Increased Plant Dry Weight Research Articles

Seed treatments and seedling root soaking in biological agents improved plant growth and reduced bacterial leaf blight disease incidence in rice

Bacterial leaf blight (BLB) is caused by Xanthomonas oryzae pv. oryzae (Xoo), a seed-soil-air-borne pathogen that can reduce 60% of rice yield. The primary study intended to investigate the effect of seed treatments and root soaking with biological agents (a mixture of Pseudomonas diminuta and Bacillus subtilis) on plant growth and the severity of BLB in a greenhouse. A split-plot experimental design was used with seed treatments as the main plot: negative control, positive control (Xoo inoculated), bactericide (streptomycin sulfate 20%) 0.2%, biopriming with biological agents 108 CFU ml−1, matriconditioning plus bactericide 0.2%, biomatriconditioning with biological agents 108 CFU ml−1. The subplots were root soaking: untreated, bactericide 0.1%, 0.2%, 0.4%, 0.6%; biological agents 106 CFU ml−1, 108 CFU ml−1, and 1010 CFU ml−1. Biomatriconditioning reduced the BLB incidence three weeks after sowing from 10.6% to 1.7% and increased plant height four weeks after transplanting (WAT). Biomatriconditioning followed by root soaking in the biological agents or 0.4 % bactericide increased plant dry weight 3 WAT. Biomatriconditioning or root soaking in the biological agents (106 CFU ml−1) provided the most significant number of tillers 4 WAT.

EFEKTIVITAS BERBAGAI AGENS HAYATI DALAM MENINGKATKAN PERTUMBUHAN TANAMAN TOMAT (Lycopersicum esculentum Mill.)

The research aims to determine the effectiveness of various biological agents in increasing the growth of tomato plants. The study used a randomized block design, consisting of 10 treatments, namely without the use of biological agents, Pseudomonas sp. SWRIIA02, Bacillus sp. CKD061, Pseudomonas sp. Ab06, Pseudomonas sp. Bb05, SWRIIA02 + CKD061, Ab06 + CKD061, Bb05 + CKD061, SWRIIA02 + CKD061 and SWRII02 + CKD061 + Bb05 and each treatment was repeated 3 times. The results showed that the treatment of biological agents had a very significant effect on plant height 14 DAP, number of leaves 12 DAP, plant dry weight and significantly affected plant height 28 DAP, 42 DAP, stem diameter 42 DAP, root fresh weight, root dry weight and length root. The biological agent Pseudomonas sp. SWRIIA02, Bb05+CKD061, Bacillus sp. CKD061, SWRIIA02+CKD061+Bb05 were better at increasing the growth of local tomato plants compared to those without biological agents, with the percentage increase in plant dry weight in each of these treatments reaching 62.30%, 58.78%, 55.91% and 51.76% which was not significantly different from other treatments but significantly different from the treatment without biological agents.

Exogenously Applied Sulphur Improves Growth, Photosynthetic Efficiency, Enzymatic Activities, Mineral Nutrient Contents, Yield and Quality of Brassica juncea L.

