R-03 A POSSIBILITY OF USING GRAPEFRUIT EXTRACT, CHITOSAN AND PYTHIUM OLIGANDRUM TO PROTECT SOYBEAN (GLYCINE MAX (L.) MERRILL) FROM PATHOGENS



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R-03 A POSSIBILITY OF USING GRAPEFRUIT EXTRACT, CHITOSAN AND PYTHIUM OLIGANDRUM TO PROTECT SOYBEAN (GLYCINE MAX (L.) MERRILL) FROM PATHOGENS Danuta Pięta, Alina Pastucha, Elżbieta Patkowska Department of Plant Pathology, University of Agriculture in Lublin, ul. Kr. Leszczyńskiego 7, 20-069 Lublin, Poland e-mail: danuta.pieta@ar.lublin.pl 1. Introduction For twenty years intensive studies on searching for new methods of biological control of plant diseases have been conducted. One of such methods is the use of biopreparations. Nowadays in Poland Biosept 33 SL (grapefruit extract), Biochikol 020 PC (chitosan) and Polyversum (oospores of Pythium oligandrum) are registered. Abundant information from literature report that biopreparations on the basis of both organic compounds and antagonistic microorganisms inhibit the occurrence of different plant diseases [1-8]. 2. Materials and methods The object of studies in the years 2005-2006 were the seedlings and plants of soybean at anthesis which grew from the seeds dressed with 0.2% Biosept 33 SL, 2.5% Biochikol 020 PC and Polyversum in a dose of 1 g of the preparation 1 kg -1 seeds. At the beginning of anthesis the plants were sprayed with the same biopreparations that had been used for seed dressing. The experiment considered the combination with a chemical preparation Zaprawa Oxafun T for seed dressing, and Bravo Plus 500 SC for spraying plants at anthesis. Plants without any protective treatment constituted the control. During the vegetation period the studies established the population and healthiness of plants in particular phases of development, i.e. in the phase of 6-week-old seedlings and plant at full anthesis 7 days after the spraying. The diseased plants were taken for laboratory mycological analysis, which was carried out according to the method described by Pięta [9]. After the harvest the yield weight and the proportion of spotted seeds were determined in particular experimental combinations. The rhizosphere soil was also the object of studies. Sampling the rhizosphere soil and its microbiological analysis were according to the method described by Patkowska et al. [10] and Martyniuk [11]. In order to obtain the total number cfu of bacteria in the rhizosphere soil of soybean, Polish Chitin Society, Monograph XII, 2007 197

D. Pięta, A. Pastucha, E. Patkowska PDA medium was used with an addition of yeast extract and dilutions of soil solution 10-5, 10-6, 10-7. Tryptic Soy Agar and dilutions 10-4, 10-5, 10-6 were used to isolate Bacillus spp., whereas medium Pseudomonas Agar F and water dilutions of the soil solution 10-2, 10-3 and 10-4 were used for Pseudomonas spp. Martin medium [12] and the dilutions 10-2, 10-3 and 10-4 were used to calculate the total number cfu of fungi occurring in the rhizosphere soil. The results were statistically analyzed and the significance of differences was determined on the basis of Duncan s [13] confidence semi-intervals. 3. Results and discussion It was found out on the basis of the obtained results of the observations both in the phase of seedlings and at full anthesis that the number and healthiness of plants were the best in the combination with Biosept 33 SL (Table 1). A lot of plants were in the plots with the combinations with biopreparations (Polyversum, Biochikol 020 PC) and with chemical preparations (Zaprawa Oxafun T + Bravo Plus 500 SC) (Figure 1). The smallest number of plants with the highest share of the diseased ones was found on control plots (Figure 1). The results of studies confirmed the information on the effectiveness of the tested biopreparations in controlling diseases in different plants [1-8]. The highest yield with the best quality seeds was obtained from the plants treated with Biosept 33 SL (Figure 2). A high yield was also obtained in the combination with Polyversum and Biochikol 020 PC and with chemical preparations. The lowest seed yield with a big proportion of seeds with spots was obtained from control plants (Figure 2). The greatest amount of Fusarium spp. (F. culmorum, F. oxysporum and F. solani) was obtained as a result of the mycological analysis (Table 1). The period of vegetation in the years Table 1. Fungi frequently isolated from soybean plants in individual experimental (sum from the years 2005-2006). Fungus species Polyversum Biochikol 020 PC Number of isolates Biosept 33 SL Zaprawa Oxafun T + Bravo Plus 500 SC Control Alternaria alternata 20 19 8 26 36 109 Botrytis cinerea 2 5 7 14 Fusarium spp. 76 81 70 136 189 552 Fusarium culmorum 13 11 15 23 27 89 Fusarium oxysporum 51 45 44 70 103 313 Fusarium solani 11 22 9 39 53 134 Gliocladium spp. 26 54 34 18 19 151 Phoma exigua 6 17 7 22 31 83 Pythium irregulare 4 6 4 15 22 51 Rhizoctonia solani 9 7 21 29 66 Sclerotinia sclerotiorum 2 1 6 9 18 Trichoderma spp. 29 70 31 14 16 160 Total 249 333 222 395 541 1740 Total 198 Polish Chitin Society, Monograph XII, 2007

