PENICILLIUM AS PLANT PATHOGEN

Major crop infections are caused by fungi secretarial for almost 70% of pliyto diseases. Some fungal plant pathogen invades the plant tissues antagonistically, killing the host cells to obtain nutrients is known as necro- trophic (necros means death and trophic means feeding). Some of these fungi begin an intricate feeding with living host cells, and these fungal pathogens are known as biotrophic (McKeever and Chastagner, 2016). During the last two decades, it has been seen as a cumulative number of contagious infectious diseases in natural populations and accomplished landscapes. In both plants and animals, an extraordinary sum of fungal and fungal-like diseases has recently triggered some of the most spartan dieoffs and exterminations ever perceived in wild species and are threatening food security. Human actions are escalating fungal disease spreading by altering natural environments and thus fashioning new opportunities for evolution. We argue that nascent fungal infections will cause collective attrition of biodiversity, with wider allegations for human, ecosystem health, atrd agriculture.

Pemcillium causes a destructive fruit rot of citrus. Early symptoms include a soft water-soaked area on the peel, followed by the expansion of a circular colony of white mold, up to 4 cm diameter after 24-36 hours at 24°C. Green asexual spores (conidia) form at the epicenter of the colony, surrounded by a broad band of white mycelium. The lesion spreads more rapidly. The fruit rapidly spoils and collapses or in lower humidities shrinks and mummifies. Grey mold, blue mold, and green mold caused by Botrytis cinerea, Penicillium italicum, Penicillium digitatum, respectively, are common postharvest diseases of fruits and vegetables (Gatto et al., 2011).

4.6.1 PENICILLIUM ROT

Penicillium rot can be perceived in the field, but most often, it develops after harvest and can result in crop losses of up to 90%. It develops well at relatively high temperatures during storage, but it can continue to grow, although more slowly, even at temperatures close to freezing. More than a few species of Penicillium can be the source for causing blue mold. These fungi are common saprophytes on plant debris and senescent plant tissue (Naik et al., 2017). The incursion of pomegranate fruit can arise through wounds or bruises, but colonization habimally occurs on the surface of senescent fruit. The mycelium cultivates inside the fruit through the connective tissue and arils at progressive stages. High relative humidity and moderate temperatures of 70 to 77°F (21-25°C) favors the optimum growth. Penicillium rot or blue mold is one of the most communal and straightforwardly predictable post-harvest rots of apple but is not inevitably responsible for large losses. Its implication has amplified in current years since it produces a mycotoxin, patulin, which transpires in Penicillium- rotted fruit and afterward in fruit juice produced from discarded fruit (Oteiza et al., 2017). Penicillium vermoesenii is the contributory agent of a disease of palms, generally termed pink bud rot (Lopez-Llorca et al., 1994). The fungus has been observed in several species of palms (Hodel, 1985; Aragaki et al., 1991), normally causing necrosis and sunken lesions on new leaves. However, in moist conditions, the fungus spomlates heavily, forming pink pulverulent masses. If the infection reaches the central bud, it may even cause the death of the palm (Bliss, 1938; Hodel, 1985). Penicillium oxalicum grew on stubs left after fruit pick, leaf, and side- shoot trimming, which cause the stem softening and sneering (O’Neill et al., 1991). Brown ring tissue of the main stem is the general spot for the blue-green mold of Penicillium spp. and sporulation is perceived. Healthy fruits are generally resistance to infection for P oxalicum but when the fruit is damaged, it becomes an aggressive pathogen and rot developing more speedily at 20°C and above than at 15°C (Hu et al., 2017).

The life cycle and epidemiology take in airborne or waterborne spores attacking fruit through wounds, bruises, or cracks anywhere they find a place on the surface of the fruit and is often the secondary trespasser of other rots. Though there are fallen fruits in the orchard under the trees, Penicillium rot is seldomly seen. Because of these, there are no predicting approaches that are technologically advanced or monitoring system applicable to it. The fungus is pervasive, and contamination will always occur if the fruit is spoiled or not handled appropriately. P implication is an anamorph species that cause post-harvest rot on pomegranate fruit. All apple varieties are vulnerable, but it is most frequently perceived on Bramley in store. The fungus grounds a pale green to dark brown circular soft rot, which binges quickly over the fruit exterior and into the flesh, creating a sharp crossing point between the healthy and rotted tissue, such that the rot can be bundled out. Mature cuts are roofed in brilliant white furuncles, which swiftly turn blue. P expansum subsists on desiccated fruit, or fruit jiffs stuck on loose bins or lying around storage or pack- house areas. Furthermost, wound infections in storage are consequences due to water-borne spores in post-harvest drench solutions (e.g., antiscald agents) or in water cascades used to grade fruit (Bafort et al., 2017). Penicillium digitatum a phytopathogen causes Penicillium rot on papaya (Borras and Aguilar, 1990; Bautista-Banos et al., 2003).

4.6.2 BLUEAND GREEN MOLD

Blue mold or bluish-green mold are generally belonging to Penicillium, the very same mold from which the penicillin antibiotic is prepared. Normally the blue colored mold grows on food, but it can be also found on the household belongings that have been damaged by water like wallpaper, insulation, and carpeting. Along with these household materials, blue mold can also be found on furnishings like couch cushions and mattresses that have formerly suffered water damage. Health problems can be caused by inhaling the spores from the blue colored mold, which include allergic reactions, inflammation of the lungs, and sinus infections. People with circumstances like asthma and emphysema are more prone to mold-related complaints, as are the very young and the very old, but anybody can be exaggerated (Tzortzakis et al., 2017).

