Plant Growth Parameters Research Articles

Management of Root Knot Nematode Meloidogyne incognita on Carrot

A pot experiment was conducted in the net house, Department of Nematology, during the rabi season to know the efficacy of certain botanicals, Azadiracta indica, Azeratum conizoides, Tagetes erecta, Ricinus Communis, Lantana camara and Parthenium hysterophorus each @ 1.0 and 1.5%(w/w) against Meloidogyne incognita on carrot. The result revealed that all the treatments were effective in increasing plant growth parameters with corresponding decreased in number of galls, eggmasses per root system and final nematode population in soil over control. The treatment with Azadiracta indica @1.5%(w/w) was most effective in increasing plant growth characters, reducing number of galls, eggmasses per root system and final nematode population in soil. A microplot experiment was conducted during rabi season to study the efficacy of Glomus fasciculatum, consortia (T. harzianum, T. viride and Pseudomonas fluorescenes) and vermicompost for the management of M.incognita on carrot. All the treatments were effective in increasing plant growth parameters and yield with corresponding decreased in number of galls, eggmasses per root system and final nematode population in soil over control. The treatment with G. fasciculatum @ 300 spores/m2 + consortia @ 5ml/lt + vermicompost @ 1.25t/ha was found most effective in increasing plant growth parameters, yield of carrot and reducing number of galls and egg masses and final nematode population in soil.

Zinc solubilization and organic acid production by the entomopathogenic fungus, Metarhizium pingshaense sheds light on its key ecological role in the environment

We report for the first-time higher zinc (Zn) solubilization efficiency and plant growth promotion by an entomopathogenic fungus (EPF), Metarhizium pingshaense IISR-EPF-14, which was earlier isolated from Conogethes punctiferalis, a pest of global importance. The Zn solubilizing efficiency of the fungus varied depending on the type of insoluble source of Zn used, which was observed to be 1.6 times higher in Zn3(PO4)2–amended media compared to ZnO media. In liquid media, there was a 6.2-fold increase in available Zn in ZnO–amended media, whereas a 20.2-fold increase in available Zn was recorded in Zn3(PO4)2 medium. We ascribe the production of various organic acids such as gluconic, keto-gluconic, oxalic, tartaric, malonic, succinic and formic acids, which in general, interact with insoluble Zn sources and make them soluble by forming metal cations and displacing anions as the major mechanism for Zn solubilization by M. pingshaense. However, the type and amount of organic acid produced in the media varied depending on the source of Zn used and the incubation period. Application of the fungus alone and in combination with insoluble Zn sources enhanced various plant growth parameters in rice and cardamom plants. Moreover, the uptake of Zn in rice plants was enhanced up to ~2.5-fold by fungal application. The fungus also exhibited various other plant growth-promoting traits, such as production of Indole-3-acetic acid, ammonia, siderophores, solubilization of mineral phosphate, and production of hydrolytic enzymes such as α-amylase, protease, and pectinase. Hence, apart from its use as a biological control agent, M. pingshaense has the potential to be used as a bio-fortifier to enhance the solubilization and uptake of Zn from nutrient poor soils under field conditions. Our findings shed light on the broader ecological role played by this fungus and widen its scope for utilization in sustainable agriculture.

Evaluation of phyllosphere bacterial biocontrol agents for the suppression of rice foliar diseases

AbstractPhyllosphere colonizing antagonistic bacterial isolates were evaluated for managing major rice foliar diseases, namely brown spot caused by Bipolaris oryzae and sheath rot caused by Sarocladium oryzae. Among these various isolates, Pseudomonas aeruginosa isolate 1 effectively inhibited the mycelial growth of B. oryzae and S. oryzae. The volatile compounds of Bacillus subtilis isolates effectively inhibited the mycelial growth of S. oryzae and B. oryzae. Non‐volatile compounds of P. aeruginosa isolate 2 and B. subtilis isolate 1 recorded the maximum inhibition of mycelial growth of B. oryzae and S. oryzae, respectively. P. aeruginosa isolates produced fluorescent pigments and hydrogen cyanide (HCN), whereas isolates of Bacillus spp. did not. All the isolates of P. aeruginosa and Bacillus spp. produced protease enzymes. P. aeruginosa isolates solubilized phosphate, whereas isolates of Bacillus spp. did not. Rice seeds treated with these bacterial suspensions showed improvement in plant growth parameters. The foliar application of two bacterial strains, namely P. aeruginosa isolate 1 + B. subtilis isolate 1 recorded the minimum brown spot and sheath rot disease incidence. Thus, the present showed that phyllosphere colonizing P. aeruginosa and B. subtilis have the potential application for managing foliar fungal diseases of rice plants.

