MASTER OF SCIENCE (AGRICULTURE) in PLANT PATHOLOGY

Transcription

1 EVALUATION OF CONTACT AND SYSTEMIC FUNGICIDES OF VARIOUS FIRMS FOR THEIR EFFICIENCY AGAINST WILT PATHOGEN OF CHICKPEA AND LEAF SPOT PATHOGEN OF TOMATO AND ONION By Miss Subu Sunya A thesis submitted to the (Reg. No. 011/244) MAHATMA PHULE KRISHI VIDYAPEETH, RAHURI , DIST. AHMEDNAGAR, MAHARASHTRA (INDIA) In partial fulfillment of the requirements for the degree of MASTER OF SCIENCE (AGRICULTURE) in PLANT PATHOLOGY APPROVED BY Dr. S.G Borkar (Chairman and Research Guide) Dr. B.G Barhate (Committee Member) Dr. A.M Navale (Committee Member) Dr. R.W Bharud (Committee Member) DEPARTMENT OF PLANT PATHOLOGY AND AGRICULTURAL MICROBIOLOGY POST GARDUATE INSTITUTE, MAHATMA PHULE KRISHI VIDYAPEETH, RAHURI , DIST. AHMEDNAGAR MAHARASHTRA (INDIA) 2013

2 ii CANDIDATE S DECLARATION I hereby declare that this thesis or a part thereof has not been submitted by me or any other person to any other University or Institute for a Degree or Diploma. Place: M.P.K.V., Rahuri Date: / / 2013 ( Subu Sunya )

3 iii Dr. S.G Borkar Associate Dean, Post Graduate Institute, Mahatma Phule Krishi Vidyapeeth, Rahuri , Dist. Ahmednagar, Maharashtra State (INDIA) C E R T I F I C A T E This is to certify that the thesis entitled, EVALUATION OF CONTACT AND SYSTEMIC FUNGICIDES OF VARIOUS FIRMS FOR THEIR EFFICIENCY AGAINST WILT PATHOGEN OF CHICKPEA AND LEAF SPOT PATHOGEN OF TOMATO AND ONION, submitted to the Faculty of Agriculture, Mahatma Phule Krishi Vidyapeeth, Rahuri, Dist. Ahmednagar, Maharashtra (India), in partial fulfilment of the requirements for the degree of MASTER OF SCIENCE (AGRICULTURE) in PLANT PATHOLOGY AND AGRICULTURAL MICROBIOLOGY, embodies the results of piece of bona fide research work carried out by Miss Subu Sunya, under my guidance and supervision and that no part of the thesis has been submitted to any other University for degree or diploma. The assistance and help received during the course of this investigation and sources of reference have been duly acknowledged. Place : M.P.KV., Rahuri (Dr. S.G Borkar) Date : / /2013 Research Guide

4 iv Dr. S.G. Borkar Associate Dean, Post Graduate Institute, Mahatma Phule Krishi Vidyapeeth, Rahuri , Dist. Ahmednagar, Maharashtra (INDIA) CERTIFICATE This is to certify that the thesis entitled, EVALUATION OF CONTACT AND SYSTEMIC FUNGICIDES OF VARIOUS FIRMS FOR THEIR EFFICIENCY AGAINST WILT PATHOGEN OF CHICKPEA AND LEAF SPOT PATHOGEN OF TOMATO AND ONION, submitted to the Faculty of Agriculture, Mahatma Phule Krishi Vidyapeeth, Rahuri, Dist. Ahmednagar, Maharashtra in partial fulfilment of the requirements for the degree of MASTER OF SCIENCE (AGRICULTURE) in PLANT PATHOLOGY AND AGRICULTURAL MICROBIOLOGY, embodies the results of a piece of bona fide research work carried out by Miss Subu Sunya, under the guidance and supervision of Dr. S.G Borkar, Associate Dean, Post Graduate Institute, Mahatma Phule Krishi Vidyapeeth, Rahuri and that no part of the thesis has been submitted for any other Degree or Diploma. Place: M.P.K.V., Rahuri (Dr. S.G. Borkar) Date: / /2013 Associate Dean

5 v ACKNOWLEDGEMENT First and foremost I offer my sincerest gratitude to my Guide, Dr S.G Borkar, who has supported me throughout my thesis with his patience and knowledge whilst allowing me the room to work in my own way. I attribute the level of my Masters degree to his encouragement, for his excellent guidance, caring, patience, and providing me with an excellent atmosphere for doing research, for his continuous support, patience, motivation, enthusiasm, and immense knowledge and effort. Without him this thesis, would not have been completed or written. I could not have imagined having a better advisor, mentor, or friendlier guide for my MSc study and research. His guidance helped me in all the time of research and writing of this thesis. He had given me an unequivocal support throughout, as always, for which my mere expression of thanks likewise does not suffice. Besides my guide, I would like to thank the rest of my advisory committee members: Dr. B.G. Barhate, Assistant Professor, Department of Plant pathology and Agricultural Microbiology, M.P.K.V., Rahuri, Dr. A.M. Navale, Associate professors, Department of Plant Pathology and Agricultural Microbiology, M.P.K.V., Rahuri,and Dr. R.W. Bharud, Head, Department of Botany, M.P.K.V., Rahuri for their encouragement, insightful comments, and hard questions. Grateful thanks to Dr. B.R. Ulmek, Dean, Faculty of Agriculture, M.P.K.V., Rahuri for giving permission and providing necessary facilities for the research work. I extent my great regards to Dr. C.A. Nimbalkar, Associate Professor, Department of Statistics, Dr. B.M. Ilhe, Associate Professor, Department of Plant pathology and Agricultural Microbiology, Dr. K.S. Raghuwanshi, Associate professor, Department of Plant Pathology, M.P.K.V., Rahuri Dr. C.D. Deokar, Professor, Department of Plant Pathology and Agricultural Microbiology. I would like to take this opportunity to convey my sincere thanks to all other respected teachers and non-teaching staffs of the Department of Plant pathlogy and Agricultural Microbiology for their cooperation, generous assistance and valuable suggestions to me. I also record my deep sense of gratitude to Mr. P.A. Shinde, Librarian, M.P.K.V., Rahuri, Mr. R.N. Ingale and whole staff of University Library for their kindly help and unique co-operation during preparation of this manuscript. I thank my fellow batchmates in P.G.I M.P.KV Rahuri: Sofia, Joymati, Geetanjali Jayashree and Pratibha for their help and support, to only some of whom it is possible to give particular mention here, and for all the fun we have had in the last 2 years. I specially thank Sofia yanglem and Joymati chanu, they were always there cheering me up and stood by me through the good times and bad, they have been an unfailing source of encouragement during my low times.

