Year 2006

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CONTROL OF RHIZOME ROT OF GINGER THROUGH SELECTED CHEMICALS, BIOAGENT, PLANT EXTRACTS AND SOIL AMENDMENT
(Department of Plant Pathology, Sher-e-Bangla Agricultural University, 2006-12) NOOR-E-AMBIA
An experiment was conducted in the field laboratory of Sher-e Bangla Agricultural University, Dhaka, Bangladesh during the period from April 2006 to December 2006. Data on disease incidence and disease severity was recorded at 90, 105, 120, 135, 150 and 165 Days After Sowing (DAS) DAS with 15 days intervals and analyzed. The highest performances were observed in case of application of Trichoderma harzianum, garlic extract and neem extract in all recording days in controlling the disease. At 90 DAS, the lowest disease incidence (hill infected) recorded at 90, 105, 120, 135, 150 and 165 DAS respectively were 6.67 %, 33.33%, 33.33%, 20.00%, 13.33% and 13.33% in case of Trichoderma harzianum where it was 66.67%, 93.33, 100 %, 100%, 100% and 100%, respectively in control. Similarly the lowest disease severity (0.20, 0.80, 0.28, 0.05, 0.04 and 0.04) was recorded at 90, 105, 120, 135, 150 and 165 DAS in case of Trichoderma harzianum where it was 6.82, 20.51, 18.39, 21.97, 30.12 and 28.65, respectively in control. The promising performances were also observed in case of garlic extract and neem extract. The highest yield was recorded in case of Trichoderma harzianum (11.67 t /h) followed by garlic extract (6.33 t/h) and neem extract (6.11 t/h). The lowest yield was recorded in control (2.78 t/h) preceded by Folicur (3.65 t/h).
DETECTION OF SEED BORNE FUNGI OF SOME SELECTED MEDICINAL PLANTS
(Department of Plant Pathology, Sher-e-Bangla Agricultural University, 2006-12) BISWAS, PRADIP KUMAR
Occurrence of fungi in seeds of ten selected medi c i na l pl ant s v i z. Andr ogr aphi s , Angl e’ s t r umpet , As par agus , But t er f l y pea, Changeabl e r os e, Devi l ’ s cot t on, I ndi go, J at r opha, Li cor i ce and Ma r gos a t r ee wer e det ect ed. Inspection of dry seeds revealed that the seed samples contained apparently healthy se eds, discolored seeds and shriveled and malformed seeds. The germination percentage was recorded higher in Changeable rose (88.50%) and lower in Margosa tree (41.00%) in blotter method. Germination percentage was recorded higher in blotter method than pot soil test. Fungi were detected by blotter method both with and without pre -treatment of seeds. Hgcl (0.01%) solution was used for pre-treatment. Seven fungal species viz. Alternaria tenuis, Aspergillus flavus, Aspergillus niger, Curvularia lunata, Fusarium oxysporum, Penicillium sp and Rhizopus stolonifer were recorded from without pre-treated seeds while only three species of fungi viz. Alternaria tenuis, Curvularia lunata and Fusarium oxysporum, were recorded from pretreated seeds. All these fungi are new records for seeds of medicinal plants in Bangladesh. 2
EFFECT OF MANUAL SEED SORTING, SEED SOLARIZATION AND SEED TREATMENT WITH VITAVAX AND HOT WATER ON LEAF SPOT (Bipo/arls sorokiniana) AND GRAIN YIELD OF WHEAT
(DEPARTMENT OF PLANT PATHOLOGY, 2006) MD. ZOBAER, ABU SAYED
In vitro and in vivo experiment were carried out to determine the effect of manual seed sorting, seed solarization and seed treatment with Vitavax and hot water on leaf spot (Bipolar is sorokiniana) and grain yield of wheat during the period from November-200S to April, 2006 at the farm of Sher-e-Bangla Agricultural University, Dhaka. The experiment was laid out in the Randomized Complete Block Design (RCBD) with three replications, The highest reduction of incidence of seed-borne Bipolaris sorokiniana was obtained by manually sorted healthy looking seeds treated with Vitavax-200 (T4). Significant reduction of incidence of same fungus was achieved by treating seeds with hot' water and solar heat. Treatment of apparently healthy seed with Vitavax-200 (0.4%) was found best in reducing the leaf infection, increasing seed germination and increased seed yield which was followed by treatment of unclean seeds with Vitavax-200 (0.4%). Out of four physical seed treatment methods, solar heat treatment of apparently healthy seeds was found to be the best in reducing leaf infection, increasing seed germination and seed yield. Apparently healthy seed treated with hot water increased seed germination, seed yield and also reduced the leaf infection. Apparently healthy seeds showed more or less similar performances to that of apparently healthy seed treated with hot water. The rest of the treatments have some remarkable effect in controlling the disease and increasing seed yield of wheat.
