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Acharya N G Ranga Agricultural University, Guntur
The Andhra Pradesh Agricultural University (APAU) was established on 12th June 1964 at Hyderabad.
The University was formally inaugurated on 20th March 1965 by Late Shri. Lal Bahadur Shastri, the then Hon`ble Prime Minister of India. Another significant milestone was the inauguration of the building programme of the university by Late Smt. Indira Gandhi,the then Hon`ble Prime Minister of India on 23rd June 1966.
The University was renamed as Acharya N. G. Ranga Agricultural University on 7th November 1996 in honour and memory of an outstanding parliamentarian Acharya Nayukulu Gogineni Ranga, who rendered remarkable selfless service for the cause of farmers and is regarded as an outstanding educationist, kisan leader and freedom fighter.
HISTORICAL MILESTONE
Acharya N. G. Ranga Agricultural University (ANGRAU) was established under the name of Andhra Pradesh Agricultural University (APAU) on the 12th of June 1964 through the APAU Act 1963. Later, it was renamed as Acharya N. G. Ranga Agricultural University on the 7th of November, 1996 in honour and memory of the noted Parliamentarian and Kisan Leader, Acharya N. G. Ranga. At the verge of completion of Golden Jubilee Year of the ANGRAU, it has given birth to a new State Agricultural University namely Prof. Jayashankar Telangana State Agricultural University with the bifurcation of the state of Andhra Pradesh as per the Andhra Pradesh Reorganization Act 2014. The ANGRAU at LAM, Guntur is serving the students and the farmers of 13 districts of new State of Andhra Pradesh with renewed interest and dedication.
Genesis of ANGRAU in service of the farmers
1926: The Royal Commission emphasized the need for a strong research base for agricultural development in the country...
1949: The Radhakrishnan Commission (1949) on University Education led to the establishment of Rural Universities for the overall development of agriculture and rural life in the country...
1955: First Joint Indo-American Team studied the status and future needs of agricultural education in the country...
1960: Second Joint Indo-American Team (1960) headed by Dr. M. S. Randhawa, the then Vice-President of Indian Council of Agricultural Research recommended specifically the establishment of Farm Universities and spelt out the basic objectives of these Universities as Institutional Autonomy, inclusion of Agriculture, Veterinary / Animal Husbandry and Home Science, Integration of Teaching, Research and Extension...
1963: The Andhra Pradesh Agricultural University (APAU) Act enacted...
June 12th 1964: Andhra Pradesh Agricultural University (APAU) was established at Hyderabad with Shri. O. Pulla Reddi, I.C.S. (Retired) was the first founder Vice-Chancellor of the University...
June 1964: Re-affilitation of Colleges of Agriculture and Veterinary Science, Hyderabad (estt. in 1961, affiliated to Osmania University), Agricultural College, Bapatla (estt. in 1945, affiliated to Andhra University), Sri Venkateswara Agricultural College, Tirupati and Andhra Veterinary College, Tirupati (estt. in 1961, affiliated to Sri Venkateswara University)...
20th March 1965: Formal inauguration of APAU by Late Shri. Lal Bahadur Shastri, the then Hon`ble Prime Minister of India...
1964-66: The report of the Second National Education Commission headed by Dr. D.S. Kothari, Chairman of the University Grants Commission stressed the need for establishing at least one Agricultural University in each Indian State...
23, June 1966: Inauguration of the Administrative building of the university by Late Smt. Indira Gandhi, the then Hon`ble Prime Minister of India...
July, 1966: Transfer of 41 Agricultural Research Stations, functioning under the Department of Agriculture...
May, 1967: Transfer of Four Research Stations of the Animal Husbandry Department...
7th November 1996: Renaming of University as Acharya N. G. Ranga Agricultural University in honour and memory of an outstanding parliamentarian Acharya Nayukulu Gogineni Ranga...
15th July 2005: Establishment of Sri Venkateswara Veterinary University (SVVU) bifurcating ANGRAU by Act 18 of 2005...
26th June 2007: Establishment of Andhra Pradesh Horticultural University (APHU) bifurcating ANGRAU by the Act 30 of 2007...
2nd June 2014 As per the Andhra Pradesh Reorganization Act 2014, ANGRAU is now...
serving the students and the farmers of 13 districts of new State of Andhra Pradesh with renewed interest and dedication...
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ThesisItem Open Access INFLUENCE OF POTASSIUM AND NICKEL NUTRITION ON WATER STATUS, BIOMASS PRODUCTION AND YIELD IN MAIZE UNDER HEAT STRESS(Acharya N G Ranga Agricultural University, Guntur, 2019) GOWTHAMI, P; ASHOKA RANI, YA study entitled influence of potassium and nickel nutrition on water status, biomass production and yield in maize under heat stress was carried out at Agricultural College Farm, Bapatla during rabi 2017-18 and 2018-19 in split plot design, with three dates of sowing (December 20, January 10 and January 30) as main plots and eight treatments viz., S1: 100% RDK (Control); S2: 125% RDK; S3: 1 kg Ni ha-1; S4: 2 kg Ni ha-1; S5: S1+S3; S6: S1+S4; S7: S2+S3; and S8: S2+S4 as subplots in three replications. From the findings of the experiment it was revealed that increased mean maximum and minimum temperatures creates a heat stress for late sown crops resulting in significant influence on growth, biomass production, water status, leaf associated parameters, biochemical parameters, yield and yield components. Application of potassium and nickel also significantly affected the recorded parameters. Plant height was reduced by 14.7 to 24.6 per cent during 2017-18 and 9.6 to 20.7 per cent during 2018-19 in late sown crops whereas application of potassium and nickel enhanced the plant height by 6.7 to 33.6 per cent during 2017-18 and 5.6 to 28.2 per cent during 2018-19. During both the years, reduction in leaf area due to heat stress ranged from 7.9 to 17.1 per cent and 9.4 to 16.4 per cent respectively and an enhancement of 7.4 to 35.2 per cent and 7.8 to 38.3 per cent respectively was recorded with nutrient treatments. December 20 sown crop had taken maximum number of days to 50 per cent tasseling and minimum for 50 per cent silking. In January 30 sown crop it was observed that 50 per cent tasseling was hastened and silking was delayed. xviii Application of potassium and nickel enhanced the days to 50 per cent tasseling and reduced the days to 50 per cent silking resulting in reduced anthesis silking interval. Drymatter partitioning and total drymatter was greatly influenced by dates of sowing, potassium and nickel application. Higher leaf drymatter was observed at 60 DAS with a reduction of 10.7 to 24.1 per cent during 2017-18 and 10.2 to 22.5 per cent during 2018-19 due to heat stress under delayed sowing. Application of potassium and nickel enhanced the leaf drymatter to an extent of 4.4 to 21.7 per cent during 2017-18 and 1.9 to 20.4 per cent during 2018-19. Stem drymatter was reduced by 9.0 to 18.9 per cent during 2017-18 and 4.1 to 8.1 per cent during 2018-19 due to heat stress in late