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POST HARVEST MANAGEMENT OF BANANA ANTHRACNOSE (Colletotrichum musae Berk. & Curt.) 2848
(jau,junagdh, 2019-06) Mevada Ravina R.; Dr. H. J. Kapadiya
Banana (Musa paradisiaca L.) is one of the most important fruit crops in the tropical and sub tropical regions. Banana is suffer from many post harvest diseases among them anthracnose (Colletotrichum musae Berk. & Curt.) is most widely distributed and economically important disease of banana fruits causing severe damage and huge loss in quantity and quality of fruits. Anthracnose is field as well as post harvest disease. Infection started from field but noted in fruits as latent infection. The infected banana fruits showed peel blemishes, black or brown sunken spots on fruits. The spots bears masses of light pinkish conidia and sometimes in severely infected fruits salmon coloured acervuli also appear. The pathogen was isolated by tissue isolation technique and further the culture was identified as Colletotrichum musae Berk. & Curt. Based on its cultural and morphological characters. The pathogenicity test of the fungus was proved by following Koch’s postulates. Three artificial inoculation methods were used for proving the pathogenicity, among them pin prick injury method was found more efficient then cork borer wounding and tooth brush injury methods. During the survey, maximum disease intensity was found in fruit stock of retailers (13.03%) and highest mean disease intensity (21.36%) was observed during monsoon. The study on cultural and morphological characters of C. musae indicated that it produces whitish mycelium which later turns light pinkish in colour with masses of conidia. Sometimes several black, acervulus like structure also developed on old culture plates. Conidia were hyaline, thin walled, oblong, cylindrical with round ends and oil droplet in the middle. Under in vitro evaluation of biocontrol agents, Trichoderma harzianum gave maximum growth inhibition (69.10%) of C. musae. Among the various phytoextracts, garlic clove extract gave maximum inhibition (65.28%) of test pathogen. Whereas, cinnamon oil gave maximum (74.55%) mean growth inhibition of C. musae over the rest. Looking to the efficacy of different fungicides groups, mancozeb 75% WP (non-systemic) at 1000 ppm, carbendazim 50% WP (systemic) at 50 ppm and carbendazim 12% WP + mancozeb 63% WP (combination product) at 100 ppm were found most effective and gave cent per inhibition of pathogen. Under the fruit dip treatment of all best in vitro treatments, minimum (11.54%) per cent disease intensity (PDI) was recorded in carbendazim 12% WP + mancozeb 63% WP at 0.05% concentration with minimum weight loss (9.31%) and highest shelf life (10 days). Whereas, organic control methods, essential oils, non poisonous chemicals and hot water treatment, the minimum PDI was recorded in cinnamon oils at 0.1 per cent (36.87%), calcium chloride at 4% (4.28%) and hot water treatment at 50º C for 20 min (29.18%). Total sugar and total phenol, both of these bio-chemicals were decrease as anthracnose disease progress on banana fruits. But the total sugar and total phenol content in fruits treated with various treatments were higher as compared to infected fruits.
