Antagonism and Effect of Volatile Metabolites of Trichoderma spp. on Cladosporium spp.

ABSTRACT

Pecan is susceptible to the occurrence of diseases capable of harming its development, and leaf spot caused by Cladosporium spp is among them. Therefore, the objective of this work was to analyze the potential antagonist and in vitro effect of volatile metabolites of Trichodermaspp. On Cladosporium spp. isolated from pecan leaf spots. Three Cladosporium spp. isolates and two commercial products based on Trichodermaspp. were used, as well as an isolate of the same genus provided by the 'ElocyMinussi' Laboratory of Phytopathology at UFSM. Cladosporium spp. mycelial growth was monitored in order to evaluate the morphological characteristics of the pathogen. The use of Trichoderma spp. as biocontrol was assessed through dual culture tests and production of volatile metabolites. Trichoderma spp. showed positive results in inhibiting the growth of Cladosporium spp., thereby presenting potential to be used as a biocontrol agent.

Keywords:  biological control; dual culture tests; antibiosis; biocontrol agents

1. INTRODUCTION

Caryaillinoinensis (Wangenh) C. Koch is commonly known as a pecan tree, and is a fruit species of temperate climate native to North America, where it is naturally established close to water courses. In Brazil, the species cultivation took place between the 1960s and 1970s, when orchards were implanted through fiscal incentives, mainly in the Southern and Southeastern regions (Ortiz & Camargo, 2005). Its cultivation has currently been expanding, and therefore information regarding diseases that affect the species is necessary.

One of the diseases recently reported in pecan trees is the leaf spot caused by species of the genus Cladosporium, including C. pseudocladosporioides, C. cladosporioides, and C. subuliforme. The main symptoms found are dark circular spots (Walker et al., 2016a), which affect leaves and fruits. Another species of this genus, Cladosporium caryigenum, has been associated with pecan scab, which is the main disease that attacks this crop (Ortiz & Camargo, 2005).

Considering that the pecan leaf spot (Cladosporium spp.) has affected cultivars and that there are no commercial products for disease control registered for this crop, there is lack of research in this area. Biological control appears as an interesting possibility, considering that it is a control method less harmful to the environment.

Among the most used antagonistic fungi to control pathogens, species of the genus Trichoderma stand out, which are natural soil inhabitants and present characteristics like fast growth and abundant sporulation (Howell, 2003). They act as biocontrol agents through some mechanisms such as antibiosis, which is characterized by the production of volatile or non-volatile antibiotic substances with fungicidal effects capable of inhibiting the mycelium growth; mycopredatism, which involves the action of enzymes capable of causing the death of one of the fungi that will serve as food for the survivor; and the competition for space and nutrients, represented by the dispute in search of food, physical space, and sunlight (Benítez et al., 2004; Ribeiro, 2009; Dias et al., 2013).

Thus, the present study aimed to evaluate the antagonist potential by in vitro tests through dual culture test and the production of volatile metabolites by Trichoderma spp. on Cladosporium spp., which is the causal agent of the leaf spot disease in Caryaillinoinensis.

2. MATERIAL AND METHODS

Three Cladosporium spp. isolates (6SC, 12/7PR and 16/2RS) provided by the “ElocyMinussi” Laboratory of Phytopathology - Federal University of Santa Maria were used in this study, which were stored according to the method of Castellani (distilled water) (Castellani, 1939) and previously purified in monosporic culture.

Isolates used were pathogenic to pecan trees, which were obtained from leaves that presented leaf spot symptoms collected from orchards located in municipalities of the three states of southern Brazil (Table 1) (Walker et al., 2016b).

Table 1
Cladosporium spp. isolates obtained from pecan tree leaf spots (Caryaillinoinensis) in southern Brazil.

Isolate	Species	Collection Date	Municipality/State	Coordinates (GMS)	GenBank Access Number
6SC	Cladosporium pseudocladosporioides	Jan/14	Palmitos – SC	-27º12'00” S, -53º22'10” W	KT991538
12/7PR	Cladosporium cladosporioides	Mar/14	Porto Amazonas – PR	-25º32'22” S, -49º54'24” W	KT991547
16/2RS	Cladosporium subuliforme	Apr/14	Cachoeira do Sul – RS	-30º00'20” S, -53º52'00” W	KT995114

• (Walker et al. 2016b).

