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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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    ThesisItemOpen Access
    TOTAL FACTOR PRODUCTIVITY AND SUPPLY RESPONSE OF MAJOR CROPS IN ANDHRA PRADESH
    (Acharya N.G. Ranga Agricultural University, 2018) DIVYA, K; BHAVANI DEVI, I
    The Present study entitled “Total factor productivity and supply response of major crops in Andhra Pradesh” was undertaken to study the productivity growth and acreage response of rice, maize, groundnut, cotton, sugarcane, bengalgram and redgram. Since these crops comprised of almost 50-60 per cent of the cultivated lands in the state. For the estimation of the cropping pattern and growth rates of area, production and yield of the selected crops, data was collected for the period from 1996-97 to 2015-16. The required data for this purpose was collected from various published documents of the Directorate of Economics and Statistics, Government of Andhra Pradesh. The selected period of study was from 1996-97 to 2014-15 for the estimation of total factor productivity (TFP) in the state. Data required for this purpose was collected from the published documents of the xv Cost of Cultivation scheme of Government of India and its website. The required data on the variables chosen as the determinants of TFP in the state were collected from various Statistical Year Books published by the Directorate of Economics and Statistics, Government of Andhra Pradesh. Data Envelopment Analysis (DEA) technique was employed to calculate and decompose the Malmquist TFP indices of the selected crops. DEA helped to decompose the TFP index into various efficiency measures. Multiple regression analysis was carried out by taking the TFP index of individual crop as dependent variable to determine the factors affecting the TFP growth in Andhra Pradesh state and ordinary least square adopted from nerlovian model was used to calculate the supply response for the major crops. The cropping pattern in the state was analysed in terms of the percentage of area under cultivation of the selected crops The gross cropped area in 1991-92 was 82.48 lakh ha while in 2014-15 it was 76.90 lakh ha. Rice was the main cultivated crop in the state in the year 1991-92 with a share of 26.07 per cent of total cultivated area, followed by groundnut (21.90 per cent), cotton (3.35 per cent), sugarcane (1.54 per cent), redgram (1.34 per cent), bengalgram (0.41 per cent) and maize (0.31 per cent). The growth rates of area, production and productivity are assessed in terms of annual compound growth rates (CAGR). Area under rice declined at an annual rate of 0.46 per cent, maize grew at a phenomenal annual rate of 16.39 per cent followed by bengalgram which too registered a very encouraging growth rate of 11.83 per cent. Cotton recorded a growth rate of 6.40 per cent annually. Redgram was another crop which recorded a production growth rate of above unity i.e., 1.85. Production of groundnut declined at an annual rate of 3.61 per cent. Sugarcane one of the important commercial crop grown in the state was observed to have a negative production growth rate of 0.96 per cent. Maize recorded the highest growth xvi rate of productivity with 4.57 per cent followed by cotton (3.73 per cent), bengalgram (2.08 per cent), rice (1.66 per cent) and redgram (1.58 per cent). The growth of all the inputs were in increasing trend except for the human labour and animal labour of all the selected crops from the base year to current year. The contribution of all the inputs are higher in all the selected crops except seed and animal labour inputs that was not impressive to contribute the huge percents to the total factor productivity growth in the state. The results for rice alone the MSP as percentage of cost A2 was 150 per cent during all the years of study, while it was 17 years of study each for maize and cotton, 14 years for sugarcane, 9 years out of 10 years in respect of bengalgram, 9 years in the case of redgram. MSP as percentage of cost C2 was maximum with 140.94 in one only year for rice and 145.82 per cent for cotton in year. Area effect was most responsible factor for an increase in production of sugarcane, groundnut, bengalgram and cotton. Yield effect was most responsible factor for increasing the production of rice and redgram. Increase in maize production was mainly due to interaction effect of area and yield. The decomposition of the TFPch for the corresponding years into EFFch and TECHch revealed that the increase in TFPch, which was due to the improvement in innovation (TECHch) for all the selected crops. The variables area under high yielding varieties and annual rainfall were significantly influencing the growth of TFP. The growth in total output index was higher than the growth in the total input index for rice, maize, groundnut, cotton and redgram. The total input index was highest for rice followed by groundnut, maize, bengalgram, cotton, sugarcane and redgram. xvii The estimates of instability in area, production and yield for major crops revealed that the production (44.29 %) and yield (35.92%) was highly unstable in the case of groundnut, area (32.63%) and production (41.37%) in cotton, production (34.39) in bengalgram and production (35.11%) in redgram was highly unstable. The area, production and yield of remaining crops i.e., rice, maize, sugarcane showed low instability. Acreage, production and yield response of crops were estimated and the results of the study period from 1996-97 to 2015-16 showed that the regression coefficients of the coefficient of lagged price and rainfall was in rice, lagged yield in the case of maize, lagged yield and rainfall in ground nut, rainfall and previous year’s area in cotton, lagged price and lagged area in sugarcane, lagged price, lagged yield and lagged area in bengalgram showed positive and significant influence on acreage. The regression coefficients of the previous year’s, lagged price and Irrigation in maize, rainfall in groundnut, price and rainfall in cotton, previous year’s production and irrigation in sugarcane, previous year’s production and rainfall in bengalgram showed positive and significant influence on production. The variables influencing yield were area under irrigation and lagged yield in rice, total rainfall in maize, total rainfall and lagged yield in groundnut, area under irrigation and lagged yield in cotton and total rainfall in bengalgram and redgram. The short run and long run elasticities of area response obtained from the regression coefficient of one year lagged prices was found to be less responsive to price changes of selected crops except for cotton and bengalgram. The short run and long run elasticities of production response obtained from the regression coefficient of one year lagged prices was found to be less responsive to price changes of selected crops except for maize and xviii cotton. The short run and long run elasticities of production response obtained from the regression coefficient of one year lagged prices was found to be less responsive to price changes of selected crops except for maize and cotton. The short run and long run elasticities of yield response obtained from the regression coefficient of one year lagged prices was found to be less responsive to price changes of all the selected crops. The coefficient of adjustment for rice, maize, groundnut, cotton and redgram was quicker for area response. The adjustment was quicker in the case of cotton and redgram for production response. The adjustment took less time in the case of sugarcane, bengalgram and redgram for yield response. The above mentioned crops indicated that the farmers took less number of years to realize 95 per cent of price effect.
