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Professor Jayashankar Telangana State Agricultural University, Hyderabad (Telangana State)
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ThesisItem Open Access A COMPREHENSIVE STUDY ON MAIZE PRODUCTION AND MARKETING IN TELANGANA STATE - AN ECONOMETRIC APPROACH(PROFFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY, 2024-04-19) MARKA MAHESHNATH; DR. R. VIJAYA KUMARITelangana state ranks third position in Maize cultivation area and it is cultivated across the state in approximately 12.68 lakh hectares. This research aims to comprehensively analyze the production and market dynamics of maize in Telangana State. By understanding historical trends, forecasting future production and market prices, and evaluating the economics of maize production and marketing, this study seeks to provide insights into the state’s maize production. Additionally, it aims to examine price transmission between key markets in Telangana and India, identifying constraints in production and marketing and proposing policy measures to address these challenges, ultimately aiming to enhance the efficiency and sustainability of the maize sector in the region. Warangal Rural, Siddipet and Kamareddy districts of Telangana, which ranked top three in area under maize cultivation in the state were purposively selected for the study. Similarly, top two mandals in each district and top two villages in each sample mandal were selected. The required primary data for the study was gathered from 240 randomly chosen sample farmers from the selected villages using pre-tested, well structured schedules through personal interviews for the agricultural year 2019-20. District wise time series data on area, production, productivity and market prices of maize for the period from 1966-67 to 2021-22 were collected from different secondary sources. Trend analysis, cost and return analysis, marketing efficiency and co-integration analysis were employed to achieve the set of objectives and draw meaningful conclusion. The results of the study revealed that maize productivity in Telangana improved significantly, rising from 3204 kg/ha in 2001-02 to 6713 kg/ha in 2020-21. The average market price of maize in Telangana has shown an upward trend, increasing from ₹ 555/qtl in 2001-02 to ₹ 1669/qtl in 2020-21. The study also reveals that maize cultivation in Telangana follows intricate growth patterns, possibly influenced by a combination of factors. The cubic and power models provided better insights into these trends compared to simpler models. Using the ARIMA (2,1,2) model, it was forecasted that maize prices in Telangana would be ₹ 2182.16 in January 2023 and ₹ 2067.90 in December 2023 and also maize production in Telangana was forecasted to be 23.10 LT in 2022-23, 23.46 LT in 2023-24, and 23.82 LT in 2024-25. Price transmission between the markets explained unidirectional causality in Nagarkurnool-Badepally, Siddipet-Badepally, and Nizamabad-Nagarkurnool pairs, where changes in the former market affected price formation in the latter market. The remaining markets did not exhibit causality, indicating that price changes in one market did not feedback to influence the other. The findings also revealed that the average overall cost of cultivating maize per hectare was Rs. 80536.70, Rs. 80875.84, and Rs. 80264.72 in the districts of Warangal Rural, Siddipet, Kamareddy, respectively. The same on pooled farms was found to be Rs. 80775.57. With regard to gross income, Warangal Rural district reported the highest ₹ 144,619.75 per hectare, showcasing strong revenue generation from maize cultivation. Siddipet had the lowest gross income at ₹ 120,119.64 per hectare. Warangal Rural is the most profitable district for maize cultivation, while Siddipet is the least profitable among the studied regions. With respect to the marketing efficiency, price spread was ₹ 470.66 per quintal for Channel I and ₹ 449.30 per quintal for Channel II. The analysis of marketing margin and marketing efficiency in maize marketing revealed variations in prices, margins, and efficiency between the two channels. The Garette ranking analysis depicted uncertain rainfall (83.13) and shortage of labour (79.95) as the major constraints faced by farmers in maize production with maximum scores. In case of marketing, more number of middlemen in the market (82.65) and price fluctuations (79.13) were found as the major marketing constraints. The study presents a comprehensive overview of maize production, market trends, and constraints in Telangana State, highlighting significant improvements in productivity and price escalation over the years. Notably, maize productivity doubled between 2001 02 and 2020-21, while prices experienced a substantial upward trajectory during the same period. Forecasting models revealed anticipated price and production figures for 2023-24 and 2024-25, aiding in future planning. Price transmission analysis identified key market relationships, delineating causality and inter-market influences. Additionally, cost analysis per hectare and gross income across districts unveiled varied profitability, with Warangal Rural emerging as the most lucrative region for maize cultivation. Constraints such as uncertain rainfall and limited access to inputs and credit were highlighted, particularly affecting small and marginal farmers. The study underscores the potential positive economic impacts of maize farming on farmer incomes and the state economy, offering valuable insights for farmers and policymakers to optimize farming practices, investments, and policy interventions. The results of the study suggested that, shifting focus towards cost-effective production technologies and farm machinery will boost productivity and farmers income. Public sector initiatives to produce high-quality maize seeds at affordable rates can compete with the private sector, ensuring seed availability. Encouraging farmer cooperatives for collective production and marketing can elevate income levels. Establishing widespread marketing systems for fair maize procurement can incentivize farmers to continue cultivation. Low-cost storage infrastructure and market tie-ups with industrial units will prevent market gluts and strengthen the maize value chain. Additionally, setting up feed manufacturing units in major growing areas can further expand maize production, while disseminating price forecasts through digital platforms can mitigate price risks and volatility, aiding farmers in decision-making regarding production, storage, and marketing strategies. Implementing these policy implications can significantly enhance maize farming in Telangana StateThesisItem Open Access EVALUATION OF DUAL TOXIN TRANSGENIC Bt COTTON HYBRIDS AGAINST INSECT PESTS OF COTTON(PROFFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY, 2014-05-06) B.DILEEP KUMAR; Dr. D.SRIDEVIThe performance of dual toxin transgenic Bt cotton hybrids viz., Bunny, Mallika, Neeraja, Brahma, Tulasi-9, RCH-2, RCH-530 and a non-Bt hybrid, Orugallu Krishna (WGHH-2) against insect pests of cotton in both field and laboratory were undertaken during Kharif, 2011-12 and 2012-13 at Regional Agricultural Research Station, Warangal. The population (pooled mean for both the years) of aphids and whiteflies showed no significant variation among the various BG-II/non-Bt hybrids under protected conditions. The population ranged between 3.87 and 5.32 and 1.50 to 2.04/top 3 leaves in aphids and whiteflies, respectively. However, leafhoppers and thrips