Nội dung

Int.J.Curr.Microbiol.App.Sci (2019) 8(12): 621-627 International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 8 Number 12 (2019) Journal homepage: http://www.ijcmas.com Original Research Article https://doi.org/10.20546/ijcmas.2019.812.081 Pathogenicity Diversity in Albugo candida Isolates causing White Rust Disease in Rapeseed-Mustard Devanshu Dev*, G. R. Daniel, Pooja Upadhyay and A. K. Tewari Department of Plant Pathology, College of Agriculture, G B Pant University of Agriculture and Technology, Pantnagar-263145, Uttarakhand, India *Corresponding author ABSTRACT Keywords Coalesced, Pathogenicity diversity, Oilseed crop, Biotic stress, White rust Article Info Accepted: 07 November 2019 Available Online: 10 December 2019 Albugo candida causing white rust of rapeseed-mustard is a highly variable fungus and cause great economic losses. In this study 44 A. candida isolates belongs to 17 different states of India has been used for the pathogenicity diversity. Symptomatology of the pathogen i.e. pustule pattern, pustule size and pustule colour has taken as criteria for the pathogenicity diversity. All the 44 A. candida isolates were inoculated on susceptible Brassica juncea cultivar Varuna for the study. In the study of white rust symptoms of 44 A. candida on Varuna cultivar five different types of pustule pattern has been observed viz. viz. Separate circular; Coalesced circular, Scattered and pin head; Restricted near veins and veinlets and Restricted near veins and veinlets separate or coalesced circular type pustules. Pustules size among 44 A. candida isolates was varied from 0.5-2.5mm while pustule colour of all the isolates was creamy white. The study very less pathogenicity diversity in pustule size and colour has been observed among 44 A. candida isolates, while in pustule pattern some diversity was observed. Introduction Oilseed brassica is one of the most important oilseed crop of tropical and subtropical countries. Rapeseed-mustard affected by different biotic stress, among them white rust caused by A. candida is a major disease, causing heavy economic losses. It is estimated that the floral and leaves infection can cause losses from 20-60 per cent (Kolte, 2002; Khunti et al., 2003; Sachan et al., 2004; Kumar and Kalha, 2005) and up to 36.88 per cent (Bal and Kumar, 2014) in mustard. White rust symptoms are characterised as local and systemic. In case of local infection, symptoms of the disease appear primarily on the lower surface of leaves and manifested by the appearance of minute or small, white or 621 Int.J.Curr.Microbiol.App.Sci (2019) 8(12): 621-627 creamy yellow raised scattered and circular pustules (1 to 2 mm in dia.) which later coalesce to form patches. Systemic infection symptoms include distortion, hypertrophy, hyperplasia and inflorescence sterility. This infection phase has been known as the stag head. The flowers affected show malformation, the petals become green sepals and the stamens can be transformed into a leaf-like structure or a carpel. The petals and stamens persist in the flower, as in normal flowers, rather than falling early. Sometimes the stamens become thick clubshaped sterile bodies. Usually the ovules and pollen grains are atrophied and result in incomplete sterility (Kolte, 1985). Yield loss is greater in case of systemic than local infection (Harper and Pittman, 1974; Petrie, 1973; Verma and Petrie, 1980). At maturity stage, stag heads are with thick-walled brown oospores that have been appeared to survive in dry form for a more than 20 years (Verma and Petrie, 1975). A. candida isolates from different geographical regions and different host may be different in their incubation period, latent period and production of sporangia and zoospores, pustule size, shape and texture and aggressiveness (Lakra and Saharan, 1988; Gupta and Saharan, 2002; Patni et al., 2005 and Mishra et al., 2009). This indicated that there may be the possibilities of variability within A. candida