EFFECT OF PHYSICAL AND CHEMICAL SEED TREATMENTS ON LEAF SPOT (Bipolaris sorokiniana) AND GRAIN YIELD OF WHEAT
(DEPARTMENT OF PLANT PATHOLOGY, 2006) KABIR, MD. HUMAYUN
An experiment was conducted at the Farm of Sher-e-Bangla Agricultural University, Dhaka during the period from December 2005 to April 2006 to study the effect of physical and chemical seed treatments on leaf spot (Bipolaris sorokinianaj and grain yield of wheat.There were ten treatments viz. farmer's stored seed (TI), apparently healthy seed (T2), farmer's stored seed treated with Vitavax-200 @ 0.4% (T3), apparently healthy seed treated with Vitavax-200 @ 0.4% (T4), fanner's stored seed washed with water (Ts), apparently healthy seed washed with water (T6), fanner's stored seed treated with brine solution @ 2% (T7), apparently healthy seed treated with brine solution @ 2% (T8), washed farmer's stored seed treated with brine solution @ 2% (T9) and washed apparently healthy seed treated with brine solution @ 2% (TIO). The highest germination was counted 84.20% and 86.08% respectively at 10 and 15 DAS in the treatment T4 and the lowest germination 49.84% and 55.54% at 10 and 15 DAS, respectively was recorded in the treatment TI that served as control. The lowest disease severity were recorded at panicle initiation stage, flowering stage, milking stage and hard dough _stage under the treatment T4. which were 0.06, 0.19, 0.36 and 0.84, respectively. On the other hand the highest disease severity were recorded at panicle initiation stage, flowering stage, milking stage and hard dough stage under the treatment TI, which were 0.55, 1.21, 1.69 and 2.53, respectively. The highest grain yield (3.5 t/ha) was obtained in treatment T4, which was 75% increased over control (TI).
EFFICACY OF FUNGICIDES IN CONTROLLING LEAF BLIGHT OF WHEAT CAUSED BY Bipolaris sorokiniana
(DEPARTMENT OF PLANT PATHOLOGY, 2006) ZAMAL, MD. SHAH
An experiment was carried out to determine the comparative efficacy of Vitavax-200 as seed treating chemical; Tilt-250 EC, Bavistin and Pencozeb as foliar spray in controlling leaf blight of wheat caused by Bipolaris sorokiniana under field conditions. The single effect of Vitavax-200, Tilt250 EC, Bavistin and Pencozeb were found less effective than that of combined effect of Vitavax-200 with Tih-2S0 EC. Vitavax-200 with Pencozeb and Vitavax-200 with Bavistin. The effect of seed treatment with Vitavax- 200 followed by subsequent three foliar sprays with Tilt-250 EC (Ts) has been found significantly more effective than the other single and combined effects in reducing leaf blight severity of wheat. Maximum grain yield 4.05 t/ha was found under the treatment Ts (Vitavax-200 with three sprays of Tilt-250 EC) which increased grain yield by 44.64% over untreated control. The treatment T7 resulted statistically similar effect to that of treatment Ts (Vitavax-200 with two sprays of Tilt-250 EC) in reducing leafblight severity and increasing grain yield of wheat over control.