Residual hydrocarbons in long-term contaminated soils: implications to risk-based management

Petroleum hydrocarbon (PHC) contamination is a widespread and severe environmental issue affecting many countries’ resource sectors. PHCs are mixtures of hydrocarbon compounds with varying molar masses that naturally attenuate at different rates. Lighter fractions attenuate first, followed by medium-molar-mass constituents, while larger molecules remain for longer periods. This results in significant regulatory challenges concerning residual hydrocarbons in long-term contaminated soils. This study examined the potential risks associated with residual PHC and its implications for risk-based management of heavily contaminated soils (23,000–26,000 mg PHC/kg). Ecotoxicological properties, such as seedling emergence and growth of two native plant species—small Flinders grass (Iseilema membranaceum) and ruby saltbush (Enchylaena tomentosa)—and earthworm survival tests in PHC-contaminated soils, were assessed. Additionally, the effects of aging on the attenuation of PHC in contaminated soils were evaluated. Toxicity responses of plant growth parameters were determined as no-observed-effect concentrations: 75%–100% for seedling emergence, < 25%–75% for plant shoot height, and 75%–100% for earthworm survival. After 42 weeks of aging, the total PHC levels in weathered soils decreased by 14% to 30% and by 67% in diesel-spiked soil due to natural attenuation. Dehydrogenase enzyme activity in soils increased during the initial aging period. Furthermore, a clear shift of bacterial communities was observed in the soils following aging, including enrichment of PHC-resistant and -utilizing bacteria—for example, Nocardia sp. This study underscores the potential of natural attenuation for eco-friendly and cost-effective soil management, underlining that its success depends on site-specific factors like water content and nutrient availability. Therefore, we recommend detailed soil assessments to evaluate these conditions prior to adopting a risk-based management approach.

Plant Physiological Performances, Plant Growth, Grain Yield and Methane Emission of Rice (Oryza Sativa L.) in Response to Water Management as Adaptation Strategy for Climate Change

Continuously flooded rice systems are a major contributor to the greenhouse gases (GHG) emissions in the agriculture sector in Malaysia. Intermittent irrigation has been recommended to replace conventional rice water management to save water and reduce GHG emissions without compromising rice yields. This study was conducted in two growing seasons at Malaysia’s largest rice granary area to determine the effectiveness of different water management practices on conserving water, mitigating GHG and maintaining rice grain yields. Three water management treatments were continuous flooding (CF), saturated and wet conditions from transplanting to heading and flooding until maturity (S-F) and continuous saturated and wet conditions (CS). The results showed that S-F and CS reduced water inputs between 15.0-16.8% and 32.0-34.0% as compared to CF, respectively. Water-saving treatments mostly did not significantly affect the plant's physiological performance, plant growth parameters, growth rate, grain yield and yield parameters. The results indicated that soil saturated and wet conditions provided adequate soil moisture content for the plant’s requirement similar to flooding conditions. Maintaining soil at saturated and wet conditions during the vegetative stage reduced 24.18-39.76% of methane emissions. However, maintaining soil at saturated and wet conditions throughout the growing season reduced 34.52-55.08% of methane emissions. In conclusion, intermittent irrigation could be an effective adaptation technique for simultaneously saving water and mitigating GHG while maintaining high rice grain yields in rice cultivation systems.

Effect of micronutrients, rhizobium, salicylic acid, and effective microorganisms in plant growth and yield characteristics of green gram [Vigna radiata (L.) Wilczek] in Rupandehi, Nepal

