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Open Access
Management of Major Diseases of Bell Pepper (Capsicum Frutescens L. )
(Birsa Agricultural University, Ranchi, 2002) Jhabbu rai; N. Kudada
Bell pepper (Capsicum frutescens L.) is most important cash crop grown in Jharkhand state. Survey carried out during rabi, 2000-2001 and kharif, 2001 cropping seasons showed leaf spot, fruit rot, wilt and leaf curl to be major diseases of bell pepper, prevalent in different localities of Chotanagpur with varying intensities. The intensity/incidence of the above mentioned diseases were higher during kharif season as compared to rabi season. The conidiophores of the fungus responsible for leaf spot disease of bell pepper were sparingly branched and measured 30.0-60 micron x 4.5-5.5 micron with mean size of 45.5 x 5.0 micron in size. Conidia were to be acicular to obclavate and measured 75-125 micron x 4-5 micron with a mean of 98.5 x 4.5 micron in size. Stromata were well developed and fruiting was Amphigenous. The organism was identified as Cercospora capsici. The acervuli of the fungus causing fruit rot were small, hemispherical in shape and dark brown in colour, measured from 57-100 micron in diameter alongwith setae, condiophore, conidia and mycelium. The setae were dark brown having light brown tips, needle shaped, septate and abundant in number. Their size varied from 67.5-152.0 micron x 1.5-3.5 micron. The conidiophore were small, unbranched, erect and arose from acervulus in masses and measured 13.0-22.50 micron x 2.5-4.0 micron. The conidia were borne singly at the tips of conidiophores, unicellular, hyaline, curved with narrow ends and the size varied from 16.0-27.50 micron x 1.5-3.0 micron. The mycelium was septate, branched, hyaline, inter and intracellular. Based on morphological characters, the causal fungus was identified as Colletotrichum capsici.
Open Access
Prevalence and Management of Alternaria Blight of Linseed
(Birsa Agricultural University, Ranchi, 2024) Ajay Kumar; M. K. Barnwal
Alternaria blight caused by Alternaria lini is an important disease of linseed and causes severe losses in most linseed growing environments of Jharkhand. The pathogen generally produces necrotic lesions on the leaves and rarely on stems and pods of linseed plants. The initial symptom of the disease appeared on lower leaves as minute dark brown and black target like lesion on the leaves. Later the spots coalesce and covers the large area of the leaves. The affected leaves ultimately get dried up and curled. The morphological characters of the isolated fungus is as follows. The mycelium growth on PDA as white greyish at the margin with clear light to dark green zonation radiating from common center. Dark brown conidia in chains were observed ranging in sizes from 46-49 μm in length and 2.0 to 6.0 μm in width. The Conidia are dark, cylindrical to oblong, muriform without beak. The transverse septa ranged from 2-6 and vertical septa ranged from 1-3. Crops sown on 4th November recorded lowest per cent disease severity of 13.2 per cent. The crop sown on the above date also recorded highest grain yield of 1052.31 Kg/ ha. Per cent disease index (PDI) were significantly positively correlated with minimum temperature and evening relative humidity Whereas Maximum temperature, mean temperature and wind speed showed non-significantly positive correlated with PDI. PDI was significantly negative correlation with morning relative humidity, mean relative humidity and sunshine hours and grain yield. In-vitro evaluation of fungicides for control of pathogen showed that the fungicides (T7), Pyraclostrobin plus Metiram (0.1%) recorded lowest colony diameter of 12.0 mm and colony growth inhibition over control of 86.62 per cent, followed by Mancozeb (0.2%) which recorded colony diameter of 13.3 mm and colony growth inhibition over control of 85.17 per cent. The control plates showed colony diameter of 89.7 mm. In-vivo evaluation of fungicides for control of Alternaria blight of linseed envisaged that lowest per cent disease index of 8.5 per cent was recorded when two sprays of Metiram plus Pyraclostrobin (0.1%) was given. This treatment also recorded highest grain yield of 731.50 Kg/ ha and increase in grain yield over control of 32.8 per cent. When cost benefit ratio was taken into consideration then highest B:C ratio (2.60) was recorded in treatment (T4) i.e., two sprays of Mancozeb followed by two sprays of Mancozeb plus Carbendazim (1.63). when net return was taken into consideration then Highest net return was recorded when two sprays of Mancozeb (0.2%) was given which recorded a net return of Rs. 8738.8 followed by two sprays of Metiram plus Pyraclostrobin (Rs. 7539.9). In management of Alternaria blight of linseed through plant defense inducers showed that Lowest percent disease index of 8.6 per cent was recorded when seed treatment (ST) with Salicylic acid (SA) @ 50 ppm plus two foliar spray of SA @ 50 ppm at 30 days and 45 days after sowing (DAS) was given. This treatment also recorded highest grain yield of 787.04 Kg/ ha and increase in grain yield over control of 39.3 per cent. Linseed varietal screening against Alternaria blight of linseed, out of 23 entries. Six promising entries viz., Rashmi, RLC 164, RLC 92, Divya, RLC 155 and LMS 2016-1-5 showed resistant reaction against Alternaria blight of linseed under artificial epiphytotics.
