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Anand Agricultural University, Anand
Anand Agricultural University (AAU) was established in 2004 at Anand with the support of the Government of Gujarat, Act No.(Guj 5 of 2004) dated April 29, 2004. Caved out of the erstwhile Gujarat Agricultural University (GAU), the dream institution of Sardar Vallabhbhai Patel and Dr. K. M. Munshi, the AAU was set up to provide support to the farming community in three facets namely education, research and extension activities in Agriculture, Horticulture Engineering, product Processing and Home Science. At present there seven Colleges, seventeen Research Centers and six Extension Education Institute working in nine districts of Gujarat namely Ahmedabad, Anand, Dahod, Kheda, Panchmahal, Vadodara, Mahisagar, Botad and Chhotaudepur
AAU's activities have expanded to span newer commodity sectors such as soil health card, bio-diesel, medicinal plants apart from the mandatory ones like rice, maize, tobacco, vegetable crops, fruit crops, forage crops, animal breeding, nutrition and dairy products etc. the core of AAU's operating philosophy however, continues to create the partnership between the rural people and committed academic as the basic for sustainable rural development. In pursuing its various programmes AAU's overall mission is to promote sustainable growth and economic independence in rural society. AAU aims to do this through education, research and extension education. Thus, AAU works towards the empowerment of the farmers.
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ThesisItem Open Access STUDIES ON SOME ASPECTS OF PHYTO ETEOROLOGY OF WHEAT (Triticum aestivum L.) AT ANAND(AAU, Anand, 1985) SAVANI, M. B.; MISTRY, P. D.The changeability of meterological factors in time and space is diverse. The most important weather variables which have to be considered as limiting plant growth and development are temperature, moisture and light (or solar radiation). The distribution of these meteorological parameters during the growing season of the crop shows great variation in the different locations of the same region and consequently, a great variability in the crop production.ThesisItem Open Access STUDIES ON THE ASSESSMENT OF THE PERFORMANCE OF SOME CROP-WEATHER MODELS UNDER ANAND CONDITIONS(AAU, Anand, 1985) SHEKH, A. M.; MISTRY, P. D.Crop yield forecasting is quite important to monitor the economy of any country which is predominantly agricultural. Crop-weather Hodles are formulations which mathematically relate the crop yield with the agrometeorological parameters like evapotranspiration or crop transpiration (Tc). Very little information is available on the performance of available crop-weather models under the Indian conditions. With this background, a study was planned and conducted to test and validate the performance of different crop-weather models, during the rabi season of the years 1981-82, 1982-83 and 1983-84 with Sonalika (HDM-1553) variety of wheat. The evapotranspiration (ET) losses were measured by gravimetric soil moisture measurements which were termed actual evapotranspiration (AET) and were also estimated by Priestley-Taylor (1972) approach for obtaining potential evapotranspiration (PET).ThesisItem Open Access ENERGY BALANCE OVER A WHEAT FIELD WITH SPECIAL REFERENCE TO EVAPOTRANSPIRATION AND PHOTOSYNTHESIS(AAU, Anand, 1980) Mehta, Arvind N; MISTRY, P. D.Evapotranspiration and photosynthesis are among the most vital plant responses to energy that govern the productivity of crops in the field. The energy required for both the processes being derived from the net available energy over the field, a study of energy balance over a crop field is important in the understanding of the crop responses to weather. A field study to measure the energy balance components over the field of wheat, variety Sonalika (H.D.M. 1553) was carried out to estimate the energy utilization in evapotranspiration and photosynthesis and also to study other pertinent aspects of water use by crops.ThesisItem Open Access DYNAMIC MODELING OF DAILY WATER USE BY SUMMER PEARL MILLET ' (Pennisetum americanum L.)(AAU, Anand, 1995) Bodapati, Papuji Rao; Savani, M. B.Crop water use is a complex function of the climatic conditions, stage of the crop development and the soil water content. Models have been developed earlier using various approaches and levels of details to improve the prediction of evapotranspiration. Functional models with some empiricism can be used for routine applications than the mechanistic models. Transpiration from the pearl millet was found to be strongly influenced by leaf area than by stomatal conductance. Field experiments during the summer season of the years 1994 and 1995 were conducted with pearl millet cv. GHB-30. The experiments were laid out in split-plot design, with three dates of sowing as the main plot and four irrigation levels as the sub-plot treatments which were replicated four times. The results obtained in this investigation revealed that, air temperature had a profound influence on the growth and development of summer pearl millet. The optimum date of sowing was found to be February 15th , which would provide optimum environmental conditions for the growth and development of the crop. Different dates of sowing did not show any significant effect on the grain yield. Irrigating the crop at 25% depletion of available soil moisture gave the highest grain and biomass yields but its WUE was lower than that for the other irrigation levels. Pearl millet required about 310 GDD in summer season to build considerable GLAI and about 800 GDD to attain the maximum GLAI. A second-order polynomial was developed for estimating GLAI using the accumulated GDD. The FAO Kc, values had over-estimated ET rates and a second-order polynomial was developed to estimate daily Kc values from the accumulated GDD for non-stressed pearl millet. The rate of ET in pearl millet was found to decrease with an increase in soil moisture deficit and approached zero at a soil moisture depletion of 65% of the available soil moisture. PLANTGRO and MCD models when evaluated against the field data collected through this experiment, predicted ET reasonably better for nonstressed treatments than for stressed treatments. Of the two models, the MCD model predicted better for stressed condition than the PLANTGRO model. The functional relations for the PET estimation and root water uptake in the MCD model needed substantial modification. The separation of the PET in the PLANTGRO model did not suit the summer pearl millet. A one-day time step model BAJRAWAT had been developed in the 'C' language during the course of the present study, and was made User-friendly. Irrigation amount and the PET being its main driving forces, the partitioning of PET into soil evaporation