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The occurrence of chestnut blight (Cryphonectria parasitica) was studied in 2011-2012 at 13 locations in the main chestnut growing areas of Romania. Infections were detected at four localities. The symptoms and the fungus were detected on European chestnut (four localities) and also on oak trees (two localities). A total of 89 isolates of C. parasitica were isolated and characterised. Based on canker and isolate morphology (culture morphology and the Bavendamm test), both virulent and hypovirulent samples were isolated; hypovirulent isolates were found at only one locality. Two vegetative compatibility types corresponding to EU-12 and EU-2 were identified among isolates. Both mating types were found, with a dominance of MAT-1 in southern Romania and MAT-2 in northern Romania.

Field validation of spot-fumigation with phosphine (PH₃) applied by a subcontracted pest-control company in a farm grain store infested by pests was conducted. Inside and outside of the fumigated grain spot, containers with adults of 5 species of coleopteran stored-product pests were regularly spaced. The beetle pests were the internally feeding Sitophilus granarius and Rhyzopertha dominica, and the externally feeding Tribolium castaneum, Oryzaephilus surinamensis, and Cryptolestes ferrugineus. A 100% mortality of all pest species inside the fumigated spot under the sheet used for the application was stated. The efficacy (maximal) sharply declined with the increasing distance from the fumigated spot: 50% mortality was observed at 5 m from the spot, 38% mortality at 10 m, and a mortality of 23% was observed at 15 m. Mortality was different among the species, and the most sensitive was O. surinamensis, whereas the most tolerant were S. granarius, R. dominica, and T. castaneum. Although an efficient fumigation within the spot was found, the efficacy was low in the grains surrounding the spot. The practical implications of the findings are discussed.

The presence of seed-borne viruses in winter squash landraces in the Black Sea region of Turkey were detected. The seed samples of landraces were tested by ELISA for Cucumber mosaic virus (CMV), Zucchini yellow mosaic virus (ZYMV), Squash mosaic virus (SqMV), Tobacco ring spot virus (TRSV), and Cucumber green mottle mosaic virus (CGMMV). Based on the ELISA results, 11.3% of the samples were infected with the viruses; ELISA, CMV was found at the rate of 5.1% in the winter squash samples, while incidence of ZYMV was determined as 6.2%. Moreover, none of the plants germinated from seeds were found to be infected with SqMV, TRSV, and CGMMV. This is for the first time that seed-borne viruses of winter squash landraces have been identified in the Black Sea region of Turkey.

Seedlings of Trifolium pratense L. cultivars were mechanically inoculated with Czech isolates of Alfalfa mosaic virus (AMV), Clover yellow mosaic virus (ClYMV), Clover yellow vein virus (ClYVV), Red clover mottle virus (RCMV), White clover mosaic virus (WClMV), and a newly discovered member of the Cytorhabdovirus genus. WClMV infected 75.4% of clover seedlings; cv. Rezista was the most susceptible (93.3%), while cv. Fresko was the least susceptible (58.3%). RCMV infected 59.6% of plants; the most susceptible was cv. Tempus (77.6%), the least susceptible cv. Sprint (38.3%). While WClMV infected a higher number of seedlings, RCMV revealed more severe symptoms on affected plants. On the basis of ELISA and RT-PCR results, no cultivar was susceptible to mechanical inoculation with ClYMV and cytorhabdovirus. Moreover, cvs Fresko and Sprint were not susceptible to ClYVV and AMV, respectively.

Effect in reducing maize plant height using growth regulators ethephon, chlormequat chloride (CCC), CCC + ethephon, and mepiquat chloride + prohexadione-Ca was studied in field experiments during 2010 and 2011. It was found that maize plant height could be reduced by as much as 125 cm (49% of control) using a double application of ethephon (576 g a.i./ha) at growth stages BBCH 18-19 and BBCH 34-36. The other growth regulators displayed weak or no influence. An optimum level of shortening was achieved using ethephon (576 g a.i./ha) at BBCH 34-36 (reducing plant height by 40-90 cm), but it is necessary to count upon yield loss of 0.5-0.6 t/ha.

