Browsing by Author "Sulochana, K K"

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Disease management and growth improvement in chilli and tomato using Trichoderma Spp. and flurascent pseudomonads
(Department of Plant Pathology, College of Agriculture, Vellayani, 2005) Rini, C R; Sulochana, K K
Evaluation of fluorescent pseudomonads for the management of sheath rot of rice
(Department of Plant Pathology, College of Agriculture, Vellayani, 2004) Sundaramoorthy, M; Sulochana, K K
The study entitled ‘Evaluation of fluorescent pseudomonads for the management of sheath rot of rice’ was carried out at three stages i.e., under in vitro condition, green house condition, and field conditions. First two were conducted at the college of Agriculture, Vellayani, and the third one was conducted at CSRC, Karamana. The pathogen Sarocladium oryzae was isolated from the sheath portion of naturally infected rice plants and its identity was confirmed based on the cultural and morphological studies. Twenty different isolates of fluorescent pseudomonads were isolated from, rhizosphere and phyllosphere of healthy rice plants collected from various locations of southern Kerala. They were screened against Sarocladium oryzae under laboratory condition following duel culture technique. Based on the inhibition zone formation six best isolates were selected. In green house studies, six selected isolates were made into a talc based formulation and applied as seed treatment, seedling root dip and foliar spray. Here, the isolate Pf 16 performed well over other isolates and proceeded further for study under field condition. In the field, powder based formulation of selected isolate Pf16 in three different methods of application viz., seed treatment (ST), seedling root dip (SRD) and foliar spray (FS) in nine combinations were applied. Among the different combinations tried combined application of seed treatment + seedling root dip + foliar spray (ST+SRD+FS) gave considerable reduction in disease incidence and improved biomass yield. Based on the preliminary biochemical studies conducted the isolates Pf16, Pf19 and Pf8 were tentatively identified as Pseudomonas fluorescens biovar II, Pseudomonas aeruginosa, Pseudomonas fluorescens biovar I respectively. The metabolite of promising isolate Pf16 extracted and it formed a clear inhibition zone around the pathogen when antagonism was done.
Fungal diseases of sesamum in Kerala
(Department of Plant Pathology, College of Agriculture, Vellayani, 1989) Sulochana, K K; Balakrishnan, S
Only limited information is currently available on the fungal diseases of sesamum in Kerala. During the course of the present study 12 fungal diseases could be identified and among these, leaf spots caused by Botryodiplodia theobromae and Pestalotia sp. are new records. Investigations were carried out to find out the losses caused by the major fungal pathogens, viz., Alternaria sesami, Colletotrichum gloeosporioides, Curvularia lunata, Botryodiplodia and Fusarium oxysporum f. sp. sesami. Loss estimation studies conducted revealed that all the above fungi reduced the yield considerably. Rhizopus nigricans, Aspergillus flavus, A. niger and Mucor haemali were the common fungi found associated with sesamum seeds. Mode of entry, histopathology and toxin studies were conducted with the five major fungal pathogens. These varied with different organisms. Survival ability of the five species of fungi ranged from three months in A. sesami to elevan months in B. theobromae and F. oxysporum f. sp. sesami. In vitro evaluation of fungicides, in general, revealed that, Bavistin, Bordeaus mixture and Dithane M-45 were superior to the other fungicides tested, and in the field experiment Bavistin was found to be the best. The residue levels of carbendazim of Bavistin sprayed sesamum leaves and pods were below the maximum residue level fixed. Application of fungicides caused alterations in the acid value, iodine value and saponification value of sesamum oil. Bavistin was found to be the most efficient as well as economical fungicide in controlling the leaf spot diseases of sesamum. Varietal screening trials showed Si. 866, Kayamkulam-2, Si.44, Trivandrum local and North Kerala local No.24 as resistant/tolerant varieties against the five species of fungi.