sown crops. The application of potassium and nickel increased it from 4.3 to 20.9 per cent during 2017-18 and 5.3 to 21.0 per cent during 2018-19. Reduction in root drymatter under delayed sowing ranged from 12.0 to 24.7 per cent during 2017-18 and 9.0 to 20.6 per cent during 2018-19. The increment with potassium and nickel application ranged from 6.8 to 33.6 per cent during 2017-18 and 3.4 to 22.6 per cent during 2018-19. Reproductive parts drymatter reduced to an extent of 5.6 to 13.3 per cent during 2017-18 and 4.7 to 8.2 per cent during 2018-19 due to heat stress under delayed sowing and with potassium and nickel application it was enhanced by 6.5 to 30.9 percent during 2017-18 and 4.4 to 23.1 per cent during 2018-19. During both the years a reduction of 8.3 to 18.4 per cent and 6.6 to 11.9 per cent was recorded in TDM due to the increased temperatures with delayed sowing and an increment of 6.5 to 31.5 per cent and 4.9 to 24.6 per cent was obtained with the application of potassium and nickel. Heat stress under delayed sowing resulted in 4 to 10.8 percent reduction in RWC. Potassium and nickel application increased the leaf water status and restored the normal conditions. Soil and canopy temperature were increased with increased temperature. Hence higher temperatures were recorded in M3 and application of potassium and nickel reduced the temperatures with the lowest values recorded in S8. Photosynthetic rate was declined by 5.5 to 11.1 and 4.5 to 9.0 m mol CO2 m-2 s-1 during 2017-18 and 2018-19 respectively due to heat stress induced by delayed sowing. An enhancement of 1.9 to 9.5 and 1.7 to 10.9 m mol CO2 m-2 s-1 during 2017-18 and 2018-19 respectively was observed with potassium and nickel application. Similarly stomatal conductance, internal CO2 and transpiration rate were also reduced with high temperatures and enhanced to some extent with nutrient treatments. xix Delayed sowing resulted in reduction of CSI to an extent of 6.1 to 14.2 percent due to increased temperatures. Potassium and nickel application enhanced the CSI by 3.7 to 19.3 per cent. An enhancement in MII (7.4 to 14.7 %) was observed in late sown crops with the increased temperatures, whereas with the application of potassium and nickel MII decreased by 2.5 to 13.5 per cent. Proline content was increased with enhanced temperatures by 11.6 to 20.7 percent during 2017-18 and 13.3 to 20.8 per cent during 2018-19. Potassium and nickel increased the proline content by 3.7 to 17.6 per cent and 2.7 to 18.3 per cent during 2017-18 and 2018-19 respectively. Enhanced activity of SOD (0.4 to 1.0 U mg-1 protein) and peroxidase (2.6 to 8.5 U mg-1 protein) was observed in late sown crops with the raise in temperatures. Application of potassium and nickel also increased the SOD and peroxidase activity. Yield components as number of rows per cob, number of kernels per row, test weight except number of cobs per plant were significantly reduced with increased temperatures in late sown crops and enhanced to some extent by potassium and nickel application, resulting in yield reduction by 18.0 to 50.2 per cent during 2017-18 and 16.6 to 48.8 per cent during 2018-19 and increment among the nutrient treatments except in S3 and S4 by 6.6 to 30.0 per cent during 2017-18 and 6.2 to 28.4 per cent during 2018-19. HUE was lowered by 18.7 to 48.8 per cent during 2017-18 and 18.0 to 47.5 per cent during 2018-19 in late sown crops indicating M1 produced greater yield per each heat unit absorbed. Nutrient treatments enhanced it by 6.6 to 30.2 per cent during 2017-18 and 6.0 to 28.3 per cent during 2018-19. Among the yield based stress indices except SSI all other as RHI, STI, GMP, MP and YSI were more in M2 than M3. Among the potassium and nickel all other treatments except S3 and S4 enhanced the stress indices with the highest values in S8 and S3 the lowest with high SSI.ThesisItem Open Access STUDIES ON LEAF NUMBER INDEX (LNI) IN MAIZE (Zea mays L.)(ACHARYA N G RANGA AGRICULTURAL UNIVERSITY, GUNTUR, 2019) RAVI BABU, M; NARASIMHA RAO, K.L.An experiment entitled “Studies on leaf number index (LNI) in maize (Zea mays L.)” was under taken at the Agricultural College farm, Bapatla during two consecutive years of rabi 2016-17 and 2017-18. The crop growth stages of maize are dependent on various morphological, anatomical and physiological parameters. The basis for the variation in dry matter production and reproductive growth in relation to its foliage is less understood. The leaf growth that designates the physiological age of crop is more useful for crop improvement programmes. LNI is a tool to identify the exact time for the initiation of the reproductive stage by counting the number of leaves as the crop matures from vegetative stage to reproductive stage. So, the experiment was laid out in randomized block design with six maize hybrids viz., 900M Gold, DKC 9142, DKC 9120, DKC 9081, DKC 9042 and Pinnacle in four replications to identify the stage of reproductive growth in relation to the physical number of leaves on the stem, by calculating the leaf number index (LNI) corresponding to tassel and cob initiation and development. The observations were recorded for morphological, anatomical and physiological parameters at 7 days interval starting from 7 DAS. The results revealed that significant difference was observed among maize hybrids. Growing degree days (GDD) were measured for the crop growth seasons in 201617 and 2017-18, showed a gradual increase from 114.9 to 1447.5 and 141.6 to 1424.8 respectively from the 7 DAS till harvest. With the increase in GDD as the crop matures, plant height (12.43 to 274.5 cm and 11.88 to 268.75 cm), stem girth (0.21 to 2.84 cm and 019 to 2.88 cm), number of leaves per plant (3 to 16 in both the seasons) and LNI (20.31 to 100 % and 20.6 to 100 %) also showed a gradual increase in 2016-17 and 2017-18 respectively. Whereas, LAI showed an increase upto 70 DAS (0.05 to 5.68) during 201617 and till 63 DAS (0.04 to 5.65) during 2017-18 and then gradually decreased irrespective of GDD in both the seasons. During both the seasons, tassel primordial initiation coincided with the 9th visible leaf in 900 M Gold and DKC 9081, 10th visible leaf in DKC 9142 and Pinnacle and 11th visible leaf in DKC 9120 and DKC 9042 with LNI of 54.54, 54.54, 53.77, 52.79, 54.62 and 54.62 respectively in first season and 53.70, 54.71, 51.85, 53.70, 55.55 and 54.71 respectively in second season. Number of days to cob initiation in rabi 2016-17 was found less in DKC 9142 (32.25) followed by DKC 9120 (32.50), DKC 9042 (32.50) and Pinnacle (33.00) and high in other two hybrids 900M Gold and DKC 9081(43.75). In xvi second season it was 31.13 in DKC 9042, 32.00 in DKC 9142, 32.13 in Pinnacle, 32.63 in 900 M Gold and 34.00 in DKC 9081. All hybrids showed maximum level of chlorophyll (SCMR) at 63 DAS (first season) and 70 DAS (second season), high in Pinnacle and DKC 9142. This might be attributed to the LAI which was highest at 63 DAS and 70 DAS during 2016-17 and 2017-18 respectively. During rabi 2016-17 and 2017-18, DKC 9142 and Pinnacle recorded significantly higher photosynthetic rate and a sharp increase was noticed at 28 DAS. Higher net photosynthetic rate was