isolates. The high variability of A. candida makes it a highly virulent pathogen, which is difficult to manage. The study of variability is needed to find out the status of variability, there occurrence and evolution pattern so that it will be helpful in the development of resistant varieties against the disease. Therefore, in this study pathogenicity variability of 44 A. candida isolates has been done. Materials and Methods Forty four A. candida isolates collected from Oilseed Pathology Laboratory, Department of Plant Pathology were belonging to 17 states of India and also from 10 different Brassica spp. The description of A. candida isolates used in the studies is given in the table below (Table 1). Isolation and purification of white rust inoculum The isolation and purification of all A. candida isolates were done on susceptible B. juncea cv. Varuna grown under glasshouse. The seedlings were raised in plastic pots containing sterilized soil. The fresh sporangial suspension was prepared with single pustule in a glass vial contained 1-2ml sterile distilled water. The suspension was mixed properly and kept it at 10°C for overnight for the release of zoospores. Although, freshly prepared sporangial suspension has also used for the inoculation without any incubation period. The sporangial concentration in the suspension was maintained about 2.5×10 5 zoosporangia per ml using haemocytometer. The seedlings at cotyledonary stage (7-8DAS) were inoculated with 10μl spore suspension through inoculating micropipette on each and every lobes of cotyledon of the seedlings. After inoculation plants were transfer to plant propagator box and kept the box in a dark room for 72hrs, with a relative humidity of more than 90 per cent and of 18±20C temperature. After three days plants were taken out and kept in glasshouse where, proper temperature (18±2 0C) and humidity (>80%) were maintained during the entire plant growth and disease appearance period. When disease appeared (10-15DAI), infected leave samples were collected before yellowing of the leaves and preserved at low temperature (4°C- 10°C) by 622 Int.J.Curr.Microbiol.App.Sci (2019) 8(12): 621-627 keeping it in butter paper bags for further studies. The pustule pattern of all 44 A. candida isolates were observed and recorded. Likewise, pustule dia. of 10 randomly selected leaves of an isolate were taken in mm. Analysis of mean pustule size of all 44 A. candida isolates has been done through Duncan’s Multiple Range Test (DMRT) using SPSS 16.0 version software to find out whether there is significant difference between the mean pustule size. Pustule colour in symptomatic leaves of each isolate was observed and recorded. Results and Discussion The pathogenicity diversity of 44 A. candida isolates has been done on the B. juncea cv. Varuna. The colour of pustules of all the isolates was creamy white in colour. The pustule pattern of all the isolates has been observed visually and categorized in 05 different types of pustule pattern viz. Separate circular; Coalesced circular, Scattered and pin head; Restricted near veins and veinlets and Restricted near veins and veinlets separate or coalesced circular type pustules. Nine showed separate circular type, 16 of coalesced circular type, 12 of scattered pin head type, 04 of restricted near vein and veinlet type and 03 of restricted near vein and veinlet separate or coalesced circular type of pustule (Table 2). The variation in pustule pattern of 33 A. candida isolate indicated different level of pathogenicity diversity. The isolates that formed different pustule pattern could be of different pathotypes. The similar type of observations has been reported by Pandey et al., (2013) where pinhead raised pustules were observed in isolates of Pantnagar, Delhi, Bharatpur, Hisar, Kangra, and Jammu, while pinhead scattered pustules in isolates of Ludhiana. Based on pustules pattern 33 A. candida isolates were grouped in 05 pathotypes. In Duncan’s multiple range