EFFICACY OF SELECTED PLANT EXTRACTS ON LEAF SPOT (Blpolaris sorokinianai AND GRAIN YIELD OF WHEAT
(DEPARTMENT OF PLANT PATHOLOGY, 2006) ISLAM, MD. AMINUR
Efficacy of selected plant extracts was studied on t the leaf spot tBipolarts sorokiniana) and grain yield of wheat during December, 2005 to April, 2006. The experiment was conducted in the laboratory and in the farm of the Sher-e-Bangla Agricultural University,· Dhaka. Ten different treatments viz. T I (control), T2 (Vitavax 200 @ 0.3 %), T) (Onion bulb extract 1:2 w/v), T4 ( Garlic clove extracts 1:2 w/v), T, (Kalizira extracts 1:2 w/v), T6 (Zinger Rhizome extracts 1:2 w/v), T7 (Allamanda leaf extract 1:2w/v), Ts (Bishkatali extracts 1:2 w/v), T9 (Neem leaf extract 1:2 w/v) and TIO ( Mehedi leaf extracts 1:2 w/v). Were explored in the experiment in the laboratory the plant extracts were used in three concentrations i.e. 1: 1, 1:2 and 1:4 w/v. All the plant extracts except Mehedi increased seed germination in ·the laboratory in compared to untreated control. The highest incidence of seed borne Bipolaris sorokiniana was recorded under control (T). A remarkable reduction of the incidence of fungi was achieved by treating seeds with botanicals. The leaf spot severity of flag leaf and penultimate leaf and 3rd leaf differed significantly from one treatment to another at flag leaf, flowering, milking and hard dough stages. The lowest severity of flag leaf in every stage was found in treatment T2 followed by treatment Ts and treatment T4. The highest disease severity of flag leaf, penultimate leaf and third leaf in all growth stages was recorded under the treatment TI (untreated control). Significantly the highest plant height (85.77 ern) and distance between the point of flag leaf initiation and base of ear (15.62 em) were found in the treatment T4, ear length (19.98cm) in treatment Tg, number of tillers/plant (6.48) in treatment TIO, number of spikes/plot (513.66) were found under the treating seeds with botanicals. But the highest number of grains/ear (43.98), weight of grains/ear (1.88g), grain yield (3.52 t/ha) and straw yield (6.85 tlha) was found in T2~ Extract. of Onion, Garlic, Kalizira, "Zinger, Bishkatali and Neem resulted statistically similar grain yield as of seed treatment with Vitavax-200 (T2)'
MANAGEMENT· OF FUSARIUM AND NEMIC WILTS OF TOMATO BY GRAFTING, SOIL AMENDMENT, CHEMICALS AND BIO-AGENT
(DEPARTMENT OF PLANT PATHOLOGY, 2006) HOSSAIN, MD. BELAL
Efficacy of eight selected treatments viz. Grafting (Ti), Furadan 5G (T2), Bavistin (T3), Cupravit (T4), Trichoderma harzianum (Ts), Sawdust (T6), Khudepana (T7) and Control (T8) were assessed against Fusarium . oxysporum f.sp. lycopersici and Meloidogyne incognita for management of wilt diseases of tomato during winter season of 2005-2006 at the farm, allotted for the Department of Plant Pathology, Sher-e-Bangla Agricultural University (SAO), Dhaka. Significant differences were observed among the treatments in terms of wilt incidence, root gall incidence, plant growth and fruit yield. Application of Sawdust (T6), Furadan 5G (Ts) arid Grafting (Ti) showed the highest effect against the wilt pathogens where no wilt and gall incidence were observed even at 85 days after transplanting. The plant growth was influenced ahd fruit yield were increased by 206.67%, 115.12% and 103.66%, respectively for Sawdust (T6), Grafting (TI) and Furadan 5G (T2) over control. Bavistin (T3), Trichoderma harzianum (Ts) and Khudepana (T7) also gave better performance against the disease, while Cupravit (T4) showed least performance in comparison to control. Cost analysis showed that Sawdust resulted the highest BCR (8.57) followed by grafting (7.65) and Furadan 5G (7.16).