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    ThesisItemOpen Access
    DESIGN AND DEVELOPMENT OF PROTOTYPE RIPENED CHILLI HARVESTER
    (Acharya N.G. Ranga Agricultural University, 2018) PRABHAKARA RAO, T; RAMANA, C
    India is the world’s largest producer, consumer and exporter of chilli. Chillies are cultivated mainly in tropical and sub-tropical countries like India, Japan, Mexico, Turkey, United states of America and African countries. Chilli is believed to have been introduced to India by Portuguese explorers at Goa in 17th century. The fruit of chilli plants have a variety of names depending on place and type. It is commonly called chilli pepper, red or green pepper, or sweet pepper in Britain, and typically just capsicum in Australian and Indian English. In Indian subcontinent, chillies are produced throughout the year. Two crops are produced in kharif and Rabi seasons in the country. Chilli grown best at 20–30°C temperatures, growth and yields suffer when temperatures exceed 30°C or drops below 15°C for extended periods. Now-a-days, cost of cultivation of chilli is increased day by day due to indiscriminate use of inputs like seeds, fertilizers and pesticides and also scarcity of labour. The major harvest season is between December-March with supply reaching peak levels in February-April. Planting is held mainly during August-October. Chilli cultivation needs more number of labourers for harvesting apart from the usual field operations such as sowing, weeding, pesticide applications, etc. as compared to other field crops. It is harvested (picking) 2 to 4 times and these harvestings are within a short span of time to get the quality produce, otherwise market price of chilli will be reduced. High cost and dearth of labour for hand harvest has resulted in increased chilli production cost declining even as consumption grows. Mechanization is only the way to reduce the cost of harvest and there by cost of production to make farmer comfortable with cost of harvest. The experimental set up was designed with two counter rotating double helical rollers of each length 200 cm and overall diameter 14 cm. The base frame was developed with the height of 100 cm, width of 85 cm and length of 160 cm to house the double helical rollers inside of the base frame. The rollers were fixed in the base frame inclined to the horizontal. The electrical motor was used as a prime mover to operate the double helical rollers at required speed for harvesting of ripens chilli pods. The experimental set up was tested to optimize the design parameters to get the maximum harvesting efficiency.The experimental unit of chilli harvester was fabricated to accommodate four different gaps between two rollers and four rotational speeds of counter rotating double helical rollers. The pulleys were changed on the double helical roller to get the four numbers of speeds like 289 rpm, 393 rpm, 484 rpm and 658 rpm by keeping constant pulley on power source. The four numbers of gaps were provided between the two rollers as 31cm, 32cm, 33cm and 340cm. The chilli harvester efficiency was calculated and varied from 29% to 31%. The harvesting efficiency of experimental set up was not in the acceptable range. The experimental set up was tested in all possible operating parameter combinations. The computed harvesting efficiency of machine observed at rollers speed of 289 rpm and rollers having gap of 320 mm was 9.41% at 2.0 km. h-1 forward speed. Likewise efficiency of machine at 330 mm gap of rollers was 9.97%, 14.00% efficiency was got at 340 mm space between rollers and 13.88% machine efficiency was observed at 350 mm gap between rollers with same 289 rpm of rollers speed with 2.0 km. h-1 forward speed. The roller speed was changed to 393 rpm and the computed resultant efficiencies of machine were 15.65%, 21.04%, 42.16% and 43.78% at rollers gap 320, 330, 340 and 350 mm respectively. The machine was run at 2.0 km. h-1 forward speed 481 rpm rollers speed with 320, 330, 340 and 350 mm space between rollers and computed efficiencies were 15.50%, 46.09%, 73.21% and 64.95% respectively. The efficiencies of machine at 658 rpm rollers speed with variable gaps between rollers 320, 330, 340 and 350 mm were 15.81%, 65.52%, 73.75% and 67.02%, respectively at same forward speed 2.0 km. h-1. In the similar way the machine was tested at 3.5 km. h-1 forward speed with variable gaps between rollers 320, 330, 340 and 350 mm at variable roller speeds 289, 393, 481 and 658 rpm respectively. The maximumefficiency 59.52% at rollers speed 658 rpm with gap 340 mm and minimum efficiency was observed 7.04% at 289 rpm rollers speed with gap between rollers 320 mm. The maximum mechanical damage of the harvested crop was 3.6%. The experimental set up was modified with regards power supply to double helical rollers, rotational speed and gap between the two rollers. The prototype ripened chilli harvester was fabricated with optimized design parameters and hitched to the high clearance tractor with help of two linkages. The power was transmitted to run the double helical rollers from the high clearance tractor PTO. The machine was evaluated in the farmers fields at Murikipadu village in Guntur district. The prototype harvester was operated with the optimized combinations of rollers speed and gap between two rollers like S1G1, S1G2, S1G3, S1G4, S2G1, S2G2, S2G3, S2G4, S3G1, S3G2, S3G3, S3G4, S4G1, S4G2, S4G3 and S4G4. The prototype chilli harvester was evaluated at each combination of rollers and the harvesting efficiency of prototype ripen chilli harvester was 72.08% at the speed 2.0 km. h-1 and roller gap of 340 mm. Thecalculated efficiencies were compared with existing practice of harvesting in manual harvesting. The labour required for harvesting of ripened chilli varied from 350 to 400 man.days per acreand approximate cost incurred for pickings was Rs.93750/- per acre whereas mechanical harvesting with developed machine was Rs.1567 per picking and for two pickings it is Rs.3134 per acre (Rs.7835/- per hectare). More importantly the labour saving was 98% and 2904 man hours when compared to manual harvesting.