Nepal has a very diverse topography and ecosystem, with mountains in the north and lush plains in the south. Despite the diverse ecology, the production of green gram is still in its minority. This experiment was conducted to assess the effect of micronutrients (Zn, B, Mo, Co, and Mn), rhizobium, effective micro-organisms, and salicylic acid in plant growth, yield, and yield attributes of green gram [Vigna radiata (L.) Wilczek] in Rupandehi district of Nepal in March 2021. Pratikshya variety of green gram was used as a test crop. Different levels of ZnSO4 and Borax, Ammonium Molybdate, Cobalt Nitrate, MnSO4, effective microorganism, Mixture, Salicylic acid, and Rhizobia along with control constituted treatments. Various application methods were used for applying treatments including soil incorporation, seed priming, inoculation, and foliar application. The results revealed that leaf area index, number of branches, number of pods per plant, and yield were significantly different (P < 0.05). Among various treatments, the mixture was found most effective in the case of grain yield (1048.1 kg ha−1), stover yield (2472.7 kg ha−1), biological yield (3520.8 kg ha−1), harvest index (31.2%), and the number of primary branches (4.9). Likewise, the number of secondary branches (6.86) was better with Borax@10 kg ha−1. There was no significant difference in the plant height, number of pods per plant, pod length, pod weight, number of grains per pod, and test weight between different treatments. ZnSO4 @ 25 kg ha−1 was found to have an impact on the number of mature, immature, and total pods per plant. Overall, the study concluded that the mixture of all micronutrients performed better in terms of grain yield while zinc sulphate had great potential for plant growth parameters which could improve the farmers’ livelihood. It is recommended to conduct multi-location trials in a larger domain.

Image Sensing, A Unique Tool for Early Detection of Nitrogen Deficiency of Tomato Grown in Hot and Humid Greenhouses

Protected culture (PC) answers the major issues in conventional agriculture, and thus helps feed the rising world population. Meanwhile, soilless culture has become an integral part of the PC, for sake of catering to the plant nutrient requirements precisely. Therefore, innovative intellective diagnostic systems for diagnosing nutrient deficiency symptoms in protected culture is a timely need. Hence this experiment was conducted to test the effectiveness of “Image Sensing” as a diagnostic tool for nitrogen deficiency under semi-intensive greenhouse management in hot and humid weather. In this study N deficiency symptoms of tomato were detected by leaf color changes, identified through image sensing, and the deficiency was confirmed with respect to retardation of plant growth. Tomato plants were subjected to a series of N treatments by providing 200, 100, 50, 25, and 12.5 percent of the recommended N supply for soilless culture tomatoes. The results showed that morphology changes like stem thickness, leaf area, plant height, and leaf number were significantly reduced along with a reduction of N supply (p&lt;0.05) beginning from 5th week after transplanting (WAT). Leaf images were processed in “ImageJ”, software” to determine the green color intensity of leaves. Image analysis showed that there was a significant difference among treatments since the 3rd WAT. The leaf color chart was less effective for distinguishing leaf color at the early stages of N deficiency. The results revealed that diagnosis of N deficiency in tomato leaves could be effectively done by image sensing much earlier than the use of plant growth parameters or morphological changes. Hence, image sensing can be used as a more effective diagnostic tool for early detection of N deficiency of tomato cultivations in hot and humid greenhouses, that can be used to improve crop management, especially in large large-scale commercial practices.

Effect of Organic Treatments on Growth Parameters of Guava (Psidium guajava L.)

A field experiment was conducted during the year 2020-21, at Deen Dayal Upadhyay Centre of Excellence for Organic Farming, CCS Haryana Agricultural University, Hisar. Different combinations of organic and microbial sources of nutrients (Poultry Manure, Vermicompost, FYM, Jeevamrit, Azotobacter and PSB) replicated thrice in Randomized Block Design. The maximum plant height (172.67 cm), plant spread (241.71 cm), stem girth (167.33 mm) and leaf area (62.47 cm2) were recorded at last stage of growth with FYM + Poultry manure + Azotobacter + PSB application followed by plant height (170.24 cm), plant spread (237.32 cm), stem girth (165.46 mm) and leaf area (61.29 cm2) in FYM + Poultry manure + PSB and minimum under control. Therefore, on the basic of results FYM + Poultry manure + Azotobacter + PSB found best for plant growth parameters.

Rhizospheric Fungal spp. of Tomato (Solanum lycopersicum L.) and Their Effect on Tomato Plant Growth and on Alternaria solani, the Causative Agent of Early Blight of Tomato