Two commercial products were used for tests using biocontroller: Biotrich^® (from Trichoderma spp.), Ecotrich^® (from T. harzianum) and one isolate (T4 UFSM), made available by the fungi collection of the “Elocy Minussi” Laboratory, Federal University of Santa Maria, which was obtained from an analysis of the fungal population of soil classified as a Sand Loam Soil (Durigon et al., 2014).

2.1. Mycelial growth of Cladosporium spp.

It is possible to observe the time required for the growth of Cladosporium spp. isolates through the mycelial growth test. Thus, it was possible to estimate the incubation period for subsequent tests.

To do so, an aliquot of 0.10 μL of spore suspension of each Cladosporium spp. isolate, adjusted to 1 x 10⁶ conidia/mL^-1 was inoculated at the center of Petri dishes (80 mm diameter) containing Potato Dextrose Agar (PDA) culture medium. After inoculation, plates were transferred to Biological Oxygen Demand (B.O.D.) incubation chamber at temperature of 25ºC and 12-hour photoperiod. Four replicates were made, each consisting of one plate. After 24 hours of incubation, the diameter of colonies was measured, which were performed in diametrically opposite directions with the aid of a digital caliper, resulting in an average of two readings. Readings were performed daily and completed at 23 days when colony growth completely occupied the plaque diameter, and according to the fastest growing species.

Data were submitted to analysis of variance and analyzed by linear regression using the Sisvar version 5.3 statistical software (Ferreira, 2009).

2.2. Antagonism of Trichoderma spp. against Cladosporium spp. under direct confrontation

First, Cladosporium spp. isolates (6SC, 2/7PR and 16/RS) and the sources of Trichodermaspp. were grown in PDA medium for 7 days at 25°C and 12-hour photoperiod.

The spore suspension of Cladosporium spp. isolates was subsequently adjusted to 1 x 10⁶ conidia/mL^-1. Subsequently, an aliquot of 0.10 μL of the spore suspension was inoculated into Petri dishes (80 mm in diameter) containing PDA, 0.5 cm away from the edges. Dishes were sealed and incubated at 25°C with 12-hour photoperiod for 7 days. After this period, 0.10 μL of the Trichoderma spp. spore suspension at the same concentration were added to the opposite side of the dish containing Cladosporium spp. isolates (adapted from Machado & Silva, 2013). Dishes were again sealed and transferred to incubation chamber at 25°C with 12-hour photoperiod for 7 days. Petri dishes inoculated with only the spore suspension of each pathogen isolate were used as control.

From the second day, the diameter of Cladosporium spp. isolates was daily measured throughout the incubation period in diametrically opposite directions with the aid of a digital caliper.

The following treatments were used: T1 - 6SC (C. pseudocladosporioides); T2 - 2/7PR (C. cladosporioides); T3 - 16/2RS (C. subuliforme); T4 - Biotrich^® x 6SC; T5 -Biotrich® x 12/7PR; T6 - Biotrich^® x 16/2RS; T7 -Ecotrich^® x 6SC; T8 - Ecotrich® x 12/7PR; T9 - Ecotrich^® x 16/2RS; T10 - T4UFSM x 6SC; T11 - T4UFSM x 12/7PR and T12 - T4UFSM x 16/2RS. Four replicates were used for each treatment, in which each replicate was composed of a Petri dish.

The mycelial growth inhibition percentage was calculated according to the formula (Equation 1):

$\%ofinhibition=\left[\frac{\left(R1-R2\right)}{R1}\right]\times 100$ (1)

In which: R1 = radial growth of control; R2 = radial growth of treatment (Jeyaseelan et al., 2012).

The scale proposed by Bell et al. (1982) was also used, which assigns classes varying from 1 to 5 depending on the antagonist's performance. Class 1 is used when the antagonist occupies the entire Petri dish ;class 2 when the antagonist covers 2/3 of the dish reaching part of the pathogen; class 3 when the antagonist and the pathogen overgrow up to the middle of the dish, and none of the fungus dominates the other; class 4, the pathogen grows up to approximately 2/3 of the dish, partially covering the antagonist; and class 5, the pathogen completely overgrows the dish.

The experimental design was completely randomized, and the means were compared by the Tukey test at 5% error probability, using the Sisvar version 5.3 statistical software (Ferreira, 2009).

