Scientists

Brief Summary of Research Achievements

Quarantine processing of germplasm:

• Quarantine processing of germplasm under Import: Over the years,  exotic germplasm and trial material samples of over 65 crops and their wild relatives from 40 countries processed for quarantine resulted in the interception of various pathogenic fungi and bacteria of quarantine significance included: Peronospora manshurica (downy mildew of soybean), Uromyces betae (beet rust), Fusarium oxysporum f.sp.cucumerinum (fusarium wilt in cucumber) which are not reported from India; Septoria nodorum (glume blotch) has limited distribution; Bipolaris maydis (maydis blight), B. oryzae (helminthosporium leaf spot), Phoma betae (black leg), Puccinia carthami (safflower rust), P. helianthi (sunflower rust), Xanthomonas  campestris pv. campestris (black rot of crucifers) and X. vesicatoria (bacterial spot of tomato and pepper) which are known to possess a large number or more virulent races; Botrytis cinerea, Fusarium solani and B. sorokiniana which have a wide host range.

      A perusal of literature indicated that 10 species of various fungi and one bacterium have been intercepted on 21 new unrecorded hosts’ world over. These included: Coriandrumsativum new host for Botrytis cinerea; Amblyopyrum muticum, Astragalus cicer, Calycophyllum spruceanum,  Elytrigia juncea, E. repens for Claviceps  purpurea; Clitoria ternatea and Macrotyloma uniflorum for Colletotrichum dematium; Medicago spp. and Sesbania rostrata for C. gloeosporioides; Pennisetum typhoides for Drechslera halodes; Sorghum bicolor for D. setariae; Lycopersicon esculentum, Pennisetum glaucum, P. typhoides and Zea mays for D. sorghicola; Lycopersicon spp. for D. sorokiniana; Annona atemoya, Ipomoea spp., Jasmine spp., M. uniflorum and  Prunus persica for Fusarium solani; Oryza sativa for Verticillium albo-atrum and Hibiscus cannabinus for Pseudomonas syringae pv. syringae.

• Quarantine processing of imported transgenic germplasm: Over the years, exotic germplasm samples of transgenic crops (Brassica spp., Cicer arietinum,Glycine max, Gossypium spp., Nicotiana tabacum, Oryza sativa, Solanum tuberosum, Triticum spp., and Zea mays) were processed for quarantine inspection and clearance and intercepted:  fungi - Alternaria brassicae, A. brassicicola, A. longipes, Drechslera oryzae, D. halodes, D. tetramera,Fusarium moniliforme, F. oxysporum f.sp. vasinfectum, F. semitectum, Peronospora manshurica, Phoma lingam, P. sorghina and bacterium- Xanthomonas campestris pv. campestris of quarantine significance.
• Seed health testing of Indigenous germplasm for pest free conservation in National gene Bank: Indigenous germplasm samples of various crops and their wild relatives collected from different parts of the country were processed for quarantine examination. Various fungi viz., Colletotrichum gloeosporioides on V. Mungo from Cuttack; Drechslera oryzae on Oryza sativa fromAlmora, Bhowali,  Arunachal Pradesh, M. P., Meghalaya & Orissa; D. sorghicola on C. tetragonoloba from Jodhpur; Fusarium moniliforme on several crops from many states; Macrophomina phaseolina on Bauhinia semla from Hyderabad, on Glycine max from Arunachal Pradesh; Ustilaginoidea virens on O. sativa from Almora, Bhowali, Cuttack and Umiam etc.  were detected associated with the indigenous germplasm. The infected samples were salvaged by removing discoloured, deformed and abnormal seeds by examining visually and with the aid of magnifying lenses; stereo-binocular microscopes and samples free from fungi and bacteria were released for conservation in National Gene Bank at NBPGR.                  

      A perusal of literature indicated that Nelumbo nucifera for Botryodiplodia theobromae in A.P.; Trichosanthes palmata for Colletotrichum gloeosporioides and Cucumis spp.for Fusarium equiseti in M.P.; Sorghum vulgare for Gloeocercospora sorghi in T.N.; Vigna mungo in T.N. and V. aconitifolia from Rajasthan for Rhizoctonia solani seems to the new hosts for the said pathogens from these states.

