The study highlights the importance of integrating organic resources, such as vermicompost and biofertilizers with inorganic fertilizers to sustain coconut yields and manage costs. The experimental trial was conducted from 2016 to 2020 in a 47-year-old East Coast Tall coconut garden at Coconut Research Station in South India. The research evaluated four nutrient management treatments viz., T₁ (75% Recommended Dose of Fertilizer (RDF) + 25% N organic), T₂ (50% RDF + 50% N organic), T₃ (100% N organic) and a control (100% RDF). Intercrops included black pepper (Piper nigrum), banana (Musa acuminata) and cocoa (Theobroma cacao). Organic manure significantly improved soil physical properties, water retention and overall soil health. The T₂ treatment achieved the highest yields for coconut, cocoa, banana and black pepper. The added soil health parameters supported to these findings, with T₂ showing the highest fungal (15.27 × 10³ cfu/g of soil) and bacterial populations (17.25 × 10⁵ cfu/g of soil), along with a significant earthworm population (26/m²), indicating enhanced soil ecosystem health. Additionally, soil moisture content was highest under T₃ (100% organic) across various depths, followed by T₂, highlighting the critical role of organic matter in improving soil moisture conservation. The economic feasibility analysis, including a net present value (NPV), benefit/cost ratio (B/C ratio) and an internal rate of return (IRR), revealed T₂ to be the most economically viable nutrient management strategy. This study highlights the economic benefits of intercropping coconuts using an integrated nutrient management (INM) approach, demonstrating its superiority over traditional monocropping practices.

Rice is a vital staple food crop widely cultivated across diverse Asian agroclimatic zones. However, in recent years, the emergence of sheath rot disease, caused by Sarocladium oryzae, has severely impacted rice yields, devastating approximately half of rice production. Traditional methods of controlling plant diseases often have harmful effects on the environment and have led to the development of pathogenic resistance to various agrochemicals. In contrast, endophytes have shown great promise in managing plant diseases while enhancing plant growth and yield. The seed-associated endophyte Bacillus lichiniformis has demonstrated remarkable efficacy, exhibiting a 76.47% inhibition rate against S. oryzae. Beyond its antibiotic properties, this endophyte also promotes biostimulant activities, including the production of indole-3-acetic acid (IAA), siderophores, and the utilization of ammonia (NH3). Additionally, the analysis of secondary metabolites using gas chromatography-mass spectrometry (GC-MS) revealed a diverse array of compounds, including 9,12-Octadecadienoic acid (Z, Z)-TMS derivatives, Elaidic acid-TMS, Bis(2-ethylhexyl) phthalate, Caproic acid-TMS, Diethyl phthalate, Ricinoleic acid-2TMS derivatives, Mandelic acid-2TMS, and others. These compounds exhibit significant antifungal, antiviral, larvicidal, and antibacterial activities against various plant pathogens, highlighting the potential of Bacillus lichiniformis as a sustainable and effective biocontrol agent in rice cultivation. This research underscores the critical role of endophytes in promoting sustainable agricultural practices, offering an environmentally friendly alternative to chemical control methods while effectively combating emerging plant diseases.

Coconut is an important plantation crop in India. Many diseases severely impact coconut trees in the current climate change scenario, declining the vigor and yield of palms and deteriorating the quality of nuts on the trees. Basal stem rot caused by Ganoderma spp. is one of the most destructive diseases of coconut. Ganoderma can endure an extended period in the soil as a soil-borne pathogen. Chlamydospores are formed under unfavourable conditions, helping the pathogen's survival and spread of the disease. Rain and irrigation water also contribute to the spread from one field to another. This study assessed coconut consortia's efficiency in combating the basal stem rot disease at the field level. The experimental trial was conducted at Tittuvillai village of Thovalai panchayat, Kanyakumari district, from 2021–2022 to 2023–2024 for three consecutive years with four treatments and seven replications. The palms exhibiting the typical symptom were selected, and the experiment was started in 2021. A total of 28 palms displaying basal stem rot symptoms were randomly selected for the experiment. Four treatments were imposed, and the details of treatments include T1: Drenching of Coconut consortia (TNAU Cococon) @ 2 liters/palm along with application of mycorrhizae @ 100 g/palm at quarterly interval, T2: Drenching of Coconut consortia (TNAU Cococon) @ 2 litres/palm and root feeding with hexaconazole (0.2%) at quarterly interval, T3: Drenching of Bordeaux mixture 1% and T4: Control (Untreated). Among the four treatments, soil drenching of coconut consortia (TNAU Cococon) @ 2 liters/palm followed by root feeding with hexaconazole (0.2%) at quarterly intervals effectively reduced the disease index from 21.74 to 15.96 and enhanced nut yield from 67.14 to 90.00 nuts per palm per year in three years under field conditions.

