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This study aimed to identify efficient Trichoderma isolate(s) for the management of Fusarium wilt in peas. Four different pea germplasms (Sarsabz, Pea-09, Meteor and Supreme) were evaluated for resistance against Fusarium oxysporum in pot assay. Resistant germplasm exhibits a varying range of disease severity (23%) and percent disease index (21%), whereas susceptible and highly susceptible germplasm exhibit maximum disease severity (44–79%) and percent disease index (47–82%). The susceptible germplasm Meteor was selected for in vivo experiment. Five different Trichoderma spp. (Trichoderma koningii, T. hamatum, T. longibrachiatum, T. viride, and T. harzianum) were screened for the production of hydrolytic extracellular enzymes under in vitro. In-vitro biocontrol potential of Trichoderma spp. was assayed by percentage inhibition of dry mass of Fusarium oxysporum pisi (FOP) with Trichoderma spp. metabolite filtrate concentrations. Maximum growth inhibition was observed by T. harzianum (50–89%). T. harzianum metabolites in filtrate conc. (40%, 50%, and 60%) exhibited maximum reduction in biomass and were thus used for in vivo management of the disease. The pot experiment for in-vivo management also confirmed the maximum inhibition of FOP by T. harzianum metabolites filtrate at 60% by reducing disease parameters and enhancing growth, yield, and physiochemical and stress markers. Trichoderma strains led to an increase in chlorophyll and carotenoids (34-26%), Total phenolic 55%, Total protein content 60%, Total Flavonoid content 36%, and the increasing order of enzyme activities were as follows: CAT > POX > PPO > PAL in all treatments. These strains demonstrate excellent bio-control of Fusarium wilt in pea via induction of defense-related enzymes. The present work will help use Trichoderma species in disease management programme as an effective biocontrol agent against plant pathogens.

Background: Babesia infections in sheep can cause a wide range of clinical and laboratory presentations. Changes in Blood parameters are a meaningful manifestation of physiological and pathological changes in an organism. Aim: Therefore, the present study was conducted to analyze and compare haematological and biochemical parameters between blood profiles of Lohi sheep naturally infected and un-infected with Babesia ovis, the main causative agent of ovine babesiosis. Methods: Initially, blood and serum samples from 67 Lohi sheep were collected, DNA was extracted and babesial infection was detected through PCR. Overall infection rate of B. ovis was 37% (25/67). Sixteen infected (experiment group) and sixteen uninfected (control group) sheep that were apparently healthy with no history of previous treatment for Babesiosis, were selected for haemato-biochemical analysis. Blood samples were analyzed through an automatic CBC analyzer, while serum collected from gel-vacutainers was analyzed for blood urea, blood urea nitrogen (BUN), creatinine and total bilirubin. Each parameter was compared between infected and un-infected animals using a paired t-test in Minitab Express™ software for statistical analyses. Results: Erythron comparison showed a highly significant (P [Open Vet J 2023; 13(11.000): 1400-1408]

The current study was carried out to screen 10 isolates (ARS-01–ARS-10) of Rhizoctonia. solani from potato tubers cv. Kuroda, which were collected from various potato fields in Multan, Pakistan. The isolates were found to be morphologically identical, as the hyphae exhibit the production of branches at right angles and acute angles often accompanied by septum near the emerging branches. Anastomosis grouping showed that these isolates belonged to AG-3. A pathogenicity test was performed against the susceptible Kuroda variety and among the isolates, ARS-05 exhibited the highest mean severity score of approximately 5.43, followed by ARS-09, which showed a mean severity score of about 3.67, indicating a moderate level of severity. On the lower end of the severity scale, isolates ARS-06 and ARS-07 displayed mean severity scores of approximately 0.53 and 0.57, respectively, suggesting minimal symptom severity. These mean severity scores offer insights into the varying degrees of symptom expression among the different isolates of R. solani under examination. PCoA indicates that the severe isolate causing black scurf on the Kuroda variety was AG-3. A comprehensive analysis of the distribution, genetic variability, and phylogenetic relationships of R. solani anastomosis groups (AGs) related to potato crops across diverse geographic regions was also performed to examine AG prevalence in various countries. AG-3 was identified as the most widespread group, prevalent in Sweden, China, and the USA. AG-5 showed prominence in Sweden and the USA, while AG-2-1 exhibited prevalence in China and Japan. The phylogenetic analysis unveiled two different clades: Clade I comprising AG-3 and Clade II encompassing AG-2, AG-4, and AG-5, further subdivided into three subclades. Although AGs clustered together regardless of origin, their genetic diversity revealed complex evolutionary patterns. The findings pave the way for region-specific disease management strategies to combat R. solani’s impact on potato crops.