The spread pattern of Abutilon theophrasti (velvetleaf) in Austria, the Czech Republic, and Slovakia was analysed based on an exhaustive distribution data set (389 records). Cumulative number of all records showed a continuous increase since its introduction in the 19^th century and > 1970 its spread gained momentum with an exponential increase > 2000. In fields, the species remained rare until 2000. Since then, A. theophrasti has invaded fields much more frequently (78% of all records in fields > 2000) and it was mainly found in sugar beet and maize. Approximately a total of 188 000 ha of the agricultural area are currently at risk of being invaded. Given the on-going spread into fields, the results provide evidence that A. theophrasti may cause serious impacts. Control measures should focus on the prevention of spreading seeds and the establishment of new foci.

In 2014, the journal Plant Protection Science (PPS) completes 50 years of publication (1965-2014). However, its roots extend back to the year 1921. Today, it is an international scientific journal focused on all aspects of plant protection sciences, fully published in English. This occasion offers a fitting opportunity to describe some of the most important historical stages of the journal's development. In our brief historical overview, we summarise the changes in journal title, chief-editors, and editorial policy during the last fifty years, and with an examination of its importance, scope and readership. We present analyses of the journal's development, some for the entire period of 1965-2013, while others are limited to more recent decades. The journal's present place among the world's scientific journals is documented by analyses in the international citation databases, BIOSIS CI, SCOPUS, and WOS. An analysis of three particular citation databases were made in October 2013, while the overall period 1998-2013 was conducted from All Databases/Thomson Reuters in March 2014. PPS is also included in other, important technical-literature databases, including Czech Agricultural and Food Bibliography, AGRIS/FAO database, AGRICOLA, CAB Abstracts, Current Contents, and Zoological Abstracts. Information about all of them is available in Ulrich's WEB database. In the final part of this paper, we summarise some recent achievements of the journal, and discuss some key topics related to its future development.

Communities of xylotrophic fungi were studied in wood of Pinus mugo of different qualities: (i) living stems, (ii) cut stumps, (iii) burned snags, (iv) cut burned stumps, (v) stems recently killed by root rot, and (vi) old snags of root rot-killed trees. A total of 277 isolates representing 58 fungal taxa were obtained from 300 wood samples (50 samples per each substrate category). Results of the present study suggested that following different disturbances (tree felling, forest fire or root rot), fungal communities likely evolve in different directions: depending on its origin (cut, burned or killed by the disease), dead wood might be inhabited by principally different microbial assemblages, and that fire has less effect on community structures than tree felling or root rot.

The fungus Fusarium oxysporum f.sp. pisi (FOP), the pea wilt pathogen, causes appreciable yield losses under favourable environmental conditions in Algeria. Studies on the pathogen variability and distribution of races are essential to identify effective sources of resistance to this disease. In this study, a survey was conducted during the period 2007-2011 in four different agro-climatic zones. Pathogenic variability in 52 isolates of FOP, collected from different pea-growing areas of western Algeria, were evaluated using 7 genotypes as differential hosts. Results indicated that the disease was prevalent in all fields prospected and isolates obtained were assigned to Races 1, 2, 5 or 6 by their pathogenicity. It was found out that Races 1 and 2 were more common in all areas with 61.5 and 19.2%, respectively. This study is the first report of pea Fusarium wilt races distribution in Algeria.

In the period 2009-2011 monitoring of the incidence of phoma stem canker was carried out at selected sites of the Czech Republic (Šumperk and Opava regions in North Moravia). The risk of infection was evaluated by assessing the autumn release of Leptosphaeria spp. ascospores and with the proPlant prediction model. In recent years, the incidence of phoma stem canker has been relatively low and this corresponded with the total count of ascospores released in the autumn period but not with an increased level of infection risk announced by the proPlant model. During the monitored period the ascospore concentration reached maximally 2 ascospores/1 m³ per day. Maximum ascospore release was recorded in 2010 as a result of favourable weather conditions. The first incidence of phoma leaf spot has been observed in mid-October. The higher values of ascospores concentration were recorded in the Opava region, but the total number of the trapped ascospores was more often higher in the Šumperk region.

In experiments using Petri dishes in the laboratory and pots in a greenhouse and climate chamber, we examined the influence of seed treatment on emergence of poppy. Four types of fungi (Alternaria spp., Dendryphion penicillatum, Fusarium spp., and Penicillium spp.) were detected on poppy seeds, with the highest infection rate being 72% for D. penicillatum. Surface disinfection decreased infection rate chiefly in D. penicillatum (by 32%) and in Alternaria spp. (by 16%). Seed treatment increased emergence by 9-10% in laboratory experiments but by only 0-6% in greenhouse experiments. Temperature plays an important role in emergence. In climate chamber experiments at a stable temperature of 12°C, the seed treatments increased emergence by 8-16%.