6 vi Last, but by no means least, I would like to thank all my wonderful friends in P.G.I, M.P.K.V, Rahuri and elsewhere for their support and encouragement throughout: Rubina, Ruchali, Vandana, Preeti, Manjiri, Bhosle and Kaptan. In particular I would like to thank Gaikwad sir, who as a good senior was always willing to help and give his best suggestions when i needed it most. Many thanks to Bade Sir, Nitin sir, Suryawanshi sir, Ganesh bhaiya, Nagre mam and other workers in the laboratory of Department of Plant pathology for helping me in one way or other. Above all, I would like to thank my family: my parents Subu Sira and Subu Yaja, for giving birth to me at the first place and supporting me spiritually throughout my life, thank you so much Dear Lord. My parents have made countless sacrifices for me, and have provided me with steady guidance and encouragement. My special and sincere thanks to Mr. Vishwanath Kadam Suyog Computers for painstaking help and excellence in typing this manuscript and the authors whose references incited in this manuscript. For any errors or inadequacies that may remain in this work, of course, the responsibility is entirely my own. Place: M.P.K.V., Rahuri Date: / /2013 (Subu Sunya)

7 vii CONTENTS CANDIDATE S DECLARATION Ii CERTIFICATES 1. Research Guide 2. Associate Dean (PGI) ACKNOWLEDGEMENT LIST OF TABLES LIST OF PLATE LIST OF ABBREVIATIONS ABSTRACT iii iv V Viii Xii Xiii Xv INTRODUCTION 1 REVIEW OF LITERATURE 10 MATERIAL AND METHODS 25 RESULTS 36 DISCUSSION 83 SUMMARY AND CONCLUSIONS 104 LITERATURE CITED 114 VITA 127

8 viii LIST OF TABLES Sr. Title Page No. 1. Fungicides used for evaluation during study Invitro evaluation of Carbendazim of various firms against wilt pathogen Fusarium oxysporum infecting Chickpea 3. Invitro evaluation of Metalxyl+Mancozeb of various firms against wilt pathogen Fusarium oxysporum infecting Chickpea 4. Invitro evaluation of Copper oxychloride of various firms against wilt pathogen Fusarium oxysporum infecting Chickpea 5. Invitro evaluation of Copper oxychloride of various firms against leaf spot pathogen Alternaria porri infecting Onion 6. Invitro evaluation of Chlorothalonil of various firms against leaf spot pathogen Alternaria porri infecting Onion 7. Invitro evaluation of Mancozeb of various firms against leaf spot pathogen Alternaria porri infecting Onion 8. Invitro evaluation of Metalxyl+Mancozeb of various firms against leaf spot pathogen Alternaria porri infecting Onion 9. Invitro evaluation of Captan of various firms against leaf spot pathogen Alternaria porri infecting Onion

9 ix List of Table contd. Sr. Title No. 10. In vitro evaluation of Propiconazole of various firms against leaf spot pathogen Alternaria porri infecting Onion 11. In vitro evaluation of Hexaconazole of various firms against leaf spot pathogen Alternaria porri infecting Onion 12. In vitro evaluation of Copper oxychloride of various firms against leaf spot pathogen Alternaria alternata infecting Tomato 13. In vitro evaluation of Chlorothalonil of various firms against leaf spot pathogen Alternaria alternata infecting Tomato 14. In vitro evaluation of Mancozeb of various firms against leaf spot pathogen Alternaria alternata infecting Tomato 15. In vitro evaluation of Metalxyl+Mancozeb of various firms against leaf spot pathogen Alternaria alternata infecting Tomato 16. In vitro evaluation of Captan of various firms against leaf spot pathogen Alternaria alternata infecting Tomato 17. In vitro evaluation of Propiconazole of various firms against leaf spot pathogen Alternaria alternata infecting Tomato 18. In vitro evaluation of Hexaconazole of various firms against leaf spot pathogen Alternaria alternata infecting Tomato 19. In vitro evaluation of Metalxyl+Mancozeb of various firms as seed treatment against seed borne pathogen on chickpea seeds Page

10 x List of Table contd. Sr. Title No. 20. In vitro evaluation of Carbendazim of various firms as seed treatment against seed borne pathogen on chickpea seeds 21. In vitro evaluation of Captan of various firms as seed treatment against seed borne pathogen on chickpea seeds 22. In vivo evaluation of Carbendazim as seed treatment against wilt pathogen Fusarium oxysporum in chickpea 23. In vivo evaluation of Captan as seed treatment against wilt pathogen Fusarium oxysporum in chickpea 24. In vivo evaluation of Metalxyl+Mancozeb as seed treatment against wilt pathogen Fusarium oxysporum in chickpea 25. In vivo evaluation of Copper oxychloride as foliar spray on incidence and intensity of Alternaria leaf blight of Onion 26. In vivo evaluation of Chlorothalonil as foliar spray on incidence and intensity of Alternaria leaf blight of Onion 27. In vivo evaluation of Mancozeb as foliar spray on incidence and intensity of Alternaria leaf blight of Onion 28. In vivo evaluation of Metalxyl+Mancozeb as foliar spray on incidence and intensity of Alternaria leaf blight of Onion 29. In vivo evaluation of Hexaconazole as foliar spray on incidence and intensity of Alternaria leaf blight of Onion Page