Open Access
LEAF BLIGHT (Alternaria triticina) OF WHEAT AND ITS MANAGEMENT 2807
(JAU, JUNAGADH, 2019-06) KOMMETA MAHESH; I. B. KAPADIYA
The present research work entitled “Leaf blight (Alternaria triticina) of wheat and its management” was under taken at the Department of Plant Pathology, Junagadh Agricultural University, Junagadh during 2017-18 to 2018-19. Wheat suffers from many fungal diseases, among which Alternaria leaf blight disease caused by Alternaria triticina is one of the important disease and intensity of disease has also increased in the recent years in North India. Hence, with a view to generate scientific information under agro climatic conditions of South Saurashtra region of Gujarat conditions, present investigation was carried out during 2017-18 to 2018-19. The typical symptoms of leaf blight appeared on leaves of the infected wheat plants. The disease initially appeared in the field as small, oval, chlorotic lesions they were irregularly scattered on the leaves. These enlarge, become irregular in shape and develop into dark brown or grey sunken lesions. Some lesions showed bright-yellow marginal zone and minute black powdery conidia inside the lesions. At the dough stage of wheat development infected fields appear dull and bronzed with a burnt appearance when seen from a distance. The fungal pathogen was isolated from diseased plant on PDA and pathogenicity was proved successfully by spray inoculation method. Based on cultural and morphological characters viz., dirty white mycelium with black colour discolouration with mycelium initially hyaline, later on turn olive buff to deep olive buff colour, branched, septate at irregular interval and conidia were acrogenous borne singly or in chain of 2-7 with beak, smooth obclavate, conical, elongated, cylindrical and both ends rounded gradually tapering in to beak. Based on the size, shape and colour of conidia, the fungus was identified as Alternaria triticina. Out of 10 varieties screened under artificial condition, none of the entries were free from leaf blight. However, GW 366, GW 322, GW 496, GW 173, Raj 4238, GW 11 and Lok 1 were found resistant. The remaining three entries were moderately resistant. In laboratory screening, non-systemic fungicides viz., mancozeb 75 % WP and propineb 70 % WP were found most effective with 89.41 and 88.70 per cent fungal growth inhibition, respectively. While systemic fungicides viz., propiconazole 25 % EC and hexaconazole 5 % EC proved most effective with 96.00 and 90.33 per cent fungal growth inhibition, respectively. But in combination fungicides viz., azoxystrobin 11 % + tebuconazole 18.30 % WP, hexaconazole 4 % + zineb 68 % WP and carboxin 37.5 % + thiram 37.5 % WS were found most effective with cent per cent growth inhibition of fungus. In phytoextracts studies, Azardirachtha indica (Neem leaves extracts) was found effective with 40.06 per cent mean mycelial growth inhibition. While biological control point of view under in vitro condition Trichoderma viride gave 70.56 per cent mean mycelial growth inhibition of test pathogen. Among the different fungicides tested as foliar spray under field conditions, the lower disease intensity (15.79 %) was recorded in foliar application of propiconazole 25 % EC (500 ppm) followed by hexaconazole 4 % + zineb 68 % WP (18.44 %) at 1000 ppm. The maximum grain yield (3831 kg/ha) was also recorded in foliar spray of propiconazole 25 % EC which was at par with hexaconazole 4 % + zineb 68 % WP and hexaconazole 5 % SC.
Open Access
CHARACTERIZATION OF Fusarium udum Butler CAUSING WILT OF PIGEON PEA AND ITS MANAGEMENT 2814
(jau,junagdh, 2019-06) RAMACHANDRASINGH; Dr. L. F. AKBARI