Tomato (Solanum lycopersicum L.) is a widely consumed crop throughout the world including Sri Lanka. Use of agrochemicals for enhanced yields and managing diseases associated with tomato results in deleterious impacts on soil microflora, fauna and leads to human health problems. A possible alternative is the use of rhizospheric microorganisms, as they are reported to improve productivity and protect various crops. Hence this study aimed to isolate rhizospheric fungal assemblages of tomato plants and evaluate their ability to solubilize phosphate while, controlling Alternaria solani, the causative agent of Early Blight of tomatoes. Rhizospheric fungi were isolated from commercial tomato cultivations in two agro-ecological zones (WM3b and IM2b), using soil dilution plate technique. Composite samples of soil attached to the root systems of five healthy plants, uprooted from each field were prepared and 10 g of each sample was used for the isolations. Twenty-seven fungal genera were isolated and Trichoderma and Penicillium were the frequently isolated genera. Phosphate solubilization ability of each fungal species was evaluated using Pikovskaya's agar and liquid medium, and four isolates (Eupenicillium sp., Talaromyces purpureogenus, Paecilomyces sp., and Purpureocillium lilacinum) with the highest phosphate solubilizing abilities were evaluated on tomato plant growth under greenhouse condition. The inocula of each fungal sp. were prepared by adding fifteen, 6mm diameter mycelial discs from each 5-day-old culture into polypropylene bags containing 90 g of sterile rice husk medium and incubated for 02 weeks at room temperature. Each pot contained a 4.6 kg layer of non- sieved sterilized potting medium (Sand: topsoil: Compost at 2:1:1 ratio) and a 2.5 kg layer of sieved medium on top, which was mixed with 15 g of inoculum. Three-week old, healthy tomato seedlings (variety-Bathiya) were planted (with 3 replicates) and allowed to grow with regular watering. Control pots contained potting medium with uninoculated sterile rice husk. Growth parameters such as Root and shoot lengths, fresh and dry weights of roots, shoots, and leaves were evaluated at 02-week intervals for 02 months and the results were analysed using ANOVA with Tukey‘s pairwise comparison. Plants treated with T. purpureogenus and P. lilacinum showed significant increases (p≤0.05) in all growth parameters in every evaluation. Dual culture plate assay on the Potato Dextrose Agar was used to test the effect of rhizospheric fungal spp. on the radial colony growth of A. solani, and Eupenicillium sp. showed the highest percentage inhibition (85.09±5.68%). Microscopic observations of inhibition zones between two colonies showed the presence of coils, loops, knobs, and haustoria, formed by inhibitory rhizospheric fungal species. Assays for Chitinase and Glucanase enzyme production showed that Mortierella sp.-1, P. lilacinum, Trichoderma sp.-1, and Acremonium sp. were the highest chitinase producers, whereas P. lilacinum was the highest glucanase producer. These results indicate the ability of some rhizospheric fungal species of tomato to increase the growth of tomato plants significantly by phosphate solubilization and ability to inhibit the growth of foliar pathogen A. solani under in vitro conditions. &#x0D; Keywords: Rhizospheric fungi, Phosphate solubilization, Dual culture plate, Plant growth parameters

Management of Free-floating Aquatic Weeds by Making Compost and Testing its Efficacy against Root-knot Nematode on Tomato

Aquatic weeds are one of the prime pollution causing agents in fresh water bodies of Sri Lanka. In Sri Lanka, free-floating aquatic weeds such as Salvinia molesta, Eichhornia crassipes, Azolla spp and Pistia stratiotes are proliferating quickly and invading rapidly to new water bodies where threatening biodiversity by impeding light penetration and altering BOD and COD of the waterbody. This research was aimed to manage the aquatic weeds by composting and testing its efficacy on root-knot nematodes. Aquatic weeds were collected, mixed with fresh cow dung in 1:1 ratio and allowed for decomposition for 21 days. The recommended dose of prepared different compost was applied to tomato along with garden compost as control. The experiment was conducted in Complete Randomized Design (CRD) with four replicates. The data on nutritional qualities of the compost, plant growth parameters, and gall index were recorded. The data were subjected to ANOVA using SAS 9.1 and Tukey's HSD multiple comparison test was used to determine the best treatment combination at P&lt;0.05. Total Nitrogen (N) content of composts were ranging from 1.42% to 5.6%. The highest significant N value of 5.6% was recorded in the Azolla spp based compost whereas the lowest N value of 1.42% was recorded in control. The highest total Phosphorus (P) content of 3.47% was observed in P. stratiotes based plant sample, whereas the lowest P value of 1.32% was recorded in the E. crassipes based compost. The total Potassium (K) content of this plant sample ranging from 1.3% to 24.4%. The highest K value of 24.4% was recorded in P. stratiotes based compost. The lowest K content of 1.3% was observed in control. Significantly higher shoot height (37.57 cm, 36.53), root length (18.75 cm and 17.5 cm), lower gall index (3.5,1.0), lower goal length (1.5 mm and 1.2 mm) and lower goal diameter (0.95 mm and 0.8 mm) were recorded in the application of S. molesta and Azolla spp based compost, respectively (P&lt;0.05). Considering superiority of N, P and K level, and nematode suppressing efficacy, S. molesta and Azolla spp. based composts are superior than other composts. Therefore, findings conclude that the compost made from aquatic weeds are good source of plant nutrition, and can be substitute to chemical nematicieds to manage the nematodes in organic agriculture. Extensive field studies are needed for recommendation &#x0D; Keywords: Aquatic weeds, Azolla spp., Compost, Root-knot Nematode

