Annual Research & Review in Biology

Evaluation of Tephrosia purpurea and Eucalyptus spp. Leaf Extracts for Eco-Friendly Weed Management in Maize and Brinjal

2026-07-09T07:04:27+00:00

Weed infestation is a major constraint to crop productivity, particularly in organic and low-input systems where reliance on synthetic herbicides is restricted. This study evaluated the weed-suppressive potential of botanical extracts in maize and brinjal under field conditions. The experiment was conducted during 2024–2025 at Kumaraguru Institute of Agriculture using a Randomised Block Design. Treatments included combinations of kolunji extract, Eucalyptus extract, cow urine and neem oil, along with an untreated control and a weed-free treatment maintained by hand weeding. Weed population, weed dry weight, weed control efficiency, weed index, leaf area index and economic returns were assessed. Among the botanical treatments, T4, comprising kolunji extract 10% + Eucalyptus extract 10% + neem oil 10%, consistently recorded better weed suppression than the other botanical combinations. In maize, T4 recorded the lowest weed population and dry weed weight among botanical treatments at both 30 and 50 DAS, with weed control efficiency of 20.00% and 38.33%, respectively. In brinjal, T4 also showed comparatively better suppression, with 20.69% weed control efficiency at 40 DAS. The weed-free treatment recorded the highest LAI and yield, but T4 produced the highest benefit–cost ratio (1.18). The findings indicate that the kolunji + Eucalyptus + neem oil combination may serve as an eco-friendly component of integrated weed management, although it should be supplemented with other weed-control practices.

Probiotic Potential and Quorum Quenching Activity of Lactic Acid Bacteria Isolated from Indigenous Fermented Foods

2026-07-13T09:02:58+00:00

Objectives: The present study isolate lactic acid bacteria (LAB) from diverse traditional Indian fermented foods and evaluate their functional probiotic potential by assessing probiotic attributes, safety profiles and quorum-quenching (QQ) activity.

Materials and Methods: Fifteen LAB strains were isolated from indigenous Indian fermented foods. The isolates were evaluated for gastrointestinal tolerance through simulated stress tests involving mild (pH 4.0) to extreme (pH 2.0) acidic conditions and 0.5% bile salts. Functional assays assessed colonisation potential through cell surface hydrophobicity and auto-aggregation. Safety was evaluated using haemolysis assays and susceptibility testing against clinically relevant antibiotics targeting cell-wall and protein synthesis. Crude secondary metabolite extracts were screened for QQ activity using a Chromobacterium violaceum biosensor by measuring inhibition of violacein production.

Results: All 15 isolates survived simulated gastrointestinal stress under pH 4.0 and 0.5% bile salt conditions. Strain JUFB showed the highest overall survival, including under extreme acid stress (pH 2.0), and exhibited the greatest cell surface hydrophobicity and auto-aggregation, indicating stronger colonisation-associated potential. Safety assessment confirmed that all isolates were non-haemolytic (γ-haemolysis) and susceptible to the tested antibiotics. Crude extracts from JUFF, JUBM and JUFB showed quorum-quenching activity by inhibiting violacein production in the C. violaceum biosensor without evident bactericidal effects.

Conclusion: The evaluated LAB isolates, particularly JUFB, demonstrated favourable in vitro probiotic viability and preliminary safety attributes. Their quorum-quenching activity suggests potential for disrupting bacterial communication and supports further investigation of selected isolates and metabolites for anti-virulence and anti-biofilm applications.

PGPR and PGPF Mediated Seed Bio-priming for Improving Seed Germination and Early Seedling Growth in Acer oblongum (Himalayan Maple)

2026-07-17T08:28:57+00:00

Background: Acer oblongum (Himalayan maple) is an ecologically and socio-economically important Himalayan tree species. Poor natural regeneration and inconsistent seed germination in its natural habitats constrain its propagation, conservation, and nursery-scale multiplication.

Aim: The present study aimed to evaluate the effects of plant growth-promoting rhizobacteria (PGPR) and plant growth-promoting fungi (PGPF), used as seed bio-priming agents, on germination percentage and early seedling vigour of A. oblongum under in vitro conditions.

Study Design: The study was conducted using a completely randomised design (CRD) to evaluate the effects of microbial treatments on germination percentage, mean germination time, germination value, peak value, germination index, root length, shoot length, and total seedling length. In vitro analyses were performed using the selected PGPR and PGPF isolates. The experiment comprised seven treatments: an untreated control, P. gessardii, P. mosselii, P. fluorescens, B. subtilis, a bacterial consortium, and Trichoderma spp. Bio-primed seeds were incubated in a germinator, and germination was monitored daily throughout the experimental period.

Results: Microbial treatments significantly affected germination parameters and early seedling performance. The highest germination percentage was observed in seeds treated with Trichoderma (38.40%), followed by Pseudomonas mosselii (34.40%), compared with the control (28.00%). Root length, shoot length, collar diameter, and seed vigour index were highest in seeds treated with Trichoderma, followed by the consortium, compared with the control.

Conclusion: Among the tested treatments, Trichoderma spp. was the most effective and produced the highest germination percentage, germination value, peak value, germination index, root length, shoot length, total seedling length, and seed vigour index in Acer oblongum.