You can get rid of mold from non-porous surfaces like glass, metal, bath-tubs, toilets, and tile floors with an antimicrobial cleanser (Foster 40-80). It’s typically not likely to eliminate mold entirely from porous surfaces, though, such as wood, ceiling tiles, drywall, insulation, and carpeting. Those materials will prerequisite to be indifferent from the home-very cautiously, in order to prevent scattering of mold to other areas during the removal process-and substituted with noninfected materials. You should put on an N-95 respirator mask while washing up mold in order to defend yourself from breath in any microscopic mold spores, which can later cause health problems (Nolte et al., 2002).

Two species of Penicillium are mainly responsible for causing mold, i.e., Penicillium digitatum, which causes the green mold and P. italicum causes blue mold. In these diseases softening of damaged tissue occurs. After softening white fungal growth results, which progressively turns blue or green as spores develop. Postharvest fungicides can arrest spore development resulting in white only fungal growth (Eckert et al., 1985). Initially, the infections can occur through an open area and then results into the developing of damaged areas. The progress of mold proliferations is directly related with storage temperatures (up to an optimum of 27°C). Late season fruit more susceptible to have an infection, and even damaged rind is more susceptible (Nguyen et al., 2017).

Careful handling of fruits can reduce the damage to the rind. Good hygiene conditions and sorting reduces spore load and infection rates in the fruits. Regular sanitation helps in destroying the spores in recirculating water and packing line equipment. Postharvest fungicides applied within 24 hours of harvest can also reduce the chances. And even low-temperatures storage can slow down the growth of fungi (Harkema et al., 2017).

OVERCOMING PENICILLIUM INFECTIONS IN PLANTS

As we all know that safety concerns first in all fields. As one of them is pertaining towards fungi and the mycotoxins contamination in agriculture has been an issue of key apprehension. Today, with widely available reports and updated databases on fungal occurrence and mycotoxins contamination, we can overcome problems related with them. Fanners need to control the plant diseases in order to preserve the superiority and richness of food, fiber, and feed. Plant diseases can be prevented by different tactics that can even control that. Though there are decent agronomic and horticultural practices, fanners mostly rely heavily on pesticides and chemical fertilizer. Such involvements to agriculture have contributed expressively to the remarkable enhancements in crop productivity and value over the past decade (Miflin, 2000). There are lot of environmental pollution that have been caused by the disproportionate use and mismanagement of agrochemicals, which has led to significant changes in people’s attitudes in the direction of the practice of pesticides in agriculture. At the moment, there are firm regulations on chemical pesticide usage, and there is political pressure to eliminate the most hazardous chemicals from the marketplace (Reddy et al., 2009). Moreover, the binge of plant diseases in natural ecosystems may exclude efficacious usage of chemicals, for the reason that the scale to which such practice might have to be functional. Subsequently, some pest management researchers have engrossed their efforts on evolving alternative inputs to artificial chemicals for controlling pests besides diseases. These substitutes are referred as biological controls. An assortment of biological controls is accessible for practice, nevertheless further progress and effective espousal are obligatory to realize greater thoughtful of the complex communications among plants, people, and the environment (Cadotte et al., 2017).

Biological control agents (BCA) are the organisms that overwhelm the pathogen or pest. Even the same term can be used for the natural product that might be extracted (or sometime even fermented) from various sources that can inhibit the pathogen or pest (Yousuf et al., 2016).

These preparations may be very simple combinations of natural components with specific activities or multifaceted assortments with multiple effects on the target pest or pathogen as well as on the host. Suppression of plant infection can be overcome in numerous ways, if growers’ activities care made applicable, rotations, and planting of disease-resistant culti- vars (naturally selected or genetically engineered) can be practiced. As biological control results from many diverse types of interactions among organisms, researchers have engrossed on characterizing how the mechanisms are operated. For instance. Pseudomonas is well-known to yield the antibiotic 2,4-diacetylphloroglucinol (DAPG) may also persuade host defenses (Iavicoli et al., 2003). Furthermore, DAPG-producers can rapidly colonize the roots, a trait that can additionally contribute their capability to overwhelm pathogen commotion in the rhizosphere of wheat through rivalry of organic nutrients (Weller et al., 2002).

Sunflower seeds (Helianthus animus L.) are cultivated extensively for oil production, as the seeds are known to have rich polyunsaturated fatty-acids (65% linoleic acid) that contain low level of saturated fats and along with that sunflower seeds are also a decent source of dietaiy fiber, minerals, and vitamin E and it has also been testified to have harbor mold caused by Penicillium chrysogenum (Pozzi et al., 2005). Preharvest applications of thiophanate methyl (TM) controlled postharvest green mold consistently. Lessening of chemical pesticide usage including chemicals that control the soil-bome plant pathogens is extensively rummage-sale in agriculture. Biocontrol microbes can be applied to the seeds directly or to the soil former to planting possibly will take possession of the spermo- sphere along with or without rhizosphere of saplings and thus may thwart surrounding infection of soil-bome pathogens. Therefore, biocontrol agents may contribute in various ways of trophic and noil-trophic interface mechanisms, which consist of production of antifungal compounds, restless parasitism of pathogens, the incentive of host plant defenses, or else competitive colonization of spennosphere and in addition rhizosphere substrates (Weller, 1998).

 
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