Comparative evaluation of PCR using IS6110 and a new target in the detection of tuberculous lymphadenitis

We evaluated TRC4 primers using polymerase chain reaction (PCR) which amplify a new target sequence from Mycobacterium tuberculosis genome to diagnose tuberculous lymphadenitis and compared the results with PCR using the widely used IS6110 primers. The PCR results were also compared with conventional methods like smear, culture and histopathology. The sensitivity of PCR using both probes is higher than the conventional methods. Out of 101 samples analysed (49 fresh and 52 fixed specimens), PCR using IS6110 and TRC4 primers was positive in 64 and 70 samples, respectively, whereas results with culture and histopathology methods were positive only in 49 and 58 samples, respectively. The problem of false negativity of IS6110 due to the absence of IS6110 copy in 4 M. tuberculosis isolates was overcome by using TRC4 primers. The results indicate that with improvement in PCR techniques, PCR using both probes, IS6110 and TRC4 can be a rapid and sensitive adjunct to conventional techniques in the diagnosis of tuberculous lymphadenitis

Pulse crops as effective living mulches: An eco-conscious weed management approach

The evolution of weed management strategies from basic cultural techniques to novel, integrated approaches reflects technological advancements that promise further improvements in weed management strategies, fostering more efficient and eco-friendly farming practices. Using legume crops as living mulches for weed suppression has gained considerable attention in agricultural systems. This method involves strategically planting leguminous cover crops as intercrops to inhibit weed growth and improve soil health, potentially boosting crop yields through reduced weed pressure and enhanced nutrient availability. The successful implementation of living mulches requires careful selection of crop species, optimal planting density, and appropriate management practices. Choosing compatible legumes, optimizing planting geometry and employing suitable termination methods are essential for maximizing the weed-suppressing and soil-enhancing benefits of living mulches. The efficacy of intercropping systems in controlling weeds largely depends on intercrop components' growth rate and duration. Weed management strategies rely on understanding plant interactions, including the competitive ability of main crops at various growth stages to inhibit weed expansion. While intercropping shows promise for enhancing crop dominance over weeds, weed control efficiency varies among different intercrops due to factors affecting the intercrop-weed relationship. Smallholder farmers find this practice appealing for improving labour productivity and land use through intensification and resource utilization for maximum yield. Research on developing genotypes suitable for weed suppression and studies on combined herbicide applications and optimal dosage determination for effective control of mixed weed flora is necessary. The shift towards integrating pulse crops as a cornerstone in weed management strategies presents a promising avenue for research and application. The comparative analysis underscored in this review showcases the capacity of legumes to offer a viable alternative to synthetic herbicides and mechanical controls, paving the way for their increased adoption in diverse farming systems

Biocontrol activity of yeast and AM fungi against Fusarium oxysporum f. sp. Lycopersici

Fusarium oxysporum f. sp. lycopersici, the causal agent of Fusarium wilt in tomato, posed a significant threat to tomato cultivation. This study investigated the biocontrol potential of yeast isolates and Arbuscular Mycorrhizal Fungi (AMF) against this pathogen. Soil and phyllosphere samples were collected from tomato fields in Tamil Nadu, India, leading to the isolation of 120 yeast strains using serial dilution and leaf imprinting techniques. Morphological characterization grouped the isolates with 35 unique colonies were selected for further analysis. Molecular characterization identified three key yeast isolates: Rhodosporidium toruloides (Y2), Moesziomyces antarcticus (Y14) and Pichia kudriavzevii (Y16). Under pot culture conditions, the combined application of AMF and yeast isolates significantly reduced Fusarium wilt incidence. Treatment T5 (AMF liquid-based inoculum + soil yeast Y14) exhibited the highest root colonization (86.66 %), maximum spore load (10397 spores) and minimal disease incidence (11 %), with an 89 % disease reduction compared to the control. This treatment also enhanced tomato plant growth metrics, including height (121.00 cm), root length (61.10 cm) and antioxidant enzyme activity (peroxidase: 0.392 min/g, polyphenol oxidase: 0.791 min/g). Yield parameters were also improved, with maximum fruit weight (19.45 g) and fruit count (6.24) observed in T5-treated plants

Diversity and ecological guild analysis of the oil palm fungal microbiome across root, rhizosphere, and soil compartments

The rhizosphere microbiome is a major determinant of plant health, which can interact with the host directly and indirectly to promote or suppress productivity. Oil palm is one of the world’s most important crops, constituting over a third of global vegetable oil production. Currently there is little understanding of the oil palm microbiome and its contribution to plant health and productivity, with existing knowledge based almost entirely on culture dependent studies. We investigated the diversity and composition of the oil palm fungal microbiome in the bulk soil, rhizosphere soil, and roots of 2-, 18-, and 35-year old plantations in Selangor, Malaysia. The fungal community showed substantial variation between the plantations, accounting for 19.7% of community composition, with compartment (root, rhizosphere soil, and bulk soil), and soil properties (pH, C, N, and P) contributing 6.5 and 7.2% of community variation, respectively. Rhizosphere soil and roots supported distinct communities compared to the bulk soil, with significant enrichment of Agaricomycetes, Glomeromycetes, and Lecanoromycetes in roots. Several putative plant pathogens were abundant in roots in all the plantations, including taxa related to Prospodicola mexicana and Pleurostoma sp. The mycorrhizal status and dependency of oil palm has yet to be established, and using 18S rRNA primers we found considerable between-site variation in Glomeromycotinian community composition, accounting for 31.2% of variation. There was evidence for the selection of Glomeromycotinian communities in oil palm roots in the older plantations but compartment had a weak effect on community composition, accounting for 3.9% of variation, while soil variables accounted for 9% of community variation. While diverse Mucoromycotinian fungi were detected, they showed very low abundance and diversity within roots compared to bulk soil, and were not closely related to taxa which have been linked to fine root endophyte mycorrhizal morphology. Many of the fungal sequences showed low similarity to established genera, indicating the presence of substantial novel diversity with significance for plant health within the oil palm microbiome