Background: Due to increasing domestic and industrial demand, edible oil production is not keeping up with demand. To fill this gap, the productivity of oilseeds can be increased by applying adequate nutrients, particularly sulphur (S), at the crucial growth stage. Purpose: The present study aims to explore the best concentration of S for its foliar application on various cultivars of mustard. Methods: A factorial randomized pot experiment was conducted to investigate the role of leaf-applied S on growth, physiobiochemistry, yield and quality traits of three cultivars of Brassica juncea L. (mustard). Five levels of S viz. 0 (water), 15, 30, 45 and 60 ppm S constituted one variant, and the three cultivars (Chutki, Nath Sona and Rohini) were the other variants. The various levels of S were sprayed at 50 and 70 days after sowing (DAS). The growth and physio-biochemical characteristics were studied at 90 DAS, and yield and quality attributes at 120 DAS (harvest). Results: The data indicated that increasing S levels up to 45 ppm S improved all parameters of mustard and thereafter (at the level above 45 ppm S) decreased. Cultivar Nath Sona, followed by Rohini and Chutki, performed best. Among the foliar spray treatment of different levels of S, the application of 45 ppm S increased plant dry weight by 40.21, 35.65 and 30.96%, photosynthetic rate by 28.27, 27.44 and 36.29%, pods of a plant by 15.23, 12.12 and 10.80%, seed yield of a plant by 7.54, 3.89 and 4.91%, oil content by 48.70, 46.31 and 43.15% and oil yield of a plant by 24.56, 23.93 and 22.35% in cultivar Nath Sona, Rohini and Chutki, respectively, compared with their respective water-treated plants. Moreover, the oil was examined by GC-MS technique for its various components. The analysis revealed that there were 36 compounds in the oil of the non-treated plants and 44 compounds in the oil of plants treated with 45 ppm S. The extra compounds resulted from the application of 45 ppm S. Conclusion: It may be concluded that two sprays of 45 ppm S proved effective in improving the growth, physio-biochemical characteristics, yield and quality of cultivars of mustard, particularly Nath Sona.

Dual RNA and 16S ribosomal DNA sequencing reveal arbuscular mycorrhizal fungi-mediated mitigation of selenate stress in Zea mays L. and reshaping of soil microbiota

Excessively high concentrations of selenium (Se) in soil are toxic to crop plants, and inoculation with arbuscular mycorrhizal fungi (AMF) can reverse Se stress in maize (Zea mays L.). To investigate the underlying mechanisms, maize seedlings were treated with sodium selenate (5 mg Se[VI] kg-1) and/or AMF (Funneliformis mosseae and Claroideoglomus etunicatum). Dual RNA sequencing in mycorrhiza and 16 S ribosomal DNA sequencing in soil were performed. The results showed that Se(VI) application alone decreased plant dry weight, but increased plant Se concentration, total Se content (mainly selenocysteine), and root superoxide content. Inoculation with either F. mosseae or C. etunicatum increased plant dry weight, decreased Se accumulation and selenocysteine proportion, enhanced root peroxidase activity, and alleviated oxidative stress in Se(VI)-treated plants. Inoculation also downregulated the expression of genes encoding Se transporters, assimilation enzymes, and cysteine-rich receptor-like kinases in Se(VI)-stressed plants, similar to plant–pathogen interaction and glutathione metabolism related genes. Conversely, genes encoding selenium-binding proteins and those related to phenylpropanoid biosynthesis were upregulated in inoculated plants under Se(VI) stress. Compared with Se(VI)-free plants, Se tolerance index, symbiotic feedback percentage on plant dry weight, and root colonization rate were all increased in inoculated plants under Se(VI) stress, corresponding to upregulated expression of ‘key genes’ in symbiosis. AMF inoculation increased bacterial diversity, decreased the relative abundances of selenobacteria related to plant Se absorption (e.g., Proteobacteria and Firmicutes), and improved bacterial network complexity in Se(VI)-stressed soils. We suggest that stress-mediated enhancement of mycorrhizal symbiosis contributed to plant Se(VI) tolerance, whereas AMF-mediated reshaping of soil bacterial community structure prevented excessive Se accumulation in maize.

Effect of Nitrogen and Spacing on Vegetative Growth and Pod Characters of Okra Abelmoschus esculantus (L.) Moench Cv Al Hindi