recorded in maize hybrids at 70 DAS ranging from 37.80 to 39.95 (m mol CO2 m-2 s-1) but all hybrids were at a par. The physical number of the leaves on the stem were found to be 3 to 16 during both the seasons of the crop from 7 DAS until harvest. As the number of leaves increased, growth of the plant also showed significant changes with the rise of tassel and ear at 30 DAS and 33 DAS where the leaf number was 9 -11 during both the seasons. When the leaves on the stem are about 9-11, it readily indicates that the crop has entered the reproductive phase. Total dry matter highly accelerated at 63 DAS and DKC 9142 (220) recorded significantly more value. At 70 DAS, decreasing trend in stem, leaf, tassel and increasing in dry weight in cob and total dry matter was noticed in maize hybrids. Significantly higher dry weights were recorded by Pinnacle (116.00, 271.25) and DKC 9142 (115.52, 271.75) in respective cob and total dry matter at 77 DAS. Significant values were recorded by DKC 9142 and Pinnacle in root, cob and total dry matter (274.75 and 272.75) respectively. Dry matter partitioning of maize hybrids was different at different growth stages. Broadly it can be identified as four physiological stages i.e., vegetative stage (7 to 28 DAS), reproductive stage (28 to 42 DAS), grand growth stage (42 to 70 DAS) and physiologically mature stage (70 DAS to, harvest) where the dry matter varied from 0.4 to 5.4 and 0.31 to 5.63; 5.4 to 8.8 and 5.63 to 9.2; 8.8 to 274.75 and 9.2 to 266.3; 274.75 to 300.2 and 266.3 to 295 grams per plant during 2016-17 and 2017-18 respectively. CGR and NAR was found to be the highest at 57 to 63 DAS among all the hybrids during both the seasons where CGR was found to be the highest DKC 9142 followed by Pinnacle which were at par with each other. Whereas, pinnacle recorded highest NAR followed by DKC 9142. Among all the hybrids, RGR was found to be maximum at 50 to 56 DAS coinciding with reproductive primordial development. The yield and yield attributing characters such as length of the cob, number of rows per cob, number of kernels per row, 100 seed weight and the total kernel yield showed significant variation among the hybrids where the highest yield was obtained in pinnacle (9641.41 kg ha-1) and DKC 9142 (9243.9 kg ha-1). Leaf number index can be used as a tool to determine the correct stage to follow management practices within the crop which corresponds with the effective development of cob. A split dose application of nitrogen at 9 to 11th visible leaf stage is more effective corresponding to LNI ranging from 51.85 to 64.15 with a GDD of 488.7 instead of 3035 DAS which is regularly practiced, varied among the hybrids for better crop productivity. Pinnacle and DKC 9142 are recommended since they performed significantly better for all the various morphological, anatomical and physiological features of the crop.ThesisItem Open Access INFLUENCE OF GROWTH AND CANOPY ATTRIBUTES ON PRODUCTIVITY OF RAINFED GROUNDNUT(Acharya N G Ranga Agricultural University, Guntur, 2019) SREELATHA, P; SUDHAKAR, PThe experiment was conducted under rainfed conditions during kharif 2017 and 2018 in dryland farm, S.V Agricultural College, Tirupati with ten spanish bunch groundnut genotypes of three growth habits of erect (TCGS 894, TAG 24, K6, TMV2, Narayani), decumbent 2 (K9, Kadiri Amaravathi) and decumbent 3 (Dharani, TCGS1157, ICGS 76). Experiment was laid out in randomized block design and replicated thrice. The genotypes were evaluated for canopy attributes viz., plant height, internodal length, number of primary and secondary branches, angle of primary branch with main stem, leaf angle, leaf thickness and pubescence at various growth stages. Interrelation of these canopy attributes with canopy photosynthesis related traits, growth parameters and yield attributes were analyzed. Among the genotypes tested decumbent 3 and decumbent 2 growth habit genotypes recorded ideal range of canopy attributes viz., moderate plant height (36.18 to 36.64 cm), maximum number of primary branches (5.67 – 6.67 ) and secondary branches (5.83 – 6.61), wider angle between primary branch and main stem (81.79o – 86.90o) compared to erect growth habit genotypes. The data on canopy photosynthetic parameters revealed that maximum light was intercepted through the genotypes under decumbent-3 growth habit viz., Dharani (505.55 lux), TCGS 1157 (507.17 lux) followed by D-2 type K9 and Kadiri Amaravathi (432.30 lux). Whereas, lower light interception was recorded by erect genotype TCGS894 (162.67 lux). Similarly, D-3 type xvi Dharani recorded high radiation use efficiency (RUE) in terms of dry matter per unit amount of light interception (6.34 g MJ-1) followed by D-2 types K9 (4.72 g MJ-1) and Kadiri Amaravathi (4.96 g MJ-1). Erect growth habit genotypes recorded lower RUE viz., TCGS 894 (1.21 g MJ-1), Narayani (2.07 g MJ-1), TAG 24 (2.01 g MJ-1) and K6 (1.97 g MJ-1). Consequent to higher light interception and RUE, rate of photosynthesis was also higher in D-3 type Dharani (36.74 µ mol CO2 m-2 sec-1) followed by D-3 type TCGS 1157 (33.73 µ mol CO2 m-2 sec-1) and D-2 type K9 (33.25 µ mol CO2 m-2 sec-1). Mean values revealed that decumbent-3 growth habit types were superior in all photosynthetic attributes, followed by decumbent-2 at grand growth stage i.e. 60 DAS. Total drymatter was also higher in decumbent-3 growth habit genotypes viz., TCGS 1157 (52 g plant-1) followed by Dharani (45.55 g plant-1) and ICGS 76 (44.31 g plant-1). Maximum drymatter partitioning to pod is critical for achieving higher pod yield and decumbent growth habit genotypes TCGS1157 (51.26), K9 (51.26), ICGS76 (49.85), Dharani (47.71) and Kadiri Amaravathi (45.46) found superior than erect types. D-2 type Kadiri Amaravthi recorded higher critical LAI (5.39) followed by D-3 type TCGS 1157 (5.24). D-3 growth habit genotypes maintain higher physiological efficiency in terms of higher mean values of CGR, NAR and LAD throughout the crop growth, followed by D-2 and erect growth habit genotypes. D-3 growth habit genotypes also recorded moderate SLA (151.60 cm2 g-1) along with higher SCMR (44.78) followed by D-2 growth habit genotypes and erect growth habit types which denotes both decumbent types are efficient in maintaining higher WUE than erect types. Mean values of decumbent 3 and decumbent 2 growth habit genotypes recorded higher reproductive efficiency in terms of higher peg to pod ratio compared to erect types and higher yield attributing characters viz., higher number of filled pods per plant, maximum shelling percentage (> 45%) 100 sound kernel weight (> 65 g) and harvest index (46.6) compared to erect types. Consequently decumbent-3 type TCGS1157 recorded higher pod yield of 3760.77 kg ha-1 and it was on par with D-2 type Kadiri Amaravathi compared to best performance of mean of erect growth habit genotypes (2493.06 kg ha-1). The data on correlation studies revealed that plant height recorded significant negative correlation with peg to pod ratio. Number of secondary branches recorded significant positive correlation with rate of photosynthesis, leaf area, total drymatter, leaf area index, leaf area duration, SCMR, yield and yield attributes viz., number