MANAGEMENT OF FUSARIUM WILT AND NEMIC WILT OF EGGPLANT THROUGH SOME SELECTED TREATMENTS
(DEPARTMENT OF PLANT PATHOLOGY, 2006) AHMMAD, ABU NOUMAN FARUQ
the effect of eight selected treatments viz. Grafting (T,), Furadan 5G (T2), Cupravit (T3), Bavistin (T4), Trichoderma harzianum T22(T5), Sawdust (T6), Khudepana (T7) and Control (Ta) were tested against Fusarium oxysporum f. sp. melongenae and Meloidogyne incognita for the management of wilt disease of eggplant during 55 days after transplanting to 95 days after transplanting at the Farm of Sher-e-Bangla Agricultural University, Dhaka. The efficacy of the treatments varied significantly in terms of wilt incidence, root knot incidence, plant growth and fruit yield. Soil application 'of Sawdust (T6), Trichoderma harzianum T22 (T5), Furadan 5G (T2) and Grafting (T,) showed promising effect against the wilt pathogens. The applied treatments enhanced plant growth and increased fruit yield by 622.08%, 605.54%, 526.250/0 and 501.67%, respectively over untreated Control (Ta). Cost benefit analysis showed that soil application of Sawdust resulted the highest BCR (4.17) followed by Furadan 5G (3.83), Trichoderma harzianum T22(3.83), and Grafting (3.16) in comparison to Control (0.70).
MANAGEMENT OF ROOT KNOT OF BANANA SEEDLINGS WITH BIOAGENT, ORGANIC SOIL AMENDMENT, CHEMICAL AND THEIR COMBINATIONS
(DEPARTMENT OF PLANT PATHOLOGY, 2006) SADAT, MD.ABU
A pot experiment was conducted for the management of root knot nematode infected tissue cultured banana seedlings with nernaticides Rugby lOG (@ 7.5 gm / plant) and Furadan 5G (@ 15 gm / plant), a neem product Neembicidin (@ 5 ml / L water), a cyst forming bacterial bio control agent Pasteuria penetrans (250 mg or 10,000 spores / plant), and a organic soil amendment Poultry Refuse (@ 2.5 kg / plant either singly or in different combination. Each pot was filled with 8 kg of soil. Six months after the investigation, it was observed that application of the treatments Neembicidin, Poultry Refuse and combination of Rugby lOG, Furadan 5G combined with Poultry Refuse reduced root knot nematodes population, gall index and improved plant growth of banana. Among the treatments poultry refuse combined with Furadan 5G appeared to be the best. Neembicidin and poultry refuse individually did not cause satisfactory improvement of plant growth.
MANAGEMENT OF ROOT-KNOT DISEASE OF BRINJAL CAUSED BY Meloidogyne spp.
(DEPARTMENT OF PLANT PATHOLOGY, 2006) 26154/00451
A field experiment was conducted for the management of root-knot of brinjal with nematicides Furadan 5G (@ 12g1plot), neem product neembicidin (@ 5 mIlL water), and organic. soil amendment poultry refuse (@ 2 kg/plot) either singly or in different combination. It was observed that application of the treatments neembicidin, poultry refuse and combination of Furadan 5G combined with poultry refuse reduced root-knot nematods population, gall index and improved plant growth of brinjal. Among the treatments poultry refuse combined with Furadan 5G appeared to be the best. Neembicidin and poultry refuse individually did not cause satisfactory improvement of plant growth. Significantly higher yield (1.5 t/ha) was found under the treatment T4 (Furadan and poultry r.efuse). But the treatment T4 resulted statistically similar effect to that of treatment T7 (Furadan 5G, poultry refuse, neembicidin) in reducing gall and increasing yield of brinjal over control. By correlation and regression study it has been found that the galling incidence hampered the crop growth in terms of shoot and root length along with fresh and dry root weight.