Nitrogen is the most important nutrient to the plant, and its dose depends on the amount, availability to the plant and the plant density. This study was conducted in 20 September 2021 to the end of the year, to investigate the effect of nitrogen fertilizer and plant spacing on Okra Abelmoschus esculanntus (L.) Moennch vegetative growth and pod characters. The treatments were laid out as factorial arrangement in a Split Randomized Blocked Design, and replicated four times. Four nitrogen doses: N₀; 0, N₁; 119, N₂; 238 and N₃; 357 Kg ha^-1 and three plant spacing: S₁; 30, S₂; 40 and S₃; 50 cm plant apart, were examined. The analyses of variance reflected that the growth parameters significantly increased with increased plant spacing, while pod attributes were not affected except pod dry weight, which is weighty in middle plant spacing. Increasing nitrogen fertilizer increased plant fresh and dry weight, while decreasing nitrogen increased plant and pod dry weight and pod dry matter, moreover the middle dose of nitrogen gave the heavies pod fresh weight, while pod length and girth were not affected. The combination between higher dose of nitrogen and plant spacing donates the heaviest plant fresh and dry weight, while the higher plant dry matter is presented by the lower dose of nitrogen with higher plant spacing, which also increased plant dry weight. Overall plant spacing, the minimum fertilizer dose maximized plant dry matter, while this dose with both narrowest plant spacing gave the heaviest pod dry weight and widest pod girth, pod girth is also the biggest with the narrowest plant spacing having no fertilizer. Lowering plant spacing received nitrogen in a middle amount increased pod length. It could be concluded that optimum green pod quality of pod fresh weight may be considered with interaction effects of higher density with middle dose of nitrogen. The lower and middle densities with minimum dose of nitrogen may be considered optimal for the heaviest pod dry weight and widest pod girth. Regardless of plant density, the lower dose of nitrogen is optimal for the pod dry matter.

Synergetic effect of complex soil amendments to improve soil quality and alleviate toxicity of heavy metal(loid)s in contaminated arable soil: toward securing crop food safety and productivity.

Globally, various types of soil amendments have been used to improve the fertility and quality of soils in agricultural lands. In heavy metal(loid) (HM)-contaminated land, the soil amendments can also act as an immobilizing agent, thereby detoxifying HMs. A pot experiment was conducted to investigate the effects of three different complex amendments, including T1 (gypsum + peat moss + steel slag; GPMSS), T2 (GPMSS + lime), and T3 (GPMSS + lime + sulfate), on biogeochemical properties of the HM-contaminated arable soils, including Soil A and Soil B, and the magnitude of HM uptake by Chinese cabbage (Brassica rapa L.) for 6weeks. All the examined complex amendments improved soils' physical and biological properties by increasing the water-stable aggregate (WSA) ratio by 18-54% and dehydrogenase activity (DHA) by 300-1333mg triphenyl formazan (TPF) kg-1 24h-1 in comparison to control soils. The concentrations of HMs accumulated in B. rapa appeared to decrease tremendously, attributed to effectively immobilizing the HMs in soils by incorporating complex amendments mediated by soil pH, dissolved organic carbon (DOC), and complexation with the components of amendments. All these positive changes in soil properties resulted in the elevation of B. rapa productivity. For instance, T1 treatment induced an increase of plant dry weight (DW) by 3.7-3.9 times compared to the controls. Suppose there are no typical differences in the efficiency among the treatments. In that case, our findings still suggest that using complex amendments for the HM-contaminated arable soils would be beneficial by bringing a synergetic effect on improving soil biogeochemical properties and alleviating HM toxicity, which eventually can enhance plant growth performance.

Amelioration of Salinity Stressed Soil Using Natural Zeolite for Improving Soil Properties and Chinese Cabbage Agronomic Performances