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    ThesisItemOpen Access
    DESIGN AND DEVELOPMENT OF TRACTOR OPERATED GROUNDNUT COMBINE FOR HARVESTED CROP
    (Acharya N.G. Ranga Agricultural University, 2018) VENNELA, BASIREDDY; RAMANA, C
    Groundnut (Arachis hypogaea L.) is an important oilseed crop in India cultivated in an area of 6.7 million hectares with a production of 7.0 million tonnes annually. The crop can be grown successfully in areas receiving the rainfall ranging from 600 to 1250 mm. The best soils for groundnut crop are sandy loam, loam and medium black with a good drainage system. The present practice of manual harvesting and threshing consumes huge amount of labour to a magnitude of about 175 to 200 women h ha-1. It is very tedious and time consuming operation and is being adopted by for small scale farming. The manual method is the process of harvesting groundnut manually by hand, using expensive human labour. Since it is a labour intensive operation, scarcity of labour is often experienced during the peak harvesting season. One of the solution for reducing losses and dependency on human labour is to mechanize both harvesting and threshing simultaneously in groundnut cultivation. Several efficient independent machines are available for harvesting and threshing separately by manual feeding, but collecting harvested crop and feeding into thresher is again a labour intensive operation. Moreover, the harvesting requires maximum energy and combining may not be feasible with a commonly available tractor. Hence, the combine was developed by designing collecting, conveying and threshing systems for harvested groundnut crop. In this process, available machines like digger shaker and wet pod thresher were evaluated and synchronized the harvested quantity with the threshing ability of selected threshing mechanism. The tractor drawn groundnut digger shaker implement was tested in a total area of 0.27 hectares of sandy loam soil. Trials were carried out and the crop was sown with recommended row spacing 30 cm and 10 cm intra row spacing. The results revealed that plant height, plant width, root length, number of plants, number of pods per plant and number of filled and unfilled pods at the time of harvest was recorded as 35.8 cm, 17.53 cm, 25.27 cm, 27.12, 20.04 and 7.08 respectively. The highest average effective field capacity obtained using tractor drawn groundnut digger shaker was 0.35 ha h-1. The highest average field efficiency of 80.10% recorded for tractor drawn groundnut digger shaker at a soil moisture content of 12%. The haulm yield of the windrows formed for a harvested distance of 10 m was 1.011 kg for xv single row, 2.128 kg for two rows and 3.518 kg for three rows. Performance of wet pod thresher selected for a design was observed at a feed rate of 870 kg h-1 and the thresher output was 227.25 kg h-1 with the total number of the labours of 7. The designed collecting unit was provided with a rake angle of 600. The maximum conveying efficiency of the groundnut combine of 82.40% for the lateral conveyor was obtained at a combination of 1.19 ms-1 peripheral velocity of picker conveyor, forward speed of 1.59 km h-1 and 10 cm spacing of flaps. From the statistical interaction it was confirmed that the second speed of the prime mower i.e. 1.59 km h-1 is optimal for the collecting, conveying and hence the forward speed of the operation was fixed as 1.59 km h-1 for ensuring better collection. Similarly, the spacing of the flaps out of 5, 10 and 15 cm, the 10 cm spaced flaps gave best results in all independent trials with respective conveying of collected crop mass. Hence spacing between flaps designed to be 10 cm. The highest lateral conveying efficiency of 92.40% was obtained at a combination of Sf2-F2-Pv2 i.e. 10 cm - 1.59 km h-1- 1.19 ms-1 which confirmed for designed collecting mechanism. In the design of vertical elevator, the increase in slat spacing from 50 to 100 mm increased the conveying efficiency at all selected levels of peg end projections and peripheral velocity. The highest vertical conveying efficiency of 92.56% was obtained at a combination of S2-Pf2-Pv2 i.e. 10cm -1200- 1.19 ms-1, which confirmed results obtained during the trial. The performance of the developed combine for the harvested crop was observed that efficiency of the lateral and vertical conveyor was 92.40 and 92.56 respectively and the effective field capacity was 0.122 ha h-1 with an average fuel consumption of about 4.67 l h-1. The threshing efficiency of the developed groundnut combine was 82.54% compared to wet pod thresher because of slow feeding of the crop into the thresher from the trough. It was observed that the operation of groundnut combine resulted in 74.92 % saving in cost when compared to conventional method of manual collecting and hand stripping. It was also concluded that, the number of hours required for operating the developed combine harvester was 6.67 machine hours + 16 man hours which was least compared to treatment T3 conventional method of collecting and threshing was 200 h. As cost reduction between T1 and T2 were 1253.75 Rs ha-1 and 1370.94 Rs ha-1, the time required for collecting and threshing was more in T2 which is of 5.7 machine hours and 56 man hours, whereas for T1, it requires only 6.67 machine hours and 16 man hours. An overall saving of man hours from the developed machine was 92% and 71.42% over T3 and T2 respectively. It was observed that the output capacity of the thresher was 216.6 kg h-1 and the broken pod loss was 1.27%. The threshing capacity was 83.58% and the cleaning efficiency was 81.68%. The machine was tested in the experimental plot and field efficiency was found to be 76.72% with optimized design parameters at 1.59 km h-1 forward speed.
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    ThesisItemOpen Access
    DESIGN DEVELOPMENT AND PERFORMANCE EVALUATION OF PUNCH PLANTER FOR MAIZE IN RICE FALLOWS
    (Acharya N.G. Ranga Agricultural University, 2018) HARI BABU, B; JOSEPH REDDY, S
    Maize (Zea mays L.) is an important cereal food crop of the world with the highest production and productivity as compared to rice and wheat. It is the most versatile crop grown in more than 166 countries around the globe. During the year 2017-18, Andhra Pradesh ranked in 2nd in maize productivity in India.(Anonymous, 2018) Sowing is an important and time bound operation for crop cultivation. Early or delayed sowing adversely effects crop yield. The recommended seed rate has to be maintained by adopting adequate inter and intra row distance especially in maize crop. The crops grow uniformly if seeds are planted at uniform spacing. Thus, to obtain maximum yields, seeds should be planted at the desired spacing and in such a way all viable seeds germinate and emerge promptly To offer better seeding performance than conventional planters under no-till conditions a punch planter was developed which moves a minimum amount of soil and residue and offers precision in seed spacing. Minimal research has been carried to overcome limitations in punch planting concept, specifically making punches and simultaneously seed placement to obtain optimum population rate. The developed method of punch planting involves placing seeds into holes instead of furrows, which creates favorable environment for seed by providing good contact between seed and soil. The increase in use of mini tractors in all the states necessitated to design the technology for precision