varied significantly amongst the various BG-II/non-Bt hybrids. The population of leafhoppers was significantly lowest in non-Bt Orugallu Krishna (1.53 leafhoppers/top 3 leaves) and was on par with only Neeraja (1.60 leafhoppers/top 3 leaves). The population ranged between 1.80 and 3.29 leafhoppers/top 3 leaves in the remaining hybrids, the highest (3.29 leafhoppers/top 3 leaves) being in RCH-2. The population of thrips ranged between 9.77 and 17.80 thrips/top 3 leaves. A total of six need based sprayings were required for dual toxin Bt hybrids to manage the sucking pest complex in both kharif, 2011-12 and 2012-13. During both the years the cost-benefit ratio was found to be higher in RCH-530. Egg laying by bollworms in dual toxin Bt cotton hybrids was almost nil in BG II/non-Bt hybrids during kharif 2011-12, while in kharif 2012-13, non significant differences with respect to the number of eggs laid in different BG-II/non-Bt hybrid were observed. Larvae of Helicoverpa armigera (Hubner), Spodoptera litura (Fabricius) and Erias vitella (Fabricius) were observed in non-Bt Orugallu Krishna but below ETL while in dual toxin Bt hybrid none were recorded. The incidence of pink boll worm[Pectinophora gossypiella (Saunders)] during both the years was nil. There was significant difference in mortality of H. armigera and S. litura larvae between BG-II and non-Bt Orugallu Krishna. BG-II hybrids were highly effective against the first instar larvae of both H. armigera and S. litura compared to later instars. Irrespective of the age of leaves and squares, Neeraja and Mallika, respectively, were superior in suppressing all the three instars of H. armigera while in S.litura variable responses were observed. The studies on effect of age of different plant parts of BG-II cotton hybrids on the mortality of larvae of H.armigera have shown that irrespective of the age of leaves and squares, Neeraja and Mallika, respectively, were superior in suppressing all the three instars. However, with respect to bolls, 90 day old bolls of RCH-530 and 120 day old bolls of RCH-2 and Mallika were effective against all the three larval instars. The studies on the effect of age of different plant parts of BG-II cotton hybrids on the mortality of larvae of S.litura has shown variable responses to different plant parts. 60 and 90 days old leaves of RCH-530 were effective against all three instars, while 120 days of RCH-2 and Mallika were effective against first and second instars and first and third instars, respectively. With regards to squares, irrespective of age of squares, Tulasi-9 gave better control of third instar larvae. However, the performance of bolls varied i.e 90 days bolls of Tulasi-9 were effective against third instar while 120 days old bolls of RCH-530 were effective only at 5 DAR while at 10 DAR Bunny, Mallika and Neeraja were superior. Also, the mortalities of S. litura larvae were greater on leaves followed by squares and bolls. The effect of age of various plant parts (leaves, squares and bolls) on the pupation and adult emergence of third instar larvae of H. armigera and S.litura showed that the percentage pupation and adult emergence in non-Bt Orugallu Krishna was significantly high compared to Bt hybrids. The effect of age of leaves on the larval weights of different instar larvae of S. litura showed that there was significant reduction in the larval weights when fed with dual toxin Bt cotton leaves compared to non-Bt leaves. Cry 1Ac content was highest in leaves compared to squares and bolls, while Cry 2Ab recorded highest levels in squares compared to leaves and bolls. Cry1 Ac levels were higher in leaves at 90 DAS compared to 60 and 120 DAS. Significantly lowest trichomes were registered in RCH-2 (35.60 / 4 x microscopic area) indicating that this hybrid was highly susceptible to leafhoppers attack. The efficacy of different insecticides against leafhoppers in RCH-2 revealed that diafenthiuron 50% WP was the most effective.ThesisItem Open Access BIOPOLYMER BASED MULTILAYER SEED COATINGS WITH TRICHODERMA, RHIZOBIUM OR BACILLUS AND COMPATIBLE FUNGICIDES AGAINST SEED AND SOIL BORNE DISEASES IN SESAMUM, GROUNDNUT AND SOYBEAN(PROFFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY, 2023-01-09) Vijay Kumar, S.; Rajeswari, B.Sesamum, groundnut and soybean are important oilseed crops grown in many parts of the world. Among different fungal diseases, Macrophomina phaseolina in sesamum and soybean, Sclerotium rolfsii in groundnut are common, widespread and causing significant yield losses. M. phaseolina in sesamum and soybean, S. rolfsii in groundnut were isolated from infected plant parts and purified by hyphal tip method. Pathogenicity test was conducted on susceptible sesamum cv. Swetha Til, groundnut cv. K-6 and soybean cv. JS-335. Pathogen was re-isolated from artificially inoculated plants and found similar in all aspects thus fulfilling Koch’s postulates. The efficacy of six bioagents viz., T. asperellum (TaDOR 7316), Trichoderma sp. (T16), T harzianum (Th), T. asperellum (Ta10), T. asperellum (Ta11) and T. harzianum (Th4d) were evaluated against M. phaseolina isolates of sesamum and soybean and S. rolfsii of groundnut. The results revealed that among six bioagents tested, T. harzianum (Th4d) was found effective in inhibiting the mycelial growth of M. phaseolina of sesamum (66.3 %), S. rolfsii of groundnut (71.9 %) and M. phaseolina of soybean (67.0 %), respectively. The efficacy of five fungicides viz., carboxin 37.5 % + thiram 37.5 %, tebuconazole 25 % EC, mancozeb 75 %WP, penflufen 13.28 % w/w + trifloxystrobin 13.28 % w/w FS and chlorothalonil 75 % WP were evaluated under in vitro by poisoned food technique against M. phaseolina isolate of sesamum, S. rolfsii of groundnut and M. phaseolina isolate of soybean. Among five fungicides tested, penflufen + trifloxystrobin, chlorothalonil and tebuconazole were found effective at all the concentrations with 100 % inhibition in M. phaseolina of sesamum. Similarly, penflufen + trifloxystrobin fungicide was found highly effective at all the concentrations tested and inhibited 100 % growth of S. rolfsii in groundnut and M. phaseolina of soybean when compared with control. In-vitro compatibility of carboxin 37.5 % + thiram 37.5 %, tebuconazole 25 % EC, mancozeb 75 %WP, penflufen 13.28 % w/w + trifloxystrobin 13.28 % w/w FS and chlorothalonil 75 % WP at 20, 50, 100, 250, 500, 750 and 1000 ppm concentrations were tested with three Trichoderma isolates i.e., T. harzianum (Th4d), T. asperellum (TaDor 7316), T. harzianum (Th) and Bradyrhizobium sp., B. subtilis. Among five fungicides, penflufen + trifloxystrobin was found compatible with T. harzianum (Th4d) at all the concentrations of 20, 50, 100, 250, 500, 750 and 1000 ppm with 90 mm growth was observed. In case of bacterial bioagents, penflufen + trifloxystrobin was found compatible with Bradyrhizobium sp. and recorded OD value of 1.188 at 1000 ppm concentration. Compatibility among three Trichoderma isolates with Bradyrhizobium sp. and B. subtilis indicated that Trichoderma was over grew on Bradyrhizobium sp. and without formation of inhibition. Whereas, the growth of Trichoderma isolates were inhibited by B. subtilis isolate. Characterization of chitosan films were done by Fourier-Transform Infrared Spectroscopy (FTIR) and variation was observed in presence of fungicides and bioagents. Scanning Electron Microscope (SEM) microphotographs showed rough texture of chitosan blend film and undulation were observed in chitosan blended film with T. harzianum (Th4d) and