Citrus viroid infection is emerging as a serious threat because of its efficient systemic movement within the host plant and its quick spread due to contaminated pruning tools. A survey was conducted to investigate the primary distribution and molecular characterization of Citrus bent leaf viroid (CBLVd) and its variants in different citrus cultivars. A total of 154 symptomatic citrus samples were collected and detected by RT‒PCR with newly designed specific primers with the incidence of 36.33%. During biological indexing study on Etrog citron, expressions of reduced leaf size, yellowing with a light green pattern, and bending were observed. Amplified products were sequenced and analyzed using a nucleotide BLAST search, which showed 98% homology with other CBLVd isolates. The results of the phylogenetic tree analysis showed the presence of two main groups (A and B), with the predominant variants of CBLVd, i.e., CVd-I-LSS (Citrus viroid Low Sequence Similarity) sequences, clustering in subgroup A1 along with newly detected CVd-I-LSS from Palestinian sweet lime (Citrus limettioides), which has been identified as a new host of CVd-I-LSS in Pakistan. Further analysis of the sequences in subgroup A1 showed that the variant of CVd-I-LSS infecting citrus cultivars had a close relationship with isolates reported from China, Japan, and Iran, which may have resulted from the exchange of planting material. This study also unveiled the variability in nucleotide sequences of CBLVd, which made it unable to be detected by old primers. The results of this study indicate that the widespread presence of divergent variants of CBLVd is a major concern for the citrus industry in Pakistan and other countries where virulent isolates of CBLVd are prevalent. These findings suggest the need for future research on effective management and quarantine measures to stop the spread of CBLVd.

Objectives: Plant-parasitic nematodes are a serious threat to global agricultural production worldwide. To avoid synthetic chemistries toxicity there is a dire need of the hour to develop innovative nematode control strategies. Biological control using the antagonistic fungi of the plants is considered very economical and environment friendly. Methods: Efficacy of different fungal filtrate concentrations was estimated towards the mortality and clutching of Meloidogyne javanica. To determine the antagonistic potential of Penicillium citrinum (MN518391), time of disclosure was assessed in the laboratory with the result “exposure to 8% filtrate for a clock (24 hrs.), expressively reduced the viable juveniles and hatched eggs. Results: Exposition to aforementioned filtrate of P. citrinum for a clock (24 hrs.) revealed that juvenile body turned into straight stature leading to reduction in viability of nematodes. Contrary to it most of nematodes exhibited bent body when exposed to Aspergillusniger (MK713445), or (MN513383) its filtrates. Among the various isolated antagonistic fungi, GC–MS analysis revealed 22 unique compounds e.g., quinazoline and its derivatives as the most prevalent and squalene as least occurring possess significant nematicidal properties against the rootknot nematodes. Conclusion: Hence, using antagonistic fungus from the described plans as BCAs in agriculture against plant-parasitic nematodes is a viable long-term biocontrol technique and provide future avenues in this area of research.

Deficiency of micronutrients is a major hurdle for achieving good quality mango fruit and sustainable optimum yield. High soil pH and phosphorus fertilizers are major causes that restrict the bioavailability of micronutrients, such as zinc (Zn) and boron (B). In addition, low or no micronutrient application may create severe Zn and B deficiency in fruits, especially mango. The judicious use of Zn and B is critical to overcoming this problem. Application of both nutrients in the form of soil and foliar application can increase the uptake of Zn and B and the yield of mango fruit on a sustainable basis. However, time is needed to synchronize micronutrients to application methods. Therefore, the current experiment was conducted to explore the best application rate of both micronutrients to the application method in mango orchards. There were 14 treatments applied with three replications. For micronutrient application, soil and foliar methods were chosen. Results showed that 75SB + 0.8FB + 150SZn + 1.0FZn perform significantly best for the improvement in the fruit length (62 %), fruit width (57 %), pulp fresh weight (92 %), stone weight (72 %). Furthermore, a significant increase in total soluble solids (45 %) and a decrease in acidity (50 %) confirmed the imperative functioning of 75SB + 0.8FB + 150SZn + 1.0FZn over control. Furthermore, a significant reduction in total phenolic contents and juice pH validated the effectiveness of 75SB + 0.8FB + 150SZn + 1.0FZn over control in mango. In conclusion, Zn and B soil and foliar application is a better approach for achieving good quality mango fruit. Treatment 75SB + 0.8FB + 150SZn + 1.0FZn is best for mango growers to achieve maximum fruit yield. However, more investigation is suggested in different climatic zones to declare 75SB + 0.8FB + 150SZn + 1.0FZn as the best application amendment to maximize the yield and quality of mango.