• Salvaging of germplasm for disinfection against fungi and bacteria: Critical examination of germplasm and transgenics under exchange found infected with various pathogens of quarantine significance were salvaged by adopting following techniques:

a). Mechanical separation: Seeds with abnormal, deformed, shriveled, discoloured and fungal fructification Tilletia foetida (Hill bunt), Tilletia barclayana (bunt of rice), Ustilagonoidea virens (false smut of rice) etc. were salvaged by removing them mechanically followed by 95% ethyl alcohol wash.

b).Ethylalcohol wash: Exotic germplasm of Helianthus annuus found infected/ contaminated with Puccinia helianthi (sunflower rust) were salvaged by 95% ethyl alcohol wash.

c). Ethyl alcohol + sand wash: Exotic germplasm Carthamus tinctorius found infected/ contaminated with spores of P. carthami (safflower rust), Helianthus annuus  with (P. helianthi) were shaken vigorously in 95% ethyl alcohol along with a pinch of sand for one minute, then sieved and dried.

d). Acid wash: Exotic germplasm of sugar beet infected with Uromyces betae (beet rust)were salvaged by stirring in conc. Sulphuric acid for 1 min followed by washing in water and dried.

e). Chemical/ fungicidal treatment: Seed samples of exotic germplasm and transgenics found infected with various species of fungal pathogens were salvaged by fungicidal seed treatment (Bavistin 0.05% + Dithane M-45 0.2%). Cuttings and plants of horticultural crops were subjected to fungicidal dip treatment (Bavistin 0.05% + Dithane M-45 0.2%) before their release.

f). Hot water treatment (HWT): Over 80,000 samples of exotic germplasm and trial material of rice including  transgenic rice were given prophylactic hot water treatment at 52⁰C for 30 minutes against various pests. Germplasm of Brassica spp. found infected with various pests were also subjected to HWT at 50⁰C for 20 minutes.

• Inspection of crops grown in Post Entry Quarantine Nursery (P.E.Q.N.): Chemically treated germplasm and trial material of wheat, barley, triticale, other registered germplasm lines of cereals and germplasm of different species of legumes grown in PEQN at ICAR-NBPGR, New Delhi resulted in interception of loose smut in wheat (Ustilago nuda f.sp. tritici) from ICARDA (Syria), CIMMYT (Mexico), China and in registered germplasm; loose smut (Ustilago nuda) and covered smut (Ustilago hordei) in barley from ICARDA (Syria) and CIMMYT. PEQ inspection of different germplasm material grown at indenter’s site were also conducted.
• Quarantine processing of germplasm material meant for Export: Germplasm samples meant for export over the years were processed for quarantine clearance and fungi intercepted included: Ustilaginoidea virens, Alternariapadwichii and Drechslera oryzae on Oryza sativa; Colletotrichum gloeosporioides and Pestalotia sp. on leaves of Camellina sinensis; Botryodiplodia sp. and Pestalotia sp. on cuttings of grapes.
• Collection and compilation of  literature on methods for salvaging of germplasm infected with plant pathogens: Literature pertaining to crop (s), pathogen (s), treatment schedule (s) for eradication of plant pathogens (fungi, bacteria and viruses) of quarantine significance was collected, compiled and published in the form of a book entitled “Methods of Salvaging Germplasm Infected with Plant Pathogens” which will serve as a ready reckoner to the scientists, quarantine workers etc. for salvaging the infected/ contaminated germplasm under exchange.
• Preparation of check list on pests of quarantine importance to India: Cereals Grain Legumes and Edible Oil-seeds :  Information related to various fungi and bacteria with respect to their geographical distribution, host range, detection and identification of pathogens using molecular techniques, prevalence of races/ biotypes/ biovars/ strains etc. and their quarantine significance, was collected, compiled and published “Pests of quarantine importance to India: Grain Legumes”in the form of Check-list which will serve as the ready reckoner for the safe import of germplasm and in formulating the pest risk analysis.
• Collected and compiled literature on pathogen attacking a specific crop, their geographical distribution, mode of transmission, occurrence of strains/ races within a particular species etc. and published in the form of book “World distribution of phytopathogenic bacteria” which will help in assessment of risk while introducing the required germplasm.
• Preparation of Generic Pest Risk Analysis (PRA) for various crops: Country specific generic PRA was undertaken for 146 crop species for bacteria and fungi associated with the pathway for additional declarations required to be incorporated into Phytosanitary Certificate and special conditions of import as per the columns in Schedule VI of the Plant Quarantine (Regulation of import into India) Order 2003 which have already been notified by Govt. of India.
• Standard Operating Procedures developed for Ministry of Defence: Standard Operating Procedures developed for preparedness against ten pathogens that can be used as bioweapons viz., Bacterial wilt and ring rot of potato (Clavibacter michiganensis sub sp. Sepedonicus); Fire blight of apple and pear (Erwinia amylovora); Black pod of cocoa (Phytophthora megakarya); Powdery rust of coffee (Hemelia coffeicola); Sudden death of oak (Phytophthora ramorum); South American leaf blight of rubber (Microcyclus ulei); Vascular wilt of oil palm (Fusarium oxysporum f sp. Elaedis); Soybean downy mildew (Peronospora manshurica); Blue mold of tobacco (P. hyocyami sub sp. Tabacina);  Tropical rust of maize (Physopella zeae).