Biochar Derived from Pond Apple (Annona glabra) as a Fertilizer to Enhance the Crop Yield: A Sustainable Approach

The intensive use of inorganic fertilizers causes many economic, ecological, and social issues around the world. In the search to discover an effective fertilizer, biochar has been in the spotlight in recent years. Hence, the present study was focused on utilizing biochar derived from pond apple (Annona glabra), which is an aquatic invasive plant as a fertilizer without harming the environment. A pot experiment was carried out to determine the effects of biochar on plant growth. Biochar was applied to soil and growth differences were identified by comparing it with the control. Banana pepper (Capsicum annum) was selected as the experimental plant. Plant growth parameters (seed germination percentage, growth rate, root length, and number of leaves) were measured to determine the effects of biochar on plant growth. In each pot, 5 seeds of C. annum were sowed and examined for 14 days to get the germinate percentages. The other plant growth parameters were recorded after 45 days. Biochar treated with soil showed a significant increase (p&lt;0.05) in average growth rate (14.46±6.67%), root lengths (4.94±0.27 cm), and number of leaves (5.83±0.76) in comparison to the control while seed germination percentages were kept as same value. An optimizing process was carried out by increasing the amount of biochar (5%, 7%, 10% by weight) to determine the ideal amount of biochar on plant growth. Considering the average growth rate, the best result (21.43±1.01%) was shown in pot treated with 7% biochar by weight. Henceforth, the utilization of biochar derived from A. glabra as a fertilizer is an effective approach to enhance crop yield while limiting the spread of these invasive aquatic plants in a sustainable and eco-friendly manner. As a result, the current study has suggested a green, sustainable strategy for the efficient use of aquatic invasive plants.&#x0D; &#x0D; Keywords: Biochar, Fertilizers, Plant growth, Aquatic invasive plant&#x0D;

Isolation of Phosphate Solubilizing Fungi from Soil and Their Application in Plant Growth Promotion

Phosphorus plays a significant role in numerous physiological and metabolic processes in plants. Soil phosphorus is immobilized due to the formation of insoluble complexes. The use of efficient phosphate-solubilizing microorganisms opens up a new prospect for better crop productivity and for greater yield performance without affecting the soil health. Phosphate-solubilizing fungi (PSF) enhance available phosphorus released from soil, which contributes to P requirement of plants. Hence, the present study was designed to evaluate the utilization of PSF as a biofertilizer. Pikovskaya's Agar medium was used to isolate fungal species from compost and open dumpsite soil. Isolated fungi were labelled as PSF-X, PSF-Y, and PSF-Z. A pot experiment was carried out to determine the effect of isolated fungal strains. The isolated fungal strain was introduced to the developed potting media which contained compost and soil at 1:1 ratio. Soya bean was selected as the experimental plant. Plant growth parameters (shoot length and root length) were measured to determine the effect of isolated fungal strains. Plant growth parameters were recorded after 21days. Fungi inoculated pots showed a significant increase in both shoot and root lengths in comparison to the control (n=9, p&lt;0.05). Potting media consisting of PSF-X showed the best result. The highest root length (4.7±0.1 cm) and shoot length (35.8±1.2 cm) were recorded in pots inoculated with PSF-&#x0D; &#x0D; Hence, isolated PSF-X, PSF-Y, and PSF-Z are recommended as suitable biofertilizer strains for potting medium.&#x0D; &#x0D; &#x0D; Keywords: Fertilizer, Fungi strain, Phosphorus, Plant growth

Arbuscular Mycorrhizal Fungi Inducing Tomato Plant Resistance and Its Role in Control of Bemisia tabaci Under Greenhouse Conditions.

