean, particularly at reproductive stage, to discover relevant pathways for biotechnological manipulation.     

High efficiency plant regeneration and genetic fidelity of regenerants by SCoT and ISSR markers in chickpea (Cicer arietinum L.)

High efficient and repeatable in vitro regeneration protocol was established from embryo axis, half-seed, axillary meristem, and cotyledonary node explants of chickpea. Various concentrations and combinations of various plant growth regulators (PGRs) were employed to induce multiple shoots, shoot elongation and rooting of shoots to obtain complete plantlets of chickpea. The pretreatment of seeds with 6-benzyl aminopurine (BAP) at 1.0 mg l^?1 was found to significantly increase the multiple shoot regeneration from the all explants tested. Among three PGRs such as BAP, kinetin (KIN) and thidiazuron (TDZ) tested for multiple shoot induction; BAP at 2.0 mg l^?1 produced the maximum number of shoots in all tested explants. The maximum number of shoots (48.80 shoots/explant) was attained from the embryo axis explant followed by half-seed (32.76 shoots/explant), axillary meristem (28.34 shoots/explant) and cotyledonary node explant (18.47 shoots/explant) on medium augmented with 2.0 mg l^?1 BAP along with 0.05 mg l^?1 Indole-3-butyric acid (IBA). The optimum percentage of shoot elongation response was recorded (96.68%) on medium fortified with IAA (0.05 mg l^?1), GA₃ (1.0 mg l^?1) and BAP (1.0 mg l^?1) with an average shoot length of 8.82 cm. The elongated shoots were successfully rooted in medium augmented with 2.0 mg l^?1 IBA. The complete plants were acclimatized in the greenhouse with a survival rate of 72%. The plantlets regenerated from four explants appeared to be morphologically similar to mother plants. The genetic fidelity of in vitro regenerated plants was evaluated using Start Codon Targeted and Inter simple sequence repeats molecular markers. The in vitro regenerated plants from all four explants were found to be the true to type with their mother plant. The in vitro protocol presented in the study should offer as a feasible system for chickpea genetic transformation.

     

Synergy between parasitoids and pathogens for biological control of Helicoverpa armigera in chickpea

The chickpea pod borer, Helicoverpa armigera Hübner (Lepidoptera: Noctuidae), is an important pest of many legume crops, including chickpea, Cicer arietinum L. (Fabaceae). We field-tested the efficacy of two pathogens, Helicoverpa armigera nucleopolyhedrosis virus (HaNPV) and Bacillus thuringiensis Berliner subsp. kurstaki (Btk), both alone and in combination with the parasitoid Habrobracon hebetor Say (Hh) (Hymenoptera: Braconidae), for control of H. armigera larvae in chickpea fields. A randomized complete block design was used at two sites, so that wasp release treatments at one site would not contaminate pathogen-only treatments at the other. Pathogens were applied when most pest larvae were in the second instar, and wasp releases were made 2 days later. Number of H. armigera larvae per plant, number of damaged pods, yield (kg ha⁻¹), treatment cost (US$ ha⁻¹), and benefit:cost ratio were all determined. Treatments separated significantly at 14 days after treatment, with the HaNPV+Hh and Btk+Hh treatments providing the best control, suggesting a synergistic impact of the wasp and the pathogens when applied together. These treatments also produced the fewest damaged pods, the highest yields, and the greatest yield increments in comparison to untreated controls. However, costs were also highest for these combined treatments, which reduced their net benefit in comparison to use of Hh or Btk alone, although more efficient mass production of the pathogens might make combined applications feasible. We conclude that both HaNPV and Btk are suitable for integration with releases of H. hebetor against H. armigera in chickpea fields, provided parasitoid releases are delayed until 2 days after pathogen application.     

Physiological,biochemical and molecular evaluation of mungbean genotypes for agronomical yield under drought and salinity stresses in the presence of humic acid