Pigeon pea (Cajanus cajan (L.) Mill sp.) popularly known as tur or arhar, a member belonging to family Fabaceae, believed to be originated in peninsular india is one of the most essential leguminous food crop cultivated in tropical and subtropical countries. It is the second most important pulse crop after chickpea, grown in India and plays an important role in subsistence agriculture. In India, major pigeon pea growing states are Maharashtra, Madhya Pradesh, Gujarat, Karnataka, Andhra Pradesh, Uttar Pradesh, Jharkhand, Orissa, Bihar and Rajasthan. Among them, Gujarat contains 9.06 lakh ha area with 9.03 lakh tones production, which contribute about 3 per cent area and 4 per cent production among the Indian states (Annon. 2017-18). Pigeonpea subjected to many diseases, among them, wilt caused by Fusarium udum Butler is the most important one. The fungus isolated from infected plants grew as white thick cottony growth, with septate mycelia. Produced micro and macroconidia, also chlamydospores in old culture. Based on the morphological and cultural characters viz., mycelium, conidia, chlamydospores and growth characters the causal fungus of wilt in pigeonpea was identified as Fusarium udum Butler. Pathogenicity of Fusarium udum was confirmed by reproducing the same symptoms like drooping of lower leaves, yellowing of leaves, interveinal chlorosis, loss of leaf turgidity and ultimately leading to death of entire plant. The plants showed two types of wilting symptoms viz., complete wilting and partial wilting. The affected plants when longitudinally split opened showed brown to black vascular discoloration. Re-isolation confirmed the pathogenicity of Fusarium udum as the infected tissues produces the mycelia growth and conidial structures of the original fungus. Pathogenicity proved by different isolates of pathogen showed highest disease incidence in Isolate-2 which was collected from Bagdu villege (85.71 %). All the agrochemicals tested were capable of inhibiting the mycelial growth of Fusarium udum at various concentrations as compared to control under in vitro condition. Among non-systemic fungicides, copper hydroxide 53.8 % DF and copper oxychloride 50 % WP were found to be the most effective fungicides, which gave 89.24 and 77.37 per cent mean mycelial growth inhibition, respectively. Mancozeb 75 % WP was the least effective fungicide with mean mycelial growth inhibition of 55.90 per cent mean mycelial growth inhibition. Whereas in systemic fungicides, carbendazim 50 % WP and tebuconazole 25.9 % EC were found most effective in mean reduction of radial growth of mycelium with inhibition of 87.39 and 85.35 per cent, respectively. Azoxystrobin 23 % SC recorded the least mean inhibition of mycelia growth with 64.79 per cent. Among different combination fungicides tested, cymoxanil 8 % + mancozeb 64 % WP recorded cent per cent inhibition in all the tested concentrations and was found to be most effective under in vitro among all agro chemical used. In case of herbicides tested, quizalofo-p-pethyle 5 % EC proved as most effective inhibiting the mycelial growth with 76.20 mean per cent inhibition. Among the seven biological control agents, Trichoderma harzianum and Trichoderma hamatum were found most effective in inhibiting the pathogen under in vitro condition. In case of in vitro antagonism Trichoderma harzianum and Trichoderma hamatum showed 79.63 and 74.63 per cent mycelia growth inhibition, respectively. In pot culture experiment fungicide as well as bioagent are evaluated in net house. Among them, carbendazim 12 % + mancozeb 63 % WP was found most effective with least per cent disease incidence of 40 per cent. In case of bioagent Trichoderma harzianum and Trichoderma hamatum most antagonistic effect with disease incidence of 40 and 43.33 per cent, respectively
Open Access
POST HARVEST MANAGEMENT OF BANANA ANTHRACNOSE (Colletotrichum musae Berk. & Curt.) 2448
(JAU, JUNAGADH, 2019-06) MEVADA RAVINA RAMESHBHAI; H. J. Kapadiya
Banana (Musa paradisiaca L.) is one of the most important fruit crops in the tropical and sub tropical regions. Banana is suffer from many post harvest diseases among them anthracnose (Colletotrichum musae Berk. & Curt.) is most widely distributed and economically important disease of banana fruits causing severe damage and huge loss in quantity and quality of fruits. Anthracnose is field as well as post harvest disease. Infection started from field but noted in fruits as latent infection. The infected banana fruits showed peel blemishes, black or brown sunken spots on fruits. The spots bears masses of light pinkish conidia and sometimes in severely infected fruits salmon coloured acervuli also appear. The pathogen was isolated by tissue isolation technique and further the culture was identified as Colletotrichum musae Berk. & Curt. Based on its cultural and morphological characters. The