Arbuscular mycorrhizal fungi (AMF) are one of the environment-friendly organisms that enhance plant performance. AMF affect the herbivorous insect community by indirectly modifying host plant nutrient uptake, growth, and defense, also known as priming. In the current study, under greenhouse conditions, the effects of inoculating tomato seedlings with four species of AMF, i.e., Funneliformis mosseae, Rhizophagus intraradices, Rhizophagus irregularis, and Glomus iranicus, were studied in relation to tomato plant growth parameters, plant defense enzymes, and total phenol content, and additionally, the life table of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) feeding on these plants was determined. The results demonstrated that the growth parameters of tomato plants, including plant height, stem diameter, number of leaves, root volume, leaf surface area, weight of the root, and aerial organs (containing the leaves and stem), were greater and larger in the AMF-inoculated plants compared to the non-inoculated plants. Furthermore, there were higher defense enzyme activities, including peroxidase, phenylalanine ammonia lyase and polyphenol oxidase, and also higher total phenol contents in the AMF-inoculated plants. The whitefly life table characteristics were decreased in the group feeding on the AMF-inoculated plants. All together, the AMF colonization made the tomato plants more resistant against B. tabaci by improving plant growth and increasing defense enzymes. The degree of priming observed here suggests the potential of AMF to have expansive applications, including their implementation in sustainable agriculture.

Wastewater irrigation and Trichoderma colonization in tomato plants: effects on plant traits, antioxidant activity, and performance of the insect pest Macrosiphum euphorbiae

The scarcity of freshwater for agriculture in many regions has led to the application of sewage and saline water for irrigation. Irrigation with non-conventional water sources could become a non-harmful process for plant cultivation, and the effects of their use on crops should be monitored in order to develop optimal management strategies. One possibility to overcome potential barriers is to use biostimulants such as Trichoderma spp. fungi. Tomato is a crop of great economic importance in the world. This study investigated the joint effects of Trichoderma afroharzianum T-22 on tomato plants irrigated with simulated unconventional waters. The experiment consisted of a control and three water treatments. In the control, the plants were watered with distilled water. The three water treatments were obtained by using an irrigation water added with nitrogen, a wastewater effluent, and a mixed groundwater-wastewater effluents. Potted tomato plants (variety Bobcat) were grown in a controlled growth chamber. Antioxidant activity, susceptibility to the aphids Macrosiphum euphorbiae, and tomato plant growth parameters were estimated. Trichoderma afroharzianum T-22 had a positive effect on plant growth and antioxidant defenses when plants were irrigated with distilled water. Instead, no significant morphological effects induced by T. afroharzianum T-22 on plants were observed when unconventional water was used for irrigation. However, inoculation with T. afroharzianum T-22 activated a stress response that made the colonized plants more susceptible to aphid development and increased their fecundity and longevity. Thanks to this study, it may be possible for the first time to open a new discussion on the practical possibility of using reclaimed wastewater for crop irrigation with the addition of a growth-promoting fungal symbiont.

Vermicompost from Kitchen Waste and Paper Waste by Eudrilus eugeniae, Nutrient Analysis and Efficiency on Alternanthera sessilis Plant Growth

In India, a significant amount of paper and kitchen waste is produced, much of which is either burned, left outside, or landfilled, creating a significant challenge for its safe disposal. The Eudrilus eugeniae (Kinberg) earthworms can be used to convert all kitchen and paper waste into extremely useful, nutrient-rich vermicompost. The vermicompost contributes significantly to the growth and yield of various field crops, vegetables, flower and fruit crops. The use of organic residuals lowers production costs while eliminating the requirement for waste disposal and incineration. The present research was carried out to find out the potential vermicompost using kitchen and paper waste to compost on the Eudrilus eugeniae earthworm as it effectively decomposes waste. Vermicompost has been analysed to physicochemical parameters like pH, and the level of macronutrient, and micronutrient content namely nitrogen, phosphorous, potassium, iron, copper, manganese and zinc analyses between the 30th and 60th day of control (raw soil), kitchen and paper waste vermicomposting. The vegetable plant Alternanthera sessilis, commonly known as sessile joy weed or Ponnanganni, has been used to test and investigate the effectiveness of vermicompost. The plant growth parameters, especially root length, shoot length, and number of leaves has been studying. Finally, a comparison was made with plants growing on the 30th &amp;60th days of kitchen waste vermicompost and the 30th &amp; 60th days of paper waste vermicomposting. In final results, the plant obtains maximum growth in kitchen waste vermicompost as a result of Alternanthera sessilis (sessile Joyweed) growth on the 30th and 60th days. The kitchen waste vermicompost contains a higher amount of NPK content than the control and paper waste vermicomposts. Consequently, the Alternanthera sessilis plants thrived on the kitchen wastes.