Open Access
Studies on Oyster Mushroom ( Pleurotus Spp) in Plateau Region Bihar
(Birsa Agricultural University, Ranchi, 1997) Santosh Kumar Das; S.C. Dubey
The Oyster mushroom (Pleurotus spp.) has a great scope for its cultivation in the Chotanagpur and Santhal Parganas region of Bihar. The results of the experiments conducted on various aspects of its cultivation are summarized briefly as under. In order to evaluate a good source of substrate for quality spawn production, jowar grain was found as best spawn substrate followed by wheat grain in respect of colour, texture of myceium and yield, though highest number of sporophores recorded by the use of ragi grain based spawn. Amongst the four species of Pleurotus, superiority of P. flabellatus was observed as compared to other species. Spawn raised on paddy straw mixed with wheat and rice bran though required less time for spawn run but gave poor yield.. Storage of spawn in room and refrigerator showed different effect on mushroom production. Spawn stored upto 50 days at room temperature and upto 70 days in refrigerator yielded mushroom. In general storage durations reduced the quality of spawn. Fresh spawn was found to be superior in respect of number of flushes, sporophores and yield of P. flabellatus followed by
Open Access
Studies on Fusarium Wilt of Lentil (Lens Culinaris Medic ) in Chotanagpur Plateau Region of Bihar
(Birsa Agricultural University, Ranchi, 1994) D. K. Jha; D. K. Jha
Wilt of lentil (Lens culinaris Medic) caused by Fusarium oxysporum f. sp. lentis is present in almost all the lentil growing areas of Chotanagpur region of Bihar which varied between 5.2 to 37.6 per cent. The pathogen is mainly soil-borne and attack the plants at any stage of its growth. The disease development was faster and more in injured root than in the uninjured one. Koch's postulate tests were also satisfied in the present finding. The fungus produces three types of spores viz; micro & macro-conidia as also chlamydospores in culture. Macroconidia were rarely found on the upper surface of the wilted plants. However, it was quite prevalent in the inner side of the tissues. In cultural studies, Richards' medium proved to be the best, both in solid and liquid states, for the excellent growth and sporulation of the pathogen. The optimum pH recorded to be 5.3 for its growth and 5.3 to 6.3 for sporulation. The fungus could utilize all the carbon compounds tried but Mannitol proved to be the best. Out of 48 varieties/lines screened, three varieties Viz; BR 25, Pant. L- 234 and Pant. L - 639 were found to be the immune to wilt disease in plateau region of Bihar.. Thiram + Bavistin proved to be the most suitable fungicides which completely controlled the growth of pathogen in vitro and increased the germination of seeds in vivo. It was also effective in suppressing the mortality percentage of lentil plants. Organic amendments with wheat straw, with or without addition of inorganic nitrogen were effective in controlling the disease. Effect of natural soils and fresh cattle manures were found to be effective in wilt disease of lentil plant
Open Access
Studies on Banded Blight of Rice (Oryza Satival) Caused By Jhanatephorus Cucumeris (Frank) Donk in Chotanagpur
(Birsa Agricultural University, Ranchi, 1994) Ranthu Toppo; Dr. S. C. Dubey
Rice (Oryza sativa L.) suffers fron "banded blight" a very caused by Thanatephorus cucumeris (Frank) destructive disease cau Donk (=Rhizoctonia solani kühn). The characteristic symptoms of the disease was observed on leaf sheath, leaf blade, stem, panicle and spikelets. The pathogen was isolated, purified and identified by standard method. The pathogen also satisfied Koch's Postulate tests. Potato dextrose agar (solid) and Kirchoff's (liquid ) media supported maximum mycelial growth and sclerotial production. pH 6.5 was found to be optimum for mycelial growth and sclerotial production in Kirchoff's liquid medium. The pathogen was found to penetrate the host by means of infection cushion and stomatal openings. All 34 plant species belonging to 7 families were infected during host range studies.45 