MANAGEMENT OF SCAB AND DIE-BACK OF CITRUS (Citrus limon L.) THROUGH BIOAGENT, PLANT.EXTRACTS AND FUNGICIDES
(DEPARTMENT OF PLANT PATHOLOGY, 2006) ALAM, MD. MAHFUZ
A research work was conducted on the standing citrus plant raised at .. citrus orchard in Sher-e-Bangla Agricultura1 University, Dhaka, during the period from May to September 2005 to investigate . the effect of bioagent, plant extracts and fungicides in controlling the scab and die back of citrus. One bioagent (Trichoderma harzianum T22), three plant extracts viz. Bishkatali (Polygonum hydropiper), Garlic (Allium sativum) and Neem (Azadirachta indica) and five fungicides viz. Dithane M-45 (0.3%), RidQmil MZ·72 (0.2%), Bavistin 50 WP (0.1%), .Champion 77 WP (0.25%) and Bordeaux mixture (1%) were applied for controlling scab and die back of citrus. The highest reduction of the scab severity (PDI) was performed by Champion 77 WP (72.72% leaf scab and 83.98% fruit scab) followed by, Bishkatali (67.54% and 79.99%), Bordeaux mixture (66.26%, and 72.01%) and Trichoderma harzianum T22(62.36% and 63.34%). The highest reduction of die-back severity (PDI) was resulted by Dithane M-45 (73.46%) fallowed by Neem extract (67.34%), Bordeaux mixture (59.19%) and Trichoderma harzianum T22 . (57.67%).Thus, the Champion 77 we (0.25%) could be used for controlling scab of citrus while Dithane M-45 (0.3%) for die-back .and ' Bordeaux mixture for both scab and die-back of citrus.
PREVALENCE OF FUNGI IN THE SEEDS AND SEEDLINGS OF BLACKBERRY
(DEPARTMENT OF PLANT PATHOLOGY, 2006) JAHAN, NUSRAT
Prevalence of fungi in seeds of blackberry plant collected from six different sources under Netrakona and Dhaka district were recorded. Seven different fungi, representing six genera, were detected in the seeds of blackberry. The seven seed borne fungi observed on blackberry seed , were Pestalotia psidii, Curvularia lunata, Fusarium equiseti, Aspergillus flavus, Aspergillus niger, Rhizopus sp. and Penicillium sp. All these seven fungi on the seeds of blackberry appear to be new records for Bangladesh. Prevalence of all these fungi varied significantly (P=1 %) with respect to location. Pathogenicity test reveals that Curvularia lunata, Pestalotia psidii and Fusarium equiseti are pathogenic to blackberry tested in five selected nurseries in two different districts. In survey, four fungi species such as Puccinia psidii, Pestalotia psidii, Fusarium equiseti and Curvularia lunata were isolated from the leaves and stems of blackberry.
ROLE OF ARBUSCULAR MYCORRHIZAL (AM) FUNGI ON GROWTH AND NUTRIENT UPTAKE OF SOME LEGUMES
(DEPARTMENT OF PLANT PATHOLOGY, 2006) ALAM, MD. SAIFUL
A pot experiment was conducted in the net house of the Department of Plant Pathology, Sher-e-Bangla Agricultural Unive~lty, Dhal?a during the period from May 2006 to December 2006 with a view to study the role of Arbuscular Mycorrhizal ~i\M) fungi on growth and nutrient uptobe of some legumes. A positive growth responseto AM was observed in all the selected legumes. The seedling emergence, plant height, shoot length and root length of inoculated legumes were comparatively higher then that of uninoculated control. The mycorrhizal inoculation suppressedroot rot, damping off and leaf blight disease of BARI Mungbean and suppressedroot rot, damping off, leaf blight and leaf spot disease of Lentil and ChicRpea. The inoculated plants showed early flowering and fruiting in comparison to uninoculated control. Mycorrhizal root colonization differed among the crops ranging from 20.00 to 49.75% and mycorrhizal dependency varied from 8.85 to 55.22%. Increasednutrient (N, P, K, $, 8 and Zn) uptal?e was recorded with the inoculated plants. Among the inoculated legumes comparatively higher N, P and K nutrient uptal?e was observed in Pigeonpea, Cowpea and ChicRpea respectively; where as S in Pigeonpea, B in Cowpea and Zn in Soybean.