of pegs per plant, total filled pods, shelling percentage, 100 sound kernel weight, pod yield, harvest index. Primary branch angle with main stem recorded positive significant correlation with rate of photosynthesis, radiation use efficiency, light interception. Leaf area, xvii total drymatter, CGR, LAI, LAD. Yield and yield attributes viz., number of pegs per plant, total number of filled pods, shelling percentage, 100 sound kernel weight, pod yield. Among canopy attributes of groundnut number of secondary branches and primary branch angle showed to play pivotal role for higher physiological efficiency in groundnut. Based on canopy attributes and their correlation with growth, drymatter and yield characters in groundnut, the ideal plant type attributes for kharif rainfed conditions were described as follows. Medium plant height (35 – 40 cm), wider primary branch angle with main stem (80o to 86o), higher number of secondary branches (5 – 6), maximum critical leaf area index at peg to pod formation stage (4.5 to 5), moderate SLA (180-200 cm2 g-1) and high SCMR (45 – 50) for high WUE, high reproductive efficiency in terms of high peg to pod ratio (> 50), higher drymatter partitioning to pods (> 50%) at pod filling stage and crop duration of 100-110 days.ThesisItem Open Access CHARACTERIZATION OF BLACKGRAM (Vigna mungo (L.) Hepper) GENOTYPES FOR TOLERANCE TO YELLOW MOSAIC VIRUS (YMV) AND NUTRITIONAL INTERVENTIONS TO ENHANCE TOLERANCE(Acharya N.G. Ranga Agricultural University, 2018) RAJITHA, B; RAJA RAJESWARI, VA field experiment entitled “Characterization of blackgram (Vigna mungo L. Hepper) genotypes for tolerance to yellow mosaic virus (YMV) and nutritional interventions to enhance tolerance” was conducted at crop physiology laboratory (Lab study) and dryland farm (Field study), Sri Venkateswara Agricultural College, Tirupati. The blackgram genotypes (5 known tolerant + 5 known susceptible) obtained from Regional Agricultural Research Station, Lam farm, Guntur and Regional Agricultural Research Station, Tirupati were characterized under field conditions for YMV tolerance during rabi 2016-17 and summer 2017. Both susceptible and tolerant blackgram genotypes differed in their response to YMV infection in terms of morphological, physiological, biochemical, yield, nutrients and disease related characters. Among the five known tolerant blackgram genotypes, Cv. TBG-104 showed higher tolerance while Cv. LBG-623 was highly susceptible in five known susceptible group. Correlation studies revealed that significant negative relation of growth parameters and trichome density with percentage of disease incidence, whereas plant height and leaf lamina thickness established positive correlation. Based on results obtained a set of two blackgram genotypes i.e. one most susceptible (LBG-623) and other most tolerant (TBG- 104) genotypes were selected and laboratory experiment was conducted to identify safer Name of the Author : B. RAJITHA Title of the Thesis : CHARACTERIZATION OF BLACKGRAM (Vigna mungo (L.) Hepper) GENOTYPES FOR TOLERANCE TO YELLOW MOSAIC VIRUS (YMV) AND NUTRITIONAL INTERVENTIONS TO ENHANCE TOLERANCE Major Advisor : Dr. V. RAJA RAJESWARI Degree to which it is submitted : DOCTOR OF PHILOSOPHY Faculty : AGRICULTURE Major field : CROP PHYSIOLOGY University : ACHARYA N. G. RANGA AGRICULTURAL UNIVERSITY Year of submission : 2018 xxiv concentrations of nano scale oxide particles of Zn, Mg and Fe for blackgram through seed treatment. Among the various nano scale concentrations, nano scale Zinc Oxide @ 200 ppm, nano scale Magnesium Oxide @ 100 ppm and nano scale Iron Oxide @ 200 ppm recorded higher seedling vigour index (SVI) in terms of higher germination percentage and seedling growth in both the genotypes. These concentrations were selected for further evaluation of improving tolerance to yellow mosaic virus and yield under field condition. A field study was conducted during summer 2018 with two blackgram genotypes (TBG-104 and LBG-623) and nine treatments as foliar sprays including water spray control and replicated thrice in split-plot design. YMV infection was observed at 30 DAS. The foliar treatmental sprays were imposed at 30 and 50 DAS. Growth and physiological traits viz. plant height, leaf area, total drymatter, leaf area index (LAI) and leaf area duration (LAD), specific leaf weight (SLW) were found reduced in susceptible genotype (LBG-623) as compared to tolerant genotype (TBG-104) whereas leaf lamina thickness increased in susceptible genotype (LBG-623). Bulk and nano scale combined treatmental sprays and bulk MgSO4 @ 0.2% and nano scale Magnesium Oxide @ 100 ppm maintained significantly higher leaf area, dry matter and superior physiological traits viz., LAI, LAD and SLW and also greater SCMR compared to control. These treatmental sprays also recorded higher YMV tolerance interms of high SCMR, higher chlorophyll content, total phenols, total proteins, accumulation catalase enzyme, which denotes the efficiency of these treatments in enhancing YMV tolerance. Computing yield advantage and cost benefit ratio of foliar spray treatments for YMV tolerance, combined application of bulk ZnSO4 @ 0.2% + MgSO4 @ 0.2% + FeSO4 @ 0.2% recorded significantly higher B:C Ratio followed by nano scale Magnesium Oxide @ 100 ppm and combined application of nano sacle Zinc Oxide @ 200 ppm + Magnesium Oxide @ 100 ppm + Iron Oxide @ 200 ppm compared to control water spray. The present study revealed that, micronutrient foliar spray applications viz., combined application of nano scale Zinc Oxide @ 200 ppm + Magnesium Oxide @ 100 ppm + Iron Oxide @ 200 ppm, combined application of bulk ZnSO4 @ 0.2% + MgSO4 @ 0.2% + FeSO4 @ 0.2% and nano scale Magnesium Oxide @ 100 ppm were found superior in terms of YMV tolerance, morpho-physiological efficiency, nutrient content, biochemical, yield and yield components. Other treatments viz., nano scale Zinc Oxide @ 200 ppm, nano scale Iron Oxide @ 200 ppm and bulk FeSO4 @ 0.2% showed moderate performance. Hence, combined application of nano scale Zinc Oxide @ 200 ppm + Magnesium Oxide @ 100 ppm + Iron Oxide @ 200 ppm, followed by bulk ZnSO4 @ 0.2% + MgSO4 @ 0.2% + FeSO4 @ 0.2% were promising. Among the individual nutrient sprays, bulk MgSO4 @ 0.2% and nano scale Magnesium Oxide @ 100 ppm showed to play disease tolerance and minimized the incidence of YMV in blackgram.ThesisItem Open Access PHYSIOLOGICAL, BIOCHEMICAL AND MOLECULAR CHARACTERIZATION OF FINGER MILLET (Eleusine coracana L. Gaertn.) GENOTYPES FOR DROUGHT TOLERANCE(Acharya N.G. Ranga Agricultural University, 2018) PRANUSHA, P; RAJA RAJESWARI, VThe present investigation was carried out in the Indian Institute of Millet Research, Hyderabad to evaluate “Physiological, Biochemical and Molecular Characterization of Finger millet (Eleusine coracana L. Gaertn.) Genotypes for Drought Tolerance”. A field study was conducted with thirty finger millet genotypes, evaluated for drought tolerance in terms of higher physiological efficiency, drought tolerance capabilities and yield along with grain quality traits. The field experiment was conducted during Kharif, 2015 and Kharif, 2016. Field experiment was laid out in Randomized Block