The pathogenicity of entomopathogenic fungi, Beauveria bassiana, Metarhizum anisopilae and Lecanicillium lecanii, was evaluated against adults of the olive fly Bactrocera oleae (Gmelin) under laboratory conditions by two ways, contact bioassays and oral bioassays. The results showed that oral bioassays caused higher mortality after four treatments than the used contact bioassays. Moreover, the virulence ofL. lecanii was higher than the virulence of B. bassiana and M. anisopilae in both ways of experiment. Lethal time (LT₅₀) was shorter in oral bioassays than in contact bioassays in all treatments. It was 14.67, 8.30 and 5.43 days for B. bassiana, M. anisopilae and L. lecanii with oral treatment while it was 16.6, 26.07 and 12.59 days for B. bassiana, M. anisopilae and L. lecanii, respectively, with contact treatment. The slope values were 2.41, 2.55 and 2.37 for contact bioassays and 1.64, 1.69 and 1.61 for oral bioassays of B. bassiana, M. anisopilaeand L. lecanii, respectively. The mortality response to the interaction between B. bassiana and M. anisopilae was synergistic while the interaction between B. bassiana + L. lecanii and M. anisopilae + L. lecanii showed an antagonistic response.

The efficacy of twelve sodium salts as possible alternatives to synthetic fungicides for the control of onion basal rot caused by Fusarium oxysporum f.sp. cepae was evaluated. In vitro tests showed that there were significant differences between the inhibitory effects of sodium salts on the mycelial growth (P ≤ 0.05) and 2% (w/v) concentrations of sodium metabisulfite and sodium fluoride completely inhibited mycelial growth of the fungus, while other salts did not. Sodium metabisulfite and sodium phosphate monobasic had lower pH values than the other salts. Unlike sodium metabisulfite, sodium phosphate monobasic could not decrease the mycelial growth. The ED₅₀, minimum inhibition concentration (MIC), and minimum fungicidal concentration (MFC) values indicated that sodium metabisulfite was more inhibitory to the fungus compared to sodium fluoride. In soil tests, inhibitory effect of sodium metabisulfite on the fungus was higher than that of sodium fluoride, where sodium metabisulfite completely inhibited mycelial growth at even 0.4% concentration.

The distribution of Plum pox virus (PPV), Prune dwarf virus (PDV), Prunus necrotic ringspot virus (PNRSV), Apple chlorotic ringspot virus (ACLSV) and Apple mosaic virus (ApMV) in naturally growing shrubs of blackthorn and road-bordering trees of plum and myrobalan, and of PPV, PDV, PNRSV and Cherry leafroll virus (CLRV) in sweet and sour cherry trees were investigated. The most widely distributed viruses were PPV in plums (74% of the investigated trees were infected); PPV, PDV, and PNRSV in myrobalans (26%, 11% and 18%, respectively), PDV in blackthorns (27%), and PDV and PNRSV in cherries (25% and 22%). PPV was not detected in sweet and sour cherries. The incidence of ACLSV and ApMV was negligible in individually growing trees of the genus Prunus in the Czech Republic.

Bromus tectorum is a highly invasive annual grass. The fungal pathogen Pyrenophora semeniperda can kill a large fraction of B. tectorum seeds. Outcomes in this pathosystem are often determined by the speed of seed germination. In this paper we extend previous efforts to describe the pathosystem by characterising secondary dormancy acquisition of B. tectorum. In the laboratory approximately 80% of seeds incubated at -1.0 MPa became dormant. In the field, seeds were placed in the seed bank in late autumn, retrieved monthly and dormancy status determined. The field study confirmed the laboratory results; ungerminated seeds became increasingly dormant. Our data suggest that secondary dormancy is much more likely to occur at xeric sites.