Salinity stress is the major abiotic stress for crop production. The purpose of this study was to evaluate the effectiveness of zeolite on improving soil properties, the growth, and yield of Chinese cabbage. This pot experiment was conducted from September to November 2020 at the Research and Teaching Field of the Faculty of Agriculture, consisted of 6 treatment levels, i.e. (1) control, (2) soil + 6.9 g NaCl /10 kg soil, (3) soil + 6.9 g Na2SO4 /10 kg soil, (4) soil + 3.2 g zeolite /10 kg soil, (5) soil + 6.9 g NaCl /10 kg soil + 3.2 g zeolite /10 kg soil, and (6) soil + 6.9 g Na2SO4 /10 kg soil + 3.2 g zeolite /10 kg of soil, and arranged in a completely randomized design with 3 replications. The application of zeolite decreased the EC of salinized soil and increased the soil CEC. NaCl salinity stress reduced plant height (23%), number of leaves (22%), fresh weight of roots (165%), dry weight of roots (170%), stalk length (32%), and plant dry weight (131%), while Na2SO4 salinity stress only reduced the number of leaves (23%). The addition of zeolite to salinized NaCl soil increased stalk length (39%), plant fresh weight (172%), leaf fresh weight (174%), plant dry weight (133%), and leaf dry weight (23%), while to salinized Na2SO4 soil only increased plant dry weight (90%) and leaf dry weight (177%). The overall results show that the addition of zeolite can effectively ameliorate salinity stress due to NaCl.

Cerium Oxide Salicylic Acid Nanoparticles’ (CeO2: SA-NPs) Foliar Application and In-Soil Animal Manure Use Influence the Growth and Physiological Responses of Aloe vera L.

Aloe vera is an economic crop due to the presence of a gel-like substance inside the leaves, which contains polysaccharides, vitamins, proteins, fats, and amino acids. There is an ongoing need for this plant and its products for diverse food and pharmaceutical industries. To meet good agricultural practices, we studied the effect of manure application (0%, 10%, and 20% of v/v of soil) and foliar application with distilled water, salicylic acid (SA, 13.8 mg L−1 equivalent to 100 µM), cerium oxide nanoparticles (CeO2-NPs, 50 mg L−1), and cerium oxide salicylic acid nanoparticles (CeO2: SA-NPs; 100 µM + 50 mg L−1) on the growth and physiological responses of Aloe vera, and a factorial experiment was arranged based on a completely randomized design with three replications at Azarbaijan Shahid Madani University, Iran. The results showed that foliar application of CeO2: SA-NPs with the soil-based application of 10% and 20% manure increased plant dry weight and aloin content. The highest harvest index, economic yield, shoots-to-roots ratio, gel dry weight, chlorophyll a and b content, phenolics content of gel, and leaf and gel flavonoids’ content, as well as potassium, magnesium, zinc, and iron content, were obtained by the CeO2: SA-NPs × 20% manure treatment combination. The 10% and 20% manure and foliar application with CeO2-NPs, SA, and CeO2: SA-NPs increased the phenolics content of leaves compared to the control. Manure application (20%) positively affected the plant’s phosphorus content. The results revealed that co-application of soil-based cow manure and foliar CeO2: SA-NPs stimulated the growth and physiological responses of Aloe vera, and the results would be helpful to the agricultural extension sections and pioneer farmers.

EFFECT OF BIOGAS DIGESTATE ON GROWTH AND SOME POTENTIAL TOXIC ELEMENT CONCENTRATIONS OF WHEAT

In this study it was aimed to investigate the effect of biogas digested (BD) on the growth and some potential toxic element (B, Cd, Cr, Ni, Co and Pb) concentrations of wheat grown under greenhouse conditions. For this reason, 0, 15 and 30 tha<sup<-1</sup< of BD were applied to the soils and left incubations during 0, 30 and 60 days. After incubation period is ended wheat seeds were sawn and left for growth during 2 months. Results indicated that BD dosages and incubation periods increased plant dry weight. Applications of BD did not affect B, Cd and Co concentrations of wheat and Cr and Ni concentrations decreased generally with the BD dosages. Similarly, incubation showed decreasing effect on Pb concentration of wheat. Plant Co, Cr and Pb uptakes did not vary with the applications, other element uptakes increased in the parallels of plant dry weights. Looking at the element concentrations of wheat it was seen that all element concentrations were in the ranges of acceptable levels. So, it was concluded that the application of BD did not pose a risk for potential toxic elements on the growth of the wheat.