Bradyrhizobium sp. was due to presence of spores of both bioagents. Standardization of multilayer seed coating with combination of biopolymer chitosan, fungicide and bioagents with different concentrations were tested in groundnut cv. K-6 under in vitro by using small pots and kept in growth chamber at 25± 20C with 90 per cent relative humidity. Among different seed treatment combinations tested, the double layer seed coating consisting of chitosan + fungicide + T. harzianum Th4d and chitosan + Bradyrhizobium sp. showed higher germination percentage and seedling vigour index - I and seedling vigour index - II as compared to three layer and single layer seed coating in all the concentrations tested. Combination of effective fungicide (penflufen + trifloxystrobin) with potential biocontrol agents (T. harzianum (Th4d) and (Bradyrhizobium sp.) and seed coat biopolymer chitosan and their combinations were tested against M. phaseolina of sesamum and soybean and S. rolfsii of groundnut by rolled paper towel method. Among different treatments, T5 treatment with double layer seed coating with chitosan 5 ml + fungicide 7.5 ml + Th4d 0.1 g as inner layer and chitosan 5 ml + Bradyrhizobium sp. 0.5 g as outer second layer was significantly enhanced seed germination per cent in sesamum and soybean (86.7 %) and groundnut (100%) as compared with untreated control (without pathogen) recorded germination of 71 %, 70 % and 80 %, respectively. Whereas under inoculated conditions with pathogen, the per cent seed germination was significantly enhanced in sesamum (83.8 %), soybean (83.1 %) and groundnut (94.0 %) as compared to untreated control with 59.0 %, 66.2 % and 64.0 %, respectively. In pot culture studies, the maximum per cent germination in sesamum and groundnut was recorded in T5 treatment with 80.0 % and 94.0 %, respectively. Whereas in soybean, the highest germination per cent was recorded in T5 and T7 treatments with 82.5 % of germination which was on par with each other. Disease incidence was low in T5 treatment with 21.6 %, 11.7 % and 13.1 % in sesamum, groundnut and soybean, respectively. Storability and shelf studies in seed coatings with biopolymer chitosan, fungicide and bioagents and their combinations in sesamum, groundnut and soybean at four months storage period revealed that seed quality parameters viz., seed germination and seed vigour index-I and seed vigour index II were gradually decreased with increase in period of seed storage. Maximum seed germination per cent of 81.4 %, root length (11.9 cm), shoot length (4.7 cm), SVI-I (1351), SVI-II (5.4) and dry weight (0.066 g) in sesamum were recorded in T5 treatment at the end of four months period of seed storage. The data on shelf life (Log CFUs) of T. harzianum (Th4d) and Bradyrhizobium sp. on coated seeds of sesamum recorded more number of colony forming units in T3 treatment (chitosan 5 ml + fungicide 7.5 ml + Th4d 0.1 g) + (chitosan 5 ml + Bradyrhizobium sp. 0.5 g) with 4.92 and 2.94 Log CFU g seed-1 of both T. harzianum (Th4d) and Bradyrhizobium sp., respectively. At the end four months period of seed storage in groundnut, recorded maximum germination per cent of 86.7 %, root length (19.6 cm), shoot length (10.1 cm), SVI-I (2254), SVI-II (49.8) and dry weight (0.33 g) in T5 treatment. The results on shelf life of T. harzianum (Th4d) and Bradyrhizobium sp. on coated seeds of groundnut recorded more number of colony counts in T3 treatment with 2.86 Log CFU g seed-1 and 4.69 Log CFU g seed-1 , respectively. Maximum germination of 78.8 %, root length (24.9 cm), shoot length (15.0 cm), SVI I (3137), SVI-II (41.1) and dry weight (0.52 g) were recorded in T5 treatment. The results on shelf life (Log CFUs) of T. harzianum (Th4d) and Bradyrhizobium sp. on coated seeds of soybean recorded more number of colony counts in T3 treatment with 2.86 Log CFU g seed-1 and 4.79 Log CFU g seed-1 , respectively at the end of four months period of seed storage in soybean. The results on persistence of T. harzianum (Th4d) and Bradyrhizobium sp. in chitosan and fungicide film after application in sterilized red and black soils in absence of plants over 120 days period revealed that maximum colony forming units of T. harzianum (Th4d) were recorded in T3 treatment with 3.54 and 3.50 Log CFUs/g. Whereas in Bradyrhizobium sp. the maximum colony forming units were observed in T3 treatment with 5.34 and 5.27 Log CFUs/ g at 90 days after application (DAA). Root colonization efficacy of T. harzianum (Th4d) and Bradyrhizobium sp. in sesamum, groundnut and soybean crop in red and black soil types were assessed at 15, 30 and 45 DAS. The maximum number of T. harzianum (Th4d) and Bradyrhizobium sp. colony forming units were observed in red soils in sesamum and groundnut crops whereas black soils in soybean crop at 45 DAS. In sesamum and soybean crops, the influence of seed coatings with effective fungicide (penflufen + trifloxystrobin), potential biocontrol agent (T. harzianum (Th4d), Bradyrhizobium sp.) and seed coat biopolymer (chitosan) and their combination under glasshouse were studied. The highest germination per cent, plant height (cm), number of pods per plant, hundred seed weight (g), seed yield per plant (g), number of seeds per pod and seed yield per ha (q) and low disease incidence (%) were recorded in T5 seed treatment. Effect of seed coating on biochemical parameters viz., oil content, protein and fatty acid content in sesamum and soybean were differed. In groundnut, the influence of seed coatings with effective fungicide (penflufen + trifloxystrobin), potential biocontrol agents (T. harzianum (Th4d), Bradyrhizobium sp.) and seed coat biopolymer (chitosan) and their combinations were tested under field conditions. The results indicated that highest germination per cent was recorded in T5 seed treatment with 91.9 %, field emergence index (84.8 %), plant height (42.8 cm), nodules (279.0), number of pods per plant (40.7), hundred seed weight (38.5 g), seed yield per plant (22.40 g), number of seeds per pod (1.84), seed yield per ha (21.1 q), haulm yield (4760.0 kg), B:C ratio (1:2.41) and low disease incidence (5.2 %) and AUDPC (102.8). Effect of seed coatings on biochemical parameters viz., oil content, protein and fatty acid content in groundnut were significantly different. Among seed treatments the higher oil content, protein content were recorded in T5 treatment with 52.85 % and 23.6 %.ThesisItem Open Access DEVELOPMENT AND EVALUATION OF MANALI TAMARIND (Pithecellobium dulce) BASED FUNCTIONAL FOODS(PROFFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY, 2023-01-04) Rachana Sree, S; Supraja, T.Underutilized horticultural crops were those that are not sold widely or farmed on a significant scale for commercial purposes. Local people grow, trade and consume these products. These crops are easier to grow, even in unfavourable climatic and soil circumstances. Therefore, taking advantage of underutilized horticulture crops can help to address the socioeconomic issues of poor health, nutrition, unemployment, and poverty. By satisfying the dietary needs of vulnerable individuals, the consumption of underused fruit crops provides nutrition to the poor and destitute tribal people. They are a rich source of carbohydrates, lipids, proteins, energy, vitamins A, B1, B2, B3, B6, B9, B12, C, folic acid, minerals, Ca, P, Fe and dietary fibre. Manali tamarind was procured from different places like Nalgonda, Jagityal, Hyderabad and Bhadrachalam. Raw material was cleaned thoroughly, tray-dried at 60°C for 5 ½ hours