New records:

• Bacterial wilt (Pseudomonas solanacearum)in groundnut was recorded for the first time in India from Nagaland.
• Rapeseed, mustard & cabbage were first time recorded as new hosts for Pseudomonas solanacearum (Ralstonia solanacearum).
• Occurrence of new biotype (biotype I) of P. solanacearum in India was reported.

• Hibiscus cannabinus imported from Bangladesh found infected with Pseudomonas syringae pv. syringae and wasrecorded as a new host for it.
• Colletotrichum dematium causing anthracnose in strawberry (Fragaria X ananassa) - a new host record for India.
• Taxonomic studies were undertaken for identification of pseudomonads pathogenic to horse chestnut, wild fig & wild cherry in India and published as new pathogens.

Research work:

1. Association of two cultural types of Pseudomonas solanacearum(Ralstonia solanacearum) with bacterial wilt of sesame was reported in N.E.H. Region.
2. Mode of infection of rice seeds by Xanthomonas oryzae pv. oryzaewas investigated and reported that systemic infection in culms was detectable from base to apex or half of culm length to apex in tillers. It was found that infection in seeds was routed through the vascular system of the plant.  Seeds borne on pedicels showing vascular bacterial streaming were thus designated as ‘detectable infected seed’. This mode of infection provides sufficient amount of inoculum to seed to act as infection units in seed lots. Severe vascular infection in panicle branches resulted in chaffiness of seeds.
3. Application of Azotobacter &Pseudomonas sp. as microbial fertilizers on bacterial blight infected rice crop greatly aggravated the Kresek & bacterial blight phase of the disease more in susceptible cultivar than resistant one.
4. Method for Detection of Xanthomonas campestrispv. vignicola in cowpea seed: Of the four seed health techniques viz., seed soaking, seed maceration, blotter test and growing-on test used for the detection of X. c. pv. vignicola from naturally infected seeds of  cowpea, seed soaking test was found to be superior to other methods from quarantine point of view.
5. Alternaria alternate was reported the real cause of black point and established the differentiating symptoms of two other pathogens associated with wheat (Triticum aestivum) seeds.

Management of fungal and bacterial diseases:

a.Bacterial leaf streak disease was controlled by using double concentration of phylloplane bacteria i.e. Pseudomonas sp. than the concentration of the pathogen (X. oryzae pv. translucens)& applied 24 hr. prior to pathogen. The symptoms could not develop by applying culture filtrate also 24 hr. prior to inoculation with the pathogen.

b.Methodology for control of Colletotrichum dematium, causes anthracnose in strawberry, was developed in which four fungicides with 0.1% and 0.2% (a.i.) concentrations and one with 0.05% and 0.1% conc. were used. Fungicides Kranti (Bordeaux mixture) at 0.1% and 0.2% conc. followed by Blitox-50 WP @ 0.2% and Bavistin @ 0.1% conc. produced maximum inhibition of the pathogen.

c.Efficacy of thiram against Xanthomonas oryzae pv.oryzaeThiram fungicide was evaluated against Xanthomonas oryzae pv.oryzae and found that the fungicide effectively inhibited the growth of the bacterium at 250pp and higher concentrations. The fungicide killed the bacterium at 600, 200 and 100 ppm concentrations with 6-, 12- and 24-hr contact, respectively. The efficacy of thiram (500, 1000, 2000 ppm) plus Agrimycin-100 (250 or 500 ppm) or streptocycline (250 or 500 ppm) combinations was highly significant against the bacterium and  and suggested as dry seed treatment with thiram before sowing.

d.Field reaction of Egg plant (Solanum melongena) germplasm of 21 cultivars was evaluated against  bacterial wilt (Pseudomonas solanacearum) in Nagaland and reported that cv. BWR 54 and Pusa Purple Cluster as immune; BB1 & BWR 12 as resistant and SM 6 as moderately resistant.

e.Experiment conducted on effect of phosphorus on the yield attributes and incidence of pod blight of soybean in Nagaland and it was reported that the yield of soybean grains increased significantly up to 40 kg P/ha in absence and 20 kg P/ha in presence of FYM (10 t/ha). The application of P to soybean significantly decreased the incidence of pod blight (Colletotrichum lindemuthianum) also though it was not totally eliminated.