test (DMRT) of mean pustule size of A. candida isolates varied from 0.5-2.5mm in dia. The lowest mean pustule size i.e. 0.5mm dia. was observed in Ac-MMP (B. juncea cv. Maya, Morena, MP) while, highest mean pustule size i.e. 2.5mm dia. was observed in Ac-BjV (B. juncea cv. Varuna, Pantnagar, Uttarakhand), Ac-Knp (Kanpur, UP) etc. The mean pustule size was 1.59mm dia. In DMRT of mean pustule size of 44 A. candida isolates, less variability has been observed (Table 3). The similar type of observations has been reported by Pandey et al., (2013) the small size pustules (0.5-1.5 mm) was observed in New Delhi and Hisar isolates of A. candida, while large size pustules (1-3 mm) in Pantnagar and Ludhiana isolates of A. candida. In this study pathogenicity diversity of A. candida isolates has been observed based on symptomatological observations. The significant diversity has been observed in pustule pattern of different A. candida isolates which could be utilized for the further study. While, in case of pustule colour and pustule size of A. candida isolates, there was no significant difference observed. 623 Int.J.Curr.Microbiol.App.Sci (2019) 8(12): 621-627 Table.1 S.No. Host Place State 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. Isolate Name Ac-BjV Ac-Brai Ac-Brys Ac-BjBio Ac-Br Ac-Bni Ac-Bna Ac-BjK Ac-Orai Ac-Kw Ac-Knp B. juncea cv. Varuna Banarasi rai B. rapa yellow sarson B. juncea cv.Bio-YSR B. rugose B. nigra B. napus B. juncea cv.Kranti Ornamental rai Kattili weed B. juncea Pantnagar Uttarakhand Kanpur Uttar Pradesh 12. Ac-Met B. juncea Meerut 13. Ac-Fzb B. juncea Faizabad 14. Ac-Alw B. juncea Alwar 15. Ac-Bhrtp B. juncea Bharatpur 16. Ac-Kot B. juncea Kotputli 17. Ac-Sgn B. juncea 18. Ac-Knc B. juncea Sri Ganganagar Kannahalli 19. Ac-Bnglr B. juncea Bangalore 20. Ac-Ldh B. juncea Ludhiana 21. Ac-Abr B. juncea Abohar 22. 23. 24. 25. Ac-VND Ac-PbND Ac-BcND Ac-UD B. juncea cv. Varuna B. juncea cv. PusaBahar B. carinata cv. BCS-1 B. juncea IARI IARI IARI UDSC New Delhi 26. Ac-Hsr B. juncea Hisar Haryana 27. Ac-Krnl B. juncea Karnal 28. Ac-Srsa B. juncea Sirsa 29. Ac-BR B. juncea Pusa, 624 Rajasthan Karnataka Punjab Bihar Latitude & Longitude 29° 02' 60" N 79° 30' 59" E 26°26'59.6"N 80°19'54.8"E 28° 59' 4'' N 77° 42' 21'' E 26° 46' 12'' N 82° 9' 0.00'' E 27° 33' 39'' N 76° 37' 30'' E 27° 13' 1'' N 77° 29' 22'' E 27° 42' 13''N 76° 12' 4'' E 29° 54' 13'' N 73° 52' 37'' E 12° 52' 15''N 76° 47' 18''E 12° 58' 20'' N 77° 34' 50'' E 30° 54' 3'' N 75° 51' 26'' E 30° 08' 40" N 74° 11' 43" E 28° 37' 55'' N 77° 8' 19'' E 28° 38' 41'' N 77° 13' 0'' E 29° 9' 6.69'' N 75° 43' 16'' E 29° 41' 8.2'' N 76° 59' 25'' E 29° 32' 11'' N 75° 1' 31'' E 25°51′39’’N Int.J.Curr.Microbiol.App.Sci (2019) 8(12): 621-627 30. Ac-Kng B. juncea Samastipur Kangra 31. Ac-Smr B. juncea Sirmaur 32. Ac-Psb B. juncea Ponta Sahib 33. 34. 35. 36. 37. Ac-PbMP Ac-VdMP Ac-MMP Ac-VMP Ac-Jam B. juncea cv. Pusa bold B. junceacv. Vardan B. junceacv. Maya B. junceacv. Varuna B. juncea Morena Madhya Pradesh Chatha 38. Ac-Meg B. juncea Umiam Jammu & Kashmir Meghalaya 39. 40. 41. Ac-WB Ac-AWB Ac-Asm B. juncea Amaranthus B. juncea Kolkata Kolkata Jorhat West Bengal 42. Ac-MZ B. juncea Aizawl Mizorum 43. Ac-Mnp B. juncea Imphal Manipur 44. Ac-SK B. juncea Marchak Sikkim Himachal Pradesh Assam 85°46’56’’E32° 5' 59'' N 76° 16' 8'' E 30° 38' 24''N 77° 26' 24''E 30° 26'16''N 77°37' 26''E 26° 30' 0.0'' N 78° 0' 0.00'' E 32° 43' 58'' N 74° 51' 51'' E 25° 34' 0.1'' N 91° 52' 59'' E 22° 34' 21'' N 88° 21' 50'' E 26° 45' 28'' N 94° 12' 35'' E 23° 43' 37'' N 92° 43' 3.4'' E 24° 48' 50'' N 93° 57' 1.0'' E 27° 19' 48'' N 88° 37' 12'' E Table.2 Grouping of A. candida isolates based on pustule pattern Group 1. 