pathogenicity test of the fungus was proved by following Koch’s postulates. Three artificial inoculation methods were used for proving the pathogenicity, among them pin prick injury method was found more efficient then cork borer wounding and tooth brush injury methods. During the survey, maximum disease intensity was found in fruit stock of retailers (13.03%) and highest mean disease intensity (21.36%) was observed during monsoon. The study on cultural and morphological characters of C. musae indicated that it produces whitish mycelium which later turns light pinkish in colour with masses of conidia. Sometimes several black, acervulus like structure also developed on old culture plates. Conidia were hyaline, thin walled, oblong, cylindrical with round ends and oil droplet in the middle. Under in vitro evaluation of biocontrol agents, Trichoderma harzianum gave maximum growth inhibition (69.10%) of C. musae. Among the various phytoextracts, garlic clove extract gave maximum inhibition (65.28%) of test pathogen. Whereas, cinnamon oil gave maximum (74.55%) mean growth inhibition of C. musae over the rest. Looking to the efficacy of different fungicides groups, mancozeb 75% WP (non-systemic) at 1000 ppm, carbendazim 50% WP (systemic) at 50 ppm and carbendazim 12% WP + mancozeb 63% WP (combination product) at 100 ppm were found most effective and gave cent per inhibition of pathogen. Under the fruit dip treatment of all best in vitro treatments, minimum (11.54%) per cent disease intensity (PDI) was recorded in carbendazim 12% WP + mancozeb 63% WP at 0.05% concentration with minimum weight loss (9.31%) and highest shelf life (10 days). Whereas, organic control methods, essential oils, non poisonous chemicals and hot water treatment, the minimum PDI was recorded in cinnamon oils at 0.1 per cent (36.87%), calcium chloride at 4% (4.28%) and hot water treatment at 50º C for 20 min (29.18%). Total sugar and total phenol, both of these bio-chemicals were decrease as anthracnose disease progress on banana fruits. But the total sugar and total phenol content in fruits treated with various treatments were higher as compared to infected fruits.
Open Access
CHARACTERIZATION OF Fusarium udum Butler CAUSING WILT OF PIGEON PEA AND ITS MANAGEMENT
(JAU, JUNAGADH, 2019-06) RAMACHANDRASINGH; Dr. L. F. AKBARI “
Pigeon pea (Cajanus cajan (L.) Mill sp.) popularly known as tur or arhar, a member belonging to family Fabaceae, believed to be originated in peninsular india is one of the most essential leguminous food crop cultivated in tropical and subtropical countries. It is the second most important pulse crop after chickpea, grown in India and plays an important role in subsistence agriculture. In India, major pigeon pea growing states are Maharashtra, Madhya Pradesh, Gujarat, Karnataka, Andhra Pradesh, Uttar Pradesh, Jharkhand, Orissa, Bihar and Rajasthan. Among them, Gujarat contains 9.06 lakh ha area with 9.03 lakh tones production, which contribute about 3 per cent area and 4 per cent production among the Indian states (Annon. 2017-18). Pigeonpea subjected to many diseases, among them, wilt caused by Fusarium udum Butler is the most important one. The fungus isolated from infected plants grew as white thick cottony growth, with septate mycelia. Produced micro and macroconidia, also chlamydospores in old culture. Based on the morphological and cultural characters viz., mycelium, conidia, chlamydospores and growth characters the causal fungus of wilt in pigeonpea was identified as Fusarium udum Butler. Pathogenicity of Fusarium udum was confirmed by reproducing the same symptoms like drooping of lower leaves, yellowing of leaves, interveinal chlorosis, loss of leaf turgidity and ultimately leading to death of entire plant. The plants showed two types of wilting symptoms viz., complete wilting and partial wilting. The affected plants when longitudinally split opened showed brown to black vascular discoloration. Re-isolation confirmed the pathogenicity of Fusarium udum as the infected tissues produces the mycelia growth and conidial structures of the original fungus. Pathogenicity proved by different isolates of pathogen showed highest disease incidence in Isolate-2 which was collected from Bagdu villege (85.71 %). All the agrochemicals