A possibility of using grapefruit extract, chitosan and Pythium oligandrum to protect soybean... Figure 1. Number and healthiness of soybean plants on plots (mean from the years 2005-2006); Polyv. - Polyversum, Bioch. - Biochikol 020 PC, Bios. - Biosept 33 SL, Z.Ox.T - Zaprawa Oxafun T, Br. - Bravo Plus 500 SC. Figure 2. Yield and participation of infected soybean seeds (mean from the years 2005-2006); Polyv. - Polyversum, Bioch. - Biochikol 020 PC, Bios. - Biosept 33 SL, Z.Ox.T - Zaprawa Oxafun T, Br. - Bravo Plus 500 SC. 2005-2006 was favorable for the development of Fusarium spp. and plant infection (characterized by high air temperature). According to Booth [14], Sinclair and Backman [15], these are the fungi that require temperature between 22 and 28 C for their growth. Besides, Alternaria alternata, Botrytis cinerea, Phoma exigua, Rhizoctonia solani, Pythium irregulare were isolated from the studied plants as well as Sclerotinia sclerotiorum from plants at anthesis (Table 1). Saprobionts such as Gliocladium spp. and Trichoderma spp. were also obtained in big numbers (Table 1). According to Dos Santos and Dhingra [16], the number of Fusarium spp. colonies considerably drops with abundant occurrence of Trichoderma Polish Chitin Society, Monograph XII, 2007 199

D. Pięta, A. Pastucha, E. Patkowska spp. Antagonistic Gliocladium spp. and Trichoderma spp., colonizing the rhizosphere of soybean, can constitute a protective barrier against pathogens [17, 18]. Results of the studies pointed to a positive effect of biopreparations on the increase of cfu total bacteria, Bacillus spp. and Pseudomonas spp. (Figure 3). In each year of the studies the greatest number of cfu total bacteria occurred in the rhizosphere soil of soybean after using biopreparation Biosept 33 SL, while the smallest amount was found in the control soil (Figure 3). The number cfu of Pseudomonas spp. was also the highest in the rhizosphere soil of soybean treated with Biosept 33 SL. On the other hand, the most cfu Bacillus spp. was found in the rhizosphere soil after using Biochikol 020 PC, and the smallest amount in the rhizosphere soil of the control, i.e. without any protective treatment. The number of cfu fungi in the studied samples of soil was reverse to the number of bacteria. The most fungi colonies were isolated from the control soil, and the fewest from the soil after using biopreparations (Figure 4). According to the studies conducted by Myśków [19], definite proportions occur between microorganisms. When the bacteria are numerous, the development of fungi is weakened and vice versa. Gliocladium spp. and Trichoderma spp., as antagonistic fungi, were most abundant in the rhizosphere soil of soybean after the application of Biochikol 020 PC and Biosept 33 SL (Figure 5). Chitosan is a compound which stimulates the growth and development of antagonistic microorganisms, especially Trichoderma spp. [20]. A lot of such antagonists were found in the rhizosphere soil after the application of Polyversum, and sporadically they were found in the control soil after using chemical preparations. Similarly, antagonistic Bacillus Figure 3. Number cfu bacteria (in mln g-1d.w. soil) isolated from rhizosphere of soybean (mean from the years 2005-2006); Polyv. - Polyversum, Bioch. - Biochikol 020 PC, Bios. - Biosept 33 SL, Z.Ox.T - Zaprawa Oxafun T, Br. - Bravo Plus 500 SC. 200 Polish Chitin Society, Monograph XII, 2007