11 xi List of Table contd. Sr. No. Title 30. In vivo evaluation of Captan as foliar spray on incidence and intensity of Alternaria leaf blight of Onion 31. In vivo evaluation of Propiconazole as foliar spray on incidence and intensity of Alternaria leaf blight of Onion 32. In vivo evaluation of Copper oxychloride as foliar spray on incidence and intensity of Alternaria leaf spot of Tomato 33. In vivo evaluation of Chlorothalonil as foliar spray on incidence and intensity of Alternaria leaf spot of Tomato 34. In vivo evaluation of Mancozeb as foliar spray on incidence and intensity of Alternaria leaf spot of Tomato 35. In vivo evaluation of Metalxyl+Mancozeb as foliar spray on incidence and intensity of Alternaria leaf spot of Tomato 36. In vivo evaluation of Hexaconazole as foliar spray on incidence and intensity of Alternaria leaf spot of Tomato 37. In vivo evaluation of Captan as foliar spray on incidence and intensity of Alternaria leaf spot of Tomato 38. In vivo evaluation of Propiconazole as foliar spray on incidence and intensity of Alternaria leaf spot of Tomato Page

12 xii LIST OF PLATES Sr. No. Title 1. In vitro evaluation of fungicides against wilt pathogen of Chickpea Between pages a. 2b. 3a. 3b. In vitro evaluation of fungicides against leaf blight pathogen of Onion In vitro evaluation of fungicides against leaf blight pathogen of Onion In vitro evaluation of fungicides against leaf spot of Tomato In vitro evaluation of fungicides against leaf spot of Tomato In vivo evaluation of fungicides against wilt pathogen of Chickpea a. 5b. 6a. 6b. In vivo evaluation of fungicides against leaf blight pathogen of Onion In vivo evaluation of fungicides against leaf blight pathogen of Onion In vivo evaluation of fungicides against leaf spot of Tomato In vivo evaluation of fungicides against leaf spot of Tomato

13 xiii LIST OF ABBREVIATIONS % : Per cent µm : Micrometer / : : At the rate of BOD : Biological oxygen demand 0C : Degree Celsius C.D. : Critical Differences cm : Centimeter C.R.D : Completely Randomized Design cv. : Cultivar EC : Emulsifiable concentrates et al. : Et alli etc. : Et cetra FYM : Farm Yard Manure Fig : Figure F.Sp : Forma species g : Gram ha : Hectare hrs. : Hours i.e. : Idest (That is) IFC : Inhibition of Fungal Colony kg : Kilogram (s) Lbs : Pounds Ltd. : Limited lit. : Litter mm : Millimeter ml : Milliliter No. : Number PDA : Potato dextrose agar PDI : Percent Disease Index

14 xiv ppm S.E. spp. UPL viz., WP : Part per millions : Standard error : Species : United Phosphorous Limited : Videlicent (Namely) : Wettable powder

15 xv ABSTRACT EVALUATION OF CONTACT AND SYSTEMIC FUNGICIDES OF VARIOUS FIRMS FOR THEIR EFFICIENCY AGAINST WILT PATHOGEN OF CHICKPEA AND LEAF SPOT PATHOGEN OF TOMATO AND ONION By SUBU SUNYA A candidate for the degree of MASTER OF SCIENCE (AGRICULTURE) in Plant Pathology and Agricultural Microbiology 2013 Research Guide : Dr. S.G BORKAR Department : Plant Pathology and Agricultural Microbiology Fungicides play an important role in the management of fungal plant pathogen and diseases caused by them. Fungicides are recommended as per their technical name; however several companies are known to manufacture the same fungicide. Whether the efficiency of the same technical fungicide manufactured by different firms are same or not, is not yet studied and known. Therefore an investigation was undertaken as Evaluation of contact and systemic fungicides of various firms for their efficacy against wilt pathogen of chickpea, and leaf spot pathogen of tomato and onion, under our laboratories in the Department of Plant Pathology and Agricultural Microbiology, and in vivo experiments were carried out in glass house, Post Graduate Institute during

16 xvi Abstract contd... Miss. Subu Sunya Among the fungicides Carbendazim, Metalxyl+Mancozeb and Copper oxychloride tested against the Fusarium oxysporum, a chickpea wilt pathogen (in vitro), the fungicide Carbendazim and Copper oxychloride was most effective. The fungicide Carbendazim was effective at % concentration whereas the fungicide Copper oxychloride was effective at 0.1 % concentration. Further the fungicide Copper oxychloride of Indofil was more effective than the fungicide of Zuari and Rallis company. The fungicide Carbendazim of all the three companies viz., Dhanuka, Zuari and BASF was equally effective against the chickpea wilt pathogen. Among the various chemicals viz., Copper oxychloride, Chlorothalonil, Mancozeb, Metalxyl+Mancozeb, Captan, Propiconazole and Hexaconazole evaluated against the Alternaria porri fungus, the fungicide Propiconazole and Hexaconazole was most effective as they have 100 % inhibition of fungal colonies under in vitro. Among the various chemicals viz., Copper oxychloride, Chlorothalonil, Mancozeb, Metalxyl+Mancozeb, Captan, Propiconazole and Hexaconazole evaluated for the control of Alternaria alternata fungus, the fungicide Propiconazole and Hexaconazole was most effective as they have 100 % inhibition of fungal colonies under in vitro test. Among the various chemicals viz., Metalxyl+Mancozeb, Carbendazim and Captan evaluated as seed dressing fungicide for Chickpea seeds to control seed borne pathogen (in vitro), Carbendazim at 2 % of all the three companies was found most

17 xvii Abstract contd... Miss Subu Sunya effective followed by Metalxyl+Mancozeb of Syngenta Company and Captan of Zuari and Rallis Company. Among the various chemicals viz., Carbendazim, Captan and Metalxyl+Mancozeb evaluated as seed treatment under in vivo condition against chickpea wilt, the fungicide Carbendazim at 2 % concentration of all the three companies was most effective, whereas at 1 % concentration Carbendazim of Dhanuka Company was effective and controlled 100 % wilt incidence. Among the various chemicals viz., Copper oxychloride, Chlorothalonil, Mancozeb, Metalxyl+Mancozeb, Captan, Propiconazole and Hexaconazole evaluated as foliar spray under in vivo condition against Alternaria blight disease of onion, the fungicide Hexaconazole of UPL company was most effective, followed by fungicide Metalxyl+Mancozeb of UPL and Captan of Zuari company. The percent control of the disease over PDI for Hexaconazole of UPL was 78.57, followed by Metalxyl+Mancozeb of UPL and Captan of Zuari, which gave % control of the disease over PDI. Other fungicides viz., Copper oxychloride of Rallis, Chlorothalonil of Syngenta, Mancozeb of Dhanuka and Propiconazole of Syngenta gave percent disease control over PDI in the range of Among the various chemicals viz., Copper oxychloride, Chlorothalonil, Mancozeb, Metalxyl+Mancozeb, Captan, Propiconazole and Hexaconazole evaluated as foliar spray under in vivo condition against Alternaria leaf spot disease of Tomato, the fungicide Hexaconazole of UPL and Indofil company and the