tested were capable of inhibiting the mycelial growth of Fusarium udum at various concentrations as compared to control under in vitro condition. Among non-systemic fungicides, copper hydroxide 53.8 % DF and copper oxychloride 50 % WP were found to be the most effective fungicides, which gave 89.24 and 77.37 per cent mean mycelial growth inhibition, respectively. Mancozeb 75 % WP was the least effective fungicide with mean mycelial growth inhibition of 55.90 per cent mean mycelial growth inhibition. Whereas in systemic fungicides, carbendazim 50 % WP and tebuconazole 25.9 % EC were found most effective in mean reduction of radial growth of mycelium with inhibition of 87.39 and 85.35 per cent, respectively. Azoxystrobin 23 % SC recorded the least mean inhibition of mycelia growth with 64.79 per cent. Among different combination fungicides tested, cymoxanil 8 % + mancozeb 64 % WP recorded cent per cent inhibition in all the tested concentrations and was found to be most effective under in vitro among all agro chemical used. In case of herbicides tested, quizalofo-p-pethyle 5 % EC proved as most effective inhibiting the mycelial growth with 76.20 mean per cent inhibition. Among the seven biological control agents, Trichoderma harzianum and Trichoderma hamatum were found most effective in inhibiting the pathogen under in vitro condition. In case of in vitro antagonism Trichoderma harzianum and Trichoderma hamatum showed 79.63 and 74.63 per cent mycelia growth inhibition, respectively. In pot culture experiment fungicide as well as bioagent are evaluated in net house. Among them, carbendazim 12 % + mancozeb 63 % WP was found most effective with least per cent disease incidence of 40 per cent. In case of bioagent Trichoderma harzianum and Trichoderma hamatum most antagonistic effect with disease incidence of 40 and 43.33 per cent, respectively.
Open Access
PHENOTYPIC STABILITY FOR GRAIN YIELD AND ITS CONTRIBUTING CHARACTERS USING DIFFERENT STABILITY MODELS IN BREAD WHEAT (Triticum aestivum L. em. Thell.)1979
(JAU,JUNAGADH, 2015-04) ODEDRA RAMA KANA; M.S. Pithiya
The genotype x environment interaction is of major concern in plant breeding programmes. Number of statistical methods have been developed to analyse G x E interaction and thereby to evaluate pbenotypic stability of genotypes. However, the literature on comparison of stability analysis model is very scanty. The present study was undertaken to compare some stability analysis models. For this purpose eighty genotype of bread wheat were evaluated at two different locations viz., Wheat Research Station and Krishi Vigyan Kendra, Khapat (Porbandar), Junagadh Agricultural University, Junagadh during the Rabi 2009-10 in a randomized complete block design with three replication. Four environments were created by sowing crop in two different dates of sowing at two locations i.e. Ei (normal sowing at Khapat), E2 (late sowing at Khapat), E3 (normal sowing at Junagadh), E4 (late sowing at Junagadh). The data on days to 50% flowering, days to maturity, plant height (cm), number of effective tillers per plant, peduncle length (cm), flag leaf area (cm^), length of main spike (cm), number of spikelets per spike, number of grains per spike, 1000-grain weight (g)» biological yield per plant (g), harvest index (%) and grain yield per plant (g) were recorded and analysed. Three stability analysis models proposed by Eberhart and Russell (1966), Perkins and Jinks (1968) and Freeman and Perkins (1971) were compared empirically for their efficiency. Additive main effects and multiplicative interaction (AMMI) analysis was also attempted in this study to evaluate 80 bread wheat genotypes established in four environments using grain yield data in order to determine the magnitude of G x E interaction and to identify stable and adaptable genotypes. Differential relative response to different genotypes to different enviromnents were observed for grain yield and other characters under study. The ranking of genotypes for grain yield per plant showed that none of the genotype had same rank in all the environments. The genotype MACS 2496, GW 322
Open Access
DISEASE DEVELOPMENT AND MANAGEMENT OF LEAF BLIGHT [Stemphylium vesicarium (Wallr.) E. Simmons] OF GARLIC {Allium sativum L.) 1974