A possibility of using grapefruit extract, chitosan and Pythium oligandrum to protect soybean... Figure 4. Number cfu fungi (in thous. g-1d.w. soil) isolated from rhizosphere of soybean (mean from the years 2005-2006); Polyv. - Polyversum, Bioch. - Biochikol 020 PC, Bios. - Biosept 33 SL, Z.Ox.T - Zaprawa Oxafun T, Br. - Bravo Plus 500 SC. Figure 5. Number of antagonistic microorganisms (sum from the years 2005-2006); Polyv. - Polyversum, Bioch. - Biochikol 020 PC, Bios. - Biosept 33 SL, Z.Ox.T - Zaprawa Oxafun T, Br. - Bravo Plus 500 SC. Polish Chitin Society, Monograph XII, 2007 201

D. Pięta, A. Pastucha, E. Patkowska spp. and Pseudomonas spp. occurred in the studied soil samples (Figure 5). It should be expected that abundant occurrence of antagonists can reduce the growth and development of phytopathogens. This fact is confirmed by a lot of information in literature [3-5, 21-24]. According to Allan and Hadwiger [25], chitosan and grapefruit extract affect pathogenic fungi like a fungicide. In the case of Polyversum, antagonistic fungus Pythium oligandrum, which limits the occurrence of pathogenic fungi through competition, superparasitism and antibiosis, is the active factor [21, 26]. Hence, it should be supposed that the, use of biopreparations not only reduces the occurrence of phytopathogens in the soil but it also protects the plants from pathogenic fungi. A big proportion of antagonists in the soil keeps the balance between the populations of microorganisms and stops the excessive development of pathogenic fungi, by which the soil becomes suppressive. 4. References 1. Borkowski J., Nowosielski O.: The use of Trichodex 25 WP, Biosept 33 SL, Chitosan and Florochron in the protection of tomato against powdery mildew. The effect of these preparations on the fruit yield. Bull. Pol. Acad. Sci. biol. Sci. 49 (3), 2001, 173 178. 2. Borkowski J., Felczyńska A., Stepowski J.:. Effect of different compounds Biochikol 020 PC, calcium nitrate, Tytanit and Pomonit on the healthiness and the yield of chinese cabbage. Polish Chitin Soc., Monograph XI, 2006, 201 207. 3. Orlikowski L. B., Skrzypczak Cz., Wojdyła A.: Biological activity of plant extracts and chitosan toward soil-borne and leaf pathogens. Botanica Lithuanica 3, 1999, 147 154. 4. Orlikowski L. B., Skrzypczak Cz., Harmaj I.: Biological activity of grapefruit extract in the control of Fusarium oxysporum. J. Plant Prot. Res. 41, 4, 2001a, 420 427. 5. Orlikowski L. B., Skrzypczak Cz., Jaworska-Marosz A.: Influence of grapefruit extract on the growth and development of Botrytis spp. and grey mould of lily and peony. Bull. Pol. Acad. Sci., Biol. Sci. 49, 4, 2001b, 373 378. 6. Pospieszny H., Struszczyk H.: Chitozan-potencjalny biopreparat przeciwko patogenom roślin. Mat. 34 Sesji Nauk. IOR, 1994, 117 123. 7. Szczeponek A., Mazur S., Nawrocki J.: The usage of chitosan in protection of some peppermint and lemon balm pathogens. Polish Chitin Soc., Monograph XI, 2006, 103 200. 8. Wojdyła A. T., Orlikowski L. B., Niekraszewicz A., Struszczyk H.: Chitosan in the control of Sphaerotheca pannosa var. rosea and Peronospora sparsa on roses and Myrothecium roridum on diffenbachia. VII Conf. 18-19 March, sec. Biol. Control Plant Dis. Polish Phytopath. Soc. 151, 1997, Skierniewice. 9. Pięta D.: Mikozy występujace w uprawach fasoli (Phaseolus vulgaris L.) i podatności różnych odmian na porażenie przez niektóre grzyby. Wyd. AR Lublin, ser. Rozpr. Nauk., 111, 1988, 1 77. 10. Patkowska E.: 2006. The use of bioreparations in the control of soybean endangered by pathogenic soil-borne fungi. EJPAU, Horticulture, Vol. 9, Issue 1, http://www.ejpau.media.pl/ volume9/issue1/art.-19.html 11. Martyniuk S., Masiak D., Stachyra A., Myśków W.: Populacje drobnoustrojów strefy korzeniowej różnych traw i ich antagonizm w stosunku do Gaeumannomyces graminis var. tritici. Pam. Puł. Pr. IUNG 98, 1991, 139 144. 12. Martin J. P.: Use of acid, rose bengal and streptomycin in the plate method for estimating soil fungi. Soil Sci. 38, 1950, 215 220. 13. Elandt R.:. Statystyka matematyczna w zastosowaniu do doświadczalnictwa rolniczego. Warszawa PWN, 1964. 14. Booth G.:. The genus Fusarium. Mycol. Papers CMY, England, 1971. 15. Sinclair J. B., Backman P. A.: Compedium of soybean diseases. Amer. Phytopathol. Soc., PRESS, USA, 1989, 106 pp. 202 Polish Chitin Society, Monograph XII, 2007