planting of maize to benefit the farming community. A mini tractor operated punch planter was designed and developed at College of Agricultural Engineering, Bapatla. It consisted of two major units with different components. The first unit was punching unit and second one seed placing unit. Punching unit draws power from tractor PTO and the main function is to punch holes in the field at a desired spacing and depth. The seed dropping unit is operated by punching rod and the main function is to drop single seed in the punches. The overall speed reduction ratios from engine to punch wheel were 22.61 and 15.53 for PTO lever position 1 and 2, respectively. In PTO lever position 1 and gear position 1, the forward speed of the tractor increased from 0.35 to 0.98 kmh-1 by increasing engine speed from 800 to 2400 rpm. In gear position 2 and 3, it was 0.80 to 1.53 kmh-1 and 1.69 to 3.28 kmh-1 , respectively. In PTO lever position 2 and gear position 1, the forward speed of the tractor increased from 0.35 to 0.99 kmh-1 by increasing the engine speed from 800 to 2400 rpm. In gear position 2 and 3 it was 0.85 to 1.68 kmh-1 and 1.75 to 3.50 kmh-1 , respectively. No effect of PTO lever position on forward speed of the tractor was observed. The mean punch spacings of 10, 16, 24, 35 and 53 cm were obtained in different gear and PTO lever positions. No significant effect on punch spacing in a particular gear and PTO lever position with forward speed of the tractor was observed. The punch spacings obtained in PTO lever position 1 and varying gear positions 1, 2 and 3 were 16, 24 and 53 cm, respectively. The punch spacings were obtained in PTO lever position 2 and varying gear positions 1,2 and 3 were 10, 16 and 35 cm, respectively. The required punch spacings can be obtained by selecting the gear and PTO lever position and the forward speed of the tractor can be maintained between 0.35 to 3.28 kmh-1. The seed miss index increased with the increase of punch planter speed in both punch spacings and also for two types of punch shapes. It was observed that in sandy clay loam soil, seed miss index was increased from 9.6 to 13.9% and 7.5 to 10.8% for 24 cm punch spacing and for type1 and type 2 punches, respectively, as the speed increased 0.8 to 1.7 kmh-1. In case of 16 cm punch spacing, it was observed that seed miss index was increased from 9.3 to 13.3% and 9.0 to 13.0% for type1 and type 2 punches, respectively, as the speed increased 0.8 to 1.7 kmh-1. The statistical analysis showed that there was a significant effect of interaction forward speed & type of punch and forward speed & punch spacing on index in both sandy clay loam and clay soil with rice fallow. decreased with the increase of punch planter speed in both punch spacings and also for two types of punches. I from 84.9 to 83.4% and 85.8 to 84.9% for 24 cm punch spacing and for type1 and type 2 punches, respectively, as spacing, it was observed that quality of feed index was decreased fro and 84.3 to 83.7% for type1 and type 2 punches respectively The theoretical field capacity was 0.1, 0.16 and 0.20 hah h-1 forward speed of operation efficiency were observed forward speeds of 0.8, 1.3 and 1.7 kmh obtained as 1.20, 1.48 and 2.14 Lh respectively. The total fixed cost with mini tractor and punch planter w 233.0/-, 18.0/- per hour with mini tractor was found to be and 66.0% in terms of manpower, time of operation and cost of operation due to use of punch planter than traditional manual sowing. Keywords: Punch planting emergence, field efficiency, operating cost. The quality of feed index In sandy clay loam soils, quality of feed index was decreased , speed increases from 0.8 to 1.7 kmh-1. For 16 cm punch from 84.0 to 83.1% respectively. hah-1 at 0.8, 1.3 and 1.7 km operations, respectively. The effective field capacity served to be 0.07, 0.12 and 0.15 hah-1 and 77.33, 74.25 and 75.33% at kmh-1, respectively. The fuel consumption was Lh-1 at operating speeds of 0.8, 1.3 and 1.7 kmh costs of sowing maize with developed prototype punch planter were 53.0/- and 35.0/- and variable cost hour, respectively. The total operating cost of the 339/- per hour. There was a saving of 50%, 58.3% % unch planting, seed dropping performance, reduction ratio, interactions seed multiple m he and field kmh-1, costs punch planter operation, respectively seedlings
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    ThesisItemOpen Access
    HYDRO-SOLUTE TRANSPORT MODELLING IN MOLE DRAINAGE SYSTEMS WITH SOIL OXYGENATION FOR CONTROL OF WATERLOGGING IN BLACK SOILS
    (Acharya N.G. Ranga Agricultural University, 2018) SAMBAIAH, ANGIREKULA; RAGHU BABU, MOVVA
    Sugarcane (Saccharum officinarum L.) is an important commercial crop with a production of 300 M t and 16 M t in India and Andhra Pradesh, with a productivity of 71.1 and 76.3 t ha-1 respectively. But the potential areas are withdrawn from sugarcane cultivation due to low yields ranging from 44 t ha-1 to 56 t ha-1 owing to the severe waterlogging problem in the present study area, Kapileswarapuram of East Godavari district, Andhra Pradesh. In this context, to solve this problem of waterlogging, an attempt has been made to intervene with a consortium of technologies viz., mole drainage systems and soil oxygenation to test the performance of sugarcane, model the mass and solute transport and evaluate economically for viability of the technology consortium. The scientific methods were followed to conduct pre-mole drainage investigations to find the soil characteristics, hydrological regime and groundwater table fluctuations and post drainage observations on soil, rainfall, runoff, preferential flow, drainage water, plant growth and yield attributes and economic analysis of the same. Extensive study of literature suggested that there is a minimal work conducted on mole drainage systems, as well as on soil oxygenation, that too in sugarcane, which is waterlogging sensitive crop, despite mole drainage system being very easy and low cost method of subsurface drainage and Calcium peroxide (soil oxygenation agent) being a harmless chemical, which releases oxygen in submerged conditions to the rootzone for about 14 weeks in the soil. Keeping the above points in view, the present study was undertaken to develop the consortium of technology to solve the problem of waterlogging in sugarcane. The soil texture of the study area is black soil with clay content of 52.87%, silt content of 33.25% and with sand content of 13.88%. This soil presented a bulk density of 1.15 g cm-3, with at plastic limit of 32.33%. The soil is slightly saline with ECe of 1.73 dSm-1 and pH of 7.89. The terrain of the experimental field was brought to 0.30% uniform xxii slope to avoid experimental bias and to facilitate grade to mole drains. The average saturated hydraulic conductivity of the study area soil profile is measured with auger hole method and found to be 0.30 m d-1(Pre-mole drainage) and 0.50 m d-1 (Post-mole drainage). The average depth of groundwater table is 0.30 m, b.g.l. Rainfall probability analysis revealed that the 1-day maximum rainfall event with 5-years return period is 157.0 mm which produces 101.4 mm of surface runoff and rest 55.60 mm abstraction into the soil, which upon moling, becomes drainage co-efficient for the mole drains. The SEW30 index for the study area is very high i.e. 2891.0 cm-days, double the sugarcane threshold limit. Using, the theory of Hooghoudt’s equation with additional assumptions for mole drainage