Plant tissue culture technique employed for the identification and isolation of bioactive phytocompounds has numerous industrial applications. It provides potential benefits for different industries which include food, pharmaceutical and cosmetics. Various agronomic crops i.e., cereals, fruits, vegetables, ornamental plants and forest trees are currently being used for in vitro propagation. Plant tissue culture coupled with biotechnological approaches leads towards sustainable agricultural development providing solutions to major food security issues. Plants are the rich source of phytochemicals with medicinal properties rendering them useful for the industrial production of pharmaceuticals and nutraceuticals. Furthermore, there are numerous plant compounds with application in the cosmetics industry. In addition to having moisturizing, anti‐ageing, anti‐wrinkle effects; plant-derived compounds also possess pharmacological properties such as antiviral, antimicrobial, antifungal, anticancer, antioxidant, anti-inflammatory, and anti-allergy characteristics. The in vitro propagation of industrially significant flora is gaining attention because of its several advantages over conventional plant propagation methods. One of the major advantages of this technique is the quick availability of food throughout the year, irrespective of the growing season, thus opening new opportunities to the producers and farmers. The sterile or endangered flora can also be conserved by plant micro propagation methods. Hence, plant tissue culture is an extremely efficient and cost-effective technique for biosynthetic studies and bio-production, biotransformation, or bioconversion of plant-derived compounds. However, there are certain limitations of in-vitro plant regeneration system including difficulties with continuous operation, product removal, and aseptic conditions. For sustainable industrial applications of in-vitro regenerated plants on a large scale, these constraints need to be addressed in future studies.

Zinc is one of the crucial micronutrients required for the sustenance of growth and metabolism in plants. Zinc deficiency results in growth inhibition and chlorosis in plants along with low production of carbohydrates, proteins, and chlorophyll. The utilization of zinc nanoparticles (ZnNPs) is an effective strategy to enhance growth in plants. The present investigation was carried out to determine the effect of green synthesized ZnNPs on the growth and yield of Pisum sativum L. Two pea varieties were raised in pots treated with various levels of ZnNPs. Zinc nanoparticles escalated the growth and yield of pea plants. Maximum growth and yield were obtained at 400 and 600 ppm as compared to control and zinc sulphated treated plants. In conclusion green synthesized zinc nanoparticles can enhance crop pea plant's growth and productivity. More investigations are suggested under variable agro-climatic zones for declaration of the best application rate between 400 and 600 ppm for different crops.

Management of zinc (Zn) in calcareous soils is a major problem for higher rice growth and yield. Need of time is to introduce environmentally friendly approach for the management of Zn. Inoculation of arbuscular mycorrhizae fungi (AMF) is one of such efficacious technique for enhancing the availability of Zn in these soils. The present study investigated the effect of different Zn application methods i.e., seed coating (SC; 1.25 g Zn/kg seed), seed priming (SP; 0.5 M solution) and soil application (SA; 4 mg ZnSO4/kg soil) alone or in combination with AMF applied in completely randomized design (CRD) on morpho-physiological growth and productivity of rice. Results showed that Zn SA + AMF remained significantly the best treatment for the improvement in germination, plant height, spike length and number of spikes than control + AMF and control with no AMF. A significant enhancement in 1000 grains weight (71.11%), total chlorophyll (40.38%), photosynthetic rate (16.17%) and transpiration rate (41.48%) validated the efficacious role of Zn SA + AMF over control + AMF. Significant increase in rice grains N (25.68 and 40.11%), P (29.41 and 25.00%), K (42.86 and 47.37%) and Zn (10.42 and 59.03%) signified the imperative functioning of Zn SA + AMF and Zn SA over control + AMF and control without AMF respectively. In conclusion, Zn SA has the potential to improve the rice growth nutrients uptake. However, Zn SA + AMF is better to approach than the sole application of Zn SA for rice. More investigations at the field level under different soil textures are suggested to declare Zn SA + AMF as the best treatment for improvement in the productivity of rice.