Soil property determines the ability of rhizobial inoculation to enhance nitrogen fixation and phosphorus acquisition in soybean

Soil property impacts the efficacy of rhizobial inoculation and rhizosphere processes. However, very few comparative studies have been done to analyze the effects of rhizobial inoculants on plant nitrogen (N) and phosphorus (P) in different soils. The aim of the present study was, therefore, to evaluate N fixation and P acquisition of inoculated soybean (Glycine max) plants in acid and calcareous soils in the field as well as in a pot culture. Our results demonstrate that soil pH determined the effectiveness of rhizobial inoculation. Rhizobial inoculation resulted in greater effects on nodule traits and plant N content in calcareous soil than in acid soil compared with those in non-inoculated plants. A low P availability significantly decreased nodule number and dry weight in both soils relative to P-application treatments. Rhizobial inoculation did not affect root morphological traits and arbuscular mycorrhizal colonization, but strongly increased the amount of carboxylates in the rhizosheath and plant P content. It also increased plant dry weight and yield in calcareous soil. In conclusion, the beneficial effects of rhizobial inoculation on N and P content and soybean growth were particularly pronounced in calcareous soil. The mining strategy of P acquisition was responsible for increases in P content in inoculated soybean plants compared with non-inoculated controls.

Testing Virulence of Different Species of Insect Associated Fungi against Yellow Mealworm (Coleoptera: Tenebrionidae) and Their Potential Growth Stimulation to Maize.

This paper investigates 71 isolates of two genera of entomopathogens, Metarhizium and Beauveria, and a biostimulative genus Trichoderma, for their ability to infect yellow mealworms (Tenebrio molitor) and to stimulate maize (Zea mays) growth. Fungal origin, host, and isolation methods were taken into account in virulence analysis as well. Isolates Metarhizium brunneum (1154) and Beauveria bassiana (2121) showed the highest mortality (100%) against T. molitor. High virulence seems to be associated with fungi isolated from wild adult mycosed insects, meadow habitats, and Lepidopteran hosts, but due to uneven sample distribution, we cannot draw firm conclusions. Trichoderma atroviride (2882) and Trichoderma gamsii (2883) increased shoot length, three Metarhizium robertsii isolates (2691, 2693, and 2688) increased root length and two M. robertsii isolates (2146 and 2794) increased plant dry weight. Considering both criteria, the isolate M. robertsii (2693) was the best as it caused the death of 73% T. molitor larvae and also significantly increased maize root length by 24.4%. The results warrant further studies with this isolate in a tri-trophic system.

Tomato phytochromes B1 and B2 are part of the responses to the nutritional stress induced by NPK deficiency.

Phytochromes are red-light photoreceptors that play an important role in regulating many responses of plants, including its nutritional control. Nutrient deficiency in plants has become a constraint for agricultural production; thus, we investigated the role of phytochromes B1 and B2 in the nutritional, physiological, and growth changes of the control genotype (WT) and both phyB1 and phyB2 tomato mutants (deficient in phyB1 and phyB2) under nutritional sufficiency and individual deficiency of N, P, and K. Under complete solution, the plants of phyB1 and phyB2 had a decreased N, P, and K accumulation compared with WT and consequently a reduced content of chlorophyll and carotenoids, and dry weight production. In the condition of N deficiency, phyB1 had decreased N absorption, pigments concentration, and plant dry weight, while increased oxidative stress of membranes (MDA content). Similarly, phyB2 also had reduced N absorption. The deficiency of phyB1 mitigated the effects of P deficiency as phyB1 mutant had improved nutritional and physiological responses, increasing plant dry weight production. In contrast, phyB2 reduced N accumulation, quantum efficiency of photosystem II (Fv/Fm), and the concentration of pigments, while it increased MDA. Under K deficiency, phyB1 displayed a reduced P accumulation, as well as the total concentration of chlorophylls and carotenoids and K use efficiency. An increased concentration of MDA was found in phyB2 plants, as well as a reduction in chlorophylls concentration and in the use efficiency of K. Together, these results indicate a new perspective on the control of phytochromes in the nutrition of tomato plants under nutritional stress.