Banana crop is affected by the pseudostem weevil (Odoiporus longicollis), which damages the pseudostem and causes the plant to collapse. This weevil causes yield losses of between 10% and 90%. The study was conducted on the evaluation of various management modules for pseudo stem weevil in banana (var. Red Banana) in farmer's fields with four treatments and seven replications in an RBD design. Treatments were imposed on 5^th, 6^th and 7th month after planting which includes spraying of cassava leaf based biopesticides (Nanma) in the pseudostem, filling the leaf axil with Heterorhabditis (EPN), spraying of Chlorpyriphos 20EC in the pseudo stem. Percentage of plants affected and extent of pseudostem borer infestation, individual bunch weight were measured. In plants treated with the biopesticide based on cassava leaves (Nanma), crop damage was found to be 2.0%; in contrast, EPN showed 13.0% damage, Chlorophyriphos showed 15.2% damage, and untreated control plants showed 35.5% damage. The Weevil infestation was 2.4 % in cassava leaf based biopesticides (Nanma) treatment followed by 8.60% in EPN treatment and 14.60 per cent in Chlorophyriphos treatment and 36.60 per cent in untreated control. The average increase in bunch weight was 26.16 percent for plants treated with the cassava leaf-based biopesticides (Nanma), 21.52 percent for EPN, and 18.60 percent for Chlorophyriphos when compared to untreated control plants. The study revealed that the spraying of cassava leaf based biopesticides reduced the incidence of pseudostem weevil with higher yield.

Field experiments were conducted for three years to manage soil and foliar diseases of sesame by integrated approaches using bioagents and fungicides. The experiment was conducted in different seasons for the management of Macrophomina root rot, stem blight and Alternaria capsule blight. Seed treatment with biocontrol agent Pseudomonas fluorescens (Pf1) followed by foliar spray with Difenconazole @ 0.05% on 30 and 45 DAS reduced the root rot from 19.03 to 5.73%, stem blight from 48.67% to 20.68% and capsule blight from 41.33% to 16.41% and increased yield from 376 to 640.05 kg/ha with a B:C ratio of 2.13 in sesame. Thus, seed treatment with Pseudomonas fluorescens (Pf1) followed by foliar spray with Difenconazole @ 0.05% on 30 and 45 DAS provided maximum protection from foliar and soil borne diseases in sesame with higher seed yield and B:C ratio, so that this may be recommended for the management of diseases in sesame.

Stem rot of peanut, caused by the fungus S. rolfsii, is a significant disease occurring worldwide and leads to considerable yield losses. Due to the adverse effects of chemical fungicides, biological control methods have gained importance in recent years. The efficacy of biocontrol can be enhanced by applying indigenous strains that effectively suppress and compete with in situ pathogenic microorganisms. In this study, native PGPR isolates from the genera Bacillus and Pseudomonas were isolated and tested for their antagonistic activity against S. rolfsii, growth-promoting ability and yield enhancement in peanuts under both in vitro and in vivo conditions. The potential PGPR isolates were subjected for partial sequencing of the 16S rRNA gene and identified as B. subtilis PB(20d), B. amyloliquefaciens PB(40d), B. subtilis PB(50d), Paenibacillus campinasensis PB(60d) and Pseudomonas aeruginosa PP(30d). The phylogenetic tree organized these strains into their clades alongside reference strains from the NCBI database. Results from pot culture and field experiments revealed that the treatment with the combination of identified PGPR strains exhibited a lower incidence of stem rot and a higher yield of peanuts compared to individual applications and control treatment. Therefore, the combined application of native PGPR strains has proven to be more effective in addressing the variability in the performance of individual biocontrol agents and improving overall efficacy.