and stored in plastic containers for further use. The fresh and dried aril was analysed and the dried aril (DA) proximate, mineral content was increased due to the increased concentrations of the nutrients when subjected to the drying process compared to FA. The vitamin C and aw content of fresh aril (FA) was high due to their heat and light-sensitive nature compared to DA. The intensity of the colour increased for DA due to drying temperature and time. Functional parameters like WAI, WSI, ORC and FC were good for DA powder due to its high solubility because of the uniform particle size and shape. Ready-to-use products (chutney powder, beverage powder, pickle 10% to 70% incorporation) and ready-to-eat products like (curd, yoghurt and ice cream 5% to 35% incorporation) were developed. The best formulation from each product was selected by using sensory evaluation as follows chutney powder with 40% (SCP4), beverage powder with 30% (SBP3), ice cream with 10% dried aril powder (SIC2), pickle with 30% (SP3), curd with 5% (SC1) and yoghurt with 10% incorporation of fresh aril paste (SYH2) was further subjected to proximate, physical and functional analysis. All the selected products were low in CHO and energy compared to the control. The total sugars, reducing sugars and non-reducing sugars were higher for samples than that of controls due to the incorporation of aril powder and paste. The physical parameters like TSS, TA and TI of the samples increased due to the aril powder present in them. The most accepted product during the sensory evaluation was pickle followed by chutney powder. The functional properties of sample pickles were high compared to the control due to the aril incorporation where WAI was 1.82±0.04ml/g, WSI was 28.73±8.86%, ORC was 3.51±0.07ml/g and FC was 1.79±0.00%. The moisture, protein, total sugars, reducing sugars and non-reducing sugars content of the sample pickle was high compared to the control which was 35.9±81.05%, 3.82±0.01%, 15.99±0.06%, 4.10±0.06% and 11.89±0.03%. The shelf life of the selected products based on TMC and TBC revealed that chutney powder (40%), beverage powder (30%) and pickle (30%) performed well during the entire study period of 90 days. Whereas, for sample ice cream (10%) it was 45 days, curd (5%) and yoghurt (10%) performed well for 30 days. All the storage parameters like pH, TSS, TA and moisture content showed variation during the storage period. All the products were subjected to sensory evaluation during the 15-day interval period and all the products were high to moderately liked by the panellists. Consumer evaluation was conducted with 100 respondents of the age group 15- 65 years, all the selected products scored well and the acceptability of yoghurt was high compared to the other products. The respondents were ready to use them in their day-to day lives and can afford up to 30/- to 50/- for the 100g based on the variability of products.ThesisItem Open Access STUDIES ON VARIABILITY AND INTEGRATED DISEASE MANAGEMENT OF WILT OF SAFFLOWER (Carthamus tinctorius L.) CAUSED BY Fusarium oxysporum f. sp. carthami(PROFFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY, 2022-07-02) Rajendra prasad, M.; Vidya Sagar, B.Safflower (Carthamus tinctorius L.) is one of the major Rabi oilseed crop cultivated in the Deccan Plateau region of India. Wilt of safflower caused by Fusarium oxysporum f. sp. carthami Klisiewicz and Houston (Foc) results in yield loss up to 93 per cent in susceptible varieties. Wilt samples of safflower were collected from different locations of Telangana and Andhra Pradesh and fifteen isolates of Fusarium oxysporum f. sp. carthami were isolated from the collected diseased samples and they designated as FOC 1 to FOC 15. Morphological variations among collected isolates were studied. Based on the observed length of microconidia the isolates could be divided into 5 distinct groups i.e. Group I to V, based on macroconidia length the isolates could be divided into 3 distinct groups i.e. Group I to III. Based on chlamydospore diameter, the isolates could be divided into four distinct groups (Group I to IV), based on the cultural characters they were categorized into eight distinct groups (Group I to VIII) and based on colony diameter the isolates grouped into seven distinct groups (Group I to Group VII). The variation was present among the isolates at molecular level and the isolates were grouped into different clusters. The results of molecular variability revealed that There was a relationship exists between clustering of isolates based on molecular variability with the location. Pathogenic variability of the fifteen isolates of Fusarium oxysporum f. sp. carthami was tested using susceptible safflower cultivar PBNS-12 under high inoculum pressure in glasshouse conditions. Wilt incidence was recorded in the range of 53.3 % (FOC-11) to 93.3 % (FOC-I). Forty one germplasm lines were collected from ARS, Tandur and were screened against Fusarium oxysporum f. sp. carthami. Based on the disease scale (0-9), they were categorized from highly resistant to highly susceptible. Seed mycoflora detected from the seeds of 41 germplasm lines by using standard blotter method and agar plate methods. In both the methods, eight fungal genera viz., Alternaria spp., Aspergillus flavus, Aspergillus niger, Chaetomium spp., Rhizopus spp., Curvularia spp., Macrophomina phaseolina and Fusarium spp. were recorded. Among the observed fungi A. niger was found predominant (40.28 % and 42.52 %), while M. phaseolina was least (2.39 % and 2.02 %). Effect of fungicides and biocontrol agents on seed germination, seedling vigour index and seed mycoflora was evaluated on four popular verities of safflower viz., Nira, ISF-764, PBNS-12 and Manjira by standard blotter method and paper towel method. Seed treatment with captan (0.25 %) was found superior followed by seed treatment with Trichoderma harzianum (1 %), in all the four popular varieties tested in the testes parameters. Susceptible variety PBNS-12 was used to find the effect of seed treatment with bioagents, organic amendments and carbendazim and their combinations on per cent seedling emergence, pre emergence and post emergence mortality in glass house conditions. Among all the treatments tested, T11-combination treatment of (T1 + T2 + T3 + T4 (seed inoculation with test pathogen followed by seed treatment with Trichoderma harzianum (10 g kg-1 seed) + T2 (seed treatment with Pseudomonas fluorescens (10 g kg 1 seed) + T3 (seed treatment with carbendazim (1 g kg-1 seed) + T4 (soil application with neem cake (10 g kg-1 soil) was found superior in all the parameters discussed. When tested for growth parameters, shoot length was recorded highest in T11 (59.2 cm), root length was recorded highest in T6 (10 cm) and Total length was recorded highest in T11 (68.2 cm). Highest fresh weight (272.10 g) and dry weight (105.35 g) was also recorded from the same combination treatment. In integrated disease management experiment, when the cost benefit ratio is compared, T16 (Seed treatment with carbendazim) was found effective with C:B ratio of 1:67 followed by T14 Seed treatment with Trichoderma harzianum + Seed treatment with Pseudomonas fluorescens (1:52) and T3 Seed treatment with Trichoderma harzianum (1:50). Among the above treatments, T16 recorded highest yield (1681 kg ha 1 ) highest germination (88.42 %) and lowest wilt incidence (15.12 %) followed by T14 (Seed treatment with Trichoderma harzianum + Seed treatment with Pseudomonas fluorescens) recorded yield of 