Moderate Mn accumulation enhances growth and alters leaf hormone contents in the hyperaccumulator Celosia argentea Linn.

To better understand the unique concentration–response relationship in hyperaccumulators, the effects of manganese (Mn) accumulation on the growth of Celosia argentea Linn., a Mn hyperaccumulator, were investigated using hydroponic experiments. Manganese accumulation (8860–14200 mg/kg in leaves) is toxic to most plants but beneficial to the growth of C. argentea. The C. argentea root length and root surface area at Mn supply concentrations of 20 and 40 mg/L were significantly higher than those at 0.5 mg/L (control treatment). Leaf number and leaf area were 24 % and 66 % greater, respectively, at 20 mg Mn/L than at the control concentration. Moderate Mn accumulation (8860–14200 mg/kg) significantly increased plant dry weight (p < 0.05). However, high Mn accumulation (26,500 mg/kg) decreased plant dry weight. The chlorophyll content expressed a similar trend. The physiological responses of C. argentea to Mn may be regulated by endogenous hormones. Moderate Mn accumulation increased auxin, zeatin, gibberellin, and 6-benzylaminopurine contents, and decreased the abscisic acid content in the leaves (p < 0.05), thereby enhancing plant growth. However, high Mn accumulation significantly increased leaf jasmonic acid and abscisic acid contents (p < 0.05), which inhibited plant growth and stimulated stress tolerance. These findings suggested that the alterations in hormone homeostasis induced by Mn accumulation promoted growth and Mn tolerance in C. argentea.

EFFECT OF BIOGAS DIGESTATE ON GROWTH AND SOME POTENTIAL TOXIC ELEMENT CONCENTRATIONS OF WHEAT

In this study it was aimed to investigate the effect of biogas digested (BD) on the growth and some potential toxic element (B, Cd, Cr, Ni, Co and Pb) concentrations of wheat grown under greenhouse conditions. For this reason, 0, 15 and 30 tha-1 of BD were applied to the soils and left incubations during 0, 30 and 60 days. After incubation period is ended wheat seeds were sawn and left for growth during 2 months. Results indicated that BD dosages and incubation periods increased plant dry weight. Applications of BD did not affect B, Cd and Co concentrations of wheat and Cr and Ni concentrations decreased generally with the BD dosages. Similarly, incubation showed decreasing effect on Pb concentration of wheat. Plant Co, Cr and Pb uptakes did not vary with the applications, other element uptakes increased in the parallels of plant dry weights. Looking at the element concentrations of wheat it was seen that all element concentrations were in the ranges of acceptable levels. So, it was concluded that the application of BD did not pose a risk for potential toxic elements on the growth of the wheat.

Mann+Hummel, Germany

To better understand the unique concentration–response relationship in hyperaccumulators, the effects of manganese (Mn) accumulation on the growth of Celosia argentea Linn., a Mn hyperaccumulator, were investigated using hydroponic experiments. Manganese accumulation (8860–14200 mg/kg in leaves) is toxic to most plants but beneficial to the growth of C. argentea. The C. argentea root length and root surface area at Mn supply concentrations of 20 and 40 mg/L were significantly higher than those at 0.5 mg/L (control treatment). Leaf number and leaf area were 24 % and 66 % greater, respectively, at 20 mg Mn/L than at the control concentration. Moderate Mn accumulation (8860–14200 mg/kg) significantly increased plant dry weight (p < 0.05). However, high Mn accumulation (26,500 mg/kg) decreased plant dry weight. The chlorophyll content expressed a similar trend. The physiological responses of C. argentea to Mn may be regulated by endogenous hormones. Moderate Mn accumulation increased auxin, zeatin, gibberellin, and 6-benzylaminopurine contents, and decreased the abscisic acid content in the leaves (p < 0.05), thereby enhancing plant growth. However, high Mn accumulation significantly increased leaf jasmonic acid and abscisic acid contents (p < 0.05), which inhibited plant growth and stimulated stress tolerance. These findings suggested that the alterations in hormone homeostasis induced by Mn accumulation promoted growth and Mn tolerance in C. argentea.