2.3. Inhibitory effect of volatile metabolites produced by Trichoderma spp. on Cladosporium spp.

Assays were performed based on the methodology described by Dennis & Webster (1971) and adapted in order to assess the inhibitory potential of volatile metabolites produced by Trichodermaspp. The same treatments used for the dual culture test were performed.

First, the spore suspension of Cladosporium spp. isolates was adjusted to 1 x 10⁶ conidia/mL^-1. Subsequently, a 0.10 μL aliquot of the spore suspension was inoculated into Petri dishes (80 mm in diameter) containing PDA. Plates were then sealed and incubated for 7 days at 25°C with 12-hour photoperiod. After this period, 0.10 μL of the antagonist spore suspension were inoculated into the center of new Petri dishes with the same dimensions and also containing PDA medium. The lids of dishes containing Cladosporium spp. isolates were subsequently removed and the bases containing antagonists and pathogens were mixed together using Parafilm®. Bases were overlain so that the antagonist remained on the lower/bottom surface and dishes were then incubated under the same temperature and photoperiod conditions mentioned above. As control, base containing the pathogen overlapped with another containing only PDA medium was used.

Four replicates were used for each treatment, each replicate consisting of the union of two Petri dish bases. Daily pathogen colony measurements were carried out using a digital caliper throughout the 7 days of incubation. The experimental design was completely randomized and means were compared by the Tukey test at 5% error probability using the Sisvar version 5.3 statistical software (Ferreira, 2009).

3. RESULTS AND DISCUSSION

3.1. Mycelial growth of Cladosporium spp.

Analyzing the mycelial growth of different Cladosporium spp. isolates, it was verified that there is a growth disparity between 6SC and 16/2RS isolates, in which both obtained colony diameter of approximately 71 mm at 23 days of evaluation in relation to 12/7PR isolate, which at the same time period presented diameter of approximately 50 mm (Figure 1). Thus, it could be inferred that C. cladosporioides species (12/7PR) has lower growth rate than C. pseudocladosporioides (6SC) and C. subuliforme (16/2RS) species, which seems to be an important morphological characteristic that distinguish them.

Figure 1
Regression analysis of Cladosporium spp. colonies cultivated in PDA culture medium at 25°C and 12-h photoperiod.

According to Bensch et al. (2010), the three species used in this study are part of the Cladosporium cladosporioides complex, which includes similar species, but with some specific morphological characteristics capable of distinguishing them.

In analyzing the mycelial growth of C. cladosporioides species, Pereira et al. (2005) characterized isolates obtained from coffee tree fruits (Coffea arabica L.) and found that the diameter of colonies did not exceed 30 mm when grown in malt extract at 25°C for 10 days of incubation. Bataszkowski et al. (2005) cultivated C. cladosporioides isolates at room temperature and PDA culture medium and found colonies of approximately 55 mm for 10 days of incubation.

The test result using malt extract as culture medium and incubation temperature of 25°C for 10 days (Pereira et al., 2005) was similar to values obtained in the present study, where isolates cultured in PDA medium at 25°C presented mycelial growth of approximately 30 mm for 10 days of culture. However, in comparing the results obtained by Bataszkowski et al. (2005) using PDA culture medium and incubation at room temperature with results of this study, a difference can be verified, since the first study presented colonies of 55 mm of diameter for the same culture period, while colonies with diameter of 30 mm were observed in the present study. These differences in growth may occur due to factors such as composition of the culture medium, temperature and luminosity conditions, which are of paramount importance in determining the quality and quantity of characteristics such as mycelial growth and sporulation, and which are extremely important for the morphological differentiation of phytopathogens (Dhingra & Sinclair, 1995).

Bensch et al. (2010) analyzed the mycelial growth of C. pseudocladosporioides isolates grown in MEA (malt extract) and PDA over a 14-day period, which resulted in colony diameter ranging from 52 to 75 mm and from 65 to 78 mm, respectively. These results corroborated those obtained in the present study, in which mycelial growth of about 65 mm was found for 14 days of incubation in PDA medium.

On the other hand and regarding C. Subuliforme species, no studies analyzing characteristics such as mycelial growth and sporulation were found in literature due to the recent discovery of the species (Walker et al., 2016a).

3.2. Dual culture tests between Cladosporium spp. and Trichoderma spp.

In dual culture tests, Trichoderma spp. isolate (T4UFSM) and Biotrich^® and Ecotrich^® compounds are potential biocontrol agents when evaluated by the class scale proposed by Bell et al. (1982). All treatments obtained class equal to 1.0, corresponding to the complete occupation of the dish by the antagonist (Table 2).