1580 kg ha-1 , germination of 82.33 per cent and wilt incidence of 22.10 per cent respectively.ThesisItem Open Access STUDIES ON INTERACTION OF LEAF AND NECK BLAST CAUSED BY Magnaporthe oryzae (Hebert) Barr AND ITS MANAGEMENT(PROFFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY, 2022-11-21) Rajeswari, E.; Vidyasagar, B.The present investigation was undertaken with an aim to know the interaction of leaf blast and neck blast pathogen population to host and the variability of isolates using cultural, morphological, pathological, molecular characteristics and avirulent gene distribution. Further efforts were also made to identify the effective R-gene for both leaf blast and neck blast resistance. Attempts were also made to manage the disease with non-chemical and biocontrol agent T. asperellum in integration. A survey on incidence of rice blast disease was conducted in 13 major rice growing districts of Telangana. The incidence varied from 8.24 per cent in Vikarabad district to 58.26 per cent in Warangal district. Disease incidence was recorded among all the prominent cultivars grown in their particular regions and it was observed that different cultivars showed different levels of incidence irrespective of the regions. Among the different cultivars, HMT Sona showed the highest incidence of 71.33 per cent whereas, cultivar Tellahamsa with 49.16 per cent incidence. The maximum isolation rate of the pathogen M. oryzae was recorded from Siddipet with 75 per cent followed by Mehbubnagar with 50 per cent. The disease was observed from nursery to grain hardening stage. A total of 40 monoconidial isolates of Magnaporthe oryzae were established. Out of forty isolates, 36 were leaf blast and 4 were neck blast isolates. The Principal Component Analysis (PCA) was performed for analyzing all forty isolates of M. oryzae growth pattern in 10 different media by considering different components (sectors, zonations, wrinkles, elevation, colony colour, Radial growth and growth rate) for studying cultural variability in M. oryzae population of Telangana. The components elevation, sectors, zonations and wrinkles have been observed to be in strong association among each other (F2: 23.59%). From the eigen value data, it was observed that three components (wrinkles, zonations and sectors) accounts for eigen values more than one and highest variance as indicated in PCA analysis. In present investigation it was ascertained that even in presence of different carbon compounds, host extracts as media source to the isolates their effect was insignificant i.e., irrespective of the carbon source and host extracts the above three parameters were not affected significantly. Oat meal agar was found best for supporting the growth of M. oryzae. However, ragi leaf extract agar media recorded as best for sporulation. Sucrose as carbon source and ammonium nitrate favours the growth of M. oryzae. Morphological variability among M. oryzae isolates was studied through the conidial morphology. Among the isolates, the overall size of the conidia was 14.43-26.80 µm × 3.68- 8.76 µm (Length × Width). A total of 25 rice host differentials with different combinations of resistance genes were tested in for rice blast resistance. Among 25 genotypes tested, NILA57, RamanadStr3, Shia-tia-tsao, Tetep, Tadukan and Dular were found resistant. Genotypes CO 39 and HR 12 were highly susceptible genotypes. A total of 18 races were identified among them the most frequently occurred race was ID-14 followed by IB-41. M. oryzae isolates were identified further to species level with ITS4 and ITS5 universal primers. Actin and TEF 1 α gene primers were also used for further accuracy of identification of conserved sequence, in order to support the morphological identification of M. oryzae isolates. In case of ITS region, all the isolates were appeared as identical by producing the amplified fragment of 560 bp. PCR amplification with actin gene and TEF 1 α gene produced the 336 bp and 550 bp amplicon with DNA from all fourty isolates. These results further confirmed by sequencing of ITS region and identified the isolates as M. oryzae, the pathogen is same that causes both leaf and neck blast. The genetic diversity of M. oryzae isolates was studied using a total of 8 SSR markers and 10 RAPD markers. The polymorphic information content value was high for SSR primers i.e. 0.85 whereas RAPD primers showed only 0.64. Hence the study of genetic diversity among M. oryzae isolates using RAPD primers was more useful than MGM primers. The RAPD analysis formed two main clusters at the Jaccard similarity coefficient of 0.50. This grouping revealed that, all the isolates were clustered in accordance of geographical location but not in the specificity of leaf blast and neck blast isolates, because all the neck blast isolates were clustered in all groups along with the leaf blast isolates. Mating type distribution of M. oryzae isolates was studied by using mating type specific SSR primers. Most of the isolates were proved as MAT1-1. We have identified 8 haplotype groups where, haplotype 2 was predominant (n=27) in the population. M. oryzae isolates were grouped into 8 haplotypes. Majority of the isolates (n=27) were under the Hap-2 group, found to be older haplotype with broad geographical distribution and quite older than other haplotypes as evidenced with its multiple connections with other haplotypes in the study area followed by Hap-4 (n=5) and Hap-1 (n=3) respectively. Haplotype 2 (Hp-2) has the broader genetic base in the entire study area with its swift distribution in the areas of Siddipet, Suryapet, Mehbubnagar, Karimnagar, Medak and Rangareddy. The broader genetic base of DNA sequence polymorphism analysis of Haplotypes was illustrated in the present study using PopART (Population Analysis Reticulate Tree). In the present investigation, Tajima’s D test (-2.660) Fu’s Fs statistics (2.931) supported presence of higher rare alleles in the population. To identify the diversity of the 14 avirulence genes, specific primer pairs were used in this study. The highest frequency of avirulent gene prominent in M. oryzae population was Avr Pi54 (97.5%) followed by Avr Pizt with (95%) and Avr Pi9 with (92.5%). The avirulent genes Avr Pik, ACE1, PWL2, Avr Pib, Avr Pii were able to amplify with a frequency of 90 per cent, 90 per cent, 80 per cent, 80 per cent and 17.5 per cent respectively. The avirulent genes with lowest prominence were PWL1, Avr Pita and Avr C039 with frequency of 7.5 per cent, 5 per cent and 5 per cent respectively. Five artificial inoculation methods, Spraying, smearing, cotton string, cotton wool and Injection were evaluated and out these, injection method gave 96.00 per cent PDI whereas, cotton wool method and string method showed 58 per cent PDI and 24 per cent PDI, respectively on HR 12 cultivar. In cross inoculation studies, a pool of isolates consists of two leaf blast isolates i.e., Mo-31, Mo-28 and two neck blast isolates i.e., Mo-3 and Mo-6 were used. The results indicated that all the isolates (both leaf and neck blast isolates) showed both leaf blast and neck blast infection. In cross inoculation studies on other cereal hosts the rice blast pathogen can infect ragi rather than wheat. In the present study, the interaction between 29 monogenic lines, carrying at least one major R gene, with 16 races commonly found. The monogenic lines carrying Piz5, Pi1, Pi2 and Pi54 provided broad spectrum resistance and their resistance frequencies were 62.5 per cent, 97.5 per cent, 97.5 per cent and 77.5 per