The relative contribution of indigenous and introduced arbuscular mycorrhizal fungi and rhizobia to plant nutrient acquisition in soybean/maize intercropping in unsterilized soils

It has been demonstrated that intercropped crops may benefit from inoculation with rhizobia or arbuscular mycorrhizal (AM) fungi in soybean/maize intercropping systems under sterilized conditions. Little is known about the relative contribution of indigenous and introduced AM fungi and rhizobia to nutrient acquisition of intercropped soybean and maize in unsterilized soils. In this study, we evaluated the effectiveness of indigenous and introduced AM fungi and rhizobia in a soybean/maize intercropping system under unsterilized soil conditions. The results show that introduced rhizobial inoculation promoted soybean nodulation and growth. Single AM fungal inoculation promoted indigenous rhizobial nodulation and increased maize AM root colonization, but had little effect on maize growth. Co-inoculation strongly increased plant dry weight, and nitrogen (N) and phosphorus (P) content of the intercropped soybean compared to those with only indigenous rhizobial and AM fungal communities, but had no effect on those of maize in the same intercropped system. These results indicate that AM fungal inoculation promoted nodulation by indigenous rhizobia. Effective rhizobial inoculation combined with introduced AM fungi may not only promote symbiotic N2 fixation, but also enhance rhizosphere processes, which has the potential to improve nutrient acquisition in the field. Soybean is a weak competitor compared with maize in intercropping systems. Inoculation with introduced AM and rhizobia ameliorated the growth suppression of intercropped soybean, but inhibited growth of intercropped maize, indicating that inoculation of introduced AM fungi and/or rhizobia partly shifted the competitive advantage from maize to soybean. In conclusion, introduced AM fungi and rhizobia contributed more than indigenous populations to promoting growth and nutrient acquisition of the intercropped soybean in unsterilized soils.

Response Of Soybean Growth In Sandy Coastal Soil To Seaweed Compost And Biochar Application

The coastal area is sub-optimal land which is poor in nutrients. Therefore it is necessary to add organic matter to increase nutrients content. The research that has been conducted aims to determine the effect of seaweed compost and biochar application on soybean growth on sandy coastal soils. The research was arranged in a Completely Randomized Design consisting of two factors. The first factor was the dose of seaweed compost, namely 0, 20, 40, 60. The second factor was giving biochar, namely without biochar and giving biochar. The research data were analyzed using Analysis of Variance, if there was a significant difference, it was tested with the Duncans Multiple Range test at the 5% level. The results showed that the interaction between seaweed compost and biochar significantly increased the growth rate of plant height. Biochar significantly increased plant dry weight and pod number. Seaweed compost only significantly increased root dry weight. The number of nodules, root length, and harvest index were not affected by seaweed compost and biochar.

Adding Far-Red to Red-Blue Light-Emitting Diode Light Promotes Yield of Lettuce at Different Planting Densities.

The economic viability and energy use of vertical farms strongly depend on the efficiency of the use of light. Increasing far-red radiation (FR, 700–800 nm) relative to photosynthetically active radiation (PAR, 400–700 nm) may induce shade avoidance responses including stem elongation and leaf expansion, which would benefit light interception, and FR might even be photosynthetically active when used in combination with PAR. The aims of this study are to investigate the interaction between FR and planting density and to quantify the underlying components of the FR effects on growth. Lettuce (Lactuca sativa cv. Expertise RZ) was grown in a climate chamber under two FR treatments (0 or 52 μmol m–2 s–1) and three planting densities (23, 37, and 51 plants m–2). PAR of 89% red and 11% blue was kept at 218 μmol m–2 s–1. Adding FR increased plant dry weight after 4 weeks by 46–77% (largest effect at lowest planting density) and leaf area by 58–75% (largest effect at middle planting density). Radiation use efficiency (RUE: plant dry weight per unit of incident radiation, 400–800 nm) increased by 17–42% and incident light use efficiency (LUEinc: plant dry weight per unit of incident PAR, 400–700 nm) increased by 46–77% by adding FR; the largest FR effects were observed at the lowest planting density. Intercepted light use efficiency (LUEint: plant dry weight per unit of intercepted PAR) increased by adding FR (8–23%). Neither specific leaf area nor net leaf photosynthetic rate was influenced by FR. We conclude that supplemental FR increased plant biomass production mainly by faster leaf area expansion, which increased light interception. The effects of FR on plant dry weight are stronger at low than at high planting density. Additionally, an increased LUEint may contribute to the increased biomass production.