Rhizoctonia solani is one of the most common soil-borne fungal pathogens of legume crops worldwide. We collected rDNA-ITS sequences from NCBI GenBank, and the aim of this study was to examine the genetic diversity and phylogenetic relationships of various R. solani anastomosis groups (AGs) that are commonly associated with grain legumes (such as soybean, common bean, pea, peanut, cowpea, and chickpea) and forage legumes (including alfalfa and clover). Soybean is recognized as a host for multiple AGs, with AG-1 and AG-2 being extensively investigated. This is evidenced by the higher representation of sequences associated with these AGs in the NCBI GenBank. Other AGs documented in soybean include AG-4, AG-7, AG-11, AG-5, AG-6, and AG-9. Moreover, AG-4 has been extensively studied concerning its occurrence in chickpea, pea, peanut, and alfalfa. Research on the common bean has been primarily focused on AG-2, AG-4, and AG-1. Similarly, AG-1 has been the subject of extensive investigation in clover and cowpea. Collectively, AG-1, AG-2, and AG-4 have consistently been identified and studied across these diverse legume crops. The phylogenetic analysis of R. solani isolates across different legumes indicates that the distinct clades or subclades formed by the isolates correspond to their specific anastomosis groups (AGs) and subgroups, rather than being determined by their host legume crop. Additionally, there is a high degree of sequence similarity among isolates within the same clade or subclade. Principal coordinate analysis (PCoA) further supports this finding, as isolates belonging to the same AGs and/or subgroups cluster together, irrespective of their host legume. Therefore, the observed clustering of R. solani AGs and subgroups without a direct association with the host legume crop provides additional support for the concept of AGs in understanding the genetic relationships and evolution of R. solani.

Plant diseases are one of the major threats to global food production. Efficient monitoring and detection of plant pathogens are instrumental in restricting and effectively managing the spread of the disease and reducing the cost of pesticides. Traditional, molecular, and serological methods that are widely used for plant disease detection are often ineffective if not applied during the initial stages of pathogenesis, when no or very weak symptoms appear. Moreover, they are almost useless in acquiring spatialized diagnostic results on plant diseases. On the other hand, remote sensing (RS) techniques utilizing drones are very effective for the rapid identification of plant diseases in their early stages. Currently, drones, play a pivotal role in the monitoring of plant pathogen spread, detection, and diagnosis to ensure crops’ health status. The advantages of drone technology include high spatial resolution (as several sensors are carried aboard), high efficiency, usage flexibility, and more significantly, quick detection of plant diseases across a large area with low cost, reliability, and provision of high-resolution data. Drone technology employs an automated procedure that begins with gathering images of diseased plants using various sensors and cameras. After extracting features, image processing approaches use the appropriate traditional machine learning or deep learning algorithms. Features are extracted from images of leaves using edge detection and histogram equalization methods. Drones have many potential uses in agriculture, including reducing manual labor and increasing productivity. Drones may be able to provide early warning of plant diseases, allowing farmers to prevent costly crop failures.

Citrus canker (CC), caused by one of the most destructive subfamilies of the bacterial phytopathogen Xanthomonas citri subsp. Citri (Xcc), poses a serious threat to the significantly important citrus fruit crop grown worldwide. This has been the subject of ongoing epidemiological and disease management research. Currently, five different forms have been identified of CC, in which Canker A (Xanthomonas citri subsp. citri) being the most harmful and infecting the majority of citrus cultivars. Severe infection symptoms include leaf loss, premature fruit drop, dieback, severe fruit blemishing or discoloration, and a decrease in fruit quality. The infection spreads rapidly through wind, rain splash, and warm and humid climates. The study of the chromosomal and plasmid DNA of bacterium has revealed the evolutionary pattern among the pathovars, and research on the Xcc genome has advanced our understanding of how the bacteria specifically recognize and infect plants, spread within the host, and propagates itself. Quarantine or exclusion programs, which prohibit the introduction of infected citrus plant material into existing stock, are still in use. Other measures include eliminating sources of inoculum, using resistant hosts, applying copper spray for protection, and implementing windbreak systems. The main focus of this study is to highlight the most recent developments in the fields of Xcc pathogenesis, epidemiology, symptoms, detection and identification, host range, spread, susceptibility, and management. Additionally, it presents an analysis of the economic impact of this disease on the citrus industry and suggests strategies to reduce its spread, including the need for international collaboration and research to reduce the impact of this disease on the global citrus industry.