Design, replicated thrice and imposed moisture stress from panicle initiation to grain filling stage under rainout shelter during both years of experimentation. During this period morphological characters like plant height, leaf area, total dry matter, physiological parameters, SCMR, relative water content (RWC), chlorophyll stability index (CSI), gas exchange parameters were recorded periodically and yield related parameters were recorded at harvest. Under imposed moisture stress conditions morpho-physiological traits are significantly reduced compared to control, whereas proline (osmoregulant), super oxide dismutase and catalase (antioxidant enzymes) were increased. xvii The genotypes, GE-1013, GE-224, GE-1034 and GE-1028 maintained optimum leaf area, high dry matter, CGR, LAI and LAD compared to other entries and these genotypes also recorded high photosynthetic rate and WUE traits i.e moderate SLA and high SCMR, CSI, high proline accumulation and SOD enzyme activity and higher grain yield, which denotes the efficiency of these genotypes in conserving water as well as maintaining osmoregulation and better performance under moisture stress condition. Whereas GE-5112 and GE 156, GE-4004 and GE-390 recorded lower physiological attributes along with lower yield attributes denoting their susceptibility for drought. Genetic diversity studies with a set of 25 SSR markers revealed presence of variability among 30 finger millet genotypes. The number of alleles ranged from 1 to 7 with an average of 1.64 alleles. The mean values of observed heterozygosity and expected heterozygosity were 0.04 and 0.55. The average polymorphism information content was 0.07 in the present study. The 30 genotypes of finger millet were grouped into 6 clusters by UPGMA method, irrespective of geographical diversity, indicating no parallelism between geographic and genetic diversity. Clusters I, III and V formed solitary clusters revealed that presence of diversity for various characters among these genotypes. The genetic divergence analysis based on physiological attributes helps in providing valuable information in choosing the parents for hybridization for achieving higher yield. The variability existing in the finger millet genotypes provide opportunities for breeders to select specific donors for genetic improvement. The present study revealed that there is a sufficient genotypic variability among thirty finger millet genotypes for growth, drought tolerance, yield and its attributes. The genotypes GE-1034, GE-639 and GE-224, GE-1013 and GE-1028 were identified to be moisture stress tolerant genotypes in terms of physiological efficiency, osmotic regulation, yield and yield components. These genotypes can be used as donor source for crop improvement of drought tolerant finger millet genotypes through conventional or molecular breeding.ThesisItem Open Access INFLUENCE OF SILICON SOLUBILIZERS ON BLAST TOLERANCE, GROWTH, DEVELOPMENT AND YIELD IN RICE (Oryza sativa L.) GENOTYPES(Acharya N.G. Ranga Agricultural University, 2018) LAKSHMI PRASANNA, Y; RAJA RAJESWARI, VThe present investigation entitled “Influence of silicon solubilizers on blast tolerance, growth, development and yield in Rice (Oryza sativa L) Genotypes” was conducted at DRR farm (Indian Institute of Rice Research), Rajendranagar, Hyderabad, Telangana. The study conducted as two experiments and one experiment (Experiment I) was laid out during Kharif 2014 and 2015 in split plot design and replicated thrice with three main treatments control (T0), silixol @ 0.2% (T1), imidazole @ 0.05 % (T2) and eight sub treatments DRRH 3 (V1), PA 6129 (V2), PA 6201 (V3), PA 6444 (V4), PHB 71 (V5), BPT 5204 (V6), CO 39 (V7) and HR 12 (V8). An artificial blast screening nursery experiment (Experiment II) was conducted in Rabi 2014-2015, using blast susceptible genotype HR 12. Blast disease pressure was created by artificial inoculation. Pre infectional and post infectional spray of silicon solubilizers along with carbendazim were imposed. Another artificial blast screening nursery experiment (Experiment III) was laid out with eight rice genotypes during Rabi 2015-2016 and pre infectional and post infectional spray of silicon solubilizers were imposed. Crop response to silicon solubilizer treatments was measured in terms of morphological, physiological, biochemical, yield and its attributes and blast disease incidence. Among the silicon solubilizer treatments imidazole @ 0.05 % recorded significantly higher values for all these parameters except blast tolerance followed by silixol @ 0.2 % in both Kharif 2014 and Kharif 2015. xii Among the individual effects genotype PHB 71 showed significantly higher values for morphological, physiological, biochemical, yield and its attributes and lower blast disease incidence followed by PA 6129. PA 6201 and PA 6444 recorded moderate values for all these parameters and HR 12 and CO 39 recorded the lowest values for all these parameters. Data on different growth parameters viz., plant height, total dry matter revealed that imidazole @ 0.05 % recorded highest of all the above parameters compared to control and silixol @ 0.2 %. Among the genotypes HR 12 recorded highest plant height and total dry matter followed by PHB 71 and PA 6129. Data on tiller number, leaf area and leaf area index were significantly higher in the imidazole @ 0.05 % treatment compared to control. Among the genotypes PHB 71 and PA 6129 recorded highest tiller number and leaf area and lowest values were recorded for HR 12 followed by CO 39. Silicon solubilizer treatments significantly recorded the lowest no of days for 50 % flowering and maturity. The results indicated that the growth characteristics like CGR, RGR, NAR, SLA and LAD increased with the silicon solubilizers treatment due to increase in the leaf area and dry matter production. PHB 71 maintained higher CGR, SLA and LAD values followed by PA 6129 and PA 6201. The results of physiological parameters indicated that silicon solubilizers recorded high SCMR, total chlorophyll content and significantly increased the photosynthetic rate, stomatal conductance and maintained lower transpiration rate, leaf temperature. Imidazole @ 0.05 % treatment showed significantly higher values compared to silixol treatment @ 0.2 %. PHB 71 maintained higher photosynthetic values followed by PA 6129 and PA 6201 lowest values were recorded for HR 12 followed by CO 39. Data on the biochemical parameters indicated silicon solubilizers significantly increased the total chlorophyll content, silicilic acid content, total sugar content and phenol content. Imidazole @ 0.05 % treatment showed significantly higher values compared to silixol treatment @ 0.2%. PHB 71 maintained higher values followed by PA 6129 and PA 6201 lowest values were recorded for HR 12 followed by CO 39. Yield and its attributes i.e. number of panicles m-2, number of effective tillers hill-1, total grains panicle-1, filled grain panicle-1, grain yield kg ha-1, harvest index and test weight (g) were higher with Imidazole @ 0.05 % treatment followed by silixol treatment @ 0.2%. PHB 71 maintained higher yield attributes followed by PA 6129, PA 6201. Lowest values were recorded for HR 12, CO 