Table 2
Averages of the dual culture test between Trichoderma spp. and Cladosporium spp. using the scale of scores proposed by Bell et al. (1982).

Cladosporium spp.	Trichodermaspp.
	Biotrich®	Ecotrich®	T4UFSM
6SC	1.0	1.0	1.0
12/7PR	1.0	1.0	1.0
16/2RS	1.0	1.0	1.0

While testing the antagonistic action of bioprotectors based on Trichoderma spp. for controlling Cylindrocladium candelabrum, Maciel et al. (2012) concluded that Trichodermaspp.-based bioprotectors reached scores ranging from 1 to 2.25 according to the scale proposed by Bell et al. (1982), which proved to be efficient in the control of Cladosporium spp. isolated from pecan trees.

Ethur (2006) tested the antagonist potential of Trichoderma spp. isolates over Fusarium solani and Fusarium oxysporum isolates. The results found were considered efficient in reaching scores from 1 to 2.5 according to the scale of Bell et al. (1982). The author also classifies scores with values between 1 and 2 as very efficient for the in vitro control of pathogens.

By calculating the mycelial growth inhibition percentage of the antagonist over the pathogen (Table 3), it was observed that the lowest percentage value was found for 6SC isolate (C. pseudocladosporioides) with mean value of 16.48%, followed by 12/7PR (C. cladosporioides) and 16/2RS (C. subuliforme) isolates, with mean values of 18.38 and 28.14%, respectively. On the other hand, the compound from Trichoderma spp. with the greatest effectiveness in the test was Ecotrich®, inhibiting 20.87, 22.86 and 28.95% the mycelial growth of 6SC, 12/7PR and 16/2RS isolates, respectively.

Table 3
Inhibition percentage of in vitro mycelial growth of Cladosporium spp. in the dual culture test with Trichoderma spp.

Cladosporiumspp.	Trichoderma spp.
	Biotrich®	Ecotrich®	T4UFSM	Test.
6SC	15.44	20.87	13.12	0
12/7PR	17.15	22.86	15.13	0
16/2RS	28.78	28.95	26.69	0

Some authors report the effectiveness of using Trichoderma spp. as antagonist for inhibiting the mycelial growth of pathogens. Studies carried out by Silva et al. (2008), for example, consisted in evaluating the inhibition percentage of T. stromaticum, T. viride, T. virens and T. harzianuma gainst Phytophthora citrophthora, obtaining percentages of 52.21, 42.81, 30.35 and 15.18%, respectively. In testing the inhibition percentage at 8, 16 and 24 days of treatment of Trichoderma spp. isolates on Mycosphaerellafijiensis Morelet isolate, which causes Black Sigatoka in Banana (Musa spp.), Vega et al. (2006) found significant results ranging from 14.41 to 73.48%, 23.21 to 62.05% and 12.25 to 55.44% at 8, 16 and 24 days of evaluation, respectively.

The results previously mentioned corroborate those found in the present study, in which the Ecotrich® was able to inhibit 28.95% of the pathogen growth corresponding to approximately 1/3, thus demonstrating the efficiency of Trichoderma as a biocontrol agent.

In relation to the mycelial growth of the pathogen in the direct confrontation test, significant difference in the mycelial growth of Cladosporium spp. in the presence of the antagonist was observed when compared to control (Figure 2).

Figure 2
Dual culture tests using formulations and Trichoderma spp. isolate on the different Cladosporium spp. species in PDA medium. Where: Letters correspond to the different treatments used. “A”: 6SC x Biotrich®; “B”: 6SC x T4UFSM; “C”: 6SC x Ecotrich®; “D”: 6SC; “E”: 12 / 7PR x Biotrich®; “F”: 12 / 7PR x T4UFSM; “G”: 12 / 7PR x Ecotrich®; “H”: 12 / 7PR; “I”: 16 / 2RS x Biotrich®; “J”: 16 / 2RS x T4UFSM; “K”: 16 / 2RS x Ecotrich®; “L”: 16 / 2RS.