Drought and salinity are potential threats in arid and semi arid regions. The current study was conducted with objective to optimize the production of different exotic genotypes of mungbean (NM-121-25, Chakwal M-6, DM-3 and PRI-Mung-2018) under drought and salinity stresses using humic acid in field experiments. One year tri-replicate field experiment was performed in RCBD using three factorial arrangement and effects of humic acid (60 kg ha^?1) were evaluated at physiological, biochemical, molecular and agronomical level under individual and integrated applications of drought (no irrigation till 15 days) and salinity (EC 6.4 dSM^?1). Data for physiological parameters (total chlorophyll, photosynthesis rate, stomatal conductance, transpiration rate and membrane damage), antioxidant enzymes (superoxide dismutase, catalase, peroxidase) and proline were collected on weekly basis since after the initiation of drought and salinity stresses. However data for agronomic characteristics (plant height, branches plant^?1, LAI, pods plant^?1, pod length and hundred seed weight) and grain carbohydrate content were collected after harvesting, while sampling for drought (VrDREB2A, VrbZIP17 and VrHsfA6a) and salinity (VrWRKY73, VrUBC1 and VrNHX1) related genes expression study was done after plants attained seedling stage. Under both individual and integrated applications of drought and salinity, all genotypes showed significant (p ≤ 0.05) increase in all traits excluding Cell membrane damage and proline during humic acid application. Likewise, genes expression revealed statistically distinct (p ≤ 0.05) up-regulation under humic acid treatment as compared to no humic acid treatment during both individual and integrated applications of drought and salinity. The genotype PRI-Mung-2018 recorded noteworthy performance during study. Moreover correlation and PCA analysis revealed that ultimate agronomical yield due to humic acid is an outcome of interconnection of physiological and biochemical parameters.     

Application of zeolite improves water and nitrogen use efficiency while increasing essential oil yield and quality of Salvia officinalis under water-deficit stress

Soil moisture and nitrogen (N) are two of the most important factors affecting the production of medicinal plants. So, the management strategy of these factors is critical and to be identified. In order to study the application of zeolite (Z) (0 and 10 ton ha^?1) in S. officinalis culture medium under different irrigation regimes (30 % depletion of available soil water (ASW)) and 60 % depletion of ASW) and N (0, 75 and 150 kg N ha^?1) a split-factorial experiment was carried out with three replicates in 2018. The highest fresh and dry weight were achieved at irrigation after 30 % depletion of ASW while using 150 kg N ha^?1 and 10 ton Z ha^?1. Maximum water use efficiency (WUE) (22.10 g.L^-1) was obtained after 60 % depletion of ASW and 150 kg N ha^?1 and 10 ton Z ha^?1. Besides, the maximum nitrogen use efficiency (NUE) was obtained after 60 % depletion of ASW and 75 kg N ha^?1 and 10 ton Z ha^?1 (14.25 kg.kg^-1N). Maximum essential oil (EO) content (1.06%) and cis-Thujone were obtained from plants subjected to 60 % depletion of ASW and, application of 75 kg N ha^?1 and 10 ton Z ha^?1. Applying Z with N, in different irrigation regimes did improve soil conditions for achieving higher, WUE and NUE, increased the EO content and yield while decreasing the negative effects from water-deficit stress and has provided a direction towards a stable system.     

Effects of Mechanized,Deep Application of Slow-Release Fertilizer on Yield and Nitrogen,Phosphorus, and Potassium Utilization of Direct-Seeded Rice

Compared with the standard method of manual fertilizer broadcasting (MFB), mechanized hill-drilling direct-seeding with deep application of slow-release nitrogen fertilizer (MHDDF) is an efficient method to integrate both fertilization and seeding. However, there are few studies that combine the use of slow-release fertilizer with MHDDF. We sought to explore the combined effect of MHDDF with slow-release fertilizer on rice yield and nitrogen, phosphorus, and potassium utilization, compared to MFB. We compared three different MHDDF methods (D30: 450 kg ha^?1, D40: 600 kg ha^?1, D50: 750 kg ha^?1), with one MFB method (B50: 750 kg ha^?1), and one control (CK: 0 kg ha^?1). We found that the yield of all MHDDF method was higher than that of both the MFB method. Yield was the highest in the D50 treatment and was 14.14–46.03% higher than that in B50 treatment. Biomass accumulation, nutrient accumulation, and nutrient use efficiency were similarly higher in MHDDF method than both MFB and CK. Compared to B50, the D50 treatment increased nitrogen recovery efficiency by 170.53–231.50%, phosphorus recovery efficiency by 480.00–724.25%, and potassium recovery efficiency by 201.55–169.59%. Overall, we found that combining MHDDF with slow-release fertilizer was an effective method to increase rice yield and nutrient use efficiency compared with MFB.