A, The ESTIMATION OF ECONOMIC THRESHOLDS OF JUNGLE RICE (ECHINOCHLOA COLONA L.) AND FALSE AMARANTH (DIGERA ARVENSIS FORSSK.) IN DIRECT SEEDED RICE

ABSTRACT There is little understanding about ecological interference of weeds in direct-seeded rice. To get estimates of economic thresholds of two weeds in direct seeded rice, two-year field trials were conducted at research area of College of Agriculture, University of Sargodha, Punjab-Pakistan. Treatments included 0, 22, 44, 66 and 88 plants m-2 densities of each of Echinochloa colona and Digera arvensis laid out in randomized complete block design. Augmented densities of E. colona (0, 22, 44, 66 and 88 weed plants m-2) enhanced its plant dry biomass up to 348 and 353%; and relative competitive index maximally to 80 and 77% in years 2015 and 2016, respectively. While the corresponding increases in plant dry weight and relative competitive index of D. arvensis were 367 and 360% and 79 and 82%. The enhancement in N (up to 258 &amp; 257 %), P (up to 220 &amp; 232%) and K (up to 293 &amp; 301%) uptake in years 2015 and 2016, respectively were made by E. Colona whereas the corresponding increases in N, P and K assimilation by D. arvensis were as far as 265 &amp; 257%, 238 &amp; 233% and 305 &amp; 298%, respectively. The declines in growth and yield of rice were observed in response to growing number of both the weeds. Rice grain yield losses ranged between 9.8 to 80% and 28 to 80% by E. Colona and D. arvensis. The economic thresholds of false amaranth and jungle rice were estimated to be 1.6-1.4 plants m-2 and 2.2-2.6 plants m-2, respectively.

Interaction of ZnO nanoparticle and AM fungi mitigates Pb toxicity in wheat by upregulating antioxidants and restricted uptake of Pb

The study aims at investigating the efficacy of individual as well as combined application of AM fungi (Glomus macrocarpum) and ZnO nanoparticles on the uptake of lead and its toxicity in wheat (Triticum aestivum L.). The plants were grown in pots with different treatments of AM Fungi, ZnO NP, and Pb. The individual applications of AM fungi (Glomus macrocarpum) and ZnO NPs increased the growth and biochemical attributes of wheat and decreased the Pb uptake under Pb stress. The combined application of AM fungi (Glomus macrocarpum) and ZnO nanoparticles synergistically enhanced the overall growth performance of the plant and significantly reduced the uptake of Pb in wheat grown in Pb spiked soils. The combined application was effective, with 30.66 % increase in plant height, 30.62 % increase in plant fresh weight, 54.26 % increase in plant dry weight, 45.45 % increase in total chlorophyll content, 19.59 % increase in proline content, 26.65 % higher activity of SOD, 15.12 % higher activity of catalase (CAT), 17.69 % increase in H2O2 content, 17.69 % increase in lipid peroxidation content, 52.09 % and 58.19 % decrease in Pb concentration in root and shoot of wheat, respectively, grown in Pb spiked soil (100 mg kg−1 soil). The results indicate that combined application of AM fungi and ZnO nanoparticles can be a promising technique for the utilization of Pb-contaminated soils.