Plants often face incompatible growing environments like drought, salinity, cold, frost, and elevated temperatures that affect plant growth and development leading to low yield and, in worse circumstances, plant death. The arsenal of versatile compounds for plant consumption and structure is called metabolites, which allows them to develop strategies to stop enemies, fight pathogens, replace their competitors and go beyond environmental restraints. These elements are formed under particular abiotic stresses like flooding, heat, drought, cold, etc., and biotic stress such as a pathogenic attack, thus associated with survival strategy of plants. Stress responses of plants are vigorous and include multifaceted crosstalk between different levels of regulation, including regulation of metabolism and expression of genes for morphological and physiological adaptation. To date, many of these compounds and their biosynthetic pathways have been found in the plant kingdom. Metabolites like amino acids, phenolics, hormones, polyamines, compatible solutes, antioxidants, pathogen related proteins (PR proteins), etc. are crucial for growth, stress tolerance, and plant defense. This review focuses on promising metabolites involved in stress tolerance under severe conditions and events signaling the mediation of stress-induced metabolic changes are presented.

Mismanagement in foliar fertilizer application at different crop stages decreases the productivity of the crop. Likewise, higher application of phosphorus (P) beyond recommended application rates not only decrease zinc (Zn) uptake in rice but also increase fertilizer use cost. Inoculation of arbuscular mycorrhizae (AMF) may optimize the uptake of P and improve crops production via organic secretions. That's why the current study was conducted to examine the individual and coordinated effects of 0.5% Zn (0.5Zn) foliar spray (tillering (T) and/or panicle (P) initiation stage) and AMF application. Application of foliar 0.5Zn at tillering+panicle stage remained significantly better for significant enhancement in plant height, spike length, gas exchange attributes and total chlorophyll contents than control. A significant decrease in electrolyte leakage Also validated the effectiveness of treatment 0.5ZnT+P compared to control. Compared to control, the maximum increase in N (14.5 and 25.7%), P (42.1 and 33.3%), K (22.2 and 30.0%) and Zn (19.3 and 27.8%) accumulation was also found in 0.5ZnT+P, with and without AMF, respectively. In conclusion, 0.5ZnT+P with AMF is a better approach than sole application of Zn at tillering or panicle initiation stages. Nevertheless, more investigations are suggested at field level under variable climatic zones to confirm the effectiveness of 0.5ZnT+P with AMF for improvement in rice growth and production.

Elicitors are stressors that activate secondary pathways that lead to the increased production of bioactive molecules in plants. Different elicitors including the fungus Aspergillus niger (0.2 g/L), methyl jasmonate (MeJA, 100 µM/L), and silver nanoparticles (1 µg/L) were added, individually and in combination, in a hydroponic medium. The application of these elicitors in hydroponic culture significantly increased the concentration of photosynthetic pigments and total phenolic contents. The treatment with MeJA (methyl jasmonate) (100 µM/L) and the co-treatment of MeJA and AgNPs (silver nanoparticles) (100 µM/L + 1 µg/L) exhibited the highest chlorophyll a (29 µg g−1 FW) and chlorophyll b (33.6 µg g−1 FW) contents, respectively. The elicitor MeJA (100 µM/L) gave a substantial rise in chlorophyll a and b and total chlorophyll contents. Likewise, a significant rise in carotenoid contents (9 µg/g FW) was also observed when subjected to meJA (100 µM/L). For the phenolic content, the treatment with meJA (100 µM/L) proved to be very effective. Nevertheless, the highest production (431 µg/g FW) was observed when treated with AgNPs (1 µg/L). The treatments with various elicitors in this study had a significant effect on flavonoid and lignin content. The highest concentration of flavonoids and lignin was observed when MeJA (100 mM) was used as an elicitor, following a 72-h treatment period. Hence, for different plant metabolites, the treatment with meJA (100 µM/L) and a co-treatment of MeJA and AgNPs (100 µM/L + 1 µg/L) under prolonged exposure times of 120–144 h proved to be the most promising in the accretion of valuable bioactive molecules. The study opens new insights into the use of these elicitors, individually or in combination, by using different concentrations and compositions.