     

Regulation of Nitrogen Metabolism,Photosynthetic Activity,and Yield Attributes of Spring Wheat by Nitrogen Fertilizer in the Semi-arid Loess Plateau Region

It is critical for spring wheat (Triticum aestivum L.) production in the semi-arid Loess Plateau to understand the impact of nitrogen (N) fertilizer on changes in N metabolism, photosynthetic parameters, and their relationship with grain yield and quality. The photosynthetic capacity of flag leaves, dry matter accumulation, and N metabolite enzyme activities from anthesis to maturity were studied on a long-term fertilization trial under different N rates [0 kg ha^?1(N1), 52.5 kg ha^?1 (N2), 105 kg ha^?1 (N3), 157.5 kg ha^?1 (N4), and 210 kg ha^?1 (N5)]. It was observed that N3 produced optimum total dry matter (5407 kg ha^?1), 1000 grain weight (39.7 g), grain yield (2.64 t ha^?1), and protein content (13.97%). Our results showed that N fertilization significantly increased photosynthetic parameters and N metabolite enzymes at all growth stages. Nitrogen harvest index, partial productivity factor, agronomic recovery efficiency, and nitrogen agronomic efficiency were decreased with increased N. Higher N rates (N3–N5) maintained higher photosynthetic capacity and dry matter accumulation and lower intercellular CO₂ content. The N supply influenced NUE by improving photosynthetic properties. The N3 produced highest chlorophyll content, photosynthetic rate, stomatal conductance and transpiration rate, grain yield, grain protein, dry matter, grains weight, and N metabolite enzyme activities compared to the other rates (N1, N2, N4, and N5). Therefore, increasing N rates beyond the optimum quantity only promotes vegetative development and results in lower yields.

     

Gamma rays induced genetic variability in tomato (Solanum lycopersicum L.) germplasm

The present study assessed the effectiveness of gamma radiation in inducing favorable genetic variability in tomato (Solanum lycopersicum L.). An experiment was conducted in a randomized complete block design to produce M₁ generation. Significant differences were observed among the genotypes as well as between the treatments at individual plant level based on observed traits (seed germination percentage, seedling survival, plant height, number of flower clusters plant^?1, number of flowers and fruits plant^?1). All observed characters in the mutagenized population were adversely affected with increasing radiation dose. Results identified 450 Gy as the most damaging radiation dose followed by 300 Gy and 150 Gy. Moreover, 300 Gy treatment was identified as lethal dose (LD₅₀) as it caused a 50% germination inhibition in almost all the evaluated genotypes. The 150 Gy treatment showed the least damaging impact and induced maximum genetic variability in almost all the genotypes under study. Character association studies were also conducted which could be utilized in the selection of desirable mutants. Correlation studies revealed an altered association among the observed parameters from positive to negative direction in 300 Gy and 450 Gy treatments as compared to control. These deviations in correlation coefficients proved that mutagenesis can break the linkage among specific loci. Furthermore, path coefficient analysis identified the growth attributes with an effective direct and indirect contribution in yield.     

Biochar in Combination with Nitrogen Fertilizer is a Technique: To Enhance Physiological and Morphological Traits of Rice (Oryza sativa L.) by Improving Soil Physio-biochemical Properties

The over use of synthetic nitrogen (N) fertilizers is the major anthropogenic cause of low N-use efficiency and environmental damage in wetland rice production. Biochar (B) addition to soil is suggested as a climate change mitigation tool that supports carbon sequestration and reduces N losses and greenhouse gas emissions from the soil. Therefore, this study assessed the effect of four levels of B (0, 10, 20 and 30 t ha^?1) combined with two levels of N (135 and 180 kg ha^?1) on soil health, roots dynamics, physiological attributes, and yield components of rice. The addition of B at 30 t ha^?1 combined with 135 N kg ha^?1 increased chlorophyll content, net photosynthetic rate, biomass, and grain yield by 104%, 64%, 12%, and 30%, respectively, over control. Further, root traits such as total root length (TRL), total root volume (TRV), total root surface area (TRSA), and total average root diameter (TARD) were improved under 30 t ha^?1 combined with 135 N kg ha^?1 by 20%, 13%, 13%, and 25%, respectively, than non-biochar treatment under lower N application. Improvements in these traits resulted from higher N uptake due to improved soil physiochemical properties and soil microbial biomass combined with biochar. Interestingly, enhanced N metabolizing enzyme activities, including nitrate reductase (NR), glutamine synthetase (GS), and glutamine oxoglutarate aminotransferase (GOGAT) in biochar-treated plots, further supported the increases in these traits. Our results revealed that the integration of 30 t B ha^?1 with 135 kg N ha^?1 is a favorable option for enhancing soil health and rice grain yield.