(JAU, JUNAGADH, 2015-01) KAPADIYAITESHKUMAR B; Dr. C. LUKOSE
Garlic {Allium sativum L.) belonging to the family Alliaceae is the second most important bulb crop grown throughout the plains of India for spices and condiments. Though, garlic is seriously affected by many diseases, leaf blight caused by Stemphylium vesicarium (Wallr.) E. Simmons is an important destructive disease. It appears every year in a moderate to severe form in garlic growing areas of Saurashtra region of Gujarat. The causative organism isolated from the infected leaves of the diseased plants of garlic grew in the form as dark green to blackish mycelium, which later turned olivaceous brown to black and finally velvety on PDA. Conidia were light brown or golden brown to olive brown, oblong or broadly oval, producing on straight to variously curved cylindrical and septate conidiophores. Based on the morphological characters viz., mycelium, conidiophores, conidia and growth patterns, the causative fungus isolated from the leaves of infected garlic plant was identified as Stemphylium vesicarium (Wallr.) E. Simmons. Garlic plants were susceptible to leaf blight from 30 to 35 days of growth, but it was more prominent at 50 days onwards. Initially the infected plants exhibited characteristic symptoms of white flecks that enlarged and produced sunken purple lesions which were surrounded by a yellow to pale brown border. Later, small light yellow to brown, water soaked and non-delineated lesions developed on older leaves. Finally, these lesions grew into elongated spots that frequently coalesced resulting in blighting of leaves. The pathogenicity of S. vesicarium was confirmed by reproducing the same field symptoms like discolouration and withering of the leaves. Re-isolations confirmed the pathogenicity of S. vesicarium as the infected tissues produced the same type of mycelial growth, conidiophores and conidia of the original fungus.
Open Access
MANAGEMENT OF POWDERY MILDEW DISEASE {Erysiphe cruciferarum Opiz ex. Junell) OF MUSTARD [Brassica juncea (L.) Czern. & Coss.] 1692
(JAU,JUNAGADH, 2012-07) K. K. Kanzaria; Dr. 1. U. Dhruj
Indian mustard (Brassica juncea (L.) Czern. & Coss.) is the most important oilseed crop of India. Like other crops, rapeseed and mustard are attacked by a number of fungal, bacterial and virus diseases, which are considered economically important. Among them, powdery mildew caused by Erysiphe cruciferarum Opiz ex. Junell is an important disease particularly in the Saurashtra region of Gujarat. Hence, present investigation was carried out to assess losses due to this disease and to develop feasible management options. The initial symptoms of powdery mildew disease appeared with minute visible and almost circular fungal colony on upper surface of lower most leaf and progressed towards upper leaves on both the surfaces, stems, branches and siliquaes. Eventually whole plant covered with white powdery fungal growth showing a dusty appearance. In advanced stage, purple blue patches were seen on the stems. Heavily infected leaves turned pale yellow, dried and shedded. Infected siliquae produced shriveled seeds. Heavily infected plant showed early maturity. a-s>s7xacT The conidiophores were erect, stout and ellipsoid to cylindrical in shape and measured 67.4 + 6.2 pm with a moderately straight foot cell bearing 2-3 conidia in chain. Conidia were unicellular, hyaline, elliptical to cylindrical in shape and measured 26.5-39.8 pm x 12.4-16.6 pm in size without fibrosin bodies. Estimation of seed yield, oil, protein and test weight loss due to E. cruciferarum was 22.50, 7.26, 21.74 and 21.52 per cent, respectively when no control measures were adopted. The avoidable yield loss 23.48 per cent and net profit of Rs.9,390 per hectare was achieved by spraying the crop with hexaconazole @ 0.005 per cent. Screening of 13 entries against powdery mildew in vivo showed that the entries GM-2 was highly susceptible, while GM- 1 and GM-3 showed susceptible reaction. The entries HNS-0004, lSN-129 and NUDB-26-11 were moderately susceptible and GSL- 1 and GSL-861-212 exhibited resistant reaction. DLSC-3, Kiran, NPC-3, NPC-111 and NPJ-87 exhibited highly resistant reaction. The effect of maximum air temperature on disease development exhibited positive and significant