18 xviii Abstract contd... Miss Subu Sunya fungicide Propiconazole of Nagarjun and Indofil company was found more suitable. These two fungicides of the said companies gave 100 % disease control. The fungicide Metalxyl+Mancozeb of UPL, Mancozeb of Dupont, Copper oxychloride of Zuari, Chlorothalonil of Coromandel and Captan of Makthesian gave disease control in the range of %. Thus, the fungicide Propiconazole of Nagarjun and Indofil as well as Hexaconazole of UPL and Indofil was most effective for the control of leaf spot of Tomato. Pages 1 to 128

19 1 1. INTRODUCTION Plant diseases and disease causing pathogens causes severe losses in yield of cereals, pulses, oilseeds and vegetable crops. Among pulses wilt of chickpea is an important disease, while among vegetables Alternaria leaf blight of onion and Alternaria blight of tomato are important diseases in Maharashtra state. Wilt of chickpea Chickpea (Cicer arietinum L), also known as Gram or Bengal gram, is the third most important pulse crop after bean (Phaseolus vulgaris) and pea (Pisum sativum) (Vishwadhar and Gurha, 1998), on a world basis, but of first importance in the Mediterranean basin and South Asia, with India accounting for between 60 and 75 % of the world s chickpea production (Barve et al., 2001; Singh and Ocampo, 1997; Tekeoglu et al., 2000). Chickpea is grown in 33 countries on an area that has been estimated at between 6.4 and 10.8 million hectares (FAO, 1988; FAOSTAT, 2001; Jodha and Rao, 1987). Chickpea is particularly an important high protein crop in India as it constitutes a major source of protein in animal feed, the dry stalks and husks, containing small broken pieces of grain obtained during milling, are fed to animals (Malik and Tufail, 1981), and human diet especially for low income group, by supplementing their cereal diets. Although, chickpea is predominantly consumed as a pulse, dry chickpea is also used in preparing a variety of snack foods, sweets and condiments and green fresh chickpeas are commonly consumed as a vegetable.

20 2 About 172 pathogens including fungi, bacteria, viruses and nematodes have been reported to infect the crop, out of which 89 have been reported from India alone (Cother 1977). Ascochyta blight (Ascochyta rabies), wilt (Fusarium oxysporum f. sp. ciceri), black root rot (Fusarium solani) and wet root rot (Rhizoctonia solani) are amongst the serious fungal diseases of chickpea (Nene and Reddy 1987). Wilt complex, which manifests itself by wilting or root rots, is one of the most devastating and challenging disease, which can damage the crop at any stage. Fusarium wilt [Fusarium oxysporum f. sp. ciceri (Padwick) Matuo and K. Sato)] is one of the major yield limiting factors of chickpea (Jalali and Chand, 1992; Dubey et al., 2001). The wilt pathogen is seed-borne (Haware et al. 1978) and can survive in soil in the absence of host for more than six years (Haware et al. 1986). Wilt complex in chickpea is caused by several pathogens however, Sclerotium rolfsii, R. solani, F. oxysporum f. sp. ciceri have been considered as the major pathogens. The disease can appear at any stage of plant growth, symptoms in a highly susceptible cultivar can develop any time between 25 days after sowing till as late as podding stage (Nene 1985). At national level the yield losses encountered due to wilt may vary between five to ten per cent (Singh and Dahiya, 1973).The pathogen is both seed and soil borne; facultative saprophyte and can survive in soil up to six years in the absence of susceptible host (Haware et al. 1978; 1986). The disease is important between the latitudes of 30 N to 30 S of the equator, where the chickpeagrowing season is dry and warm, and has been reported from 23 countries (Nene et al., 1989).Fusarium wilt, is a serious disease of

21 3 chickpea in India, Iran, Pakistan, Nepal, Burma, Spain, Tunisia and Mexico. It has been observed in Morocco, Algeria, and Syria. Nema and Khare (1973) reported that damage caused by the wilt disease is up to 61 % if the attack takes place at the seedling stage and 43 % at the flowering stage. Early stage wilting causes more losses as compared to loss caused by late wilting. Seeds harvested from wilted plants were lighter and duller than those from healthy plants (Haware and Nene, 1980). It causes complete loss in grain yield if the disease occurs in the vegetative and reproductive stages of the crop (Navas et al., 2000). The fungus F. oxysporum f. sp. ciceris, is primarily a soil borne, however, few reports indicated that it can be transmitted through seeds (Haware et al., 1978). Management of Fusarium wilt of chickpea is difficult to achieve and no single control measure is fully effective. The pathogen with its high saprophytic ability can survive in soil for a long period during which it may have to go through different environmental stresses and biological competition which may lead to the existence of physiological races. The most effective and practical method of control worldwide is to use fungicides (Gupta et al., 1988) or resistant cultivars. However, the effectiveness of host resistances is curtailed by the occurrence of pathogenic races in F. oxysporum f.sp. ciceris (Jimenez-Gasco et al., 2004). Thus, there is a need to explore the efficacy of different fungicides to manage this disease below economic threshold level in the absence of resistant cultivars. Alternaria leaf blight of Onion Onion (Allium cepa L.) the queen of kitchen, considered as the poor man s staple spice is flying out of the reach of even

22 4 middle class families. Grown for its bulb and medicinal values, a bulbous, biennial herb, is one of the most important vegetable crops grown in India. Onion accounts for 90 per cent of the exported vegetables from India in terms of value. It belongs to the family Amaryllidaceae and genus Allium and about 300 species of Allium are known. As a vegetable and spice it is used both as tender and mature bulb in our daily Indian diet. On the basis of skin colour there are three types of onion i.e. red onion, yellow onion and white onion. The red colour of onion is due to anthocyanin pigment and yellow colour is due to queracetin pigment. The most important characteristic of onion is its pungency, which is due to volatile oil allyl propyl disulphide. Onion is consumed throughout the year by almost all classes of people on account of its medicinal and dietary value. The young green plants are eaten raw in salads, while the mature bulbs are cooked or eaten raw as vegetable. They are used in soups and sauces and as flavoring agent in many dishes. It is good source of vitamin A, B and C, protein, phosphorous, calcium, ascorbic acid etc. Medicinally, it has been observed that onion promotes appetite, useful against maleria, night blindness, for lowering of blood pressure and against bite of rabid dogs. Its juice with honey is said to be beneficial against weakness of vision. It also suppresses the acidity. It is neither cold nor hot for digestive tract. Onion can be grown in kharif, rabi and summer season. The crop requires low cost of cultivation and gives more yield and good returns to the farmers and also onion bulbs possess good export potential.