SCREENING OF EGGPLANT AGAINST WILT DISEASE
(DEPARTMENT OF PLANT PATHOLOGY, 2006) RAHMAN, MD. ASHRAFUR
An experiment was conducted in the Field of SAU (Sher-e-Bangla Agricultural University) farm allotted for the Department of Plant Pathology, Sher-e-Bangla Agricultural University, Dhaka to screen out the resistant cultivars of eggplant against wilt disease. Eight cultivars viz. Nayantara, Singhnath, Dhundul, Kazla, Marich Begun Luffa, Kata Begun and Uttara were used as treatments. At 55 days after transplanting (DA T) the cultivar Luffa exhibit the highest bacterial wilt incidence (800/0) and the lowest wilt incidence was recorded in the cultivar Kata Begun (30%). At 90 OAT the highest Fusarium and Nemic wilt incidence was recorded in the cultivar Luffa and the lowest wilt incidences were recorded in the cultivar Kata Begun. The highest shoot height was recorded in the cultivar Kata Begun and the lowest shoot height was recorded in the cultivar Singhnath. The highest gall number was recorded in the cultivar Luffa and the lowest gal1 number was recorded in the cultivar Kata Begun. The highest yield per hectare (29.84 t/ha) was recorded in the cultivar Nayantara and the lowest yield (10.50 t/ha) was recorded in the cultivar Dhundhul, Among the cultivars Kata Begun graded as resistant for both Bacterial, Fungal and Nemic wilt.
STUDIES ON THE INTERACTION AMONG Rhizoctonia solani, Rhizoctonia oryzae AND Rhizoctonia oryzae-sativae CAUSING SHEATH DISEASES OF RICE
(DEPARTMENT OF PLANT PATHOLOGY, 2006) RAHMAN, MD. AKHERUR
Experiments were conducted both in laboratory and experimental field of Plant Pathology Division of Bangladesh Rice Research Institute (BRRI), Oazipur during Boro season, 2005-2006, to find out the interaction among the three Rhizoctona species namely, Rhizoctonia solani, Rhizoctonia oryzae and Rhizoctonia oryzae-sativae. In laboratory condition, the interaction between Rhizoctonia species was observed in dual culture and found that the radial growth of R. solani was always higher than the growth of R. oryzae and R. oryzae-sativae. But the radial growth of R. oryzae or R. oryzae-sativae was more or less similar. In R. solani versus R. oryzae and R. so/ani versus R. oryzae-sativae interactions, R. so/ani fused with R. oryzae or R. oryzae-sativae within 24 hours and was slightly overlapping on R. oryzae and R. oryzae-sativae, respectively at 96 hours. Both R. oryzae and R. oryzae-sativae were comparatively slow growing fungi. R. oryzae fused with R. oryzae-sativae at 96 hours but no overlapping was recorded within this period. In interactions, R. solani versus R. oryzae and R. solani versus R. oryzae sativae, the colony growth ratios (COR) of R. solani over R. oryzae and R. oryzae sativae were higher compared to control at 72 and 96 hrs after inoculation indicating positive antagonistic effect on R. oryzae and R. oryzae sativae. R. oryzae sativae did not show any antagonistic effect on R. oryzae. In field experiment, % relative lesion height (RLH) and % infected tiller were significantly differed among the combination of R. solani, R. oryzae and R. oryzae-sativae or either of two or each alone. The % RLH and % infected tiller in sheath blight were higher in R. solani only. In case of aggregate sheath spot, 0/0 RLH and infected tiller were also higher in R. oryzae-sativae alone compared to mixed with both R. solani and R. OIJ1zae or any of them. Similar trend ·was followed in sheath spot disease. The highest percentage of RLH and infected tiller were found at maturity followed by hard dough and flowering stage. Inoculation of three pathogens, R. solani, R. oryzae and R. oryzae sativae alone evidenced the highest disease severity and incidence compared to combination of three or any of two pathogens in three-growth stages (flowering, hard dough and maturity). The severity and incidence of each disease were inhibited very slightly by the inocula mixed with three or two pathogens. No significant yield losses was observed in combination of three pathogens or mixed with two or each alone. Among the three diseases, the higher % of yield losses (13.86-18.93 %) occurred when R. solani inoculated alone or mixed with both of R. oryzae sativae and R. oryzae or any of them.