cent respectively. The races of M. oryzae from Telangana were able to overcome 12 resistance genes (Pib, Piks, Pik, Pik-h, Pik-m, Pik-p, Pi1, Pi7(t), Pish, Pita, Pita-2, Pita-3 and Piz-t). This information is useful for development of durable resistant variety to blast disease in Telangana. In present investigation, non-chemical agents viz., neem oil, panchagavya, beejamrutham, vermiwash and buttermilk were tested against M. oryzae using Poisoned food technique. All the non-chemical agents at different concentrations were significantly superior to control in checking the mycelial growth of the fungus. Among the tested agents, panchagavya and neem oil showed 81.67 and 79.63 per cent inhibition of mycelium growth. The antagonistic microflora shown a antagonism percentage of 64.71 to 72.22 against M. oryzae under in vitro conditions, upon seed treatment they exhibited highest seed vigor index ranging from 1561.35 (B7) to 2183.68 (TAIK 1) when compared with control. Further, they were identified through internal transcribed spacer (ITS) and 16S rRNA gene sequences analysis for bacteria and fungi respectively and they were identified as Bacillus cereus, Bacillus xiamenensis, Bacillus subtilis and Trichoderma asperellum. Bio-efficacy tests were carried out in field conditions during the two consecutive years Kharif 2019-20 and Kharif 2021-22 by spraying different combinations of the non-chemical agents. From the two years data, the treatments T2 (Seed treatment with Beejamrutha+ Three foliar sprays of neem oil at 40, 60 DAT and panicle initiation) T5 (Seed treatment with T. asperellum + Three foliar spray of neem oil at 40, 60 DAT and panicle initiation) and T8 (Seed treatment with T. asperellum + Three foliar sprays of Panchagavya) were proved superior for control of blast disease with higher yield. The results showing significant improvement in the seedlings treated with different concentrations of non-chemical agents in terms of disease incidence reduction, lower AUDPC and lower r value during two consecutive yearsThesisItem Open Access STUDIES ON CHILLI (Capsicum annuum L.) VIRAL COMPLEX IN MAJOR CHILLI GROWING AREAS OF TELANGANA AND ITS MANAGEMENT(PROFFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY, 2022-07-02) Yamini Sousheel, N.; Bharati Bhat, N.Survey conducted in major chilli growing areas of Telangana viz., Warangal, Mahabubabad, Mulugu, Jayashankar Bhupalpally, Nagarkurnool and Khammam during Rabi 2019-20 and Rabi 2020-21 seasons revealed the natural occurrence of chilli viral complex in different mandals. In all the districts, the disease incidence ranged from 2 to 40 per cent being maximum in Khammam (41.59 per cent) followed by Warangal (32.80 per cent) and Mahabubabad (26.79 per cent) and minimum disease incidence of disease was recorded in Mulugu (19.18 per cent) and Nagarkurnool district (20.21 per cent). Severity of disease complex varied with the cultivars. Different types of symptoms viz., leaf curl, puckering, mosaic, shoe string and yellowing were observed in the fields surveyed. Occurrence of thrips was recorded in every field irrespective of cultivar grown and the season surveyed but comparatively the population was higher during Rabi 2019- 20 in different chilli growing areas of Telangana. Among them, Scirtothrips dorsalis was showing higher incidence during Rabi 2019-20 (24.25 per 5 terminals) than Rabi 2020-21 (20.75 per 5 terminals) followed by Frankliniella schultzei (19.5 per 5 terminals) during Rabi 2019 and 20 per 5 terminals during Rabi 2020-21 respectively. Whitefly population was also observed in all the fields surveyed, their population constituted between 4 to 20 whiteflies/plant (Rabi 2019-20) and 5 to15 whiteflies/plant (Rabi 2020-21). During both the years of study whitefly infestation was highest in Warangal (8.50 whiteflies/ plant; 6.53 whiteflies/plant) followed by Khammam (6.35 whiteflies/plant; 5.75 whiteflies/plant), Mahabubabad (7.25 whiteflies/plant; 5.26 whiteflies/plant), Jayashankar Bhupalpally (5.75 whiteflies/plant; 5.10 whiteflies/plant), Nagarkurnool (2.55 whiteflies/plant; 1.35 whiteflies/plant) and Mulugu (1.55 whiteflies/plant; 1.25 whiteflies/plant. It has been observed that there was not much difference in its occurrence in rainfed - direct sown and irrigated - transplanted crop grown in these districts surveyed. In the present study, twenty weed species were found in all the surveyed fields across locations, type of soils and seasons. Parthenium hysterophorus was found to be most prevalent in chilli fields surveyed and frequency of occurrence of P. hysterophorus was maximum (78 per cent) in all the six districts under survey over two years followed by Amaranthus tricolor, Cyperus rotundus, Portulaca oleracea, Tridax procumbens, Digitaria marginalis, Argemone mexicana, Phyllanthus niruri, Commelina bengalensis, Datura stramonium, Sida acuta and Cleome viscosa. DAC-ELISA was carried out using CMV antisera during Rabi 2019-20 and 2020-21, and results revealed that out of a total of 80 virus isolates collected from different fields of Telangana during Rabi 2019-20, 55 isolates tested positive in DAC ELISA tests. Results of Rabi 2020-21 revealed that out of 80 isolates tested, only 45 isolates were positive for CMV. PCR amplification techniques were used in the present study for the detection of leaf curl virus in the infected samples collected during survey. Upon amplification by PCR, 1000 bp size amplicon was obtained in 25 leaf curl infected chilli samples. Results confirmed the specific association of Gemini virus (ToLCV) is involved with the chilli viral complex. Similarly, during Rabi 2020-21 a total of 30 samples were subjected to PCR amplification using the specific primers. Upon amplification by PCR, 1000 bp size amplicon was obtained in 25 leaf curl infected samples. These results confirm the presence of leaf curl virus in the suspected samples. Electron microscopic studies of negatively stained purified and leaf dip preparations at 20,000X magnification revealed the presence of typical spherical particles with an average diameter falling in the range of 28-30 nm. The sap from leaf curl infected samples was partially purified and examined by transmission electron microscopy. Twinned and icosahedral virions about 20 nm in diameter were observed in the purified preparation, which were the typical morphology of virus particles in the genus Begomovirus. Infectivity assays revealed that many weed species in different families that commonly grow in or near chilli fields harbor the viruses. In most cases, the infected weeds were asymptomatic. Symptoms that could be associated with virus infection such as yellowing, leaf curling, and interveinal chlorosis were only observed in some species belonging to the genera of Amaranthus, Datura, Tridax, Parthenium and Euphorbia which tested positive. Twenty six plant species belonging to ten families were tested under artificial inoculation for their susceptibility to CMV and leaf curl under insect proof conditions. Out of twenty six species tested for their reaction to chilli mosaic and leaf curl viruses, eighteen species have expressed the visible symptoms. The host range studies clearly indicated that weed species occurring in chilli fields and in crop plants such as groundnut, cowpea, curcurbits etc. were found to be the most common CMV sources under field conditions. Appearance of CMV in fields, where no known sources of CMV in the vicinity due to the migratory aphids and thrips carrying and contributing to the long distance spread of