     

Enhancing water use efficiency and grain yield of wheat by optimizing irrigation supply in arid and semi-arid regions of Pakistan

The lack of good irrigation practices and policy reforms in Pakistan triggers major threats to the water and food security of the country. In the future, irrigation will happen under the scarcity of water, as inadequate irrigation water becomes the requirement rather than the exception. The precise application of water with irrigation management is therefore needed. This research evaluated the wheat grain yield and water use efficiency (WUE) under limited irrigation practices in arid and semi-arid regions of Pakistan. DSSAT was used to simulate yield and assess alternative irrigation scheduling based on different levels of irrigation starting from the actual irrigation level up to 65% less irrigation. The findings demonstrated that different levels of irrigation had substantial effects on wheat grain yield and total water consumption. After comparing the different irrigation levels, the high amount of actual irrigation level in semi-arid sites decreased the WUE and wheat grain yield. However, the arid site (Site-1) showed the highest wheat grain yield 2394 kg ha^?1 and WUE 5.9 kg^?3 on actual irrigation (T₁), and with the reduction of water, wheat grain yield decreased continuously. The optimal irrigation level was attained on semi-arid (site-2) with 50% (T₁₁) less water where the wheat grain yield and WUE were 1925 kg ha^?1 and 4.47 kg^?3 respectively. The best irrigation level was acquired with 40% less water (T₉) on semi-arid (site-3), where wheat grain yield and WUE were 1925 kg ha^?1 and 4.57 kg^?3, respectively. The results demonstrated that reducing the irrigation levels could promote the growth of wheat, resulting in an improved WUE. In crux, significant potential for further improving the efficiency of agricultural water usage in the region relies on effective soil moisture management and efficient use of water.     

Morpho-Biochemical characterization of Kalazeera (Bunium persicum Boiss. Fedts) germplasm grown in Global temperate ecologies

The present investigation explores the variability of Bunium persicum populations belonging to different regions. Variability among 74 genotypes for thirty-seven traits (29 quantitative and 8 qualitative) were studied to ascertain the population structure of the Bunium persicum. Among the agro-morphological traits, wide range of variability was recorded in tuber shape, tuber colour, seed shape, seed colour, growth habit, leaf shape, leaf colour, umbel shape, umbel colour, plant height (22.90–96.52 cm), primary branches plant⁻¹ (1–6), umbel diameter of primary umbel (6.17 – 13.67 cm), number of primary umbels plant⁻¹ (1–12), umbels plant⁻¹ (8–40), seed yield per plant (0.55–13.10 g), essential oil content (3.2–9.3 %) etc. Significant and positive association was observed between number of seeds primary^-1 umbel (r = 0.91), plant height (r = 0.65), number of seeds primary^-1 umbel (0.52), number of seeds primary^-1 umbel (0.43), number of seeds secondary^-1 umbel (0.38) with number of umblets secondary^-1 umbel. Cluster analysis classified the genotypes with different geographical origin into two major clusters and sub-clusters. Cluster-I comprises of 50 genotypes and cluster - II of 24 genotypes while the genotype SRS-KZ-189 from Kargil population was separated as an individual sub-group. Principal component (PC1) and (PC2) harbors accounted 20.2% and 14% of total variation. Variability of Kalazeera genotypes would facilitate the plant breeders to implement and design various crop improvement programme in future.     