Economic Impact of Replacing Concentrate Mixture with Moringa oleifera and Chaya (Cnidoscolus aconitifolius) Based Pellets in the Diet of Lactating Barbari Goats

2026-07-17T13:06:40+00:00

Aims: The study aims to evaluate the economic impact of replacing part of the concentrate mixture with Moringa oleifera and Chaya (Cnidoscolus aconitifolius) leaf-based pellets, alone and in combination, on feed cost, net return, and the benefit-cost ratio in lactating Barbari goats using partial budget analysis.

Study Design: A four-group comparative feeding trial comprising one control group and three pellet-supplemented treatment groups in which part of the concentrate mixture was replaced with pellets.

Place and Duration of Study: Livestock Research Centre, ICAR-National Dairy Research Institute (NDRI), Karnal, Haryana, India, from May to August.

Methodology: Twenty-four healthy, adult, lactating Barbari goats, balanced for dry matter intake (DMI), body weight, and parity, were divided into four groups of six animals each. The control group (T₀) received a standard diet of roughage and concentrate (60:40), whereas the three treatment groups received the same basal diet, with part of the concentrate replaced by Moringa-based (T₁), Chaya-based (T₂), or combined Moringa-Chaya (T₃) pellets at an inclusion level of 8%. DMI and milk yield were recorded over a 90-day lactation period, and partial budget analysis was used to calculate feed cost, income from milk sales, and the benefit-cost ratio for each group.

Results: Milk yield was numerically higher in all pellet-fed groups than in the control, although the differences were not statistically significant. All three treatment groups had lower feed costs and higher net returns than the control. The combined Moringa-Chaya group (T₃) had the lowest feed cost (INR 26.47/kg goat/day), the highest milk yield (0.59 kg/day), the highest net return (INR 10.11/goat/day), and the best benefit-cost ratio (1.39), compared with INR 28.60/kg goat/day, 0.53 kg/day, INR 4.26/goat/day, and 1.15, respectively, for the control (T₀).

Conclusion: Replacing part of the concentrate mixture with Moringa oleifera and Chaya leaf-based pellets, particularly in combination, may be a cost-effective strategy for improving the profitability of small-scale goat farming while enabling productive use of locally available, environmentally sustainable feed resources. Confirmation through larger, longer-term studies with complete nutrient-composition and statistical data is recommended before widespread adoption.

Influence of Salinity on Heavy Metal Toxicity: Insights from Euryhaline Fishes

2026-07-07T10:33:41+00:00

Heavy metal pollution in aquatic environments remains a persistent concern because metals accumulate in fish tissues and interfere with essential physiological functions. In euryhaline fishes, metal toxicity is closely linked to salinity, which influences metal uptake, speciation, bioavailability, ion competition, membrane permeability and the energetic cost of osmoregulation. Under low-salinity conditions, fish generally absorb higher metal loads through the gills, digestive tract and, in early life stages, the skin. In contrast, higher salinity often reduces the activity of free metal ions through chloride binding and competition with other ions. However, these effects vary according to metal type, fish species, life stage, exposure duration and water chemistry. The gills, liver and kidneys are the main organs involved in metal uptake, detoxification, ion regulation and excretion, making them particularly vulnerable to toxic injury. At the cellular level, heavy metals can induce oxidative stress, lipid and DNA damage, mitochondrial dysfunction, altered gene expression and cell death. Salinity may intensify or reduce these effects by changing metal absorption and the energetic demands of salt balance. Fish respond through antioxidant enzymes, metallothioneins, ion transporters, heat-shock proteins and mitochondrial regulation. This review synthesises current evidence on salinity-modulated heavy metal toxicity in euryhaline fishes at physiological, cellular and molecular levels, identifies key knowledge gaps and outlines future research needs for ecological risk assessment, environmental monitoring and fish health.

Insecticide Resistance Evolution in Global Agricultural Pests: Molecular Mechanisms and Management in a Changing Climate

2026-07-13T08:54:00+00:00

Insecticides remain the primary tool for suppressing arthropod pests that threaten global food production, yet sustained and intensive use across diverse production systems has contributed to the repeated evolution of resistance in taxonomically diverse pest species. Using a narrative review approach, this article integrates molecular, ecological, and climate-related evidence to examine insecticide resistance as an evolutionary process shaped jointly by chemical selection, pest biology, and changing environmental conditions. This review synthesises current understanding of the molecular basis of insecticide resistance, encompassing target-site insensitivity, enhanced metabolic detoxification, reduced cuticular penetration, and altered behaviour, with particular attention to the genes and mutations that underlie resistance to pyrethroids, organophosphates, carbamates, neonicotinoids, diamides, and microbial toxins derived from Bacillus thuringiensis. The review then considers how anthropogenic climate change is reshaping the ecological and evolutionary context in which resistance arises, through range expansion, altered voltinism, changes in overwintering survival, and shifts in selection intensity associated with modified pesticide use patterns. Case studies drawn from the fall armyworm, diamondback moth, cotton bollworm, tomato leafminer, aphids, whiteflies, and mosquito disease vectors illustrate how these mechanisms interact with agronomic and climatic pressures in the field. This integrative framing distinguishes the review from mechanism-centred accounts by linking specific resistance pathways to field-level management decisions under shifting climatic and agronomic contexts. The review closes with an appraisal of resistance management strategies, including mode-of-action rotation, biotechnological interventions such as RNA interference and gene editing, and the integration of resistance monitoring into adaptive pest management frameworks. Persistent gaps remain in the translation of molecular diagnostics into field-deployable resistance management, and in anticipating how a warming climate will alter the tempo and geography of resistance evolution. Addressing these gaps will require closer integration between molecular entomology, agroecology, and climate science.