the virus. Three different modules were formulated and tested for the integrated management of chilli viral complex at two different locations. The disease appeared in all the modules at 4 weeks after transplanting (WAT). In general, the disease incidence increased with the age of the plants and recorded maximum incidence at 9 WAT. The disease progress was gradual in all the modules and at all the periods of observation. However, per cent disease incidence (PDI) was maximum at 9 WAT and least at 4 WAT. Out of the three modules the disease incidence was significantly less in module 2 during both the years consecutively, which recorded 27.2 per cent during Rabi 2019- 20 and 25.2 per cent during Rabi 2020-21 respectively, which can be due to the treatments like spray of thiomethoxam@0.2g/l at 30, 45 and 60 days, barrier crop (fodder maize 3 rows), trap crop (marigold) and sticky traps. Where module-3 was least effective due to lack of treatments like trap crop, barrier crop and systemic insecticides. The correlation analysis for whitefly population with weather parameters during Rabi 2019-20 and 2020-21 indicated that there existed positive and significant correlation of whiteflies with minimum temperature, morning humidity and wind velocity; but negative correlation with evening relative humidity and sunshine hours. Regression analysis between whitefly population and weather parameters indicated that minimum temperature and wind velocity accounted for 39 and 46 per cent total variation in whitefly population in both the seasons respectively. A detailed study was made on the effect of the viral complex on the yield parameters and the data was recorded in different modules for both the seasons. There was significant reduction in plant height, pod per plant and also the length of the pods in different modules over the control. In the present study there was significant increase in the severity of the disease (viral complex) and there was corresponding decrease in the yield, yield attributes of the chilli crop. Further the disease complex also influenced the yield contributing factors by mainly reducing the number of the pods per plant and also the length of the pods. The results indicated that there was significant difference between the CBR of different modules in correspondence with the disease incidence which had remarkable influence on the yield and yield attributes hence on the CBR. The present investigation revealed that module 2 not only reduced the number of application of pesticides to cut down the cost of production but also enhanced the yield of fruits with improved benefit cost ratio.ThesisItem Open Access ENGINEERED GREEN PAINTS FOR COMMERCIAL TEXTILE PRINTING(PROFFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY, 2021-04-15) Lakshmi Pooja, S.; Padma, A.India is the country with rich biodiversity and traditional knowledge and skill to produce eco-friendly natural dyed textiles. India is also in the second place as the largest producer of textile products including handmade and industry processed. Recently, the textile wet processing industry is becoming famous not in terms of production or improved GDP, but in-terms of shut down due to the heavy pollution emission. As, textile wet processing units demands a heavy load on their ETP’s, the cost incurred in maintenance became a major concern to the industry and as well as to the government resulting in leaving a very high carbon foot print. The research is aimed at using all natural textile auxiliaries and pigments to produce bottled textile paints suitable for ready application on textiles. The textile auxiliaries selected are, two thickeners such as tamarind seed kernel powder and precipitated calcium carbonate; two resins such as cashew nut seed liquid and chitosan; two plasticizers such as cold pressed castor oil and linseed oil. They were tested for their substantively, finally a wet base consisting tamarind seed kernel powder (TSKP), castor oil (CO), cashew nut seed liquid (CNSL) were used for the study. Five natural dye sources were selected for the study including annatto seed, marigold flower, sappan heartwood, pomegranate rind and indigo. All natural dye sources were boiled in water as aqueous method except indigo to produce the liquid pigment. Indigo fermented pot liquor was used for the study. Textile paints in seven colours viz, yellow, orange, red, purple, indigo, green and black were produced from Name of the Author : Lakshmi Pooja Sanku I.D. No. : HHD/2016-009 Title of the Thesis : Engineered Green Paints for Commercial Textile Printing Degree to which it is submitted : Doctor of Philosophy in Home Science Major field : Textiles and Apparel Designing Faculty : Home Science Major Advisor : Dr. (Mrs.) A. Padma University : Professor Jayashankar Telangana State Agricultural University Year of Submission : 2020 liquid natural dye pigments along with base in combination of three mordants including alum, stannous chloride and ferrous sulphate. Three preservatives including cow urine, cow arku, sodium benzoate were used and their efficiency in improving the shelf life of the pigments for one year was studied, from which cow urine found to be the best preservative for pigments. The shelf life of paints in terms of microbial growth and packaging stability were tested using IS and ASTM standards. All paints prepared were printed on pre washed cotton, viscose rayon, silk and polyester plain woven fabrics using screen printing technique and the printed fabrics were treated with steam and vinegar washed for better fixation of pigment and to maintain the clear white background of the fabric. All the printed fabrics were evaluated for their geometrical and mechanical properties like yarn and fabric count, thickness, wickability, stiffness and tear strength. Colourfastness test methods for fastness to sunlight, washing dry and wet crocking and acidic and alkaline perspiration were also done by adopting AATCC, BIS, ASTM, JIS test procedures. The advance properties of the printed fabrics for their efficiency in UV protection and bacterial resistance were also tested following AS/NZS and AATCC test protocols. The effluents from the process was analysed for heavy metal content and oxygen demand in terms of COD and BOD3, which helped in testing developed paints for their eco-friendliness. Costing and consumer acceptance of the paints prepared and printed fabrics were studied respectively so as to check their commercial feasibility Therefore, engineered ‘green’ paints for commercial textile printing was a unique product, developed after analysing its attributes in terms of its end-use characteristics, environmental friendliness, quality checking, market feasibility, direct application, speed of production and consumer acceptability. In this study, all these aspects are satisfied in production of green paints for direct printing of natural and synthetic fabrics with natural dyes which itself is a unique product. With thorough research review, it was learnt that such organic paint product is not developed for commercial purpose so far. Therefore, the possibility of patenting the engineered natural pigment paint and the process will be explored through the use of developed paints and supply of raw materials. The research was focused on engineering an end to end product understanding the characteristics of various auxiliaries, pigments and effect of preservatives on them, developing an oil in water paint for textiles applications, analyzing the keeping quality of the paints developed