Phytoremediation potential of some halophytic species for soil salinity

Phytoremediation potential of six halophytic species i.e. Suaeda nudiflora, Suaeda fruticosa, Portulaca oleracea, Atriplex lentiformis, Parkinsonia aculeata and Xanthium strumarium was assessed under screen house conditions. Plants were raised at 8.0, 12.0, 16.0, and 20.0 dSm^?1 of chloride-dominated salinity. The control plants were irrigated with canal water. Sampling was done at vegetative stage (60–75 DAS). About 95 percent seed germination occurred up to 12 dSm^?1 and thereafter declined slightly. Mean plant height and dry weight plant^?1 were significantly decreased from 48.71 to 32.44 cm and from 1.73 to 0.61g plant^?1 respectively upon salinization. Na⁺/K⁺ ratio (0.87 to 2.72), Na⁺/ Ca²⁺ + Mg²⁺ (0.48 to 1.54) and Cl^?/SO₄^2– (0.94 to 5.04) ratio showed increasing trend. Salinity susceptibility index was found minimum in Suaeda fruticosa (0.72) and maximum in Parkinsonia aculeata (1.17). Total ionic content also declined and magnitude of decline varied from 8.51 to 18.91% at 8 dSm^?1 and 1.85 to 7.12% at 20 dSm^?1 of salinity. On the basis of phytoremediation potential Suaeda fruticosa (1170.02 mg plant^?1), Atriplex lentiformis (777.87 mg plant^?1) were the best salt hyperaccumulator plants whereas Xanthium strumarium (349.61 mg plant^?1) and Parkinsonia aculeata (310.59 mg plant^?1) were the least hyperaccumulator plants.     

Sugar metabolism and partitioning in cytosol and bacteroid fractions of chickpea nodules

The contents of free sugars in nodules of chickpea (Cicer arietinum) were maximum around flowering. In stem and root tissues, the relative incorporation of ¹⁴C from [¹⁴C]-labelled sucrose or glucose into extracted sucrose was over 70 %. In the former tissue, the relative incorporation of ¹⁴C from glutamate into sucrose was about 50 % at 50 d after sowing (DAS) but the same decreased to about 25 % at 80 DAS. However, from glutamate, 63–68 % of ¹⁴C from extracted sugars of root tissue appeared in invert sugars. Feeding via stem [¹⁴C]-glutamate to intact nodules led to intense labelling of sucrose and invert sugars in nodule cytosol. Upon injecting labelled sugars or glutamate into isolated nodules, maximum ¹⁴C appeared in glucose of this nodule fraction. In bacteroids, incorporation of ¹⁴C from glutamate was much higher in amino acids. In the cytosol of younger (50 DAS) nodules, sucrose was cleaved largely by soluble alkaline invertase (EC 3.2.1.26). However, sucrose cleavage in this fraction of older (80 DAS) nodules was catalysed by this enzyme as well as sucrose synthase (reversal, EC 2.4.1.13) and such nodules also contained higher activity of nitrogenase. The bacteroid fraction, which contained 10–17 % of nodule sugars, lacked the activities of sucrose-cleaving enzymes. The activities of ATP-dependent phosphofructokinase (EC 2.7.1.11), glyceraldehyde-3-phosphate dehydrogenase (EC 1.1.1.12), NADP⁺-dependent isocitrate dehydrogenase (EC 1.1.1.41) and malate dehydrogenase (EC 1.1.1.37) were higher in cytosol than bacteroids. However, the reverse was true for glucose-6-phosphate dehydrogenase (EC 1.1.1.49) and 6-phosphogluconate dehydrogenase (EC 1.1.1.44). The results suggest that in chickpea nodules sugar metabolism occurs largely via the glycolytic pathway in cytosol and the pentose phosphate pathway in bacteroids and there is some transport of glutamate from cytosol to bacteroids.     

Improvement of growth,under field conditions,of wheat inoculated with <Emphasis Type="Italic">Pseudomonas chlororaphis</Emphasis> subsp.<Emphasis Type="Italic"> aurantiaca</Emphasis> SR1

Effects of inoculation of wheat (Triticum aestivum L.) with the rhizobacterium Pseudomonas chlororaphis subsp. aurantiaca strain SR1 (termed SR1) were studied at an experimental field site in Río Cuarto, Argentina. Treatments involved SR1 inoculation with or without nitrogen/phosphorus fertilization. Inoculation produced a significant increase in plant height and root length in early growth stages. Inoculation plus fertilization with 40 kg ha⁻¹ urea/30 kg ha⁻¹ diamonic phosphate (“50% dose”) gave a yield increase of 636 kg ha⁻¹ relative to control, and an increase of 472 kg ha⁻¹ relative to fertilization with 80 kg ha⁻¹ urea/60 kg ha⁻¹ phosphate without inoculation. SR1 inoculation without fertilization, compared to control, produced increases of 6% in weight of 1,000 grains, 13% in number of spikes per plant, and 30% in number of grains per spike. Inoculation plus 50% dose fertilization also improved these parameters. Results of the study indicate that inoculation of wheat with SR1 improves various growth and yield parameters, and allows reduced dosage of nitrogen/phosphorus fertilizers in the field.     