Fungicidal control of fruit rot of chilli caused by colletotrichum capsici (Syd.) Butl. & Bisby
(Kerala Agricultural University, 1992) Sulochana, K K; Rajagopalan, B; Wilson, K I
Growth of cylindrocladium quinqueseptajum on different oil incorporated medfa
(Kerala Agricultural University, 1983) Sulochana, K K; Wilson, K I; Chandrasekharan Nair, M
Leaf blight of banana and its control
(Department of Plant Pathology, College of Agriculture, Vellayani, 1993) Saj, K V; Sulochana, K K
Management of phomopsis blight and fruit rot of brinjal (Solanum Melongena L.)
(Department of Plant Pathology, College of Agriculture, Vellayani, 2011) Lakshmi Nair, P; Sulochana, K K
Seed borne mycoflora of sesame (Sesamum indicum L.)
(Kerala Agricultural University, 1997) Sulochana, K K; Balakrishnan, S
Some new host records for Cylindrocladium Quinqueseptatum from India
(Kerala Agricultural University, 1982) Sulochana, K K; Wilson, K I; Chandrasekharan Nair, M
Studies on the leaf blight disease of clove caused by Cylindrocladium sp.
(Department of Plant Pathology, College of Agriculture, Vellayani, 1980) Sulochana, K K; Chandrasekharan Nair, N
Leaf blight disease of clove caused by Cylindrocladium cuinqueseptatum Boedijn et Roitsma was investigated. The fungus infected clove leaves at all stages of maturity, but the seedlings were found to be more susceptible to the disease than mature plants. Injury of the host tissue was found to be a pre-requisite for successful infection by the fungus. The organism infected a wide variety of plants including some of the weed plants on artificial inoculation. Good growth and sporulation of the fungus was obtained on potato dextrose agar followed by Coon’s agar and Czapek’s agar. In liquid media, maximum dry weight of the mycelium was obtained on potato media, maximum dry weight of the mycelium was obtained on potato dextrose broth, followed by Czapeks’ broth. Maximum growth of the fungus was obtained on medium amended with gingelly oil followed by coconut and clove oils. In liquid media, maximum dry weight of the mycelium was obtained in the medium amended with gingelly oil followed by coconut clove oils. Optimum pH range for the growth of the fungus was found to be 7 to 9. Richards’ broth was found to be the best medium for the production of toxin followed by Czapek’s and Fries’ media. Exotoxin production was found to be more than endotoxin. The toxic metabolite is found to be thermostable. Diluting the culture filtrate to 4 times its volume showed a reduction in the toxic effect. However, the treatments did not completely eliminated the toxic effect of the preparation. The toxic effect of the culture filtrate translocated by defoliation on the cut twigs of plants. Culture filtrate of the fungus inhibited the spore germination of Colletotrichum glocosporioides and Curvularia sp. The culture filtrate as well as the mycelial extract produced lesions on clove leaves of different maturity, with pronounced effect on tender leaves. Spore germination of the fungus could be completely inhibited with all the eight fungicides in all concentrations on the first day of observation. Daconil-2767, Dithane M-45, Fytolan and Thride were able to cause 94,97,94 and 95 per cent inhibition of spore germination respectively upto 12th day at maxium concentration tested ( 3000 ppm). Growth of the fungus was completely inhibited with Bavistin 250, 500 and 1000 ppm, Dithane M-45 1000, 2000 and 3000 ppm; Mildothane 500, 1000 and 2000 ppm and thride 1000, 2000 and 3000 ppm; when tested in czapeks’ agar medium. In czapeks’ solution Bavistin, Difolatan, Dithane M-45 and Mildothane at all concentrations tested, there was complete inhibition of growth of the fungus. Bavistin at 250 ppm and Thiride at 1000 ppm were able to inhibit the growth of the fungus by 15 minutes immersion, when the culture dises were tested for the viability of the fungus, Mildothene and Dithane M-45 inhibited the growth of the fungus at 1000 and 2000 ppm respectively, When the culture discs were tested for the viability of the fungus after immersion for one hour in fungicidal solution. Fytolan and Difolaton were able to inhibit the growth of the fungus at the maximum concentration (both at 3000 ppm), only after 24 hours immersion in the fungicidal solution.