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The ability of salicylic acid and jasmonic acid to suppress post-harvest infection with green mould Penicillium digitatum and blue mould P. italicum on three citrus species Citrus reticulata ‘Kinnow’, C. limon ‘Meyer Lemon’, and C. limetta ‘Mosambi’ was evaluated in a dose-response study. Salicylic acid (SA) and jasmonic acid (JA) were applied to the fruits as a post-harvest dip treatment followed by wound inoculation with the pathogens. Both resistance inducers caused a significantly lower disease severity compared with the infected but non-treated control, whereas disease incidence was not significantly lower than in the control. The efficacy of both SA and JA in reducing disease severity was concentration-dependent; the use of higher concentrations resulted in a greater degree of suppression. All the Citrus species tested in this study showed different responses in terms of disease development. C. limon ‘Meyer Lemon’ showed the highest disease development, and C. limetta ‘Mosambi’ the lowest. To get an insight into the mechanisms underlying the increase in resistance, the activity of defence-related enzymes – peroxidase (POD) and polyphenol oxidase (PPO) – was recorded in SA- and JA-treated fruit peelings. The activity of both enzymes was directly proportional to the concentration of the SA and JA applications. The highest activity of PPO and POD was observed in C. reticulata ‘Kinnow’ and the lowest in C. limon ‘Meyer Lemon’ fruits. This study is the first to document an increase in the activity of PPO and POD in SA- and JA-treated Citrus species in the presence of blue mould and green mould pathogens.

Dieback of mango caused by Lasiodiplodia theobromae is among several diseases responsible for low crop production in Pakistan. To further complicate the issue, resistance in L. theobromae is emerging against different fungicides. L. theobromae was isolated from diseased samples of mango plants collected from various orchards in the Multan District. The efficacy of different fungicides viz. copper oxychloride, diethofencarb, pyrachlostrobin, carbendazim, difenoconazole, mancozeb, and thiophanate-methyl was evaluated in vitro using a poison food technique. Thiophanate-methyl at all concentrations was found to be the most effective among five systemic fungicides against L. theobromae, followed by carbendazim, difenoconazole and diethofencarb. The fungicides, i.e., thiophanate-methyl, difenoconazole, carbendazim and diethofencarb showed maximum efficacy with increasing concentration. The isolates of L. theobromae showed some resistance development against the tested fungicides when compared with previous work. These investigations provide new information about chemical selection for the control of holistic disease in mango growing zones of Pakistan.

Present investigation was planned to check the impact of bio (Cure, Azadirachtin) and synthetic (Cartap, Virtako) chemicals individually and concomitantly with fertilizers on the development of root knot nematode, Meloidogyne incognita and the growth of tomato (Solanum lycopersicum) plants. Tomato seedlings were transplanted in sterilized soil amended with Cartap, Virtako, Cure and Azadirachtin at their recommended doses and inoculated with 500 freshly hatched juveniles (J2s) of M. incognita. Data were recorded after 7, 14, 21 and 28 days to check the invasion and development stages. All the treatments significantly reduced invasion and subsequent development of M. incognita in roots. Different application methods regarding protective and curative were used to test the efficacy of Cartap, Virtako, Cure and Azadirachtin. Results revealed that Protective application of bio and synthetic chemicals was more effective at nematode suppression rather than being curative. Then the impact of bio and synthetic chemicals were tested in combination with NPK on nematode reproduction. Following treatments i.e. Virtako + NPK, Cartap + NPK, Cure + NPK, Azadirachtin + NPK, control (N) and control (H) with ten replications were applied in pots containing tomato seedlings. Inoculation of 2000 freshly hatched J2s of M. incognita was done. Results revealed that combined effect was more pronounced in reducing nematode reproduction and improving plant growth. Maximum number of J2s was recorded in nematode control (1241.0) while a dynamic decline was observed in Cartap+NPK, Virtako+NPK, Cure+NPK and Azadirachtin+NPK (144.4, 162.2, 198.1, 216.6) respectively. Combined application of selected chemicals with fertilizers not only reduced nematode reproduction but also improved plant growth. So, the integrated use of chemicals with fertilizers could be a successful tool in management strategies of root knot nematode. [ABSTRACT FROM AUTHOR]

A local strain of Volvariella volvacea Vv pk, locally known as Chinese mushroom was cultivated on six different agricultural wastes including paddy straw, cotton waste, banana leaves, corn stovers, sugarcane baggasse and pulses straw. The study was conducted to know that how much a substrate contributes in the nutritional value of the fruiting bodies of the mushroom harvested from such substrate and to recommend the best substrate for the commercial cultivation of the mushroom with high levels of protein, crude fibre and certain other elements. The biochemical analysis of the fruiting bodies harvested from the substrates was done to estimate the moisture percentage, crude fat, protein, fiber, and ash contents. Maximum protein (34.17%), ash (10.8) and crude fiber percentage (11.9%) was observed in the fruiting bodies harvested from cotton waste. So, cotton waste is recommended as an effective substrate to grow Chinese mushroom on commercial scale.