Response of Arbuscular Mycorrhizal Fungi on Wheat (Triticum aestivum L.) Grown Conventionally and on Beds in a Sandy Loam Soil

The present study was undertaken to assess the benefit and compare the functioning of AM fungi on wheat grown conventionally and on beds. Ten treatment combinations were used, treatments 1 and 2: no fertilizers with and without arbuscular mycorrhizal (AM) fungi (In vitro produced Glomus intraradices); 3:100% of recommended NPK: (120 kg ha⁻¹ N; 60 kg ha⁻¹ P; 50 kg ha⁻¹ K), and 4 and 5: 75% of recommended NPK dose with and without AM inoculation in a 5 × 2 split-plot design on wheat using conventional/flat system and elevated/raised bed system. The maximum grain yield (3.84 t ha⁻¹) was obtained in AM fungi inoculated plots of raised bed system applied with 75% NPK and was found higher (although non- significant) than the conventional (3.73 t ha⁻¹) system. The AM inoculation at 75% fertilizer application can save 8.47, 5.38 kg P and 16.95, 10.75 kg N ha⁻¹, respectively, in bed and conventional system. While comparing the yield response with 100% fertilizer application alone, AM inoculation was found to save 20.30, 15.79 kg P and 40.60, 31.59 kg N ha⁻¹, respectively, in beds and conventional system. Mycorrhizal inoculation at 75% NPK application particularly in raised bed system seems to be more efficient in saving fertilizer inputs and utilizing P for producing higher yield and growth unlike non-mycorrhizal plants of 100% P. Besides the yield, mycorrhizal plants grown on beds had higher AM root colonization, soil dehydrogenases activity, and P-uptake. The present study indicates that the inoculation of AM fungi to wheat under raised beds is better response (although non-significantly higher) to conventional system and could be adopted for achieving higher yield of wheat at reduced fertilizer inputs after field validation.     

Standardization of in vitro micropropagation of Winter Jasmine (Jasminum nudiflorum) using nodal explants

Present investigation was carried out to arrive at an effective micropropagation protocol for Winter Jasmine (Jasminum nudiflorum) using nodal segments from actively growing plants as explants. Explants were collected from current season shoots during April-May just after the initiation of new flush. Combined sterilization treatment of explants with 1.0% NaOCl₂ for 10 min followed by 70% ethanol for 10 s recorded highest culture survival (63.88%) and optimum culture asepsis (63.88%) followed by the treatment containing 0.1% HgCl₂ for 10 min followed by 70% ethanol for 10 s with culture survival (61.11%) and culture asepsis (69.44%). Highest culture establishment (80.55%) and minimum days to bud sprouting (7.62 days) was recorded with Benzyl adenine + Kinetin (3.0 + 1.0 mgL^?1) but maximum length (4.33 cm) and leaf number (7.78) of established micro shoots was recorded with Benzyl adenine + Kinetin (1.0 + 0.5 mgL^?1). Maximum proliferated shoots (2.41) and an optimum proliferation percentage (77.78 %) was recorded with Benzyl adenine + Kinetin (3.0 + 0.5 mgL^?1). Minimum size of proliferated shoots (2.02 cm) was recorded with Benzyl adenine + Kinetin (3.0 + 1.0 mgL^?1) followed by 2.25 cm recorded with Benzyl adenine + Kinetin (3.0 + 0.5 mgL^?1). Highest rooting (63.93%), primary root number/microshoot (4.74) and longest primary roots (34.67 mm) were recorded with IBA (2.0 mgL^?1). IBA yielded better results than NAA in terms of higher rooting percentage and root number. However, days to root initiation were found minimum (22.00) with 2.0 mgL^?1 of NAA. Highest ex vitro survival of rooted microshoots (89.67%) was recorded with IBA (2.0 mgL^?1).     