spacing design, the mole drain spacing was designed to be 2 and 3 m and for sensitivity analysis purpose, 4 and 5 m spacing mole drains were also studied. The depth of mole drains were chosen to be placed at 0.4 and 0.5 m b.g.l as the 90% of the effective rootzone of sugarcane is found within 0.5 m below ground level. As an agent of soil oxygenation, calcium peroxide was chosen with an application rate of 2 g plant-1 placed at 15 cm b.g.l at midway between the plants. The experimental design selected is split-split plot design with four replications. Sugarcane variety of Co 86032 (Nayana) was selected for the study which has highest yield potential of 110.0 t ha-1, which is waterlogging sensitive variety. The seedling rate considered for the study is 25000 of seedlings ha-1 with paired row transplantation at a row to row spacing of 1.35 m and plant to plant spacing of 30 cm in zig-zag pattern. The maximum plant height at 305 DAS is 465.5 cm in 0.4 m depth mole drains with a mole drain spacing of 3 m under soil oxygenation treatment and 416.5 cm in 0.5 m mole drain depth plot with 2 m spacing with soil oxygenation, which is less than what was achieved in 0.4 m mole drain depth treatment. The average plant height in check plot WOSO (Farmer’s practice) was found to be 198.25 cm only. The sugarcane yield is the net effect of the all the treatments, which revealed that the average maximum yield of 108.92 t ha-1 was attained in 0.4 m mole drain depth with 3 m mole drain spacing and followed by 103.89 t ha-1 in 0.5 m mole drain depth with 2 m mole drain spacing and 3 m spacing in 0.5 m mole drain depth plots with soil oxygenation. In WOSO treatments, sugarcane yield of 93.08 and 92.74 t ha-1 was realised in in 0.4 m MDD - 3 m MDS and 0.5 m MDD - 2 m MDS respectively. The yield in check treatment under SO was found to be 64.60 t ha-1 and 57.91 t ha-1 in WOSO. The yield under the consortium of mole drainage and SO resulted in 88.0% more yield than check plot without soil oxygenation. The behaviour of the sugarcane yield in mole drainage systems has followed 3rd order polynomial equations in all the cases with highest co-efficient of determination ranging from 0.96 to 0.99. The total cost of mole drainage system installation was worked out to be ₹ 8,200.00, out of which, 44.0% cost goes into digging of the collector drain, 18.3% cost goes into outlet protection, 22.0% goes into actual mole plough operation. The expected life of mole drains is 3 years. The recurring cost for making moles from 4th year onwards will be only ₹ 2,300.00 for every three years, including the labour costs of ₹ 800.00 at 2016-17 prices. With the farmers practice in waterlogged soils, a loss of 16-22 paise on every rupee of investment is incurred despite the subsidy being given. In pre-drainage condition, the B:C ratio is 0.78, i.e. found to be below 1 and the net present worth is less than 0 (Negative), which infers that sugarcane cultivation in waterlogged vertisols is not a viable option to the farmers. To make it viable, either more subsidy is to be given or technologies are to be developed. In, 0.4 m mole drain depth installation, mole drainage systems with 2, 3, 4 and xxiii 5 m are found viable in consortium mode with soil oxygenation with a B:C ratio of 1.16, 1.22, 1.08 and 1.03 respectively and average IRR of 14.62%. Without soil oxygenation, only 2, 3 and 4 m are viable with B:C Ratio of 1.07, 1.13 and 1.03 respectively. But the maximum B:C ratio of 1.22 and 1.13 was achieved in 3 m spacing mole drains both in with soil oxygenation and without soil oxygenation. In 0.5 m mole drain depth installation, mole drainage systems with 2, 3 and 4 m are found viable in consortium mode with soil oxygenation with a B:C ratio of 1.19, 1.16 and 1.05 respectively with average IRR of 14.62%. Without soil oxygenation, only 2 and 3 m are viable with B:C ratio of 1.13 and 1.09 respectively. But the maximum B:C ratio was found in 2 m spacing mole drains both in with soil oxygenation and without soil oxygenation as 1.19 and 1.13 respectively. In conclusion, it can be said that the surface drainage co-efficient (overland flow) is found different from the mole drainage co-efficient (preferential flow of abstraction) and the new method adopted in the present study can be used in future. The mole drainage systems could handle larger drainage co-efficients such as 55.6 mm d-1 as in case of Kapileswarapuram. Hooghoudt’s equation was employed successfully for the design of mole drain spacing without considering the equivalent depth concept in this study. The hydraulic conductivity of the vertisol changed upon installation of mole drains from 0.3 to 0.5 m d-1 and bulk density decreased. Mole drains laid at 0.4 m depth with 2 and 3 m spacing could handle the maximum drainage flow depth of 46.1 mm d-1 of abstraction in 19.8 and 29.0 h respectively and the same was evacuated by 0.5 m depth with 2 and 3 m could in 24.4 and 35.7 h from the sugarcane fields. Soil oxygenation, a new concept studied using calcium peroxide granular powder placement in the sugarcane crop root zone proved successful in sugarcane and can be a component of consortium for mole drainage technology. Soil oxygenation agent (Calcium peroxide) did not cause any increase in soil salinity. The SEW30 index of the region was reduced from 2891 cm-days to 150 cm-days, which is far below the threshold limit of sugarcane crop. The mass and solute transport models developed and simulations using Hydrus-1D are useful for similar situations and regions. The mole drains at 0.4 m with 2 m and 3 m spacing could bring down the soil moisture to field capacity. Mole drainage systems along with soil oxygenation agents improved the oxygen reduction potential of the soil to +752 mV (Good aerated condition) from highly reduced conditions with -567 mV during heavy rainfall event. The mole drainage systems installed at 0.4 m depth at 2 and 3 m spacing could reduce the soil salinity by 65 and 50%, respectively. The mole drainage system installed at 0.5 m MDD at 2 m and 3 m spacing could reduce the soil salinity by 61 and 47% respectively. The sugarcane yield increased by 96.6% under mole drains installed at 3 m MDS at a depth of 0.4 m MDD along with soil oxygenation. The combination of mole drainage systems with soil oxygenation could bring up the BCR to 1.22 and NPW from negative to positive. Adoption of mole drainage systems with soil oxygenation using calcium peroxide granular powder provides 20-29 paise return on every rupee of investment in sugarcane. The models of mass and solute transport developed in the present study can be applied to similar situations encountered. New method for mole drainage design was developed by modifying the Hooghoudt’s assumptions. Another novel concept of low cost consortium of mole drainage with soil oxygenation is successfully experimented in waterlogged sugarcane vertisols and a new term “Draining capacity” is defined in the present study. Key words: Mole drainage, soil oxygenation, calcium peroxide, oxygen reduction potential, draining capacity, B:C ratio, Internal Rate of Return, Net Present Worth, SEW30 index, mole drainage co-efficient, waterlogging, salinity, Hydrus-1D.
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    ThesisItemOpen Access
    DETAILED SOIL RESOURCE INVENTORY OF BRAHMANAKOTKUR WATERSHED IN KURNOOL DISTRICT OF ANDHRA PRADESH USING REMOTE SENSING AND GIS
    (Acharya N.G. Ranga Agricultural University, 2018) SATISH, S; NAIDU, M.V.S.