f.The experiment was conducted on effect of sowing date on pod blight (C.  lindemuthianum) in different varieties of soybean and reported that cultivar Bragg sown on 15 June was having less percent disease incidence of pod blight and was found to be the best cultivar and best date of sowing.

g.In experiment on fungicidal control of leaf spot (Cercospora arachidicola)and rust (Puccinia arachidis) diseases of groundnut in Nagaland reported that carbendazim (0.1% a.i.) gave maximum reduction of both tikka leaf spot and rust diseases; Copper oxy chloride (0.2 % a.i.) and mancozeb (0.2% a.i.) reduced rust only.

h.The experiment conducted with 10 different cvs. of soybean and 4 diff. dates of sowing on incidence of frog eye leaf spot (Cercospora sojina) and reported that cv. PK-472 was found to be the best cultivar which was having less disease incidence and sowing date 15^th June to be the best in comparison to others.

Recognitions & Awards

Recognition

1. Professional Recognition: “OUTSTANDING” progress work by Secretary, DARE and Director General ICAR, Krishi Bhavan, New Delhi vide his letter D.O. No. Sect.(DARE) & DG (ICAR)/A/MRP/ 2003/04 Dated the 27^th August, 2003
2. Fellow of Indian Society of Plant Genetic Resources, New Delhi in 2009.
3. Fellow of The Plant Protection association of India, Hyderabad in 2015.
4. Councillor and Executive Council Member of The Plant Protection association of India from

2014-2016

Award

Best Research Paper published

1. Smt Kavuri Sarada Memorial Award Awarded by “The Plant Protection association of India- Hyderabad” for the Best Research Paper during 2014 entitled “Kandan A, J Akhtar, B Singh, U Dev, R Goley, D Chand, A Roy, S Rajkumar and PC Agarwal (2014). Genetic diversity analysis of Alternaria alternata isolates infecting different crops using URP and ISSR markers. Indian Journal of Plant Protection 42(3), 229-236” published in the Indian Journal of Plant Protection.

Best Poster Presentation Award       

1.      Baleshwar Singh, J Akhtar, U Dev, A Kandan, D Chand and PC Agarwal (2012) “Interception of pathogenic fungi and a bacterium in introduced germplasm” for the poster under theme “Bio Safety and Quarantine” in International Conference on Plant Health Management for Food Security (ICPHM 2012) organized by Plant Protection Association of India, Hyderabad held at DDR, Rajendranagar, Hyderabad on November 28-30, 2012.

2. Kandan A, J Akhtar, B Singh, D Pal, D Chand and PC Agarwal (2014) Rapid and sensitive detection of seed-borne pathogen Colletotrichum capsici  in Capsicum annuum using Loop-mediated isothermal amplification assay. In: Book of Abstracts (Poster Papers), 6^th Indian Horticulture Congress- An International Event on Horticulture for Inclusive Growth, Tamil Nadu Agricultural University Coimbatore, Tamil Nadu, 6-9 November, 2014.
3. Best Poster Award for the poster“Pathogenic fungi not yet reported from India intercepted in imported germplasm” by J Akhtar, Baleshwar Singh, A Kandan, P Kumar Dinesh Chand and SC Dubey under Theme 16 of 6^th IPS International Conference on “Plants, Pathogens and People- Challenges in Plant Pathology to Benefit Humankind” organized by Indian Phytopathological Society at NASC Complex, New Delhi, India from February 23-27, 2016.

4.      Commendation Poster Award for the poster paper entitled “Detection of seed-borne fungi from some medicinal and aromatic crops germplasm meant for pest-free conservation at National Genebank, India” by Jameel Akhtar, Baleshwar Singh, A. Kandan, P. Kumar, V. Gupta, Monika Malik M and Dubey SC in Annual Zonal Meeting and National Symposium on Biosecurity in Food Value Chain organized by Indian Pphytopathological Society (Delhi Zone) at ICAR-NBPGR on February 20, 2016.

5.      Commendation Poster Award for the poster paper entitled “Seed health testing of rice germplasm for fungal pathogens and cross species amplification of simple sequence repeat markers among Bipolaris species” by P Kumar, Jameel Akhtar, A Kandan, Baleshwar Singh, A. Gupta, M. Malik and S. C. Dubey in Annual Zonal Meeting and National Symposium on Biosecurity in Food Value Chain organized by Indian Pphytopathological Society (Delhi Zone) at ICAR-NBPGR on February 20, 2016.