In 2007-2012 the first detailed study of P. halstedii distribution and severity was performed in the Czech Republic by monitoring altogether 128 localities. Incidence of the pathogen was recorded at seven localities in south-eastern (Central and South Moravia) and central parts (East and Central Bohemia) of the country; at only four localities the occurrence of sunflower downy mildew symptoms and pathogen sporulation were recorded repeatedly. In all cases the primary infection prevailed, and the severity of infections was rather low. The majority of records were for sunflower experimental fields (e.g. fields of Central Institute for Supervising and Testing in Agriculture. Brno-Chrlice, Czech Republic), one record came from a commercial field and one record from a hobby field. Results of surveys indicate that reservoirs of primary inoculum likely exist in the soil contaminated by P. halstedii oospores in these habitats, but additional transfer by infected seed may be possible. Historical and geographical consequences of recorded infections are discussed, as well as virulence variation in the Czech pathogen populations which is currently in the process of investigation.

Sixty-four apple cultivars and selections of potential interest to apple producers and plant breeders in the Czech Republic were tested for their relative resistance to the fire blight pathogen over six years. Level of fire blight resistance was evaluated according to the extent of lesion development on the shoots tips after artificial inoculation in experimental plots under insectproof nets. Cultivars Quinte (resistant) and Yellow transparent (high susceptible) were included in the tests. Of 64 apple cultivars and selections tested, none were high resistant, 3.1% were evaluated as resistant, 10.9% moderately resistant, 57.8% moderately susceptible, 21.9% susceptible and 6.3% high susceptible. Resistant apple genotypes, showing blight necrosis of shoots of 11-12%, were only cultivars Selena and Quinte. Moderately resistant genotypes (blight necrosis 13.1-25.0%) were Kordona, Golden Smoothee, Julia, HL 323, Melodie, HL 421 and S 634/3. High susceptible genotypes (blight necrosis more then 80.1%) were comprised cultivars Vesna, Topas, Yellow transparent and Vanda. The remaining genotypes were moderately susceptible (blight necrosis 26.1-60.0%) and susceptible (blight necrosis 60.1-80.0%). During six experimental years, quantitative variability was recorded in the blight score. Differences between cultivars in susceptibility to fire blight were often statistically significant.

The morphology and biology of immature stages and the distinguishing characters of generations in summer are briefly reviewed. The time of migration of the overwintered generation and the use of the median flight time are given. The longevity of overwintered adults, and the start and course of oviposition by overwintered females were observed mainly during June and July. The interval between adult emergence and flights from carrots appears to be very short, 2-3 days. Departure from developmental summer host plants culminates at the beginning of September. The sex ratio of the overwintered generation is not persistent, since it is usually female-biased. In emerged adults in summer the ratio is 50:50, with weak protandry. The systemic action of sucking for the curling of leaves was found by Láska already in 1964. Inliterature records, both subspecies of Daucus carota dominate as developmental hosts, more recently Coriandrum sativum was shown to be more suitable than Petroselinum hortense. Norway spruce, and to a lesser extent other conifers, are predominantly mentioned as overwintering shelter plants. It is not clear how overwintering occurs in regions without coniferous forests, and only undefined shrubs or trees are given in the literature. The first damage was reported inDenmark about in 1896, spreading from about 1918 over just a few years to the other Fennoscandian countries, and later in some other European countries. The spring migration is discussed, which occurs in central and northern Europe on the same date, perhaps explicable by the orientation of this pest or its particular populations to long days, despite the climate and phenology of each region. It is hypothesised that a particularly aggressive race evolved inSjaelland (Denmark) at the turn of the nineteenth and twentieth century, which later spread to other regions of northern and centralEurope.

The study was focused on the wild pathosystem Lactuca serriola-lettuce downy mildew (Bremia lactucae) and lettuce powdery mildew (Golovinomyces cichoracearum). Observations were focused mainly on recording natural infection of prickly lettuce (Lactuca serriola) by downy and powdery mildews in the East Bohemia and Moravia (the Czech Republic) in the May-September period of 2007-2011, and on the influence of environmental conditions on disease incidence. Only data for July and August were used for the detailed comparisons of occurrence of both pathogens, because intensity of disease in this period was the highest. Data were linked with the average monthly temperature and rainfall rate in the Czech Republic. G. cichoracearum prefers rather low levels of precipitation and temperatures around 20°C, therefore significantly higher incidence of this pathogen was recorded in August 2007. On the other hand in July 2009 and 2010, when the intensities of precipitation were higher, incidence of Bremia lactucae prevailed. In August 2010 and 2011 incidence of both pathogens were more or less similar at all locations. Our observations showed that climatic conditions influence the incidence and prevalence of both pathogens in weedy growing populations of Lactuca serriola.