2. Pustules Pattern Separate and circular type pustules Coalesced circular type pustules 3. Scattered, pin head type pustules 4. Restricted near veins and veinlets type Pustules Restricted near veins and veinlets separate or coalesced circular type Pustules 5. A. candidaisolate Ac-Brai, Ac-Brys, Ac-Bna, Ac-Orai, Ac-Met,AcAlw,Ac-Bhrtp, Ac-Ldh, Ac-VND Ac-BjV, Ac-BjK, Ac-Br,Ac-Kw, Ac-Knp, Ac-BcND, Ac-Hsr, Ac-Krnl, Ac-BR, Ac-Kng, Ac-PbMP, AcVMP, Ac-MMP, Ac-Jam, Ac-Meg, Ac-Mnp Ac-BjBio, Ac-Bni, Ac-Knc, Ac-Bnglr, Ac-PbND, AcSmr, Ac-WB,Ac-AWB, Ac-Sgn, Ac-Asm, Ac-MZ, Ac-SK Ac-Fzb, Ac-Psb, Ac-VMP, Ac-UD Ac-Abr, Ac-Srsa, Ac-Kot 625 Int.J.Curr.Microbiol.App.Sci (2019) 8(12): 621-627 Table.3 Duncan’s multiple range tests for mean pustule diameter Sr. No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 A. candida isolate Ac-BjV Ac-Brai Ac-Brys Ac-BjBio Ac-Br Ac-Bni Ac-Bna Ac-BjK Ac-Orai Ac-Kw Ac-Knp Ac-Met Ac-Fzb Ac-Alw Ac-Bhrtp Ac-Kot Ac-Sgn Ac-Knc Ac-Bnglr Ac-Ldh Ac-Abr Ac-VND Ac-PbND Ac-BcND Ac-UD Ac-Hsr Ac-Krnl Ac-Srsa Ac-BR Ac-Kng Ac-Smr Ac-Psb Ac-PbMP Ac-VdMP Ac-MMP Ac-VMP Ac-Jam Ac-Meg Ac-WB Ac-AmWB Ac-Asm Ac-MZ Ac-Mnp Ac-SK Mean SEM Average pustule size (mm) 2.5c 1.0ab 1.5abc 1.5abc 1.5abc 2.0bc 2.0bc 1.5abc 1.0ab 1.5abc 2.5c 2.5c 1.0ab 2.0bc 2.0bc 1.0ab 0.8a 2.5c 2.5c 2.0bc 1.0ab 1.0ab 1.0ab 1.0ab 2.5c 2.5c 1.0ab 0.5a 2.5c 1.5abc 2.5c 1.0ab 2.0bc 1.0ab 0.5a 2.0bc 2.5c 1.0ab 2.0bc 2.0bc 0.8a 0.8a 1.0ab 1.5abc 1.59 0.07 626 Int.J.Curr.Microbiol.App.Sci (2019) 8(12): 621-627 References Bal, R.S., Kumar, K. and Singh, P. 2014. Epidemiology and management of white rust and Alternaria blight of Indian mustard. Agric. Res. J. 51: 146149. Gupta, K. and Saharan, G.S. 2002. Identification of pathotypes of Albugo candida with stable characteristic symptoms on Indian mustard. J. Mycol. Pl. Pathol. 32: 46-51. Harper, F.R. and Pittman, U.J. 1974. Yield loss by Brassica campestris and Brassica napus from systemic stem infection by Albugo curciferamm. Phytopathol. 64: 408-410. Khunti, J.P., Khandar, P.R. and Bhoraniya, M.F. 2003. Field evaluation of mustard (Brassica juncea L.) genotypes against white rust (Albugo cruciferarum S.F. Gray). Agric. Sci. Dig. 23:57–58. Kolte, S.J. 1985. Diseases of annual edible oilseed crops. Volume II: Rapeseed mustard and sesame diseases. CRC Press, Inc., Boca Raton, Florida. 135 p Kolte, S.J. 2002. Diseases and their management in oilseed crops. In Rai, M., Singh, H. and Hedge, D.M. (Eds.), New paradigm in oilseeds and oils: research and development needs (pp. 244–252). Hyderabad, India: Indian Society of Oilseeds Research. Kumar, S., and Kalha, C.S. 2005. Evaluation of rapeseed–mustard germplasm against white rust and Alternaria blight. Ann. Biol. 21: 73–77. Lakra, B.S. and Saharan, G.S. 1988. Morphological and pathological variations in Albugo candida associated with Brassica species. Indian J. Mycol. Pl. Path. 18:149-156. Mishra, K.K., Kolte, S.J., Nashaat, N.I. and Awasthi, R.P. 2009. Pathological and biochemical changes in Brassica juncea (mustard) infected with Albugo candida (white rust). Pl. Pathol. 58: 80-86. Pandey, P., Tewari, A.K. and Awasthi, R.P. 2013. Morphological and pathogenic variability of Albugo candida isolates causing white rust in rapeseedmustard. The Bioscan 8(3):835-838. Patni, C.S., Singh, A., and Awasthi, R.P. 2005. Variability in Albugo candida causing white rust disease of rapeseedmustard. J. Res. SKUAST-J. 4: 184191. Petrie, G.A. 1973. Diseases of Brassica species in Saskatchewan, 1970-72. I. Staghead and aster yellows. Can. Plant Dis. Surv. 53: 19-25. Sachan, J.N., Singh, A., Kolte, S.J., Prasad, L. and Singh, B. 2004. Evaluation of mustard germplasm against Albugo candida. Cruciferae Newsletter. 25: 87–88. Verma, P.R. and Petrie, G.A. 1975. Germination of oospores of A. candida. Can. J. Bot. 53: 836-842. Verma, P.R. and Petrie, G.A. 1980. Effect of seed infestation and flower bud inoculation on systemic infection of turnip rape by A. candida. Can. J. Plant Sci. 60: 267-271. How to cite this article: Devanshu Dev, G. R. Daniel, Pooja Upadhyay and Tewari, A. K. 2019. Pathogenicity Diversity in Albugo candida Isolates causing White Rust Disease in Rapeseed-Mustard. Int.J.Curr.Microbiol.App.Sci. 8(12): 621-627. doi: https://doi.org/10.20546/ijcmas.2019.812.081 627