23 5 Onion is supposed to have its origin in the Middle East Asian countries and introduced in India from Palestine. It is cultivated throughout the world. In India major onion growing states are Maharashtra, Karnataka, Madhya Pradesh, Bihar, Tamilnadu and Gujarat. Maharashtra is leading state in onion production. In India onion is one of the most important among various Allium crops grown and comprises ha area and 12,970.1 MT of production in In Maharashtra it occupies an area of about 170 ha and production of 2800 M. tones (Anonymous, 2011). The major onion growing districts of Maharashtra are Nashik, Pune, Ahmednagar, Satara, Solapur, Dhule and Jalgaon. Onion crop grows vigorously with soft and lustrous leaves. Also water percentage in leaves is high. Hence many pests and diseases are attracted towards this crop. Several factors have been identified for the low productivity of onion in India. Onion crop is attacked by many diseases, which cause loss in quality and quantity. The diseases such as Purple blotch (leaf blight) caused by Alternaria porri Rao., Downy mildew caused by Peronospora destructor Berk., Rust caused by Puccinia porri Wint., Smut caused by Urocystis cepulae Forst., Damping off caused by Pythium sp., Cercospora leaf spot caused by Cercospora duddiae Well. Neck rot caused by Botrytis allii Munn, Soft rot caused by Erwinia spp., Black mold caused by Aspergillus spp., Dry rot caused by Macrophomina phaseolina, Smudge caused by Colletotrichum circinans, Colletototrichum blight caused by Colletotrichum gloeosporides, Basal bulb rot caused by

24 6 Fusarium oxysporum, Stemphylium blight caused by Stemphylium vesicarium, Pink rot caused by Pyrenochaeta terrestris, White rot caused by Sclerotium cepivorum Bark, Bacterial brown rot caused by Psudomonas aeruginosa are responsible for heavy losses of the crop. Among the foliar diseases, purple blotch is one of the most destructive diseases, commonly prevailing in almost all onion growing pockets of the world, which causes heavy loss in onions under field conditions. The name Purple blotch for this disease was proposed by Nolla (1927). He named the causal organism as Alternaria alli which was later amended to Alternaria porri. The pathogen Alternaria porri destructs the leaf tissues which destroys the stimulus for bulb initiation and delays bulbing and maturation. Severe attack on flowering alliums can completely girdle flower stalks with necrotic tissues, causing their collapse and total loss of seed production capacity. Further, seed infection causes more severe economic loss in seed production also. Alternaria leaf blight of Tomato Tomato (Lycopersicon esculentum Mill.) belongs to the family solanaceae and is one of the most remunerable and widely grown vegetables in the world. Among the vegetables tomato ranks next to potato in world acreage and ranks first among the processing crops. It is a good source of income to small and marginal farmers and contributes to the highest average fruit nutrition of the consumer. It is a native of tropical country said to be originated from Peru, South-America. This crop is intensively cultivated in India. The tomato requires moderately cool weather and is grown in both kharif as well as Rabi season.

25 7 Tomato is grown for its edible fruits, which can be consumed either fresh or in processed form and is a very good source of vitamins A, B, C and minerals. Tomato cultivation has become more popular since mid nineteenth century because of its varied climatic adaptability and high nutritive value. Tomato is being exported in the form of whole fruits, paste and in canned form to West Asian countries, U.K., Canada and USA. Tomato has become the most popular and widely cultivated fruity vegetable in India during the last 50 year. Area under tomato in the country is about 8.65 lakh hectares and it is about 10.2 % of the total cropped land under vegetables. Annual production of tomato in India is 1, 68, 26,000 metric tonnes which is 11.5 % of the total vegetable production and productivity of 19.5 metric tonnes per hectare (Kumar, 2011). There has been a gradual increase in the area under tomato while the production has been fluctuating due to various diseases and insect pest damage. There are several diseases on tomato caused by fungi, bacteria, viruses, nematodes and abiotic factors (Balanchard, 1992). As a canning crop, it takes first rank among the vegetables. It is used as cooked or raw and is made into soups, salads conserves, pickles, catsups and many other products. Fruits consist of large quantity of water and also has high nutritive value which contains vitamin A and B and abundant source of vitamin C. Well matured tomato fruits contain essential amino acids except tryptophane and also good source of sugar like glucose and fructose. It also contains minerals like Mg, Ca, P, Fe, Na, K, Cu and S. The tomato fruit contains proteins 1.9 g, Fats 0.1 g, minerals 0.6 g, fiber 0.7 g, and carbohydrates 3.7 g per 100 g of edible portion,

26 8 which keep our stomach and intestine in good condition. It also ranks high in available calories per unit of dry matter. Hence fruits are mostly used in preparations of salads, soups, chutneys, jams, pickles, ketchups, sauces etc. Tomato is a warm season crop and does well at temperatures ranging from C. It is grown all the year round, where the summer temperatures are moderate. It can be grown on variety of soils, yet well drained sandy loam soil is the best suited. It grows well in neutral soil reaction. Leaf spot of tomato caused by the fungus Alternaria alternata f sp. lycopersici is responsible for significant economic losses incurred by tomato producers each year. This disease produces brown to black, target-like spots on older leaves that may coalesce into larger lesions. Generally, in the beginning the spots remain small and circular or elliptical in shape with colour of spots varying from species to species. These may be pale, brown, olivaceous brown, grayish or black etc. and typically surrounded by halo-chlorotic tissues. Later on, the spots gradually increase in size (varying with species) in a concentric manner and often coalesce, leading to blighted appearance. In case of A. alternata the margins of spots are raised and the zonation is indistinct. The disease starts from lower leaves and slowly progresses towards the upper shoots, leaves, petioles, pods/fruits and heads. Symptoms become prevalent during the hotter months and with high humidity and rain. With the rising vegetable consumption within the country and the emphasis laid on export of vegetables, there is greater need to increase the production of vegetables. Chemical fungicides are most