Most of the vegetable crops are known to depend upon arbuscular mycorrhizal fungal (AM) symbiosis for growth and development, since AM fungi provide nutrients and water in exchange for photosynthates. The influences of AM fungi (Glomus intraradices (G) and Acaulospora laevis (A)) with Trichoderma viride (T) and Pseudomonas fluorescens (P) alone and in combinations on growth, mycorrhization, chlorophyll content, nutrient uptakes, and yield of broccoli plants were studied in pot culture under glasshouse conditions. The obtained results demonstrated that the single inoculation of broccoli plants with T. viride significantly increased the above ground fresh weight, root length, chlorophyll b, head diameter, root phosphorus, and shoot nitrogen in comparison to uninoculated control plants. On the other hand, consortium of G+A+T+P significantly increased plant height, above ground dry weight, root fresh weight, chlorophyll a, head fresh weight, and root nitrogen content. Similarly, G+T showed maximum leaf area, and P alone showed maximum uptake of shoot phosphorus. Whereas when P was supplied along with T, early flowering was recorded. AM fungal colonisation was negligible and only root tips were found infected in G or A treated plants which confirms low dependency of broccoli on AM fungi.

Identification of Meligethes species and their frequencies in adult samples collected at different localities in Central and South Moravia (Czech Republic, 2009-2011) was based on comparisons of morphometric and colour characters and on differences in male and female genitalia. M. aeneus, M. viridescens, M. subaeneus, M. atratus, and M. coracinus were recorded throughout the observation period, while M. nigrescens was recorded just in 2009 and 2011, M. carinulatus and M. maurus in 2010 and 2011. M. aeneus was the most frequent species of all compared samples (2009-2011). Of the accompanying species, M. subaeneus and M. viridescens were markedly more frequent in this study. Considering high resistance of M. aeneus to esteric pyrethroids, it could be helpful to distinguish among the individual Meligethes species occurring in field samples intended for laboratory testing.

In Europe, glyphosate resistant populations have developed in some weed species in perennial crops, including three species of the genus Conyza documented by the International Survey of Herbicide Resistant Weeds. Conyza spp. biology is reviewed in this paper and related to population dynamics and the development of resistant populations. Suboptimal growth stage at application, improper agricultural practices such as overreliance on glyphosate and long-term use of sublethal doses are identified as the most important factors of resistance development. Current control methods in perennial crops including mixtures of glyphosate with other active ingredients are discussed and effective weed management strategies are described to manage the development and spread of glyphosate resistant Conyza spp. in Europe.

Occurrences of pea aphids and their natural enemies (syrphids, mummies caused by entomopathogenic fungi Beauveria sp. and by the parasitic wasp Aphidius ervi) were compared in monocultures and mixtures of field peas and spring cereals in three seasons (2008-2010). At the beginning of colonisation, the occurrence of aphids was not substantially influenced by intercropping with cereals. However, the numbers of pea aphids located on inflorescences started to decline earlier in mixtures compared with monoculture. More syrphids (eggs + larvae) were found in mixtures than in monoculture, and more syrphid eggs were found in young aphid colonies (10 to 20 individuals) in mixtures. Intercropping did not influence the occurrence of fungal mummies (Beauveria sp.), but mixtures tended to have more aphid colonies infested by A. ervi in 2008 and 2009.

A particularly advantageous method of monitoring the flight and calculating the median was used. An example is given in order to understand better the calculation. The medians show that the timing is similar at different latitudes despite local phenological differences. The difference in median flight times between Finland and the Czech Republic was five days on average, but phenological differences are about a month, shown by a comparison of temperatures, the monitoring of buds on spruce, and by the stage of the carrot plants. During the attack by T. apicalis the carrot plants are younger towards north what is unusual in Psyllidae. In extreme north locations as Finland the genetic triggering for flight could not be realised by the strong declining of temperatures. Flight occurs here substantially later as to local photoperiodicity but is the earliest as to phenology, including carrot plants. The very small plants during flight are much more damaged here than the well-developed plants in central Europe.