    The present investigation involves “Detailed soil resource inventory of Brahmanakotkur watershed in Kurnool district of Andhra Pradesh using remote sensing and GIS”. For this purpose, twenty one typical pedons from Brahmanakotkur watershed were studied for their physical, physico-chemical and chemical properties. The area was characterized by semi-arid monsoonic climate with distinct summer, winter and rainy seasons. The pedons occurs in plains (P5, P6, P7, P15, P16, P17 and P18), very gently sloping (P1, P2, P3, P4, P8, P12, P13, P14, P19 and P20) and gently sloping (P9, P10, P11 and P21) topography. The P3, P5, P6, P7, P8, P11, P12, P13, P14, P15, P16, P17, P18 and P19 were developed from limestone whereas P1, P2, P4 and P10 were originated from dolomite. The P20 and P21 were developed from quartz while P9 was originated from shale. The morphological features indicated the presence of A-Bw-C (P4, P9 and P10), A-Bss-C (P1, P2, P3, P5, P6, P7, P8, P11, P12, P13, P14, P15, P16, P17, P18, P19 and P20) and A-C (P21) profiles. The soils were shallow to very deep in depth, very dark gray to strong brown in colour, gravelly sandy loam to clay in texture and exhibited sub-angular and angular blocky structures. xviii The clay content in P1, P4, P5, P10 and P21 exhibited an increasing trend with depth whereas no specific trend with depth was observed in remaining pedons. Physical constants like water holding capacity, loss on ignition and volume expansion followed the trend of clay content. COLE value in P3, P6, P17 and P20 exhibited an increasing trend with depth whereas P1, P4 and P5 showed a decreasing trend with depth. However, no specific trend with depth was observed in the remaining pedons. The soils of watershed were neutral to strongly alkaline (7.01 to 9.11) in reaction, non-saline (0.10 to 0.82 dSm-1) and low to medium (0.01 to 0.58 %) in organic carbon. The CaCO3 content in soils was ranging from 2.43 to 18.71 per cent and ESP was low to high (0.81 to 22.64 %). The CEC values were medium to high (18.60 to 61.72 cmol (p+) kg-1) and exchange complex was dominated by Ca2+ followed by Mg2+, Na+ and K+. The soils were low (37.63 to 188.16 kg ha-1) in available nitrogen, low to high (2.29 to 151.51 kg P2O5 ha-1) in available phosphorous and potassium (73.92 to 686.53 kg K2O ha-1) and deficient to sufficient (0.62 to 22.50 mg kg-1) in available sulphur. The soils were sufficient in DTPA extractable Cu and Mn and deficient to sufficient in DTPA extractable Zn and Fe. Based on CEC / clay ratio, physical, chemical and physico-chemical properties, the mineralogy class for P1, P2, P3, P4, P5, P6, P7, P8, P11, P12, P13, P14, P15, P16, P17, P18, P19 and P20 was smectitic while mineralogy class for P9, P10 and P21 was mixed. Based on the morphological, physical, physico-chemical, mineralogical and meteorological data, the soils were classified as Vertisols , Inceptisols and Entisols orders and these soils were classified at family level as: Pedons 1, 8, 11, 14 and 20 : Fine, smectitic, isohyperthermic, Typic Haplustert Pedon 2 : Fine-loamy, smectitic, isohyperthermic, Sodic Haplustert Pedons 3, 18 and 19 : Fine, smectitic, isohyperthermic, Typic Calciustert Pedon 4 : Fine-loamy, smectitic, isohyperthermic, Lithic Haplustept Pedon 5 : Fine, smectitic, isohyperthermic, Leptic Calciustert Pedons 6, 7, 12, 15, 16 and 17 : Fine, smectitic, isohyperthermic, Sodic Haplustert Pedon 9 : Fine-loamy, mixed, isohyperthermic, Typic Haplustept Pedon 10 : Loamy-skeletal, mixed, isohyperthermic, Typic Haplustept Pedon 13 : Fine, smectitic, isohyperthermic, Sodic Calciustert Pedon 21 : Loamy-skeletal, mixed, isohyperthermic, Lithic Ustorthent xix Twelve soil series were identified in the study area and were mapped into twelve different mapping units. The twelve mapping units were classified into five land capability sub-classes such as IIs (BRK2bB1g1D4, BRK5cB1g1D4, DGP4dA1g1D4 and PPLdA1g1D5), IIes (DGP2bC2g1D2), IIIs (BRK1dA1g1D5, BRK3dB1g1D5, BRK4cB1g1D1, BRK6cB1g1D5 and DGP1cA1g1D), IIIes (GGPaC2g2D2) and IVes (DGP3aC2g2D1). Similarly, the soils of watershed were grouped in to five land irrigability sub-classes namely, 2s (BRK2bB1g1D4, BRK5cB1g1D4, DGP4dA1g1D4 and PPLdA1g1D5), 2es (DGP2bC2g1D2), 3s (BRK1dA1g1D5, BRK3dB1g1D5, BRK6cB1g1D5 and DGP1cA1g1D3), 3es (BRK4cB1g1D1 and GGPaC2g2D2) and 4es (DGP3aC2g2D1). The soil-site suitability evaluation of the study area revealed that mapping units such as BRK1dA1g1D5, BRK3dB1g1D5, DGP1cA1g1D3, DGP2bC2g1D2, DGP3aC2g2D1 and GGPaC2g2D2 were not suitable (N) for growing rice crop whereas the mapping units like BRK2bB1g1D4, BRK4cB1g1D1, BRK5cB1g1D4, BRK6cB1g1D5, DGP4dA1g1D4 and PPLdA1g1D5 were marginally suitable (S3) for growing rice crop. All the mapping units were marginally suitable (S3) for growing maize and bengalgram crops except DGP3aC2g2D1 which was not suitable (N) for growing maize and bengalgram crops. The mapping units viz., BRK2bB1g1D4, BRK4cB1g1D1, BRK5cB1g1D4, BRK6cB1g1D5, DGP1cA1g1D3, DGP2bC2g1D2 and GGPaC2g2D2 were marginally suitable (S3) for growing sunflower crop whereas the mapping units such as BRK1dA1g1D5, BRK3dB1g1D5, DGP3aC2g2D1, DGP4dA1g1D4 and PPLdA1g1D5 were not suitable (N) for growing sunflower crop. Production potential revealed that, actual productivity of soil mapping units was poor, average and good whereas potential productivity of soil mapping units was good and excellent. The coefficient of improvement (Ci) varied from 1.59 to 3.42 indicating the implementation of judicious soil and water management practices to sustain crop productivity. Soil fertility maps were also prepared for watershed for various parameters such as pH, EC, organic carbon, available macronutrients (N, P2O5, K2O and S) and micronutrients (Zn, Fe, Cu and Mn) under GIS environment using ArcGIS 10.3 version. Comparison of satellite data collected during the year 2009 with that of satellite data collected during the year 2016, indicated that, the soil and water conservation structures in the watershed, increased the area under agriculture by decreasing the area under scrub land and canal dump which is further supported by an increase in the vegetation vigour and also NDVI values from negative to 1.
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    ThesisItemOpen Access
    STUDIES ON THE INTEGRATION OF CHEMICAL AND BIOLOGICAL METHODS FOR THE MANAGEMENT OF RICE STEM ROT DISEASE CAUSED BY Sclerotium oryzae Catt.
    (Acharya N.G. Ranga Agricultural University, 2018) RANGA RANI, ATLA; RAJAN, C.P.D.