days old plant were highly susceptible and showed maximum intensity (64.7%) with minimum yield followed by 38 and 60 days old plants. Older plants were resistant to infection Early sowing minimized the disease development and gave good yield. Temperature, humidity and rainfall occurred during July 1st to August 1st were suitable for the maximum disease development. Out of 23 rice varieties / lines non was found to be resistant against the pathogen. However, BR-9, BR-10, BR-34, IR-36, IR-50, Pankaj and RAU-4845-10 showed moderately resistant reaction. Among different fungitoxicants tested Contaf (0.1%), Bavistin (0.1%) Bavistin (0.05 %) + Indofil M-45 (0.125%), Kitazin (0.1%) and Blitox-50 (0.2%) completely inhibited the growth of the pathogen in vitro. Bavistin (0.1%) and Topsin - (0.1%) treated rice seeds gave maximum germination 96.3% and 95.3% and elimination of seed borne infection 97.8% and 94.8%, respectively. Three spray of Contaf (0.1%) and Bavistin (0.1%) in the field condition gave the best control of the disease along with highest yield. These two fungicides also gave maximum per rupee return ie. Rs. 7.6 and Rs. 3.5, respectively. Next economically best fungicide was Bavistin + Indofil M-45 followed by Topsin -H + Indofil M-45. In bio-control through fungal antagonists, Gliocladium virens showed maximum inhibition of mycelial growth and sclerotial production of the pathogen followed by Trichoderma harzianum and Trichoderma viride. Nature of mycoparasitism was established in detailed. Among different plant extracts, Munga roots extract showed maximum inhibition of mycelial growth (55.2%) followed by Pipel (48.2%) and Bhangria (44.9%) leaf extracts. All the plant extracts checked the sclerotial formation completely. except Pipel' and Bhangria leaf extracts in which only a few sclerotia were formed. Among oil cakes tasted, Til cake inhibited maximum mycelial growth (86.3%) followed by Karanj' cake (83.3%) and *Neem* cake (81.9%). Sclerotial production was completely inhibited in all the cakes used.
Open Access
Epidemiology And Control of Brown Leaf Spot (Drechlera Oryzae) of Paddy Under Upland Condition
(Birsa Agricultural University, Ranchi, 1994) R.K. Samarjit Singh; B. Mishra
(0.055 per cent day-1) and severity (0.036 per cent day-¹) were recorded during September month. The disease incidence and severity were (+)vely correlated with temperature (0.885 and respectively), 0.8374, relative humidity (0.7888 and 0.7889, respectively), and rainfall (0.7996 and 0.8313, respectively) but, (-)vely with sunshine hours (-0.3287 and -0.6968, respectively). The optimum levels of N, P and K with respect to disease suppression and maximum grain yield, were observed to be 100, 60 and 40 kg h -1 respectively. Disease incidence and severity showed highly significant (+)ve correlation, but, both of them showed (-) ve correlation with grain yield. The loss in grain yield ranging from 45.51 per cent to per cent were observed while assessing three rice 56.20 cultivars for their loss in grain yield due to brown leaf spot disease under upland field conditions. Of the 71 different cultivars screened against D. oryzae under both natural and artificially inoculated conditions, 7 varietiesviz IR-12-9-4, Mutant-7, Ratna x RAU 40.45-3-17, BR 8 Mutant, BR 8 Mutant (Ma) Kr and IR 18348-36-3-3 and OR 164-5 (IED 7252) were found to be resistant, 44 moderately resistant and 20 moderately susceptible. Five sprays of crude extract (10 per cent) of Impatiens balsamina or Solanum nigrum at an interval of 15 days gave satisfactory control of the disease. In biological control, three sprays of Bacillus megaterium at a concentration of 10000 cells m1-1, 48 hours ahead of pathogen's inoculation and at an interval of 20 days could control the disease under upland conditions. The best control was achieved with three sprays of Kitazin (0.1 per cent) followed by that of Salvistin (Carbendazim). Maximum economic turn-over of Rs 4.12 from an investment of Rs 1.00 was obtained from spraying Kitazin (0.1 per cent) thrice during fungicidal control of the brown leaf spot disease of rice.