27 9 commonly used in managing the plant diseases and Chemical control measures have been tested and found effective in the control of diseases (Ogundana and Denis, 1981; Plumbley, 1985). In the management of plant diseases various fungicides particularly seed dressing fungicides, contact fungicides and systemic fungicides are used. The recommended fungicides of same technical name are manufactured by several companies but whether the efficacy of fungicides of same technical name of different companies is same or different is not known. Therefore, it is important to study the efficacy of a known technical fungicide of various brand/company, so as to know that the technical fungicides can be recommended as such or along with the name of manufacturing firm. Therefore, the experiment was undertaken to evaluate the contact and systemic fungicides of same technical name of various firms for their efficacy against wilt pathogen of chick pea, and leaf spot pathogen of tomato and onion. In this context, the present investigations were undertaken with the following objectives. 1. To test the efficacy of different seed dressing, contact and systemic fungicides of different firms against seed borne pathogen, and wilt pathogen of chickpea in vitro and in vivo. 2. To evaluate the efficacy differences of same technical fungicide of various companies on Alternaria leaf blight pathogen of onion in vitro and on leaf blight disease in in vivo, and 3. To evaluate the efficacy of same technical fungicides of different firms on Alternaria leaf blight pathogen of tomato in vitro and on leaf blight disease in in vivo.

28 10 2. REVIEW OF LITERATURE The literature pertaining to the wilt pathogen of chickpea, leaf spot pathogen of tomato and onion along with efficacy of various fungicides for the control of respective pathogen and disease is reviewed as under 2.1 Onion Leaf blight Ajrekar (1923) made first report on leaf spot and blight disease on onion which were threatening the cultivation of onions in Bombay area and attributed it to Alternaria spp. Nolla (1927) observed purple blotch of onion and described the fungus as A. alli Thirumalachar and Mishra. (1953) noticed purple blotch of onion causal agent as A. porri. Pandotra (1964) made first report of Alternaria porri (Ellis) Cif. on onion from Punjab. Pandotra. (1964) reported that yield losses of onion in India caused by Alternaria porri under favourable conditions varies from per cent. Grewal and Pal. (1970) reported losses up to 70 % in some years in Northern India and Pakistan. Tun (1970) documented A. porri (Ellis) Cif. as causing a major disease on onion in Burma. Gupta et al. (1981, 1987) reported that maximum mean percent inhibition of mycelial growth was recorded (98.94 and 100 %) in mancozeb at 0.2 %, followed by companion at 0.2 % (98.40 and %) and azoxystrobin at 0.15 % (95.40 and %). These fungicides were found to be most effective against A. porri

29 11 and S. vesicarium. Among the systemic fungicides, Azoxystrobin (0.1 %) gave maximum mycelial inhibition (94.40 and %), followed by propiconazole at 0.1 % (89.10 and %). Ogundana and Denis, (1981) found Chemical control measures effective in the control of diseases. Sharma (1986, 1987) reported good control of the pathogen on onion (Allium cepa L.) with different concentrations and sprays of mancozeb. Gupta et al. (1991) also reported good control of the pathogen on onion (Allium cepa L.) with different concentrations and sprays of mancozeb. Patil and Patil (1991) concluded Alternaria blight of Onion is the most predominant and severe disease in the onion growing centers of Maharashtra. Gupta et al. (1994) indicated that in the survey conducted by the Foundation, only Stemphylium blight (Stemphylium vesicarium) and purple blotch (A. porri) diseases were identified as of national importance. Srivastava et al. (1994) studied the status of field diseases in onion in India and reported that purple blotch (A. porri) incidence was high ( %) in both Kharif and Rabi seasons when high humidity prevailed, during the five years of the survey ( ). Sugha (1995) reported that three foliar sprays of 0.1 % alone or in combination with copper oxychloride 0.1 % and mancozeb 0.1 % resulted in 53.5 to 62 % protection to the crop.

30 12 Clove dip in iprodione 0.25 % for 1 hr before sowing followed by 2 sprays of metalaxyl + mancozeb (Ridomil 0.25 %) or 0.2 % proved highly effective, giving % control of the disease. Iprodione and metalaxyl + mancozeb were superior to chlorothalonil, copper oxychloride, mancozeb and zineb in providing protection to garlic crop from purple blotch in Himachal Pradesh. Deshmukh et al. (2007) tested efficacy of fungicidal spray against purple blotch of onion caused by Alternaria porri (Ellis) Cif. Eight different fungicides were tested on highly susceptible variety Pilipatti under net house conditions. Maximum disease control (79.58 %) was recorded in foliar application of a mixture of hexaconazole (0.005 %) + mancozeb (0.3 %) followed by difenoconazole (0.025 %) + mancozeb (0.3 %) in reducing disease intensity (78.58 % and %) as well as avoiding yield loss by and per cent, respectively over control. Chethana et al. (2011) tested three non systemic fungicides viz., mancozeb, iprodione and copperoxychloride and three systemic fungicides viz., difenconazole, kitazin and propiconazole against Alternaria porri causing purple blotch of onion under in vitro conditions. Among systemic fungicides tested difenconazole at 0.1 percent showed per cent inhibition of the fungus while among the non-systemic fungicides mancozeb at 0.3 per cent was best in inhibiting the growth of Alternaria porri with 100 percent inhibition. Swati Dumbre et al. (2011) studied the efficacy of different fungicides viz. carbendazim, benlate, and thiram and combination treatment of carbendazim + thiram against seed borne