The 6SC isolate (C. pseudocladosporioides) presented greater mycelial growth, statistically differing from the other species, with values from 43.34 to 47.58 mm when compared to Ecotrich® and the T4UFSM isolate, respectively, in comparison to control, with 54.36 mm. However, Trichoderma spp. isolates did not differ statistically among themselves with the exception of when tested with 6SC isolate, where commercial product Ecotrich® was superior to T4UFSM isolate; however, they did not differ statistically from Biotrich® and all were considered effective when compared to control (Table 4).

Table 4
In vitro mycelial growth of Cladosporium spp. in the dual culture test with Trichoderma spp. isolates.

Cladosporium spp.	Trichoderma spp.
	Biotrich®	Ecotrich®	TUFSM	Test.
6SC	45.63 aBC*	43.34 aC	47.58 aB	54.36 aA
12/7PR	29.55 cB	27.52 cB	30.27 cB	35.67 bA
16/2RS	38.71 bB	38.62 bB	39.85 bB	54.36 aA
C.V	4.23

• (*) means followed by the same lower-case letter in vertical lines and upper-case letters in horizontal lines do not differ from each other by the Tukey test at 5% error probability; C.V.: variation coefficient.

Silva et al. (2014) tested the in vitro antagonist potential of Trichodermalongibrachiatum, T. harzianum and T. viride on Fusarium solani isolates and obtained expressive results. All Trichoderma species presented significant antagonistic effect against F. solani isolates, in which control obtained an exceptionally larger mycelial growth value when compared to those obtained by cultures in the presence of the antagonist agent. This result corroborates those obtained in the studies performed by Bomfim et al. (2010), who tested the in vitro antagonism of T. viride, T. harzianum, T. stromaticum and T. virens against Rhizopus stolonifer isolates, where T. viride had greater inhibition of the pathogen growth, while T. stromaticum and T. virens had lower inhibition potential when compared to the other species. Nevertheless, all biocontrol agents differed from control. These reports demonstrated the efficiency of Trichoderma spp. as a biological control for several phytopathogens.

3.3. The action of Trichoderma spp. volatile metabolites on Cladosporium spp. species

Regarding the production of volatile metabolites, all compounds based on Trichoderma spp. were efficient, at least for some of the different Cladosporium spp. species tested (Figure 3).

Figure 3
Volatile metabolites test using formulations isolated from Trichoderma spp. on different Cladosporium spp. isolates Where: Letters correspond to the different treatments used. “A”: 6SC x Biotrich®; “B”: 6SC x T4UFSM; “C”: 6SC x Ecotrich®; “D”: 6SC; “E”: 12 / 7PR x Biotrich®; “F”: 12 / 7PR x T4UFSM; “G”: 12 / 7PR x Ecotrich®; “H”: 12 / 7PR; “I”: 16 / 2RS x Biotrich®; “J”: 16 / 2RS x T4UFSM; “K”: 16 / 2RS x Ecotrich®; “L”: 16 / 2RS.

Commercial product Biotrich® and T4UFSM isolate showed the best results for the inhibition of the mycelial growth of C. pseudocladosporioides species (6SC); in addition, Ecotrich^® also differed statistically from control. All compounds for the C. cladosporioides species (12/7PR) showed to be efficient; moreover, the species showed smaller mycelial growth when compared to the other species, while only T4UFSM isolate inhibited the mycelial growth of C. subuliforme (16/2RS), since the other products did not significantly differ from control, showing to be ineffective in this case (Table 5).

Table 5
In vitro mycelial growth (mm) of Cladosporium spp. in the volatile metabolites test produced by Trichoderma spp.

Cladosporium spp.	Trichoderma spp.
	Biotrich®	Ecotrich®	T4UFSM	Test.
6SC	41.89 aC*	47.87 aB	41.46 aC	59.95 aA
12/7PR	28.56 bB	28.69 bB	28.63 bB	35.42 cA
16/2RS	44.63 aBC	49.28 aA	40.61 aC	48.83 bAB
C.V.	5.62

• (*) means followed by the same lower-case letter in vertical lines and upper-case letters in horizontal lines do not differ from each other by the Tukey test at 5% error probability; C.V.: variation coefficient.

Using similar methodology, Gomes et al. (2001) obtained reduction in the mycelial growth of Cylindrocladiumspathulatum, which is responsible for the leaf spot in yerba mate (Ilex paraguariensis St. Hil), through volatile metabolites released by Trichoderma spp. The compounds released by the antagonist were also efficient when tested on Sclerotiniasclerotiorum isolates, considerably reducing its mycelial growth (Dildey et al., 2014). In addition, the results obtained in the present study corroborate those found by Dennis & Webster (1971), who reported that Trichoderma species is effective in the production of volatile gases capable of inhibiting the growth of several microorganisms in culture medium.