Rice (Oryza sativa L.) is an important crop that is grown worldwide to supply the world’s expanding food demand. In the current study, the effects of plant growth-promoting rhizobacteria (PGPR) and Arbuscular mycorrhizal fungi (AMF) on soil fertility and rice growth were explored. Rice plants were inoculated to evaluate how AMF fungi and PGPR affect various aspects of soil and plants, implicating abiotic stress tolerances. The experiment was carried out in a completely randomized design with three replicates under the controlled conditions. Results depicted that the plants that were inoculated with a mixture of AMF and PGPR had better yields and nutritional concentrations, while both AMF and PGPR lowered soil pH and organic matter differently. Similarly, AMF and PGPR treatments significantly increased the amount of N, P, K, and B in the post-harvest soil. The PGPR-inoculated plants had a 10–40% higher buildup of N in their tissues. Similarly, when they were compared with non-infected plants, AMF-inoculated treatments demonstrated a greater N accumulation in the rice tissue. The maximum P content in plant tissues was 0.149% in PGPR5-infected plants, either alone or in combination with AMF. In T12, AMF + PGPR5 inoculated rice plants, the maximum K uptake was 1.98%, which was 54% higher than the control treatment. The sole application of AMF raised K buildup in rice tissues by 38% compared with the control treatment. The improved productivity of plants with AMF and PGPR (especially with PGPR5) was attributed to the increased availability of nutrients in the soil. As a result, rice plant growth, yield, and essential element uptakes were boosted significantly. The present study’s results suggested using the combined application of AMF + PGPR5 for improving the rice yield and for sustaining the soil health.

Nanotechnology is a burning field of scientific interest for researchers in current era. Diverse plant materials are considered as potential tool in green chemistry based technologies for the synthesis of metal nanoparticles (NPs) to cope with the hazardous effects of synthetic chemicals, leading to severe abiotic climate change issues in today’s agriculture. This study aimed to determine the synthesis and characterization of metal-based nanoparticles using extracts of the selected plant Calotropis gigantea and to evaluate the enzyme-inhibition activities and antibacterial and antifungal activity of extracts of metal-based zinc nanoparticles using C. gigantea extracts. The crystal structure and surface morphology were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). C. gigantea was examined for antimicrobial activity against clinical isolates of bacteria and fungi. The water, ethanolic, and acetone extracts of C. gigantea were studied for their antagonistic action against bacterial strains (E. coli, S. aureus, P. multocida, and B. subtilis) and selected fungal strains (A. paracistic, F. solani, A. niger, S. ferrugenium, and R. nigricans). In vitro antimicrobial activity was determined by the disc diffusion method, where C. gigantea was tested for AChE and BChE inhibitory activity using Ellman’s methodology. The kinetic analysis was performed by the proverbial Berthelot reaction for urease inhibition. The results showed that out of all the extracts tested, ethanolic and water extracts possessed zinc nanoparticles. These extracts showed the maximum zone of inhibition against F. solani and P. multocida and the lowest against S. ferrugenium and B. subtilis. A potential source of AChE inhibitors is certainly provided by the abundance of plants in nature. Numerous phyto-constituents, such as AChE and BChE inhibitors, have been reported in this communication. Water extract was active and has the potential for in vitro AChE and BChE inhibitory activity. The urease inhibition with flower extracts of C. gigantea revealed zinc nanoparticles in water extracts that competitively inhibited urease enzymes. In the case of cholinesterase enzymes, it was inferred that the water extract and zinc nanoparticles have more potential for inhibition of BChE than AChE and urease inhibition. Furthermore, zinc nanoparticles with water extract are active inthe inhibition of the bacterial strains E. coli, S. aureus, and P. multocida and the fungal strains A. paracistic, F. solani, and A. niger.

Mango sudden death (MSD) or quick decline (QD) is the most destructive disease found in mango orchards of Pakistan and is characterized by collapse of the vascular system by Ceratocystis fimbriata and Lasiodiplodia theobromae. Cultural practices, chemicals, and biological control are the most valuable tools for the management of MSD, but the role of micronutrient deficiencies has remained an area that is heavily ignored by the farming community. To study the impact of micronutrients, four mango orchards were selected at different locations where different combinations of micronutrients, i.e., Zinc (Zn), Boran (B), and Copper (Cu) in the form of Zinc sulphate (ZnSO4), Borax/Boric acid (H3BO3), and Copper Sulphate (CuSO4), were applied both foliar and in drench along with the recommended doses of Nitrogen: Phosphorous: Potassium (NPK), and Farmyard manure (FYM), respectively. The quantities of micronutrients were determined from the soil and leaves before and after application of the treatments. The impact of micronutrients was measured in terms of reduction in disease severity and increase in fruit yield. The results revealed that the application of all three micronutrients both in soil drench and in foliar form significantly decreased the disease severity at three locations and increased the yield in all four mango orchards. Application of ZnSO4 (0.8%), +H3BO3 (0.8%), +CuSO4 (0.5%) and as soil drench ZnSO4 (400 g) + Borax (200 g) + CuSO4 200 g plant−1 proved to be the best treatments, with an average of 12.88 and 14.03% reduction in disease severity and with an average yield of 128 and 119 kg, respectively. The application of micronutrients would be a promising solution in an integrated disease management program used to tackle MSD.