relationship with per cent disease intensity (PDI) while minimum air temperature with PDI was found non significant. The morning relative humidity was significantly negatively correlated with PDI and afternoon relative humidity was highly negatively significant In multiple regression analysis, maximum temperature (°C) and afternoon relative humidity were highly significant to disease development. In laboratory screening of systemic fungicides, non systemic fungicides, insecticides and phytoextracts, as'STKMr hexaconazole, dinocap, methyl-o-demeton and clove extract of garlic [Allium sativum) were found better with 84.10, 79.98, 54.97 and 74.08 per cent inhibition of spore germination, respectively. In field evaluation of different fungicides, the minimum per cent disease intensity (PDI) 28.17 and a maximum yield of 2225 kg/ha was recorded in the treatment of hexaconazole with 54.17 per cent disease control and 30.04 per cent yield increase. The highest incremental cost benefit ratio (ICBR) of 1:4.63 was obtained in four sprays of hexaconazole 0.005 per cent followed by wettable sulphur 0.2 per cent (1:3.36) and penconazole 0.010 per cent (1:1.07). The maximum oil (34.37%), protein (18.05%) and test weight (5.39 g) was also recorded in the treatment of hexaconazole (0.005%). Similarly, oil, protein and test weight increase were 11.95, 26.05 and 22.78 per cent, respectively. Neem leaf extract proved to be the most effective biopesticide and recorded 38.35 PDI with 44.20 per cent disease control and 2013 kg/ha seed yield with 21.41 per cent yield increase. The highest ICBR of 1:5.19 was found in four sprays of neem leaf extract and followed by neem seed kernel extract (1:3.72) and azadirachtin (1:1.08). The maximum per cent oil (33.97), protein (16.69) and test weight (5.38 g) and per cent increase in oil (9.97), protein (15.34) and test weight (23.68) were recorded in neem leaf extract treatment under field conditions.
Open Access
CHARACTERIZATION OF Fusarium oxysporum f. sp. vasinfectum [(Atk.) Snyder & Hansen] CAUSING WILT OF COTTON AND ITS MANAGEMENT
(JAU,JUNAGADH, 2018-06) A. B. VIRANI; Dr. V. V. RAJANI
Cotton (Gossypium spp.) is an important fiber cash crop, which was found to be suffering from Fusarium wilt disease in moderate form in Saurashtra region of Gujarat state. Cotton plant showing typical wilt symptoms in pot and field conditions. Leaves turned yellow and lose its turgidity. Collar region of plant was dry and turned to brown. When roots of such infected plants were spilt vertically from collar region to downwards, the vascular system showed brownish discoloration. The repeated isolation from infected plants revealed the association of Fusarium oxysporum f. sp. vasinfectum. On the basis of morphological, cultural, molecular characters and pathogenicity test it identified as Fusarium oxysporum f. sp. vasinfectum. The pathogenicity was successfully proved by soil inoculation method. Biochemical study revealed that total phenol and peroxidase enzyme were higher in disease infected plant parts (leaf and root) comparison to healthy plant parts. In laboratory screening of different agro-chemicals, tebuconazole 25.9 EC was found to be quite effective in inhibiting the radial growth of test pathogen among systemic group of fungicides, while in non-systemic group of fungicides, copper oxychloride 50 WP and in case of fungicide combinations tebuconazole 50 + Abstract trifloxystrobin 25 WP were significantly inhibited the growth of test fungus under in vitro. Among the fungal and bacterial antagonists, T. harzianum was most effective in growth inhibition of test fungus. Next best was T. viride followed by B. subtilis, T. koningii, T. atroviride and P. fluorescences. Among nine phytoextracts of indigenous plants were evaluated in vitro against test pathogen using poisoned food technique, maximum inhibition was recorded in garlic cloves extract (72.15%), followed by neem leaves extract (65.34%). Effective antagonists and fungicides were tested in net house condition in pot culture. Among two antagonists and six fungicides tested, the combination of carboxin 37.5 + thiram 37.5 WP showed minimum plant disease incidence (PDI) followed by carbendazim 50 WP. .

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