4. CONCLUSIONS

Trichoderma spp. is efficient in the in vitro control of Cladosporium pseudocladosporioides, C. cladosporioides and C. subuliforme species. In addition, there is reduction in the mycelial growth of pathogens through the production of volatile compounds produced by Trichoderma spp. biocontrol agent. Thus, Trichoderma spp. presents potential to be used in the control of pathogens causing leaf spots in pecan trees (Caryaillinoinensis).

REFERENCES

• Bataszkowski J, Adamska I, Czerniawska B, Madej T, Zioto E. Saprotrophic, pathogenic and symbiotic fungi of poland [online]. 2005 [cited 2017 Jan 28]. Available from: http://www.zor.zut.edu.pl/Mycota/index.html
  » http://www.zor.zut.edu.pl/Mycota/index.html
• Bell DK, Wells HD, Markham CR. In vitro antagonism if Trichoderma species against six fungal plant pathogens. Ecology and Epidemiology 1982; 72(4): 379-382.
• Benítez T, Rincón AM, Limón MC, Codón AC. Biocontrol mechanisms of Trichoderma strains. International Microbiology 2004; 7(4): 249-260. PMid:15666245.
• Bensch K, Groenewald JZ, Dijksterhuis J, Starink-Willemse M, Andersen B, Summerell BA et al. Species and ecological diversity within the Cladosporium cladosporioides complex (Davidiellaceae, Capnodiales). Studies in Mycology 2010; 67: 1-94. http://dx.doi.org/10.3114/sim.2010.67.01 PMid:20877444.
  » http://dx.doi.org/10.3114/sim.2010.67.01
• Bomfim MP, São José AR, Rebouças TNH, Almeida SS, Souza IVB, Dias NO. Avaliação antagônica in vitro e in vivo de Trichoderma spp. a Rhizopus stolonifer em maracujazeiro amarelo. Summa Phytopathologica 2010; 36(1): 61-67. http://dx.doi.org/10.1590/S0100-54052010000100011
  » http://dx.doi.org/10.1590/S0100-54052010000100011
• Castellani A. Viability of some pathogenic fungi in distilled water. The Journal of Tropical Medicine and Hygiene 1939; 42: 225-226.
• Dennis C, Webster J. Antagonistic properties of species-groups of Trichoderma. III. Hyphal interactions. Transactions of the British Mycological Society 1971; 57(3): 363-369. http://dx.doi.org/10.1016/S0007-1536(71)80050-5
  » http://dx.doi.org/10.1016/S0007-1536(71)80050-5
• Dhingra OD, Sinclair JB. Basic plant pathology methods 2nd ed. USA: CRC Press Book; 1995.
• Dias PP, Berbara RLL, Fernandes MCA. Controle de Rhizoctonia solanie Fusarium oxysporumf.sp. phaseoli por biopreparados de isolados de Trichoderma spp. Summa Phytopathologica 2013; 39(4): 258-262. http://dx.doi.org/10.1590/S0100-54052013000400005
  » http://dx.doi.org/10.1590/S0100-54052013000400005
• Dildey ODF, Barbian JM, Gonçalves EDV, Broetto L, Ethur LZ, Kuhn OJ et al. Inibição do crescimento in vitro de Sclerotinia sclerotiorum, causador de mofo branco, por isolados de Trichoderma spp. Revista Brasileira de Biociências 2014; 12(3): 132-136.
• Durigon MR, Blume E, Muniz MFB, Milanesi PM, Santos RF, Heckler LI et al. Adubações orgânicas e mineral e controle biológico sobre a incidência de podridões de colmo e produtividade de milho. Semina: Ciências Agrárias 2014; 35(3): 1249-1256. http://dx.doi.org/10.5433/1679-0359.2014v35n3p1249
  » http://dx.doi.org/10.5433/1679-0359.2014v35n3p1249
• Ethur LZ. Dinâmica populacional e ação de Trichoderma no controle de Fusariose em mudas de tomateiro e pepineiro [tese]. Santa Maria: Setor de Produção Vegetal, Universidade Federal de Santa Maria; 2006.
• Ferreira DF. Estatística básica 2. ed. Lavras: UFLA; 2009.