39 recorded lowest values during both years of testing. xiii Highest incidence of blast disease in the field experiment (Experiment I) was observed in control which was 29.63 % followed by silixol @ 0.2 % treatment (23.61 %). The least Percentage disease index (PDI) was recorded in Imidazole treatment @ 0.05% (23.15 %). Among the genotypes HR 12 recorded highest PDI followed by CO 39 during both years of testing and lowest PDI was recorded for PA 6129, PHB 71 and PA 6201. Results of experiment II denotes that both the post infectional and pre infectional spray of different dosages of silicon solubilizers on HR 12 showed least PDI in carbendazim @ 0.2 % followed by silixol treatment @ 0.5 % and Imidazole @ 0.2 % treatment and highest PDI observed in control. Increased dosage of silicon solubilizers decreased the PDI for blast. Results of experiment III denotes that post infectional and pre infectional spray of silicon solubilizers on eight rice genotypes showed highest incidence of blast disease in control (T0) followed by silixol @ 0.2 % treatment and Imidazole treatment @ 0.05 %. Highest PDI was recorded in HR 12 followed by CO 39, BPT 5204, PA 6444 and DRRH 3 showed complete susceptibility to blast. PA 6201 and PA 6129 recorded lowest PDI and showed the resistance towards the blast disease and PHB 71 showed moderate resistance towards blast disease. More effectiveness of treatments was recorded in pre inoculation spray compared to post inoculational spray. Based on results obtained from the present study, it is evident that the Imidazole treatment @ 0.05 % proved effective among silicon solubilizer treatments in improving growth, physiological parameters. However significant effect in inducing blast tolerance in rice genotypes was not observed. Among the genotypes PHB 71 and PA 6129 were found effective for morphological, physiological efficiency, biochemical and yield attributes.ThesisItem Open Access SCREENING OF BLACKGRAM (Vigna mungo L. Hepper) GENOTYPES FOR PHYSIOLOGICAL EFFICIENCY AND DROUGHT TOLERANCE(Acharya N.G. Ranga Agricultural University, 2017) YOHAN, Y; SUDHAKAR, PThe experiment entitled “Screening of Blackgram (Vigna mungo L. Hepper) genotypes for Physiological efficiency and Drought tolerance” was conducted at crop physiology laboratory (Lab study) and dry land farm (Field study), S.V. Agricultural College, Tirupati. Forty five blackgram genotypes obtained from RARS, LAM, ANGARU were screened for heat tolerance using the standardized Thermo Induced Response (TIR) protocol, where seedlings were exposed to gradual and challenging temperatures in environment chamber. Among the 45 genotypes, top ten genotypes (KU-12-55, LBG-623, LBG-680, NDU-12-300, LBG-685, KU-12-14, LBG-645, KU-12-37, TBG-104, KU-12-13) having higher heat tolerance in terms of higher seedling survival and less reduction in root and shoot growth were selected along with two genotypes having lower heat tolerance viz., LBG-752, LBG-20. A field trail was conducted with two irrigation treatments (Control and stress) and 12 blackgram genotypes replicated thrice in split plot design. Moisture stress was created at pod formation stage i.e for a period of 15 days starting from 40 to 60 DAS. Sufficient moisture stress was created among stress treatments leaf relative water content was reduced by 25.2 per cent. xxii Morphological characters like plant height, number of nodules, leaf area, total dry matter, physiological parameters, drought tolerance traits viz., rooting abilities, Water Use Efficiency (WUE), Relative Water Content (RWC), chlorophyll Stability Index (CSI), Proline (Osmoregulant), Super oxide dismutase, Perioxidase (POD) (Antioxidant enzyme) and Nitrate reductase (NR) and yield related parameters were examined. Growth and physiological traits viz. plant height, crop growth rate (CGR), net assimilation rate (NAR), leaf area index (LAI) and leaf area duration (LAD), WUE traits (SLA, SCMR), other drought tolerant traits viz., CSI, RWC, yield and HI significantly reduced under moisture stress conditions compared to irrigated control, where as proline, POD and SOD were increased. The genotypes TBG-104, KU-12-13, KU-12-37 and LBG-623 maintained higher leaf area, dry matter and higher physiological traits viz., CGR, NAR, LAI and LAD compared to other entries under irrigated as well as stress conditions. These genotypes also recorded higher drought tolerance interms of WUE traits i.e moderate SLA and high SCMR, higher chloroplast stability (CSI), higher accumulation of proline and SOD enzyme, which denotes the efficiency of these genotypes in conserving water as well as maintaining osmoregulation and cell membranes integrity under drought condition. Genotypes TBG-104, KU-12-13 and KU-12-37 recorded higher mean root length and low root dry weight and hence maintained higher tissue water content compared to other genotypes. TBG-104, KU-12-13 and KU-12-55 which maintained higher growth, physiological and drought tolerance attributes also recorded higher HI, yield and its components followed by LBG-680, KU-12-37 and LBG-623. The genotype NDU-12-300, KU-12-14 and LBG 645 recorded lower yields under imposed moisture stress conditions as these genotypes recorded lower physiological attributes and drought susceptibility characters. TBG-104, KU-12-13 and KU-12-37 recorded lower percent yield loss in terms of higher drought tolerance index. The genotypes TBG-104, KU-12-13 and KU-12-55 were superior in terms of physiological efficiency, heat and moisture stress tolerance with high seed yield. These genotypes can be fit in rainfed cultivation or can be used as donor source for development of drought tolerant blackgram genotypes through conventional as well as molecular breedingThesisItem Open Access PHYSIOLOGICAL BASIS FOR DROUGHT TOLERANCE IN MAIZE (Zea mays L.) GENOTYPES(Acharya N.G. Ranga Agricultural University, 2017) RESHMA, A; RAJA RAJESWARI, VThe experiment entitled “Physiological basis for drought tolerance in Maize (Zea mays L.) genotypes was conducted at Crop Physiology Laboratory (Lab study) and dry land farm (Field study), S.V. Agricultural College, Tirupati. Thirty maize genotypes obtained from ARS, Peddapuram were screened for seedling traits such as germination percentage, root length, shoot length, seedling vigour index and coefficient of velocity of germination under laboratory conditions by imposing two levels of osmotic stress (-5 bar and -10 bar) using PEG-6000 against control. Germination percentage, seedling vigour index and coefficient of velocity of germination were decreased with increase in osmotic stress. Higher Seedling vigour index at -10 bar was observed in PDM 1452, PDM 1488, PDM 1474 and PDM 1465. Lower seedling vigour index was recorded in PDM 1439, PDM 14100, PDM 1401 and PDM 1430. Based on results obtained 12 genotypes were selected which includes ten tolerant and two susceptible genotypes. The selected genotypes were further investigated for drought tolerance and yield under imposed moisture stress field conditions during rabi 2015-16 and 2016-17. Moisture stress was created at soft dough growth stage i.e for a period of 20 days starting from 60 to 80 DAS. Morphological characters like plant