31 13 infection. Carbendazim + thiram treatment 3 g kg -1 was significantly superior in all parameters as compared to other treatments in controlling seed borne infection. Mishra and Gupta (2012) tested eight fungicides, out of which, Mancozeb at 0.2 % completely inhibited the growth of both the pathogens i.e, purple blotch and stemphylium blight of onion. Azoxystrobin (0.1 %), propiconazole (0.1 %) and antracal (0.2 %) were the other effective fungicides. 2.2 Tomato Leaf Blight: Abdulsalam and Mussa (1991) tested four fungicides in the laboratory for the control of the fungi on PDA and as seed treatment. Bavistin unlike dithane and miceb did not affect A. alternata at all. In soil artificially infested with A. alternata, seeds treated with bavistin, mancozeb and miceb significantly increased emergence over the untreated control, while vinclozolin was the least effective fungicide. Bhardwaja (1991) reported that sequential application of captofol, mancozeb and copper oxychloride (all at 0.25 %) 40, 55, 70 days after transplanting increased yield by 50.5 % by reducing the incidence of A. solani. Maheswari et al. (1991) conducted field trials using six fungitoxicants. The most effective control of A. solani was given by copper oxychloride(64.7 %) followed by mancozeb (61.7 %). Sattar and Kaseem (1991) studied the effectiveness of Rovral (Iprodione), Dithane M- 45, zineb, topsin M-7 and Ridomil 5G. Among these iprodione gave the best control. Maximum yield was recorded with 5 % iprodione treatments.

32 14 Sinha and Prasad (1991) reported that the best control of the disease caused by Alternaria solani was given by Dithane M- 45 (Mancozeb) at 0.2 % among 7 fungicides tested in the field over 3 seasons. The treatment was also the most cost effective and gave the highest yields. Choulwar and Datar (1992) reported that out of 9 fungicides viz. Copper oxychloride,zineb, ziram, mancozeb, carbendazim, Dithionon, Thiophenate methyl, Iprodione and captafol tested against early blight of tomato, mancozeb was the most effective in reducing disease intensity and increasing the yield, followed by captofol and zineb. Brammatta (1993) reported that application of chlorothalonil (0.2 %) decreased early blight severity. However, application did not affect the yield of any cultivar, nor were fungicide cultivar interactions detected. Cultivar differed in the extent of defoliation resulting from early blight. Area under disease progress curve in the cultivar celebrity was not affected by fungicide application. Generally weight, number of fruit harvested and the mean fruit weight rose significantly among cultivars. Maheshwari and Mehta (1993) tested 5 fungicides as leaf spray against Alternaria solani and Phytopthora infestans over two seasons. The most effective control was given by Dithane M-45 (Mancozeb) with an increase in yield of %. Patel (1993) observed 5.74 and 7.49 per cent spore germination of A. alternata after 96 hrs of incubation in copper oxychloride (3000 ppm) and mancozeb (3500 ppm), respectively. Choulwar and Datar (1994) studied the tolerance of A. solani to fungicides like mancozeb, captofol, thiophenate methyl

33 15 and carbendazim at 1000, 1500, 2000, 2500 ppm concentration in vitro. The results indicated that A. solani could tolerate 2500 ppm of all the fungicides tested. Devanathan and Ramanujan (1995) tested five fungicides viz. carbendazim, captafol, mancozeb, copperoxychloride and chlorothalonil to the infection of A. solani in tomato and reported that Mancozeb gave the best control and highest crop yield followed by chlorothanonil and copperoxychloride. Patil et al. (1995) studied the persistence of mancozeb in tomato. They reported the successful control of early blight of tomato by three or four sprays of mancozeb. Shyam and Gupta(1996) reported efficacy of Ridomil MZ and Indofil M-45 against Alternaria leaf spot of tomato. Dillard et al. (1997) reported that three sprays of mancozeb 75 WP at 0.2 per cent gave significantly better control of early blight caused by Alternaria solani and stabilized higher marketable yield with reducing incidence of alternaria fruit rot. Likewise, the highest usable yields of tomato with greater financial benefits obtained in chlorothalonil or mancozeb at 7 and 10 days interval treatments was primarily due to suppression of Alternaria and other fruit rot. Jovaneev (1998) studied the efficacy of Acrobat plus (dimethomorph + mancozeb) and mancozeb 80 WP for controlling late blight (Phytophthora infestans) and early blight (A.solani) diseases of tomato. Ridomil MZ-72 WP (metolaxyl + mancozeb) and Dithane M-45 (Mancozeb) were used as standards in the tests. Acrobat plus and mancozeb 80 WP used at 2.0 and 2.5 kg/ha

34 16 showed similar efficacies to the two standard fungicides. Ridomil MZ-72 showed a greater efficacy against P. infestans than A. solani. Kamble et al. (2000) Reported that among the six fungicides tested against tomato leaf spot pathogen Alternaria alternata, mancozeb was found highly effective in inhibiting the mycelial growth followed by copper oxychloride and iprodione at 1000, 2000 and 3000 ppm. Mancozeb was also found effective in reducing the disease intensity under pot culture condition at 0.2 per cent concentration. Naveen kumar Singh et al. (2001) noticed the best control of leaf blight disease of tomato caused by A. solani by 3 foliar sprays of Dithane M-45 (0.2 %) at 15 days interval. Patil et al. (2001) evaluated the efficacy of two fungicides viz., carbendazim 0.05 per cent and mancozeb 0.25 per cent in the field trial for the management of early blight of tomato caused by Alternaria solani. The lowest per cent disease incidence was observed in the treatment of carbendazim (13.93) and mancozeb (15.46). Similarly, the highest yield of tomato fruits was recorded in the treatment of carbendazim ( q ha super (-1)) followed by mancozeb ( q ha super (-1)) when sprayed five times at an interval of 15 days starting from the initiation of the disease. Sawant and Desai (2001) studied the efficacy of Dodine 65 WP and Mancozeb 75WP with alachlor 50 EC and acephate 75 SP against early blight (Alternaria solani) on tomato. Disease incidence was maximum during Kharif (44 %) and during winter (22.17 %) at 65 days after transplanting. The most effective treatment against early blight was spraying of alachlor before transplanting + 2 applications of dodine + 2 applications of