Optimization of Chemical Fertilizer through Integrated Nutrient Management (INM) Approach and its Effect on Growth and Yield of Mustard (Brassica juncea L.)

A field experiment to test the optimization of chemical fertilizer use through Integrated Nutrient Management (INM) approach and its effect on growth and yield of Mustard (Brassica juncea L.) was carried out at Rampur agricultural field of Doon (P.G) College of Agriculture Science and Technology, Selaqui, Dehradun, Uttarakhand during the rabi season 2021-2022. The experiment comprised of nine treatments of organic and inorganic nutrient combination, viz T1- Control (No Fertilizer), T2- Recommended Dose of Fertilizer (RDF) (80:60:40 kg/ha), T3- 100 % vermicompost (6.0 t/ha), T4- 75% Farm Yard Manure (FYM) (15.0 t/ha) + 25% RDF (20:15:10 kg/ha), T5- 50% RDF (40:30:20 kg/ha) + FYM (5.0 t/ha) + green manure (2.5 t/ha) + gypsum (10.0 kg/ha), T6-50% RDF (40:30:20 kg/ha) + vermicompost (3.0 t/ha)+ gypsum (5.0 kg/ha), T7- 75% RDF (60:45:30 kg/ha) + vermicompost (2.5 t/ha), T8- 75% RDF (60:45:30 kg/ha) + vermicompost (1.5 t/ha) + green manure (1.5 t/ha), T9- 75% RDF (60:45:30 kg/ha) + FYM (1.5 t/ha) + vermicompost (1.0 t/ha) + green manure (1 t/ha) + gypsum (10.0 kg/ha), laid out in randomized block design with three replication. The results of experiment revealed that there was increase in plant growth parameters in the treatment T9, followed by treatment T8 and T5, respectively. Moreover, the maximum seed yield (2240.39 kg/ha) was observed under T9 over control, where no fertilizer application was applied. The present investigation established the fact that integrated use both organic and inorganic fertilizer can be recommended to the farmers as one of the key strategies for enhancing crop response in terms of growth and yield of mustard.

Enhancing quinoa (Chenopodium quinoa) growth in saline environments through salt-tolerant rhizobacteria from halophyte biotope.

The use of plant growth-promoting rhizobacteria (PGPR) in agriculture is one of the most promising approaches to improve plants' growth under salt stress and to support sustainable agriculture under climate change. In this context, our goal was to grow and enhance quinoa growth using native rhizobacteria that can withstand salt stress. To achieve this objective, we isolated rhizobacteria from three saline localities in a semi-arid region in Tunisia, which are characterized by different halophyte species and tested their plant growth-promoting (PGP) activities. Then, we inoculated quinoa seedlings cultivated on 300 mM NaCl with the three most efficient rhizobacteria. A positive effect of the three-salt tolerant rhizobacteria on the growth of quinoa under salinity was observed. In fact, the results of principal component analysis indicated that the inoculation of quinoa by salt-tolerant PGPR under high salinity had a prominent beneficial effect on various growth and physiological parameters of stressed plant, such as the biomass production, the roots length, the secondary roots number, proline content and photosynthesis activities. Three rhizobacteria were utilized in this investigation, and the molecular identification revealed that strain 1 is related to the Bacillus inaquosorum species, strain 2 to Bacillus thuringiensis species and strain 3 to Bacillus proteolyticus species. We can conclude that the saline soil, especially the halophytic rhizosphere, is a potential source of salt-tolerant plant growth-promoting rhizobacteria (ST-PGPR), which stimulate the growth of quinoa and improve its tolerance to salinity.

Paenibacillus lentimorbus alleviates nutrient deficiency-induced stress in Zea mays by modulating root system architecture, auxin signaling, and metabolic pathways.