Improved soil physicochemical,biological properties and net income following the application of inorganic NPK fertilizer and biochar for maize production

A field experiment was conducted in 2019 (minor season) and 2020 (major season) to study soil properties and net income response to inorganic NPK fertilizer and biochar application for maize production. The experiment was made up of 2 × 3 factorial combinations of biochar (0 kg ha^?1, 2000 kg ha^?1) and inorganic NPK fertilizer (0:0:0 kg NPK ha^?1, recommended rate; 90:60:60 kg N: P:K ha^?1, half of recommended rate; 45:30:30 kg N:P:K ha^?1). In both seasons, biochar and inorganic NPK fertilizer applied separately or in combination improved soil properties (dehydrogenase activity, CEC, organic carbon, bacterial and fungal population, microbial biomass carbon and basal respiration rates) and yield significantly. In 2019, however, mineral N and available P did not increase in biochar amended plots. Significant interaction effect was observed between biochar and NPK fertilizer application which could be related to positive soil conditioning of biochar and biochar surface charges which enhanced retention and steady release of nutrient supplied by NPK fertilizer for maize use. Maize grain yield and profit in both crop seasons increased significantly and followed an increasing order of control < sole biochar < NPK (half rate) < NPK (full rate) < combined biochar + NPK (full rate) = combined biochar + NPK (half rate). Farmers in this agro ecological zone are encouraged to apply biochar + inorganic NPK fertilizer (45:30:30) due to its low total production cost, improved maize grain yield and high net income compared to the full rate (90:60:60) or full rate + biochar.     

Household energy and recycling of nutrients and carbon to the soil in integrated crop‐livestock farming systems: a case study in Kumbursa village,Central Highlands of Ethiopia

Soil amendment with organic wastes in the Highlands of Ethiopia has been greatly reduced by widespread use of dung cakes and crop residues as fuels. This study assessed the interaction between household energy and recycling of nutrients and carbon to the soil using household survey, focus group discussions, key informant interviews, direct observations and measurements between 2014 and 2015 in Kumbursa village (Central Highlands of Ethiopia). All surveyed households were entirely dependent on biomass fuel for cooking, with production and consumption rates directly related to wealth status, which significantly varied (P < 0.001) among three farm wealth groups (poor, medium and rich). Crop residues and dung cakes accounted for 80(±3)% by energy content and 85(±4)% by dry mass weight of total biomass fuel consumption. Mean losses were 59(±2) kg ha^?1 yr^?1 nitrogen (109(±8) kg yr^?1 per household), 13.9(±0.3) kg ha^?1 yr^?1 phosphorus (26(±2) kg yr^?1 per household), 79(±2) kg ha^?1 yr^?1 potassium (150(±11) kg yr^?1 per household) and 2100(±40) kg ha^?1 yr^?1 organic carbon (3000(±300) kg yr^?1 per household). Rich farmers lost significantly more carbon and nutrients in fuel than farmers in other wealth groups. However, these losses were spread over a larger area, so losses per land area were significantly higher for medium and poor than for rich farmers. This means that the land of poorer farmers is likely to become degraded more rapidly due to fuel limitations than that of rich farmers, so increasing the poverty gap. The estimated financial loss per household due to not using dung and crop residues as organic fertilizer was 162(±8) USSoil amendment with organic wastes in the Highlands of Ethiopia has been greatly reduced by widespread use of dung cakes and crop residues as fuels. This study assessed the interaction between household energy and recycling of nutrients and carbon to the soil using household survey, focus group discussions, key informant interviews, direct observations and measurements between 2014 and 2015 in Kumbursa village (Central Highlands of Ethiopia). All surveyed households were entirely dependent on biomass fuel for cooking, with production and consumption rates directly related to wealth status, which significantly varied (P < 0.001) among three farm wealth groups (poor, medium and rich). Crop residues and dung cakes accounted for 80(±3)% by energy content and 85(±4)% by dry mass weight of total biomass fuel consumption. Mean losses were 59(±2) kg ha^?1 yr^?1 nitrogen (109(±8) kg yr^?1 per household), 13.9(±0.3) kg ha^?1 yr^?1 phosphorus (26(±2) kg yr^?1 per household), 79(±2) kg ha^?1 yr^?1 potassium (150(±11) kg yr^?1 per household) and 2100(±40) kg ha^?1 yr^?1 organic carbon (3000(±300) kg yr^?1 per household). Rich farmers lost significantly more carbon and nutrients in fuel than farmers in other wealth groups. However, these losses were spread over a larger area, so losses per land area were significantly higher for medium and poor than for rich farmers. This means that the land of poorer farmers is likely to become degraded more rapidly due to fuel limitations than that of rich farmers, so increasing the poverty gap. The estimated financial loss per household due to not using dung and crop residues as organic fertilizer was 162(±8) US$ yr^?1. However, this is less than their value as fuels, which was 490(±20) US$ yr^?1. Therefore, farmers will only be persuaded to use these valuable assets as soil improvers if an alternative, cheaper fuel source can be found.