• Gomes NSB, Grigoletti AJ, Auer CG. Seleção de antagonistas para o controle de Cylindrocladium spathulatum em erva-mate. Boletim de Pesquisa Florestal 2001; 43: 123-138.
• Howell CR. Mechanisms employed by Trichoderma species in biological control of plant diseases: the history and evolution of current concepts. Plant Disease 2003; 87(1): 4-10. http://dx.doi.org/10.1094/PDIS.2003.87.1.4 PMid:30812698.
  » http://dx.doi.org/10.1094/PDIS.2003.87.1.4
• Jeyaseelan ER, Tharmila S, Niranjan K. Antagonistic activity of Trichoderma spp. and Bacillus spp. against Pythium aphanidermatum isolated from tomato damping off. Archives of Applied Science Research 2012; 4(4): 1623-1627.
• Machado DFM, Silva ACF. Trichoderma no controlo in vitro de fungos presentes em diásporos de Gochnatiapolymorpha. Ciências Agrárias 2013; 36(2): 182-191.
• Maciel CG, Lazarotto M, Mezzomo R, Poletto I, Muniz MFB, Lippert DB. Trichoderma spp no biocontrole de Cylindrocladium candelabrum em mudas de Eucalyptus saligna Revista Árvore 2012; 36(5): 825-832. http://dx.doi.org/10.1590/S0100-67622012000500004
  » http://dx.doi.org/10.1590/S0100-67622012000500004
• Ortiz ERN, Camargo LEA. Doenças da Nogueira Pecan. In: Kimati H, Amorim L, Bergamin AF, Camargo LEA, Rezende JAM, editores. Manual de fitopatologia: doenças das plantas cultivadas São Paulo: Agronômica Ceres; 2005.
• Pereira RTG, Pfenning LH, de Castro HA. Caracterização e dinâmica de colonização de Cladosporium cladosporioides (Fresen.) de vries em frutos do cafeeiro (Coffea arábica L.). Ciência e Agrotecnologia 2005; 29(6): 1112-1116. http://dx.doi.org/10.1590/S1413-70542005000600002
  » http://dx.doi.org/10.1590/S1413-70542005000600002
• Ribeiro TS. O fungo Trichoderma spp. no controle de fitopatógenos: dificuldades e perspectivas [monografia]. Porto Alegre: Pós-graduação Latu Sensu “Tecnologias Inovadoras no Manejo Integrado de Pragas e Doenças de Plantas, Universidade Federal do Rio Grande do Sul; 2009.
• Silva AN, Azevedo GB, Sobrinho GGR, Novaes QS. Efeito de produtos químicos e de Trichoderma spp. no controle de Fusariumsolani do maracujazeiro. Interciencia 2014; 39(6): 398-402.
• Silva KS, Rebouças HN, Bomfim MP, Silva DS, São José AR, Benett CGS. Atividade antagônica in vitro de isolados de Trichoderma spp. ao fungo Phytophthora citrophthora. Semina: Ciências Agrárias 2008; 24(4): 749-754. http://dx.doi.org/10.5433/1679-0359.2008v29n4p749
  » http://dx.doi.org/10.5433/1679-0359.2008v29n4p749
• Vega JA, Aceves ACM, Márquez VMD, Eméstica OAS. Antagonismo de Trichoderma spp. sobre Mycosphaerella fijiensis Morelet, Agente Causal de la Sigatoka Negra del Plátano (Musa sp.) in vitro e Invernadero. Revista Mexicana de Fitopatología 2006; 24(2): 98-104.
• Walker C, Muniz MFB, Martins RRO, Mezzomo R, Rolim JM, Blume E. First reporto of species in the Cladosporium cladosporioides complex causing pecan leaf spot in Brazil. Journal of Plant Pathology 2016a; 98(12)
• Walker C, Muniz MFB, Rolim JM, Martins RRO, Rosenthal VC, Maciel CG et al. Morphological and molecular characterization of Cladosporium cladosporioides species complex causing pecan tree leaf spot. Genetics and Molecular Research 2016b; 15(3). http://dx.doi.org/10.4238/gmr.15038714 PMid:27706736.
  » http://dx.doi.org/10.4238/gmr.15038714

Publication Dates

• Publication in this collection
  2 May 2019
• Date of issue
  2019

History

• Received
  10 May 2017
• Accepted
  19 Feb 2018