Paenibacillus lentimorbus reprograms auxin signaling and metabolic pathways for modulating root system architecture to mitigate nutrient deficiency in maize crops. The arable land across the world is having deficiency and disproportionate nutrients, limiting crop productivity. In this study, the potential of plant growth-promoting rhizobacteria (PGPR) viz., Pseudomonas putida, Paenibacillus lentimorbus, and their consortium was explored for growth promotion in maize (Zea mays) under nutrient-deficient conditions. PGPR inoculation improved the overall health of plants under nutrient-deficient conditions. The PGPR inoculation significantly improved the root system architecture and also induced changes in root cortical aerenchyma. Based on plant growth and physiological parameters inoculation with P. lentimorbus performed better as compared to P. putida, consortium, and uninoculated control. Furthermore, expression of auxin signaling (rum1, rul1, lrp1, rtcs, rtcl) and root hair development (rth)-related genes modulated the root development process to improve nutrient acquisition and tolerance to nutrient-deficient conditions in P. lentimorbus inoculated maize plants. Further, GC-MS analysis indicated the involvement of metabolites including carbohydrates and organic acids due to the interaction between maize roots and P. lentimorbus under nutrient-deficient conditions. These findings affirm that P. lentimorbus enhance overall plant growth by modulating the root system of maize to provide better tolerance to nutrient-deficient condition.

Bacillus subtilis, a bacterial inhabitant in calcareous soil and its ability to demineralize fixed Fe and Zn salt in its habitat

Calcareous soils are unproductive for agriculture. World over 30 percent of soils are calcareous soils limiting crop cultivation and productivity. In calcareous soils, most of the plant nutrients and micronutrients are not freely available to the crop plants as these often lie in fixed or bonded form. Therefore, these nutrients have to be released from their bonded form into freely available form in such soils to make them available for crop plant growth. The application of microbial species native to such calcareous soils and having the ability and capacity to release such bonded nutrients into freely available form is a need of the day to convert these unproductive soils into productive ones. In the present investigation, we studied the presence of microbial flora particularly the bacterial species in the calcareous soil in western Maharashtra, India, and their role in the release of the bonded Fe and Zn micronutrients into a freely available form, from such soil to make these available for the kidney-bean plant growth. Six bacterial isolates of distinct colony morphology were isolated from the calcareous soil as the calcareous soil- inhabiting bacterial species, on a specialized enriched media. Their ability as Fe and Zn salt-releasing/de-mineralizing bacterial species was assessed. The release of Fe and Zn from their fixed form by these bacterial species was 0.80 and 1.80 µg/g of calcareous soil respectively. The release of Fe and Zn in calcareous soil was found to play a role in the growth and yield-attributing parameters of kidney-bean plants in calcareous soil. These morphologically distinct bacterial cultures were identified as Bacillus subtilis and Bacillus sp by using the MALDI Bio Typer classification protocol. These calcareous soils inhabiting bacterial species can be applied as bio-inoculants to the calcareous soil regularly to make them crop productive as well as for the reclamation of such calcareous soils.

Effects of Funneliformis mosseae on Growth and Photosynthetic Characteristics of Camellia oleifera under Different Nitrogen Forms

Nitrogen fertilizer increases agricultural yields but increases economic costs and causes a series of environmental problems. Arbuscular mycorrhizal fungi (AMF) have the potential to be used as biological fertilizer. However, the influence of nitrogen form on plant growth responsiveness to AMF inoculation is poorly understood. In this study, we investigated the effects of Funneliformis mosseae on growth, root morphology and photosynthetic characteristics of Camellia oleifera under different nitrogen forms during three harvest periods and clarified the most suitable nitrogen form for C. oleifera–AMF symbiosis. The results showed that urea, ammonium and nitrate nitrogen promoted plant growth and photosynthetic capacity, among which urea treatment had the highest value in all three harvests. No significant difference in plant growth parameters was observed between ammonium and nitrate nitrogen treatments in the first two harvests, while the plant height was significantly lower under ammonium nitrogen treatment than nitrate nitrogen treatment in the third harvest. Inoculation with F. mosseae in the presence of indigenous AMF could promote AMF colonization and plant growth at all three harvest times. Inoculation with F. mosseae significantly increased gas exchange parameters, the maximum photochemical efficiency (Fv/Fm) and the actual photochemical efficiency (ΦPSII). Inoculation with AMF increased the photochemical quenching coefficient (qP) better under urea treatment and improved the non-photochemical quenching coefficient (qN) better under ammonium nitrogen treatment. Principal component analysis showed that urea is the most beneficial nitrogen fertilizer for C. oleifera–AMF symbiosis. The results of this study provide a theoretical basis for the combination use of AMF and nitrogen fertilizer in agroforestry.