Citrus is known as a major fruit due to its high nutritional value and adaptability in tropical and sub-tropical regions. Among diseases, citrus dieback is one of the most threatening diseases in which overall plant growth is reduced. Major causes are Colletotrichum gloeosporioides and citrus nematode (Tylenchulus semipenetrans) with 15-35% losses all over the world. Plant material was established adopting sanitary measures in earthen pots (12-inch diameter). Fresh culture of C. gloeosporioides and T. semipenetrans was prepared for the inoculation by following the standard procedures. In the first set, rootstocks were inoculated with 200mL of water having spore suspension of C. gloeosporioides while in in the second set, inoculation of T. semipenetrans was done by using 45 mL of water suspension having 2000 freshly hatched juveniles per pot, while at the rate of 1 × 107 spores/mL per plant. In the third set, the interaction of C. gloeosporioides and T. semipenetrans was studied by inoculating selected citrus rootstocks by both pathogens. After four months of inoculation, data were recorded on plant disease index (PDI) along with plant growth parameters (root weight, shoot weight, shoot weight, shoot length and number of leaves). Trifoliate orange and cox mandarin hybrid showed resistance against the development of T. semipenetrans while rough lemon, C-35 Citrange and sour orange were found susceptible. There was a significant difference in plant growth parameters between inoculated and healthy plants. Root weight and shoot weight decreased by 8.98g and 11.53g, while root length and shoot length decreased by 7.29cm and 13.5cm respectively as compared to control treatments in most susceptible rootstocks. Per cent Branch Infection (PBI) and per cent Disease Index (PDI) were maximum (71.52, 37) per cent on rough lemon respectively. Results regarding combined inoculation of C. gloeosporioides and T. semipenetrans showed that there was a significant difference in plant growth parameters between inoculated and healthy plants. In rough lemon, Root weight and shoot weight decreased by 13.86 and 20.57g respectively in diseased and healthy plants. Root length and shoot length decreased by 8.37 and 20.04cm respectively as compared to control treatments in most susceptible rootstocks. Overall results depicted that inoculation of both pathogens reduced plant growth more severely as compared to their individual application. [ABSTRACT FROM AUTHOR]

Cotton is an important cash crop of Pakistan and is severely affected with wilt in cotton-growing areas of Punjab province. Research was carried out on two major pathogens of cotton Fusarium oxysporum f. sp. vasinfectum and Meloidogyne incognita and their possible role in wilt disease complex. During 2017-19, a survey of cotton growing areas of Punjab (Jhang, Multan, Vehari, Mianwali, Rahim Yar Khan, Bahawalpur, Kabir Wala, Dakota, Basti Dharik, Tibba Sultan Pur, Rajan Pur, Chak 27 (Layyah), Chak 99B (Layyah), Lodhran, Fateh Pur and Dagar Rohtass) was conducted to collect a sample on symptomology basis of yellowing of leaves, discoloured bark of lower part of the stem, blackened xylem vessel and wilting. Data were recorded on wilt disease incidence, prevalence, associated pathogens and root-knot nematodes. Prevalence of cotton wilt was recorded the maximum 85% in areas of Vehari, Kabir Wala and Rajan Pur while the maximum incidence in both Multan and Tibba Sultan Pur was 15%. Percentage association of wilting fungi was recorded from the soil, roots, stem and leaves on placing them in artificial media and soil dilution techniques were used to determine fungi in rhizosphere such as Fusarium oxysporum, Verticillium spp., Penicillium spp., Aspergillus spp., Rhizoctonia spp., Colletotrichum spp., Rhizopus spp., Mucor and Pythium. Root associated fungi were isolated by Hyphal tip method and isolated F. oxysporum, Rhizoctonia spp. and Pythium spp. From stem and leaf sample, F. oxysporum, Verticillium spp., Colletotrichum spp., Alternaria spp. and Botryodiplodia spp. were recorded. Relative density nematode was recorded from different locations and highest occurrence was observed in Bahawalpur (85%) by using different extraction methods. Eggs masses of root knot nematodes were staining by using Phloxin B and nematodes inside root system was done by using acid fuchsin. Nematode reproduction parameters like No. of J2/roots system, J2 in 100ml of soils, eggs masses/root system, females/roots system, galls/root system were recorded. Cotton wilt caused by the interaction of Fusarium and Root knot nematode is threat to cotton industry in Pakistan and it should be treated to avoid economic losses. [ABSTRACT FROM AUTHOR]