STUDY ON THE QUALITY AND HEALTH STATUS OF FARMER SAVED WHEAT SEED IN BANGLADESH
(DEPARTMENT OF PLANT PATHOLOGY, 2006) TONU, NAZMOON NAHER
Quality and health status of farmer saved wheat seed of cv Kanchan grown in 2004-05 was determined by seed health and quality analysis. One hundred seed samples collected from 100 farmers representing ten upazilas under nine major wheat growing districts of Bangladesh were included for the study. Seed health and quality analysis revealed that moisture content of farmer saved seed ranged between 12.04-]3.30%. Six types seed contaminants recorded in farmers' seed were - weed seeds, insects, varietal mixture, seed with husk, other crop seed and inert matter. Farmer saved seed also contained five types of abnormal seeds viz black pointed seed, discoloured seed, undersized seed, shriveled seed and insect damaged seed. On an average, 58.48% 'clean' or 'best' seed was recovered from farmer saved wheat seed by removing the seed contaminants and abnormal seeds through manual seed cleaning. Clean seed had the highest weight, while the undersized and black point Grade 5 seeds were lighter than all other categories of wheat seed. Occurrence of seed contaminants, abnormal seeds and the sorted out clean seed from the farmer saved seed varied depending on the seed sources. Of the 13 fungi encountered in farmers' seeds, five target pathogenic fungi identified, in order of prevalence, were - Bipolaris sorokiniana, Alternaria tenuis, Curvularia lunata, Fusarium oxysporum and Aspergillus flavus. Incidence of these target fungi in both unclean and clean seeds varied significantly with respect to location of seed collection. All the five target fungal pathogens were more prevalent in farmers saved seed compared to clean seed. 'Clean' or 'best' seed significantly gave higher counts of normal seedlings and lesser percentage of abnormal seedlings and dead seeds over unclean farmers' seed and abnormal seeds like black pointed, undersized, discoloured and shriveled seeds. Similarly clean seed resulted higher germination and seedling vigour index over unclean and abnormal seeds.
VARIETAL REACTION OF LEAF BLIGHT OF WHEAT CAUSED BY Bipolaris sorokiniana
(DEPARTMENT OF PLANT PATHOLOGY, 2006) LAlLA, LUTFUN NAHER
Subsequently three experiments were conducted in the Seed Pathology Laboratory, net house and experimental field of Sher-e BangIa Agricultural University, Dhaka, Bangladesh during the period from October 2005 to April 2006 to study the varietal reaction of leaf b1ight of wheat caused by Bipolaris sorokiniana. The wheat seeds of varieties Sonalika, Kanchan, Barkat, Shatabdi, Aghrani, Pavon- 76, Akbar, Gourab, Sourav and Protiva were collected from Bangladesh Agricultural Research Institute (BARl), Gazipur. In laboratory experiment the maximum number of conidia/seed (320) was recoded for the variety Sonalika and minimum number of conidia/seed (100) was recorded in variety Shatabdi. Maximum lesion length (11.67 em) on inoculated root was recorded from the variety Sonalika. No lesion i.e. infection (0.00 em) was recorded in the varieties Shatabdi and Akbar. In blotter test maximum germination (92.00%) was recorded in the variety Shatabdi, Sourab and Agrani and minimum (72.00%) was recorded in the variety Sonalika. Maximum (37%) incidence of seed borne Bipolaris sorokiniana was recorded in the variety SonaIika and minimum (17%) in Shatabdi, At panicle initiation stage, flowering stage, milking stage and hard dough stage minimum disease severity was recorded in the variety Shatabdi and maximum in the variety SonaJika. The highest grain yield/pot (5.97 g) was recorded in the variety Gourab. In the field maximum disease severity in all the counting periods was recorded in the variety Sonalika and minimum in the variety Shatabdi. The highest number of healthy spikelets/ear (26.77), number of grains/ear (38.66), number of healthy grains/ear (37.41) and IOOO-seedweight (42.12 g) were recorded in the variety Shatabdi. The highest grain yield/plot (391.77 g) was recorded in the variety Shatabdi and the lowest yield/plot (183.08 g) was recorded in the variety Aghrani.