A possibility of using grapefruit extract, chitosan and Pythium oligandrum to protect soybean... 16. Dos Santos A.F., Dhingra O.D.: Pathogenicity of Trichoderma spp. on the sclerotia of Sclerotinia sclerotiorum. Can. J. Bot., 60, 1982, 472. 17. Papavizas G.C.: Gliocladium i Trichoderma : Biology, ecology and potential for biocontrol. Ann. Rev. Phytopathol. 23, 1985, 23 54. 18. Weller D.M.:. Biological control of soilborne plant pathogens in the rhizospere with bacteria. Ann. Rev. Phytopathol. 26, 1988, 379 407. 19. Myśków W.: Związek między aktywnością biologiczną gleby a jej żyznością i urodzajnością. Biologiczne metody podnoszenia żyzności i urodzajności gleb. Mat. Szkol., Puławy, 1989, 51 53. 20. Patkowska E., Pięta D., Pastucha A.: The effect of Biochikol 020 PC on microorganism communities in the rhizosphere of Fabaceae plants. Polish Chitin Soc. Monograph XI, 2006, 171-178. 21. Martin F. N., Hancock J. G.: The use of Pythium oligandrum for biological control of preemergence damping-off caused by P. ultimum. Phytopathology 77, 1987, 1013 1020. 22. Orlikowski L. B., Skrzypczak Cz., Wojdyła A., Jaworska-Marosz A.:. Wyciągi roślinne i mikroorganizmy w ochronie roślin przed chorobami. Zesz. Nauk. AR w Krakowie 387(82), 2002, 19 32. 23. Gajda I., Kurzawińska H.: Effect Polyversum and Fungazil 100 SL on the growth of Helminthosporium solani. Phytopathol. Pol. 32, 2004a, 75 81. 24. Gajda I., Kurzawińska H.:. Potential use of Pythium oligandrum and imazalil in the protection of potato against Rhizoctonia solani. Phytopathol. Pol. 33, 2004b, 47 52. 25. Allan C. R., Hadwiger L. A.:. The fungicidal effect of chitosan on fungi of varying cell wall composition. Exp. Mycol. 3, 1979, 285 287. 26. Vesely D., Kocova L.: Pythium oligandrum as the biological control agent the praparation of Polyversum. Bull. Pol. Acad. Sci., Biol. Sci. 49, 3, 2001, 209 218. Acknowledgment This research work was financial supported by the Ministry of Science and Information within the research project No 3P06 034 25. Polish Chitin Society, Monograph XII, 2007 203