35 17 acephate. Alachlor and acephate applied in plots treated with Mancozeb and Dodine had no adverse effect on the efficacy of the fungicides. Fugro and Mandokhot (2002) reported that crop transplanted during 45 th meteorological week (5 th November) and sprayed with mancozeb produced significantly higher yield of tomato and the incidence of blight was significantly lower in the said treatment. Prasad and Naik (2003) tested the efficacy of nonsystemic fungicides (Iprodione, mancozeb, copper oxychloride and SAAF), and systemic fungicides (Thiophenate methyl,triadimefon benomyl and carbendazim) in controlling the early blight of tomato. Mancozeb treatment gave the highest cost-benefit ratio of 1:11.4 in addition to reducing the disease incidence. Patil et al. (2003) evaluated the efficacy of fungicides, i.e carbendazim (0.05 %) and mancozeb (0.25 %), botanicals i.e. neem seed and leaf extract (each at 5 %) concentration and tobacco decoction (2 %) in a field experiment for the management of early blight of tomato. The lowest per cent disease incidence (PDI) was observed in carbendazim (13.93) and Mancozeb (15.46) treatments. Similarly the highest yield of tomato fruits was recorded with carbendazim ( q/ha) followed by mancozeb ( q/ha). The plant products, namely neem seed extract (19.75 PDI), neem leaf extract (20.36 PDI) and tobacco decoction (23.87 PDI) were also effective in reducing disease incidence and increasing fruit yield by , and q/ha, respectively. Tofoli et al. (2003) evaluated the effectiveness of various groups of fungicides for controlling early blight (Alternaria solani) as

36 18 well as their effect on tomato fruit yield, following early blight severity in leaf lets and stems; percentage of leaf drop; incidence of healthy, infected and sun-damaged fruits; yield and the percentages of large, medium and small sized fruits were evaluated. The highest levels of disease control, quality and increase in fruit yields were obtained with pyraclostrobin + metiram, fenamidone + chlorothalonil, famoxadone + cymoxanil + Mancozeb, kresoximmethyl, azoxystrobin, difenconazole, tebuconazole,pyrimethanil, cyprodinil, famoxadone + mancozeb followed by prochloraz, fluazinam,procymidone, iprodione, mancozeb and chlorothalonil. Abhinandan et al. (2004) tested the efficacy of commercial fungicides Dithane M-45(mancozeb) at 0.25 %, Kavach at 0.25 %, Rovral (iprodione) at 0.20 %, Blitox (copperoxychloride) at 0.25 %, Syllit (dodine) at 0.3 %, Antracol (propineb) at 0.15 %, Tilt(propiconazole) at 0.05 % and Topaz (penconazole) at 0.05 % in controlling the disease.dithane M-45, followed by Kavach were found to be very effective in controlling the disease with >50 % disease control compared to the control treatment. Sobolewski and Robak (2004) tested the fungicides Unikat 75 WG (zoxamide (mancozeb), ethaboksam (ethaboxam). MC 72.5 WP (mancozeb) cymoxanil and Acrobat MZ69 WP, dimethomorphyl (mancozeb) to control late blight (Phytophthora infestans) and early blight(a.solani) in tomato. The organic products grevit 200 SL and crop set, applied alternatively at 7-day intervals with Acrobat MZ 69 WP gave satisfactory control of the complex fungal and bacterial diseases. Kamal et al. (2007) found that Alternaria blight and Alternaria fruit rot of tomato were lower when foliar spray was done

37 19 with Indofil M-45, with disease incidence of 1.7 % and 4.0 %, respectively. Hossain and Hossain (2009) tested seven fungicides for their effectiveness against early blight (Alternaria solani L.) of tomato. The fungicides were Dencozeb 80WP (Mancozeb), Evamil 72WP (Mancozeb 64 % + Metalxyl 8 %), Mosum 80WP (Mancozeb), Companion 72WP (Mancozeb 60 % + Carbendazim 12 %), Mancovit 70WP (Mancozeb), Baimyl 72WP (Mancozeb 64 % + Matalxyl 8 %) and Pesterozeb 50WP (Mancozeb). In an in-vitro study all the test fungicides at 250 ppm significantly inhibited the mycelial growth of Alternaria solani over control and Baimyl, Mancovit and Evamil gave complete inhibition of mycelial growth. In the field trials, all the fungicides significantly reduced disease severity and increased fruit yield and yield component. 2.3 Chickpea Wilt Kovacikova (1970) reported that seed treatment with 2 gm per kg seed gave the best protection against the Fusarium wilt of chickpea caused by F.oxysporum f. sp. ciceri. Westerlund et al. (1974), in experiments under controlled conditions, observed that the first symptom of wilt was yellowing of lower leaves of young plants and this chlorosis progressed uniformly upwards. Cother (1977) obtained effective control of gram wilt by seed treatment with Thiram, Benomyl and Captan. Verma and Vyas (1977) reported effective control of chickpea wilt (F.oxysporum f. sp. ciceri) with Carbendazim (0.1 %) and Chloroneb (0.1 %).

38 20 Haware et al. (1978) reported effective control of chickpea wilt with seed treatment of Thiram + Benomyl. Haware et al. (1978) reported that the Fusarium oxysporum f.sp. ciceri is also seed-borne and may therefore spread by means of infected seed. Haware and Nene (1982) reported Fusarium oxysporum races 1, 2, 3 and 4 to be present in India. Jones et al. (1982) reported some effective means of controlling Fusarium oxysporum which include disinfection of the soil and planting material with fungicidal chemicals. Nene (1985) reported that Fusarium oxysporum f. sp. Ciceri cause losses as high as % when conditions favour disease. Taya et al. (1990) tested eight fungicides, alone or in combination with thiram, as seed treatment, pre-sowing soil drench and seed treatment + drenching after sowing with different levels of N and P. They observed that increased levels of P enhanced the effectivity of carbendazim and carbendazim + thiram, applied as seed treatment or pre-sowing drenching, while increased level of N reduced the affectivity of fungicide. Abdulsalam and Mussa (1991) tested four fungicides in the laboratory for the control of the fungi on PDA and as seed treatment. In their experiment bavistin significantly affected F. oxysporum followed by mancozeb and miceb while vinclozolin was the least effective fungicide. Ilyas et al. (1992) tested 10 fungicides against the mycelial growth of F. oxysporum f.sp. ciceris and reported that