    Stem rot of rice, caused by Sclerotia oryzae Catt. is a serious threat to rice production in India. Fungicides provide control of this pathogen but also have ill effects on the environment. In an attempt to develop better integrated strategies using fungicides and bacterial bio agents for management of stem rot disease, a total of eight isolates from different localities of Nellore district were isolated. The isolates of S. oryzae were designated as SO 1, SO 2, SO 3, SO 4, SO 5, SO 6 SO 7 and SO 8. Variability among these isolates of S. oryzae based on growth rate on PDA and also in utilizing various carbon sources was assessed using four different growth media. Depending on the growth rate on PDA medium, these isolates of S. oryzae could be categorised into four groups. Group 1 had the very fast growing isolate SO 3. Group 2 comprised of four isolates SO 1, SO 4, SO 6 and SO 7 which were fast growing. Group 3 consisted of the medium growing isolates i.e. SO 2, SO 8. Group 4 consisted of isolate SO 5 is very slow growing. Among the growth media tested, PDA was best supported for growth of all isolates and there was no growth of all the isolates of S. oryzae grown on CDA. Among the eight isolates, isolate SO 3 which was fast growing with abundant sclerotial production was selected for further studies. A total of thirteen antagonistic bacteria were isolated from rhizosphere soil of rice. Highest inhibition was recorded in case of RRB-2 (74.07%) followed by xiii RRB-4 with 70.73% inhibition, RRB-1 with 65.92% inhibition and RRB-3 with 62.22% inhibition. Least inhibition was observed with RRB-12 (31.84%) and with RRB-13 (33.31%). Four of these effective bacterial antagonists were used for further studies. Thirteen plant extracts, five plant essential oils and five natural preparation were tested for their bio efficacy against S. oryzae at different concentrations. The extract (powdered seeds) of Brassica juncea was found to be the most effective in inhibiting the growth of S. oryzae (100%) at 20 and 25% concentrations followed by rhizome extract of Curcuma longa (84.81) at 20% concentration, bulb extract of Allium sativum (84.44) at 2.0% concentration, leaf extract of Eucalyptus glubulus (76.29%). The bulb extract of Allium cepa recorded the least mean inhibition (4.40%) of S. oryzae at 5%. Out of the five essential oils, lemon grass oil showed 100 % inhibition of the test fungus at all tested concentrations. Spearmint oil at 1%, 1.5% and 2% concentrations and eucalyptus oil at 2% and 3% concentrations recorded 100% inhibition in the growth of S. oryzae. The mustard oil at 0.5% concentration recorded least inhibition (7.77%) followed by neem oil at 0.5% concentration with 19.25% inhibition in the growth of S. oryzae. Among the natural preparations, neemasthra was found to be the most effective in inhibiting the growth of S. oryzae (55.56%) followed by brahmasthra (49.66%), agniasthra (36.66%) and jeevamrutham (35.56). The neem seed kernel recorded the least mean inhibition (2.23%) of S. oryzae at 5000 ppm. Among the fifteen fungicides tested, Carbendazim, Propiconazole, Hexaconazole, Difenoconazole, Tebuconazole, Trifloxystrobin + Tebuconazole, Azoxystrobin, Isoprothiolane, Mancozeb + Carbendazim, Benomyl and Thiophanate-methyl completely (100%) inhibited the growth of S. oryzae at all concentrations in vitro. Thifluzamide (0.04%) recorded least per cent inhibition. Twelve fungicides were tested in vitro for the compatibility with potential biocontrol agents viz., RRB-1, RRB-2, RRB-3 and RRB-4. Isolate RRB-4 was found to be most compatible antagonistic bacteria as it has shown highest compatibility when compared to other isolates. Hexaconazole showed highest compatibility with all the four isolates followed by propiconazole. Effective fungicides and antagonistic bacterial isolates in in vitro studies were evaluated under field conditions. Results of pooled analysis of Rabi 2016-17 and early Kharif 2017-18 revealed that, among the fungicides, treatment Hexaconazole recorded lowest PDI. While among the bacterial antagonists, treatment Root dipping with RRB-4 + foliar spray showed less PDI after second spray. Hence, these two treatments were selected for further field trial during Rabi 2017-18 to evaluate the strategies involving the integration of effective fungicide and bacterial antagonist for the management of rice stem rot disease. Pooled analysis of the yield data revealed that the highest grain yield was recorded in Hexaconazole treatment (7.43 t/ha) followed by Difenoconazole (7.29 t/ha), Tebuconazole (7.19 t/ha), Root dipping with RRB-4+ foliar spray (6.97 t/ha), Carbendazim (6.91 t/ha) and Mancozeb + Carbendazim (6.89 t/ha). Least grain yield was xiv observed in untreated control (5.22t/ha) followed by Root dipping with RRB-3+ foliar spray (5.74 t/ha) which were statistically at par with each other. In case of straw yield, Hexaconazole treatment (7.22 t/ha) recorded highest straw yield followed by Difenoconazole; 6.88t/ha and Propiconazole; 6.84 t/ha which were statistically at par with each other. Least straw yield was observed in untreated control (5.47 t/ha). During Rabi 2017-18, the evaluation of the strategies of integration of effective fungicide Hexaconazole (0.2%) and the antagonistic isolate RRB-4, results revealed that, among the seven treatments consisting of different strategies, the following strategies were found superior. 1. Alternate sprays with hexaconazole and RRB-4 (40.00 PDI; 7.56 t/ha grain yield and 10.26t/ha straw yield). 2. Seedling dip with RRB-4 and two sprays followed by two sprays with hexaconazole (44.40 PDI, 6.95 t/ha grain yield and 8.53 t/ha straw yield). 3. Two sprays with hexaconazole followed by two sprays with RRB-4 (48.35 PDI, 7.37 t/ha grain yield and 7.73 t/ha straw yield).
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    ThesisItemOpen Access
    CHARACTERIZATION AND MANAGEMENT OF Alternaria porri (Ellis) Cif. CAUSING PURPLE LEAF BLOTCH OF ONION (Allium cepa L.)