height, leaf area, total dry matter, physiological parameters, drought tolerance traits viz., rooting abilities, water use efficiency (WUE), relative water content (RWC), chlorophyll stability index (CSI), relative membrane injury (RI), proline xxi (Osmoregulant), super oxide dismutase (Antioxidant enzyme) and yield related parameters were examined. Growth and physiological traits viz. plant height, crop growth rate (CGR), net assimilation rate (NAR), leaf area index (LAI) and leaf area duration (LAD), WUE traits (SLA, SCMR), other drought tolerant traits viz., CSI, RI, RWC, yield and HI significantly reduced under moisture stress conditions compared to irrigated control, whereas proline and SOD were increased. The genotypes, PDM 1452, PDM 1465 and PDM 1498 maintained higher leaf area, dry matter and higher physiological traits viz., CGR, NAR, LAI and LAD compared to other entries. These genotypes also recorded higher drought tolerance in terms of WUE traits i.e moderate SLA and high SCMR, higher CSI, lower RI, high proline accumulation and SOD enzyme activity, which denotes the efficiency of these genotypes in performing under drought condition. Genotypes PDM 1452, PDM 1428, PDM 1498 recorded higher mean root length and root dry weight and hence maintained higher tissue water content (RWC) to sustain cellular activities, whereas PDM 1439, PDM 1409 showed lower rooting abilities. PDM 1465, PDM 1452 and PDM 1498 which maintained higher growth, physiological and drought tolerance attributes recorded higher harvest index, yield and its components followed by PDM 1428 and PDM 1474. The genotype PDM 1439, PDM 1409 recorded lower yields under imposed moisture stress conditions as these genotypes recorded lower physiological attributes and drought susceptibility characters. PEG induced water stress method could be used as effective method for screening of maize genotypes for moisture stress tolerance as selected genotypes exhibited similar tolerance or susceptibility under field conditions. The present study reveals that moisture stress at soft dough stage is more sensitive. The genotypes PDM 1452, PDM 1465 and PDM 1498 are superior in terms of physiological efficiency, drought tolerance, yield and yield components. Hence these genotypes can be further tested in multilocation trials under rainfed condition before recommending to farmers. These genotypes are also valuable source for development of drought tolerant maize genotypes through conventional or molecular breeding.ThesisItem Open Access PHYSIOLOGICAL STUDIES ON HIGH TEMPERATURE TOLERANCE IN RICE (Oryza sativa)(Acharya N.G. Ranga Agricultural University, 2017) VERONICA, N; Dr. Y. ASHOKA RANIExperiment entitled “Physiological studies on high temperature tolerance in rice (Oryza sativa)” was conducted at ICAR- Indian Institute of Rice Research, Rajendranagar, Hyderabad during kharif 2014, rabi 2014-15, kharif 2015, rabi 2015-16. A set of 60 diverse rice germplasm were screened in kharif 2014 and rabi 2014- 15 for high temperature tolerance. The physiological traits based on which they were screend were membrane thermostability, chlorophyll fluorescence, paraquat tolerance assay, spikelet fertility, grain yield and yield based indices. Based on these genotypes both tolerant and susceptible to high temperature stress were identified. The cell membrane thermostability (MTS) reduced under high temperature by 23.1% over control. However under high temperature, genotypes N22 (80.5%), Rasi (78.9%), IR64 (69.8%), GSR330 (59.4%) and Akshayadhan (61.3%) had a higher MTS whereas it was lower in MTU1001 (20.5%), ADT43 (19.1%), Sumati (18.7%), Pantdhan12 (21.1%) and IR36 (22.4%). Chlorophyll fluorescence traits such as Fv/Fm (maximum quantum yield of PSII), electron transport rate (ETR), effective quantum yield (ΦPSII), co-efficient of photochemical quenching (qP) and co-efficient of non-photochemical quenching (qN) were reduced under high temperature conditions except for an increase in qN of some genotypes. The mean Fv/Fm reduced by 18.3% over control. The maximum Fv/Fm values under high temperature were noted in N22 (0.746), Rasi (0.734) and Khudaridhan (0.726) and minimum in NDR359 (0.335), RNR6378 (0.390) and MTU1001 (0.417). Lesser reduction in ETR was evident in N22 (5.0%), Sonkaichi (6.6%), Khudaridhan (8.6%), Akshayadhan (9.0%), Rasi (9.3%), Assanchidiya (10.5%) and IR64 (11.0%). On the other hand, higher reduction in ETR was in Mahamaya (76.1%), ADT49 (77.6%), MTU1001 (78.0%), ADT43 (78.0%) and WGL14 (79.7%). The ΦPSII under high temperature conditions was the highest in Rasi, N22 and Akshayadhan and the lowest in WGL14, ADT49, MTU1001 and Mahamaya. Paraquat treatment resulted in reduction in chlorophyll a, chlorophyll b and total chlorophyll content. Minimum reduction in the total chlorophyll content was noted in N22 (15.6%), IR64 (16.9%), BPT5204 (17.4%) and Rasi (17.4%). Maximum reduction was in Vandana (74.4%), Sugandhasamba (73.4%) and RPHR517 (64.6%). Regression analysis revealed that there existed a negative association between yield under high temperature and the per cent reduction in chlorophyll content. A reduction in all the yield components (number of panicles m-2, number of grains panicle-1, number of filled grains panicle-1, spikelet fertility, total dry matter, 1000 grain weight and harvest index) and grain yield with a subsequent increase in the number of unfilled grains panicle-1 in both kharif and rabi seasons was observed under high temperature. In both kharif 2014 and rabi 2014-15, maximum spikelet fertility under high temperature was recorded in N22, Rasi, Akshayadhan and IR64 and minimum in IR36, Vandana, ADT43, Sugandhasamba and Sumati. In kharif 2014, the grain yield under high temperature was maximum in N22 (5308.3 kg ha-1), Rasi (5133.3 kg ha-1), Assanchidiya (5083.3 kg ha-1), HKR47 (4816.7 kg ha-1) and TJP82 (4450.0 kg ha-1) and minimum was in Sumati (116.7 kg ha-1), Sugandhasamba (283.3 kg ha-1) and MTU1001 (400.0 kg ha-1). In rabi 2014-15 there was 26.8% reduction in grain yield under high temperature. Maximum yield under high temperature was in Rasi (6400 kg ha-1), Akshayadhan (6266.7 kg ha-1), HKR47 (6233.3 kg ha-1) and IR64 (6133.3 kg ha-1) and minimum was in ADT43 (2516.7 kg ha-1), Vandana (2866.7 kg ha-1) and NDR359 (3950.0 kg ha-1). Based on the grain yield in normal and in high temperature stress conditions, eleven yield based indices were computed and correlation analysis revealed that in kharif 2014, Stress Tolerance Index (STI), Geometric Mean Production (GMP), Mean Production (MP), Yield Index (YI) and Modified stress tolerance index (STIK2) had a significant correlation in both control and heat stress. In rabi 2014-15, besides the above indices Heat resistance index (HI) and Modified stress tolerance index (STIK1) also showed significant correlation. Hence these could be considered as suitable indices. The performance of the genotypes was assessed based on the above screening parameters and 4 genotypes (2 tolerant and 2 susceptible genotypes) were selected. Rasi and IR64 were selected as tolerant genotypes and MTU1001 and ADT43 as susceptible genotypes. N22 and Vandana were taken as tolerant and susceptible checks