Open Access
OCCURRENCE AND MANAGEMENT OF MAJOR DISEASES OF CHICKPEA (Cicer arietinum L.)
(Birsa Agricultural University, Ranchi, 2022) Sushil Kumar Singh; Savita Ekka
Collar rot, Alternaria blight and Fusarium wilt are the major production constraints that severely affect chickpea production. A thorough study was carried out to find the occurrence and distribution of diseases of chickpea and its management through host plant resistance, fungicides, bio agents and soil amendments. Extensive survey were carried out in 5 major chickpea growing districts (Ranchi, Palamu, Godda, Hazaribagh and Lohardaga) and the result revealed that in all the locations surveyed none of the field remained free from the disease. Incidence of Collar rot ranged from 5 to 18.33 %, Wilt ranged from 12.5 to 30% and Alternaria blight ranged from 17.61 to 23.58% in the surveyed areas of Jharkhand during Rabi 2020-21. The collar region of plant turns soft, slightly contracts and begins to decay in Collar rot. Water-soaked, circular and pale brown lesions appeared on leaf margin and tip resulting in defoliation are the major symptoms of Alternaria blight whereas drooping of the petioles, rachis and leaflets followed by blackening of xylem vessel occurred as symptom of wilt. Pathogenicity of isolated pathogens were proved by three different methods viz., soil inoculation, seedling inoculation and leaf inoculation method. In respect to cultural characteristics, S. rolfsii produced extra white, dense, cottony, fan shaped, fluffy mycelium on PDA. Colony of F. oxysporum f.sp. ciceri induced cottony white mycelium having characteristic purple pigmentation. In case of Alternaria alternata, colonies were initially off white cottony which later became light green on upper surface and dark black at the bottom. Studies on morphological character of S. rolfsii revealed that the sclerotial bodies are spherical in shape, 1.2 mm dia. arranged in peripheral position. Microscopic observation of F. oxysporum f.sp. ciceri yielded ovoid to ellipsoidal microconidia having 0-1 septa. Macroconidia were fusiform, blunt at both ends with 2-4 septation and chlamydospore were globose in shape. The conidia of A. alternata were born in chains, light olivaceous to dark brown in colour, obclavate to ellipsoidal, muriform having 0-3 longitudinal and 2-6 transverse septa. Sensitivity of fungicides showed that S. rolfsii was completely inhibited by Propineb and Carboxin 37.5% + Thiram 37.5%. Complete inhibition of F. oxysporum f.sp. ciceri was achieved by Carbendazim as well as combination of Mancozeb 62% + Carbendazim 12% whereas combination of Tricyclazole 18% + Mancozeb 62% and Mancozeb 62% + Carbendazim 12% gave cent percent inhibition in the mycelial growth of A. alternata. Among bio agents, T. harzianum showed maximum antifungal activity with S. rolfsii and F. oxysporum f.sp. ciceri whereas T. austroconingii was most effective against A. alternata. Studies on integrated management showed that seed treatment with T. harzianum @ 6 g/kg + Soil drenching with Carbendazim @ 2g/L + Foliar spray with Mancozeb 62% + Carbendazim 12% @ 2g/L recorded highest seed germination, lowest disease incidence and supported maximum crop yield. Management through soil amendment resulted that seed treatment with Carbendazim @ 2g/kg + Soil application of Spent mushroom compost @ 10q/ha enriched with T. harzianum proved significantly superior in reducing Collar rot, Wilt and Alternaria blight incidence under artificial as well as natural epiphytotics. Varietal screening revealed that out of 30 entries, 4 test entries showed resistant reaction and 5 entries exhibited moderately resistant reaction against S. rolfsii. 8 test entries recorded Moderately Resistant reaction against F. oxysporum f.sp. ciceri and 2 test entries showed resistant whereas 3 entries recorded moderately resistant reaction against A. alternata.