    (Acharya N.G. Ranga Agricultural University, 2018) NAGA LAKSHMI, T; SARADA JAYALAKSHMI DEVI, R
    Purple leaf blotch caused by Alternaria porri is one of the most destructive diseases of onion causing significant bulb yield losses. Keeping in view the importance of disease, studies were conducted on cultural, morphological, pathological and molecular diversity, in vitro efficacy of fungicides and integrated management of disease at field by using fungicides and bioagents at Horticultural Research Station (HRS), Anantharajupeta. Survey was carried out to understand the disease severity in major onion growing areas i.e YSR Kadapa and Kurnool districts of Andhra Pradesh. Cultural and morphological characters of the native isolate were studied on six different media viz. Carrot agar, Corn meal agar, Czapek’s Dox agar, Host leaf extract agar Potato dextrose agar and Yeast extract agar medium. Out of all the media tested, growth was fast in Czapek Dox medium and slow in corn meal agar medium. Sporulation was best in Host leaf extract agar and potato dextrose agar and less in corn meal agar and Yeast extract agar medium. The pathogen produced septate mycelium. Conidiophores were produced either singly or in small groups. The conidiophores were straight or flexuous some times geniculate, septate, pale or mild brown in colour and measured upto 135μ long and 7-10 μ thick, with one to several conidial scars. xvii Conidia are straight or curved, rostrate, beak generally equal to the length of the body of the conidium pale brown to mild golden brown in colour. Overall length of the conidia ranged from 70-265 μ, 10-21 μ thick in the broadest part with 7-12 transverse and zero to six longitudinal septa, beak flexuous, pale 2-4 μ thick and tapering. A total of 15 Alternaria porri isolates were collected from different locations of Andhra Pradesh, Karnataka and Telangana. Later the isolates were identified and pathogenicity and virulence studies were conducted and found that leaves and the morphological character of the re-isolated organisms confirmed the pathogenicity. Among the isolates, Anantharajupeta (AP-1), Mydukur (AP-3), Gonegandla (AP-4) and Nandikotdur (AP-5) isolates were found highly virulent and potential with highest 41.67 to 56.58 PDI. Cultural and morphological characters of 15 isolates were studied. Conidial length of the isolates ranged from 23-170μ, with an average length of 96.5μ, width from 15-23μ, beak length ranging from 6-29μ and with beak width of 4-9μ. Colour from pale to mild golden brown, horizontal septa ranging from 3-13, with an average of 6-8 between isolates and vertical septa ranging from 0-5, with an average of 2-3 between isolates. Colony growth rate was fast in 8.14 mm in AP-1 and slow in 3.43 mm in KA-2 with an average growth rate of 5.74 mm per day among the fifteen isolates. Molecular characterization was done using 5.8s rDNA specific ITS1 and ITS4 primers. All the 15 isolates of A. porri yielded single PCR amplified product of 560 bp confirming the pathogen identity. Out of 15 isolates, five samples viz., AP-1, AP-4, AP-5, KA-2 and TS1 were sequenced and phylogenic tree was constructed and isolates were divided into two clades. Two groups AP-1 and AP-4; KA-2 and TS-1 were aligned in Clade I and AP-5 alone was grouped in clade II. Genetic diversity studies were carried out to assess the degree of genetic diversity/relatedness among 15 isolates of A. porri. Out of 10 SSR molecular markers used, only four SSR primers i.e., SSR-5 (115 bp) for KA-4, SSR-7 (215 bp) for KA-3, SSR-8 (250 and 340 bp) for AP-2 and SSR-10 (153, 237, 245 and 450 bp) for AP-6, AP-3, AP-6 and AP-4 respectively, produced unique bands. The PIC (Polymorphic Information Content) value ranged between ranged from 1.0 (SSR-1 and SSR 6) to 0.249 (SSR-1 and SSR-4) with an average of 0.826 for all 10 primers among the 15 isolates. In vitro screening of eight fungicides against native pathogen isolate revealed the efficacy of fungicides at varied levels. Hexaconazole was found effective and inhibited cent per cent growth at 1000 and 1500 ppm. Mancozeb was least effective and the mean inhibition per cent was 53.63 among the treatments. The highest toxicity index was observed in hexaconazole xviii (454.85) followed by propiconazole (431.05) on maximum toxicity index of 500. The least toxicity was 268.16 in the treatment of Mancozeb. In vivo evaluation of fungicides revealed that, hexaconazole at 0.1% with 12.50% of PDI and highest CB ratio (2.11) was found significantly superior over other treatments. Increased bulb yield over control and other treatments was observed in hexaconazole. Area under disease progress curve (AUDPC) calculated and yield (t/ha) data were also recorded. The data reveals that in T2 (Hexaconazole 0.2%), lowest AUDPC (399) was observed with highest yield (29.30 t/ha). While in control, highest AUDPC (1008) and lowest yield (9.67 t/ha). Fourteen fungal bioagents viz., Th-1, Tsp-2, Tsp-3, Th-4, Tsp-5, Tkn-6, Th-7, Tlb-8, Trs-9, Th-10, Tsp-11, Tsp-12, Tsp-13 and Tsp-14 comprising of Trichoderma harzianum, , T. koningii, T. reesii and T. longibrachiatum and six bacterial bioagents viz., P. fluorescens-1- Pf- 6 were evaluated against the pathogen and Th4 significantly superior in both in non volatiles (59.97%) and volatiles (57.325%) production over other Trichoderma isolates tested. Evaluation of 28 onion cultivars/ lines under two different agro-climatic conditions i,e., Anantharajupeta and Mahanandi to find the source of resistance, revealed that none of the genotypes was found to be either resistant or immune to the disease . However, the cultivars Bhima Super and Arka Kalyan showed moderately resistant reaction at both the locations. Management studies conducted over two seasons revealed that the integrated strategy with soil application of T.harzianum enriched FYM @ 100 kg/ha + seed treatment with T.harzianum @ 8g/kg of seed + two foliar sprays, one with liquid formulation of T.harzianum @ 5 ml/lt at first appearance of the disease followed by hexaconazole @ 0.2% at fortnightly interval was found significantly effective in reducing the disease intensity by recording a lowest PDI (14.09) with 79.69% disease reduction and yield 29.94 t/ha with 87.81% increased yield over control. This treatment recorded highest (1.99) cost benefit ratio, which was followed by tolerant variety Bhima Super (1.81).
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    ThesisItemOpen Access
    CHARACTERIZATION OF Pyricularia oryzae Cavara, INCITANT OF RICE BLAST AND ITS MANAGEMENT
    (Acharya N.G. Ranga Agricultural University, 2018) BHASKAR, B; SARADA JAYALAKSHMI DEVI, R
    The present investigation was undertaken with an aim to know the variability between leaf blast and neck blast pathogen populations. Studies carried out on the variability of isolates using cultural, morphological, pathological and molecular characteristics. In another study efforts were made to identify the promising lines for both leaf blast and neck blast resistance. Attempts were also made to manage the disease with biocontrol agent P. fluorescens, fungicides and their integration. Survey was conducted in nine major rice growing districts of Andhra Pradesh during 2015-16. The highest mean blast disease incidence 29.05% was recorded in Nellore district. The lowest mean PDI 20.79% was recorded in Srikakulam district. Regarding the mandals, highest mean blast incidence was recorded in Kovvur mandal of Nellore district with 38.99% in a range of 20.45% to 51.14%. The lowest incidence 15.41% with 10.94% to 21.02% range was noticed in Madugula mandal of Visakhapatnam district. The disease incidence was highly varied among the cultivars rather than the locations. The ascending order of the cultivars regarding the mean disease incidence was NDLR-8 (3%) < MTU-3626 (4.46%) < MTU-1121(5.89%) < NLR-34449 (11.09%) < RGL-2537 (12.86%) < MTU-1061 (16.83%) < MTU-1001 (19.74% ) < ADT-37 (23.81%)