Abstract Citrus tristeza virus (CTV) by killing millions of citrus cultivars grown on sour orange rootstock worldwide has become one of the most dangerous viral pathogen. Characterization of 12 CTV isolates was analyzed by biological indexing. Infected samples of citrus were collected from citrus growing areas of Pakistan and CTV was detected by symptoms on indicator plants and confirmed by direct tissue blot immunoassay (DTBIA). CTV positive samples were graft inoculated on six biological indicator hosts in the study. A standardized protocol was deployed to study biological characteristics of these isolates. All biological indicators induced mild and from mild to moderate reactions against all of the CTV isolates tested. About two isolates produced stem-pitting symptoms from moderate to severe on Mexican lime. CTV strains were further characterized and confirmed by the analysis of p25 gene of CTV isolates using single-strand conformation polymorphism (SSCP) assay. SSCP analysis revealed that most isolates confined only one predominant sequence variant. SSCP profiles of PCR amplified products from CTV isolates showed bands patterns corresponding to mild and sever strain. Three isolates (4MF, 8KBS and 10GS) from different regions and cultivars were identified as potential source of mild strains for cross protection. These results are the best base for mild strain cross protection (MSCP) in the country.

Abstract Huanglongbing (HLB), also known as citrus greening disease, is the most devastating disease of citrus across the world, caused by the phloem limited fastidious bacterium ‘Candidatus Liberibacter spp.’. This research was conducted on HLB infected 10-year-old Kinnow orchard located at Multan, Pakistan. Different classes of antibiotics in various combinations were applied on HLB-infected trees. The antibiotic treatments were applied before flowering in February, during fruit setting in April and at fruit growth stage in June. The different antibiotics combinations used were Ampicillin sodium + Rifampicin, Cefalexin + Rifampicin, Ampicillin sodium + Cefalexin, Ampicillin sodium + Cefalexin + Rifampicin and Control (distilled water). Different fruit qualitative and quantitative attributes were examined. The application of antibiotics significantly decreased 2–11% in flower, June and pre-harvest drops as compared to control. Further, antibiotics increased fruit weight and yield by five times while the juice content, total soluble solids, ripening index, total sugars, phenolic and vitamin C content were also increased in fruits. In addition, total soluble proteins, peroxidase and catalase activities were increased in fruits harvested from antibiotic treated plants compared to control, however the superoxidase dismutase activity was decreased in fruits of antibiotic treated plants. Finally, it is concluded that application of different antibiotics combinations helps in improving the fruit yield and different quality attributes of HLB infected Kinnow trees.

Cotton (Gossypium hirsutum) is a global cash crop which has gained importance in earning foreign exchange for each country. Bacterial blight caused by Xanthomonascitri subsp. malvacearum (Xcm) has been a seriousdisease in Pakistan’s cotton belt on multiple occasions. Bacterium was isolated and identified through various biochemical and diagnostic tests wherehypersensitivity reaction, Gram staining, KOH (potassium hydroxide), catalase, starch hydrolysis, lecithinase and Tween 80 hydrolysis tests confirmed bacterium as Gram-negative and plant pathogenic. Xcm perpetuation assays wereevaluated on various cotton varieties under glasshouse conditions in completely randomized design by three different methods, wherein the scratch method proved to be the best upon CIM-496 and showed 83.33% disease incidence as compared with the other two methods, where Bt-3701 responded with 53.33% incidence via the spray gun method, and 50% with the water splash method on CIM-616, as compared with the control. Similarly, for disease severity percentage, Bt-3701 was pragmatic with 47.21% through scratch method, whereas, in the spray gun method, 45.51% disease severity was noted upon Bt-802, and 31.27% was calculated on Cyto-179 through the water splash method. Owing to the unique antibacterial properties of aqueous plant extracts, the poison food technique showed Aloe vera, Mentha piperita, Syzygiumcumini and Azadirachta indica with 17.77, 29.33, 18.33 and 20.22 bacterial colonies counted on nutrient agarmedium petri plate, respectively, as compared with the control. Measurement of the inhibition zone by disk diffusion technique showed Mentha piperita, Syzygiumcumini, Citrus limon, Moringa oleifera and Syzygium aromaticum to present the most promising results by calculating the maximum diameter of the inhibition zone, viz., 8.58, 8.55, 8.52, 8.49 and 8.41 (mm), respectively, at the highest tested concentration (75 ppm, parts per million) compared with the control. It is probable that the decoction’s interaction with the pathogen population on the host plant will need to be considered in future experiments. However, at this moment, more research into the effective management of cotton bacterial blight by plant extracts in terms of concentration determination and development of biopesticides will provide future avenues to avoid environmental pollution.