and fabrics printed with them. Taking these things into concern the present study is aimed to engineer a product that can readily be used as textile paint with minimal effluent discharge without heavy metal content and reduced oxygen demand, without any volatile solvent resulting no air pollution. The product is also aimed at using natural raw materials so as to benefit the farmers and rural folk in cultivation or collection of raw materials. Having considered as green paints they open a huge export market too resulting in solving the major issues of concern for the survival of textile dyeing and printing industry. The developed paints can find a huge share in handmade textile industry too, as availability of natural dyes and auxiliaries to print or paint textiles, time incurred in preparation of natural colours and skill in developing fast colour became a major concern for once flourished craft from India.ThesisItem Open Access MOLECULAR CHARACTERIZATION OF BROWN PLANTHOPPER Nilaparvata lugens (Stål) POPULATIONS IN TELANGANA STATE AND IDENTIFICATION OF GENES FOR BPH RESISTANCE(PROFFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY, 2022-01-03) SUBHASHREE PRIYADARSHINI; JHANSI LAKSHMI, V.The present studies were conducted at ICAR-Indian Institute of Rice Research, Rajendranagar and Central Instrumentation Cell, College of Agriculture, Rajendranagar to study the spectrum of virulence, morphometrics, molecular characterization and clustering of brown planthopper (BPH) Nilaparvata lugens (Stål) (Delphacidae: Hemiptera) populations collected from Telangana state. Resistance sources were identified and characterization of resistance gene (s) for BPH in germplasm accessions was carried out. Mechanisms of resistance were studied in the selected rice gene differentials and germplasm accessions. A total of thirty two rice gene differentials with known and unknown genetics were evaluated for their resistance to nine brown planthopper populations collected from different districts of Telangana i.e., Adilabad, Khammam, Karimnagar, Mahbubnagar, Medak, Nalgonda, Nizamabad, Rangareddy, Warangal along with IIRR glasshouse population by adopting internationally accepted Standard Seedbox Screening Test (SSST) and scored on 0-9 scale by following the IRRI method of Standard Evaluation System (SES) for rice. Among thirty two rice gene differentials tested, 3 gene differentials viz., PTB 33, RP 2068-18-3-5 and RPBio4918-230S were categorized as resistant (DS 1.0 to 3.0), 13 as moderately susceptible (DS 5.1 to 7.0), 15 as susceptible (DS 7.1 to 8.9) and 1 gene differential as highly susceptible (DS 9.0) to brown planthopper populations. Among all the BPH populations, Medak BPH population was found highly virulent (DS 7.46) and least virulent was Mahbubnagar population (DS 6.34). In the resistant gene differentials, PTB 33 and RP 2068-18-3-5 the feeding was less in terms of low honeydew excretion and more number of probing marks suggesting antixenosis mechanism of resistance for feeding. Brown planthopper adults probed more number of times and fed more and excreted more honeydew compared to nymphs. The resistant gene differentials viz., RP 2068-18-3-5, RP BIO 4918-230S showed less nymphal survival (%), low growth index, highest proportion of males (%) indicating antibiosis mechanism of resistance. The sex ratio in most of the BPH populations was in favour of females. The proportion of macropterous adults was more than brachypterous adults in the BPH populations. The macropterous females emerged in more numbers compared to brachypterous females, macropterous males and brachypterous males. In general, the brachypterous females weighed more compared to macropterous females, macropterous males and brachypterous males. The gene differential, RP BIO 4918-230S revealed longest nymphal duration and more number of days to wilt indicating the antibiosis and tolerance mechanisms of resistance. The damage score has a positive correlation with fecundity, honeydew excretion and adult body weights. The damage score is negatively correlated with probing marks, days to wilting, nymphal duration, percent males and macropterous adults. Growth index has positive and significant correlation with nymphal survival. The measurements such as total length of the body, width of the body, length of wings, width of the wing, interocular distance, antennal length and tibial spur length of adult Brachypterous and macropterous forms of females and males were recorded. On an average Nalgonda BPH population showed highest body length, wing length, antennal length, interocular distance, length of tibial spur and highest rostrum length. Other morphological parameters i.e., body length and width, wing length and width, antennal length, interocular distance and length of tibial spur differed among different brown planthopper populations. When both genotypic and phenotypic clusters were compared, Adilabad & Warangal populations, Nalgonda & Khammam populations and Mahbubnagar & Nizamabad populations were found to be similar, whereas, Ranga Reddy & Medak and Karimnagar & IIRR glasshouse populations differed phenotypically and genotypically. Out of thousand germplasm accessions screened, one germplasm accession IC 518805 was highly resistant (DS 0.9), eleven germplasm accessions were resistant to brown planthopper with a damage score of 1.1-3.0. The brown planthopper adults fed less and excreted less honeydew on the germplasm accession i.e., IC 515974 (22.66 mm2 ). Nymphal honeydew was low 21.33 mm2 to 49 mm2 ) on resistant and moderately resistant entries viz., PTB 33, IC 576798, IC 519101, IC 517008 and IC 518849 compared to susceptible check. Fecundity and nymphal duration were less on resistant germplasm accessions compared to susceptible ones. In general, the sex ratio was in favour of females (1.22Females:1.0Males). In the germplasm accessions, the winged females were maximum in proportion (24.57%) followed by winged males (28.50%), wingless females (26.29%) and wingless males (20.63%). In general, the macropterous females weighed more (2.95 mg) compared to brachypterous females (2.89 mg), macropterous males (1.09 mg) and brachypterous males (1.05 mg). The number of days to wilt were more in the entries IC 519101, PTB 33, IC 75778 and IC 540340(A). Molecular profiling by using 17 SSR markers for detecting 9 BPH genes revealed that the germplasm accessions viz., IC 75883, IC 75887, IC 75778, IC 75886, IC 515880, IC 517008 and IC 515974 were observed to have Bph2 gene. The germplasm accessions viz., IC 575211, IC 75778, IC 75886, IC 75883, IC 515159, IC 515880, IC 540340(A), IC 200940, IC 517008 and IC 444008 were observed to have Bph3 gene. The germplasm accessions viz., IC 519101, IC 75883, IC 575211, IC 75887, IC 75778, IC 75886, IC 515159, IC 540340(A), IC 200940, IC 517008 and IC 515974 were observed to have Bph6 gene. The germplasm accessions viz., IC 75885, IC 515159 and IC 540340(A) have Bph17 gene. IC 519101 and IC 540340(A) were found to be have Bph20 gene. Among the germplasm accessions with different genes/gene combinations, Bph6+Bph20 (IC 519101), Bph2+Bph6 (IC 515974, IC 517008 and IC 75883), Bph2+Bph6+Bph17 (RP 2068-18-3-5 and RP 4918-230-S) and Bph32+Bph17 (PTB33) showed resistant reaction. The genes/gene combinations viz., Bph3+Bph6 (200940), Bph3+Bph17 (IC 75885) and Bph2+Bph3+Bph6 (IC 75886) showed moderately resistant reaction. The identified gene differentials and germplasm accessions can be used in the breeding programmes to develop brown planthopper resistant varieties.