Meloidogyne incognita (Kofoid and White) Chitwood (MI) is a potential threat to tomato (Solanum lycopersicum L.) production. In this study, the inhibitory effect of Moringa oleifera L. (MO) extracts and Steinernema kraussei Steiner (SK) as stand-alone treatments and in combination was assessed to suppress the reproduction and development of MI. Highly susceptible variety of tomato cv. 'Money Maker' was tested for the invasion and development of MI. Aqueous and ethanolic MO extracts were tested in combination with SK at three different concentrations and time intervals. After 12-h 'S' concentration of aqueous MO extract + ethanolic MO extract + SK produced 100% juvenile mortality while the treatment MO + SK caused the least juvenile mortality of MI. Juvenile mortality was increased in a time-dependent manner. Aqueous MO extract + ethanolic MO extract + SK produced 100% egg hatching inhibition at standard 'S' concentration. Plant growth was significantly enhanced in plants treated with MO extracts, SK and their combinations compared to MI treated control plants. The total number of infective juveniles/g root and soil, galls, egg masses, females were highest in MI treated plants while lowest in plants treated with a combination of MI + SK + aqueous MO + ethanolic MO after 60 days of inoculation. SK and MO has demonstrated significant potential to suppress MI infection. Therefore, further investigations should focus on their efficacy at field level to prevent the infection of MI. [ABSTRACT FROM AUTHOR]

Several fungal plant pathogens are posing serious threat to the Ficus spp. grown as an ornamental plant for landscaping world over. Dieback disease is one of the major limiting factors in Ficus spp selection and cultivation as an ornamental plant. Typical Dieback disease symptoms were recorded on Ficus plantation from different commercial ornamental plant growing nurseries and several other landscape areas of Punjab, Pakistan. A prospective etiological study was planned and conducted using certain basic and molecular methods. Frequently associated Fusarium spp. were tested for pathogenicity confirmation using Koch’s postulates on Ficus benjamina L. Among these tested fungal isolates, FMB-45-Fi was proved as principal cause of dieback on Ficus species. The pathogenic isolate was subjected to molecular characterization by exploring three genomic regions (ITS, TEF1-α and RPBII). Molecular data validated the pathogenic isolate as Fusarium proliferatum. Here, we documented Fusarium proliferatum as causative agent of dieback in Ficus spp. in Punjab Pakistan and it is a first record to the best of our knowledge. [ABSTRACT FROM AUTHOR]

Being sessile organisms, plants are continuously challenged by phytopathogenic fungi, contributing the largest share in loss due to plant disease. Plants naturally possess a well-developed and programmed protein-based defense system, capable of producing antimicrobial cationic peptides to ward off pathogen attack. Numerous genes encoding antifungal proteins have been isolated, cloned, sequenced and transgenically expressed against multiple phytopathogenic fungi successfully. Genetic engineering technology has been widely utilized to produce transgenic plants with enhanced resistance against pathogens. Pathogenesis-related proteins (PR-proteins) is a group of the most important inducible defense-related antifungal proteins, including defensins, thionins, osomtin-like proteins, thaumatin-like proteins, chitinases, glucanases, oxalate oxidase or oxalate oxidase-like proteins and lipid transfer proteins. Transgenic plants have been developed by imparting the artificial expression of genes encoding antifungal PR-proteins. The expression of transgenes belonging to a single group of PR-proteins or synergistic action of transgenes from different groups has greatly uplifted the level of defense response in plants against fungi. Transgenic expression of antifungal PR-proteins has led to remarkably enhanced resistance in transgenic plants. In this review, we have summarized the role of PR-proteins in plant defense against fungi and 15 years of success achieved so far to generate a variety of transgenic plants resistant against fungi through overexpression of transgenes from different groups of PR-proteins. [ABSTRACT FROM AUTHOR]