Xanthomonas citri subsp. citri, a causative agent of the citrus canker (CC) disease, belongs to one of the essential groups of the bacterial phytopathogen family, Xanthomonadaceae. It has been a potential threat to the globally significant citrus fruit crop, which has remained under investigation for disease management and epidemiology since the 1980s. In Pakistan, the average yield of citrus is 11 t/ha, which is lower than other countries, including China, Brazil, and India, having average productions of 27, 26, and 22 tons/hectare, respectively. Citrus canker is one of the most devastating diseases, posing a significant threat to crop yield and fruit quality. To date, five distinct types (or forms) of the citrus canker have been recognized; the Asiatic (Canker A) form is most destructive and affects most citrus cultivars. Severe infection outcomes include dieback, defoliation, severely blemished fruit, premature fruit drop, and reduced fruit quality. The infection increases under humid, warm, cloudy climate, wind, and heavy rainfall. The analysis of plasmid and chromosomal DNA of X. citri subsp. citri depicted an evolutionary relationship among pathovars of Xanthomonas. The extensive study on the genome of X. citri subsp. citri has contributed to the current knowledge of plant host recognition of pathogens, host specificities, dissemination, and propagation. Regulatory programs, i.e., quarantine or exclusion, continued to be practiced, prohibiting infected citrus plant material into the existing stock. Other measures include removal of inoculums sources, resistant hosts, protective copper-containing sprays, and windbreak systems. In this review, we explored the latest trends in the areas of epidemiology, pathogenome, detection, host–pathogen interaction, biofilm formation, and management of X. citri subsp. citri.

Plants in nature are under the persistent intimidation of severe microbial diseases, threatening a sustainable food production system. Plant-bacterial pathogens are a major concern in the contemporary era, resulting in reduced plant growth and productivity. Plant antibiotics and chemical-based bactericides have been extensively used to evade plant bacterial diseases. To counteract this pressure, bacteria have evolved an array of resistance mechanisms, including innate and adaptive immune systems. The emergence of resistant bacteria and detrimental consequences of antimicrobial compounds on the environment and human health, accentuates the development of an alternative disease evacuation strategy. The phage cocktail therapy is a multidimensional approach effectively employed for the biocontrol of diverse resistant bacterial infections without affecting the fauna and flora. Phages engage a diverse set of counter defense strategies to undermine wide-ranging anti-phage defense mechanisms of bacterial pathogens. Microbial ecology, evolution, and dynamics of the interactions between phage and plant-bacterial pathogens lead to the engineering of robust phage cocktail therapeutics for the mitigation of devastating phytobacterial diseases. In this review, we highlight the concrete and fundamental determinants in the development and application of phage cocktails and their underlying mechanism, combating resistant plant-bacterial pathogens. Additionally, we provide recent advances in the use of phage cocktail therapy against phytobacteria for the biocontrol of devastating plant diseases.

ABSTRACT Bitter gourd is of great importance due to its usage against the treatment of numerous ailments in human beings. A comprehensive survey at four localities of Southern Punjab, Pakistan was carried out to determine the severity of Myrothecium leaf spot. Maximum disease severity was at C1 (Chak 11/NP) and least at C2 (Kot Mehtab). Among isolated species Myrothecium roridum was found more prevalent and pathogenic as compared to M. verrucaria. Antifungal activity using solvent extracts of five medicinal plants (Mangifera indica, Melia azedarach, Nicotiana tabacum, Moringa oleifera and Eucalyptus globosum) were evaluated against isolated species by agar well diffusion method at various concentrations (0.01, 0.10, 1.0 and 10.0 µg / mL). N. tabacum revealed maximum zone size (13.40 mm and 8.28 mm) with ethanol and chloroform solvents respectively followed by M. azedarach (9.00mm and 6.48mm). However, least inhibition was observed with ethanol and chloroform extracts of E. globosum (6.04mm and 3.88mm zone size respectively). Ethanol extracts showed highest activity when compared to chloroform extracts. Qualitative phytochemical analysis showed that all the selected plants are rich in chemical compounds such as alkaloids, terpenoids, flavonoids and phenols whereas Saponins was only present in N. tabacum while absent in rest of the extracts.