VARIETAL SCREENING AND MANAGEMENT OF LEAF BLIGHT OF WHEAT CAUSED BY BIPOLARlS SOROKINIANA
(DEPARTMENT OF PLANT PATHOLOGY, 2006) Shahidullah, Mohammad
Experiments were conducted at Bangladesh Agricultural Research Institute (BARI) Joydebpur, Gazipur during 2004-2005 crop season. In field screening of 14 germplasms under natural infection pressure of Bipolaris leaf blight 3 reached as resistant (Chirya-7, Shatabdi and BAW-966) and 1 reached as moderately resistant (BA W -1006) to the disease. All the five fungicides (Avistin-O.l %, Hayconazole- 0.05%, Nuben-0.2%, Sulphotox-0.2% and Tilt0.05%) tested against Bipolaris sorokiniana, showed better performance over control. Among them Tilt appeared most effective and resulted against the PDI value of 72% and increased 108% grain yield over control. While effective dose of four fungicides namely folicur (0.05 and 0.10%), Hexaconazole (0.05 and 0.1 %), Fujione (0.05 and 0.1%) and Akanazole (0.05 and 0.1 %) were evaluated against Bipolaris leaf blight it was found that F2 D2.Exhibited most effective one in reducing the disease and increasing higher yield and it showed statistically similar to FIDI (Folicur, 0.05%) FID2 (Folicur, 0.1%) and F2Dl <, (Hexaconazole (0.05%). In another study on determining avoidable loss of wheat due to Bipolaris leaf blight indicated avoidable loss of27.05 and 14.20% were due to the disease respectively, in Kanchon (Susceptible) and Shatabdi (Moderately resistant) varieties.
VARIETAL SCREENING AND MANAGEMENT OF UFRA DISEASE OF RICE
(DEPARTMENT OF PLANT PATHOLOGY, 2006) ULLAH, MD. WALl
A total of 52 rice entries were tested, 4 entries, namely FUKUHONAMI, MATSUHONAMI, AKIYU TAKA, HA YAKlKARI and showed highly resistance (HR) reactions to ufra, 9 entries viz. IR30, AOKAZI, KOSHINISHINI,' KINONISHIKI, AKINISHlKI, SHINANOKOGANE, HUNENW ASE, RA YEDA4849 and RA YEDA4851 showed resistant (R) reactions, 30 showed intermediate or moderate resistance (IRJMR) reactions and 9 showed susceptible (S) reactions to ufra. The entries belonging to the HR· and R groups had a low number of infested tillers with or without symptoms. Effectiveness of Furadan 5G in soil was evaluated against ufra disease of rice at different intervals of application. The ufra infestation was lower and the number of healthy panicle was higher at the application of Furadan 5G just at transplanting. The infestation was significantly reduced at the application of Furadan 5G up to 20 days before transplanting. The length of effectiveness of Furadan 5G in soil was 20 days approximately. Therefore, in controlling ufra and increase yield, Furadan 5G @ 1kg ai/ha should be incorporate into the soil at transplanting. Three granular nematic ides namely Cemifuran 5G, Edfuran 5G and Brifar 5G @ 1kg ai/ha were evaluated against ufra disease of rice in comparison with Furadan 5G. In T. Aman and Boro, 2005-2006, the damaged tillers and total ufra were significantly higher in the control (diseased) plots compared to control (healthy) or nematicidal treatments. Accordingly, Cemifuran 50, Edfuran 5G and Brifar 5G treated plots had 37.53-52.74% apparently healthy panicles with 3.56-4.02 t/ha yield in T. Aman while those nernaticides had 31.66-52.98% healthy panicles with 3.37-3.59 t/ha yield in Boro season. The obtained yields of three nematicides (3.56-4.02) were close to control (healthy) treatment (4.48 t/ha) in T. Aman. A considerable yield increase (3.37-4.02 t/ha) was also observed in three new nematicides over the control (diseased) treatment in both seasons. However, the test nematic ides could be used in controlling ufra disease incidence and also increasing yield of rice.