respectively. In-depth studies were carried out in kharif 2015 and rabi 2015-16 with the selected rice genotypes. Morpho-phenological parameters, physiological parameters, biochemical parameters, yield components and yield along with quality analysis were studied in these six genotypes. An increase in the mean plant height under high temperature in both vegetative and reproductive stages in both the seasons was observed. Tiller number m-2 and stem thickness reduced under high temperature in both the stages in kharif and rabi. Among the genotypes, the reduction was lesser in N22 and Rasi and higher in Vandana and MTU1001. In kharif and rabi the mean days to 50% flowering and days to physiological maturity reduced under high temperature. The shoot and root biomass at vegetative and reproductive stage and total dry matter at harvest reduced considerably due to the impact of high temperature. The mean total dry matter in kharif and rabi reduced by 27.2% and 40.5% respectively. High temperature resulted in the reduction of photosynthetic rate (PN). In kharif season, in both vegetative and reproductive stages higher PN under high temperature was noted in N22 (16.9 and 19.44 μmol [CO2] m-2 s-1 respectively) and Rasi (15.6 and 20.17 μmol [CO2] m-2 s-1 respectively). Lower PN in vegetative stage was in MTU1001 (11.07 μmol [CO2] m-2 s-1) and in reproductive stage in Vandana (13.27 μmol [CO2] m-2 s-1). Similarly in rabi also at both stages, N22 (15.55 and 21.18 μmol [CO2] m-2 s-1 respectively) and Rasi (15.12 and 20.78 μmol [CO2] m-2 s-1 respectively) maintained relatively higher photosynthetic rate under high temperature conditions. Lower PN was in Vandana (10.69 μmol [CO2] m-2 s-1) in vegetative stage and in MTU1001 (12.97 μmol [CO2] m-2 s-1) in reproductive stage. The stomatal conductance (gs) increased under high temperature in N22 and Rasi genotypes which led to subsequent increase in E under high temperature while both gs and E reduced in the susceptible genotypes. There was a reduction in Ci in all the genotypes but under high temperature higher Ci was noted in Rasi and N22. High temperature resulted in the reduction of Fv/Fm, ETR, ΦPSII and qP in all the tested rice genotypes. However the extent varied. The reduction in the observed fluorescence traits was higher in Vandana, MTU1001 and ADT43 and lower in N22 and Rasi. However, qN increased in all the genotypes under high temperature. The chlorophyll content reduced in response to high temperature in both the seasons at vegetative and reproductive stages. Reduction was less in N22 and Rasi and high in MTU1001, Vandana and ADT43. Pollen viability and stigma receptivity were affected due to high temperature stress. The mean pollen viability reduced by 28.3% over control. However, a higher pollen viability and a better stigma receptivity under high temperature was recorded in N22, Rasi and IR64 while, lesser pollen viability and poor stigma receptivity was seen in Vandana, ADT43 and MTU1001. Elevated levels of the leaf antioxidant enzymes, Superoxide dismutase (SOD), Peroxidase (POD) and Catalase (CAT) activity was noted in vegetative and reproductive stage in both the seasons. Higher SOD and CAT activity in reproductive stage was evident in N22 and Rasi. Imposition of high temperature stress significantly reduced the non-structural carbohydrates content in both the stem and leaf sheath. In kharif and rabi, under high temperature NSC’s in stem and leaf sheath was maximum in IR64 in both reproductive stage and at harvest. NSC’s in stem in kharif and rabi, in reproductive stage was minimum in Vandana and at harvest in N22. All the yield components and grain yield were reduced in the tested rice genotypes. A significant reduction in number of panicles m-2, panicle length, panicle weight, number of grains panicle-1, number of filled grains panicle-1, spikelet fertility, 1000 grain weight, grain yield and harvest index was noted in both the seasons. Higher spikelet fertility under high temperature condition in both kharif and rabi seasons was recorded in N22 (75.6 and 70.7% respectively) followed by Rasi (74.2 and 68.7% respectively). The lowest was noted in Vandana (27.5 and 19.03% respectively). The reduction in grain yield was lower in N22 and Rasi and higher in MTU1001. Quality parameters such as amylose content, gel consistency and gelatinization temperature were influenced by high temperature stress. Amylose content reduced in all the tested genotypes in both normal and chalky grains. There was an overall reduction in the GC of the tested rice genotypes. GT increased in Vandana and ADT43 and remained unchanged in other genotypes. A pot culture experiment was conducted to study the interaction of high temperature and water stress in 4 selected rice genotypes (N22, Rasi, Vandana and MTU1001). Plant height increased in response to high temperature (Ht), whereas reduced marginally in water stress treatment (Ws) and combined water stress and high temperature (Ht+Ws). Stem thickness reduced in response to stress and the reduction was maximum in MTU1001 and minimum in Rasi and N22. Compared to control, there was decrease in the number of days to 50% flowering and days to maturity under Ht and Ht+Ws. Shoot biomass and total dry matter reduced in Ws, Ht and Ht+Ws condition in all the genotypes. The extent of reduction in both the stages was higher under combined stress than the individual stresses. The reduction was higher in MTU1001 and lesser in N22 and Rasi. Significant reduction in the PN in both vegetative and reproductive stages in Ws (20.4 and 25.0% respectively), Ht (24.0 and 31.8% respectively) and Ht+Ws (51.8 and 52.3% respectively) was noted. In both the stages higher PN under stress conditions was in N22 and Rasi. gs and E reduced under Ws and Ht+Ws, however increased in N22 and Rasi under Ht conditions. Ci reduced in Ws, Ht and Ht+Ws. Fv/Fm, ETR, ΦPSII and qP reduced in both vegetative and reproductive stages under Ws, Ht and Ht+Ws; whereas qN increased. A higher Fv/Fm, ETR, ΦPSII and qP under stress was noted in N22 and Rasi. Chlorophyll content was also affected by Ws and Ht and the combined stress in all the genotypes at both the stages. The reduction in the total chlorophyll content at both the stages was higher in MTU1001 and Vandana and lower in N22 and Rasi. Relative water content (RWC) reduced drastically in both vegetative and reproductive stage under Ws and Ht+Ws and marginally under Ht. N22 and Rasi maintained a higher RWC under all the stress conditions. The proline content in both vegetative and reproductive stages, increased significantly under Ws (4.5 and 3.9 folds), Ht (2.4 and 2.9 folds) and under Ht+Ws (5.1 and 4.7 folds). Comparitively, N22 and Rasi maintained a higher proline content under stress conditions. Imposition of Ws, Ht and Ht+Ws led to reduction in all the yield components (panicle weight, number of grains panicle-1, filled grains panicle-1, spikelet fertility, 1000 grain weight and harvest index) and grain yield in Ws, Ht and Ht+Ws conditions. In Ws, Ht and Ht+Ws, higher spikelet fertility and lesser reduction in grain yield was in Rasi and N22 whereas lower spikelet fertility and higher reduction in grain yield was in MTU1001.