Open Access
Study of Market diseases of Vegetables in Ranchi , Bihar
(Birsa Agricultural University, 1987) Prasad, Satyadeo; Rai, K.K.
A survey of vegetable markets of Ranchi to find out the nature and extent of losses in vegetables viz. potato , tomatom and bringal duse to fungal carses during the period of July to April 1987 revealed the following noteworthy facts
Open Access
VARIABILITY OF Rhizoctonia solani Kuhn INFECTING SMALL MILLETS AND THEIR MANAGEMENT
(Birsa Agricultural University, Ranchi, 2019) Krishnaveni, Varala; Ekka, Savita
Rhizoctonia solani Kuhn (Teleomorph: Thanatephorus cucumeris) is a soil borne, polyphagous, necrotrophic plant pathogenic fungus with a wide host range. It is causing sheath blight disease on a wide range of Graminae plant hosts and causes considerable losses in yield. The pathogen is genetically diverse showing variability in respect of cultural/ morphological and physiological characters. 100 isolates of Rhizoctonia solani were obtained from four different small millets showing typical symptoms of the disease. Among them, only 53 isolates were selected and designated based on their growth characterisics and respective host for intensive characterization. Studies on morphological character of different isolates of R. solani revealed that the variation with respect to hyphal width, distance between the septation and mycelial weight. Hyphal width of most of the isolates were having moderate to long width (5-10 μm). In foxtail millet isolates, distance between septation is more when compared to remaining isolates. Mycelial weight is maximum in finger millet isolates. Studies on cultural variability showed considerable variation among the isolates. The colony diameter is varied from 41.33-90 mm at 72 hrs of incubation. Majority of the isolates of foxtail millet and finger millet were slow growing whereas isolates of proso millet and little millet were fast and medium growing. The colony colour varied from white, light brown to brown. Concentric circle is present in most of the isolates of foxtail millet and finger millet and it is completely absent in proso millet and little millet isolates. Dispersion of mycelium varied from subdued to aerial growth. Studies on sclerotial bodies revealed that, sclerotial formation is absent in 12 isolates. Number of sclerotia per plate were varies from 11-138, in which foxtail millet isolates produced more number of sclerotia with minimum size and weight. Majority of the isolates have brown coloured sclerotia with round shape and smooth surface. In arrangement of sclerotia, foxtail millet and finger millet isolates showed greater variation with different patterns of arrangement viz., peripheral, central, central+peripheral, concentric circle or uniformly/scattered distributed. Studies on pathogenic variations revealed that variation observed in accordance with the latent period, lesion size and lesion shape. Cross inoculation studies revealed that most of the isolates of R. solani were cross infective with each other and all the proso millet isolates were highly pathogenic on foxtail millet. Host range studies unveiled that majority of the isolates successfully infect rice, sorghum, soybean, bajra except groundnut but their virulences on different crops were quite different. It was observed that slow growing isolates of foxtail millet, finger millet and little millet were more aggressive than medium and fast growing isolates. Sensitivity of fungicides against 12 isolates showed that at 0.1% conc. triazole fungicides (propiconazole, difenconazole and tebuconazole) completely inhibited the mycelial growth and sclerotial production. In further evaluation of triazole fungicides at 0.05% conc. propiconazole & tebuconazole showed significant inhibition in mycelial growth and sclerotia. Among the botanicals, clove extract of Allium sativum (Garlic) showed maximum mycelial growth inhibition. Bulb extract of Allium cepa (Onion) and rhizome extract of Zingiber officinale (Ginger) effectively reduced the sclerotial production. Among bio-control agents, Trichoderma harzianum (T. harzianum-H) procured from hyderabad showed maximum inhibition of mycelial growth whereas in field evaluation, soil application of value added Pseudomonas fluorescens + Trichoderma viride + Bacillus subtilis 335 g each of talc formulation mixed in 25 kg of FYM at the time of sowing recorded least banded sheath blight incidence of with highest grain yield in little millet and foxtail millet.