Spilanthes acmella (Asteraceae) is an endangered ornamental cum medicinal annual herb. This study reports on the effect of two arbuscular mycorrhizal fungi (Glomus mosseae and Acaulospora laevis) applied either alone or in combination on post-transplanting performance of micropropagated S. acmella. Complete plantlets of S. acmella were raised by direct organogenesis from nodal explants on Murashige and Skoog medium supplemented with various cytokinins. S. acmella plantlets responded to all three mycorrhizal treatments in a significantly different way. G. mosseae enhanced the survival rate of S. acmella plantlets to 100%. Plant height, plant spread, number of branches per plant, number of leaves per plant, leaf area, biomass production, and chlorophyll content were significantly higher in AM inoculated plantlets as compared to the uninoculated ones. This clearly demonstrates that AM inoculation improved not only the survival rate of micropropagated plantlets but also their growth and biomass yield.

Field efficacy of neem (Azadirachta indica A. Juss) for managing soil arthropods and Cercospora leaf spots damage to peanut was studied in Ghana from 2008 to 2010. Treatments consisted of neem kernel water extract (NKWE) and neem kernel powder (NKP) applied separately as soil drench at the rates of 10.5 and 21.0 kg/ha at either planting or pegging. Untreated control and chlorpyrifos treatment at pegging were included as checks. Results showed generally that the neem products at the concentrations tested were efficacious and comparable to chlorpyrifos in lowering populations of soil arthropods and severity of leaf spot diseases, leaf defoliation, and scarified and bored pod damage, resulting in increased pod yield in 2008 and 2009.

The potential of antagonistic rhizobacteria in the management of bacterial blight of cotton caused by Xanthomonas axonopodis pv. malvacearum (Xam) was evaluated under greenhouse and field conditions. In this study, 93 bacterial isolates from the rhizosphere of cotton were screened for their efficacy in inhibiting the growth of Xam in vitro. Among them, 21 isolates were found to inhibit the in vitro growth of Xam. These isolates were identified as Pseudomonas fluorescens and Bacillus subtilis based on phenotypic characteristics, biochemical properties and using 16S-23S intergenic transcribed spacer-Polymerase Chain Reaction (PCR). Among the 21 isolates, the isolates P. fluorescens Pf32 and P. fluorescens Pf93 and B. subtilis B49 exhibited the maximum inhibitory activity against Xam. Talc-based powder formulations of the effective antagonistic isolates of P. fluorescens (Pf32, Pf93) and B. subtilis (B49) were developed and evaluated individually and in combination for their efficacy in the management of bacterial blight of cotton under greenhouse and field conditions. The P. fluorescens isolates Pf32 and Pf93 and Bacillus subtilis isolate B49 survived well in the talc-based formulation for more than 90 days. The application of a mixture of Pf32, Pf93 and B49 to seed, soil and foliage significantly reduced the bacterial blight incidence and increased the plant height, number of branches and number of bolls under field conditions. The plots treated with a mixture of Pf32, Pf93 and B49 recorded the maximum yield of 1915 kg/ha and 1512 kg/ha in trial I and trial II compared to 1210 kg/ha and 987 kg/ha in the untreated control, respectively.

Monitoring of species spectrum of true bugs (Heteroptera) on apple trees without pest management was conducted in 2010-2011. Two sites were selected - an abandoned orchard and a road alley near the village of Velké Bílovice (Břeclav district, Czech Republic). The capture of true bugs with a fogger device (Pulsfog) on five selected trees in each site was performed. The effective substance deltamethrin at concentration of 0.0025 g/l was applied to the tree crowns. Three collections (28/4, 20/5, and 9/7) in 2010 and two (11/5 and 23/6) in 2011 were done. Out of 55 detected species of true bugs, 43 species occurred in the alley and 29 in the orchard. Thirty-two species were predatory or partly predatory (58.18%), 22 species were phytophagous (40%), and one mycetophagous (1.82%).

Gloriosa superba is a medicinal plant severely infested with soil-borne Macrophomina phaseolina (Tassi) Goid. Under in vitro conditions a commercial formulation of Trichoderma viride and Pseudomonas fluorescens inhibited the mycelial growth of M. phaseolina isolates. Among the oil cake, mahua cake at 10% completely inhibited the mycelial growth of the M. phaseolina isolates. Under field conditions both the soil and foliar application of biocontrol agents is attributed to the healthy growth of G. superba crops by controlling the tuber rot disease and ultimately boosting the colchicine content.