and transpiration had been accomplished in BAJRAWAT by GLAI. The actual evaporation and transpiration depended on the availability of water in the surface soil and in the root zone and also on the depth of root penetration. The evaporation was assumed to take place from the surface soil only and the soil was further divided into four layers, from which water was assumed to have been removed by transpiration and drainage. Infiltration was assumed to have been taking place depending on the amount and the location of water already in the soil layers. The transpiration was computed as a function of GLAI and the available moisture in the root zone. The development of GLAI was considered to be controlled by thermal time and a moisture stress factor. The BAJRAWAT model when validated along with PLANTGRO and MCD models predicted ET better than the latter two models. The relative transpiration of summer pearl millet was found to be more closely associated with relative dry matter yield than with the relative grain yieldThesisItem Open Access CROP WEATHER RELATIONSHIPS IN SUMMER PEARL MILLET (Pennisetum americanum (L.) Leeke) AND TESTING OF CERES MILLET MODEL FOR THE MIDDLE GUJARAT AGROCLIMATIC ZONE(AAU, Anand, 1993) Maniyar, Vijayprakash Govindlalji; MEHTA, A. N.Pearl millet fPennisetum americanum (L.) Leeke) is one of the most important and widely cultivated cereal crop in the arid and semi-arid regions of the world. It is generally, grown as rainfed crop in rainy season in the scanty rainfall area and on poor soils. It is more resistant to drought than sorghum. It can sustain under higher temperature regimes. Under intensive cropping system, it has its own place and being cultivated during summer season, where irrigation facilities are available. Weather variables affect the crop growth differently in different phenophases during its growth cycle. Field experiments during summer season of 1991 and 1992 were conducted with Cv.GHB-30 and were laidout in split plot design, with three dates of sowing as main plot and four irrigation regimes as sub-plot, replicated thrice. The results obtained during the course of investigation revealed that, higher temperatures decreased the duration of the crop with the delay in sowing. Higher relative humidity during flowering stage gave higher grain yields. Higher grain yields were recorded from first date of sowing. However, reduction was lesser in second date of sowing. Late sown crop recorded lowest grain yields. Irrigation scheduled through IW/CPE = 1.0 proved best. However, irrigation scheduled by infrared thermometry could save about 30 to 35% of irrigation water with no much reduction in grain yields. Yield attribute such as earhead weight had positively contributed towards grain yield. Consumptive use of water increased with increase in the frequency of irrigation. However, water use efficiency was higher with lesser irrigation frequencies, indicating a drought resistance trait in summer pearl millet. Stress degree days had significant negative correlation with growth attributes. Decrease in leaf water potential during flowering stage had adversely affected the grain yields. Studies on Intercepted photosynthetic active radiation indicated higher IPAR use efficiencies in D2 treatment (15th Feb.sowing date) during both the years. The extinction coefficient (K) calculated showed a value of 0.89. Correlation studies between grain yield and weather parameters revealed that morning, afternoon and mean relative humidity upto flowering stage played a major role in deciding the final grain yield. During anthesis to dough stage both thermal interception rate (TIR) and intercepted photosynthetic active radiation (IPAR) showed significant positive correlation with grain yield indicating better source sink relationship. Stepwise regression analysis selected a model with mean relative humidity (during emergence to tillering stage) and hours of bright sunshine (during flag leaf to anthesis stage) as parameters for predicting grain yields, 20 to 25 days before maturity. Path analysis of grain yield and weather parameters observed in important phenophases indicated that higher relative humidity during flag leaf to dough stage and higher thermal interception rate (TIR) during anthesis to dough stage are found favourable for higher grain yields. Prediction model obtained for total biomass production selected only accumulated growing degree days (GDD) during emergence to tillering phase (P1). This model could predict the total biomass 50 to 60 days before maturity. CERES millet model corrected for genetic coefficients was found to be good for this region. CERES millet model could predict the anthesis date and maturity date with minimum error. However, grain yields and total biomass production predicted by CERES millet model showed larger percent error compared to that of grain yields and total biomass production predicted by regression models obtained in the study. Secondly, CERES millet model has the limitation of predicting the yield at the end of growing season. However, the prediction models obtained in the study could predict the grain yields and total biomass production well in advance.ThesisItem Open Access CROP WEATHER RELATIONSHIPS AND YIELD PREDICTION OF PIGEONPEA (Cajanus cajan (L.) MILLSP.) CV. GT-100 UNDER RAINFED CONDITION IN MIDDLE GUJARAT AGROCLIMATIC REGION(AAU, Anand, 1994) Khushu, M. K.; Mehta, A. N.Pigeonpea (Ca.ianus ca.ian (L.) Millsp.) is one of major grain legume crops in tropical and subtropical regions of India. It is generally grown as rainfed crop in scanty rainfall regions with minimum resources of water f0r irrigation. It is more drought resistant than any other field crop. It can sustain itself under higher temperature regimes. Since the effects of weather on yield are complex, need for a deeper and clear understanding of the climatic factors affecting the growth and yield of pigeonpea is necessary. The field experiments during Kharif seasons of 1992 and 1993 were conducted with Cv. GT-100 and laidout in randomised block design with four dates of sowing replicated five times. The results obtained during the course of study revealed that weather played a significant role in deciding the yield of pigeonpea. However, its variables affected the crop growth and yield differently in different phenophases during its growing period. The results regarding to the grain yield as well as total biomass of pigeonpea as influenced by dates of sowing showed that early sowing (D1) produced significantly higher grain yield as well total biomass, both of which decreased with delay in sowing. Similar trend was found in yield attributing characters, such as the number of pods per plant, seeds per pod and test weight as well as plant height. The favourable effects of early planting on crop growth and yield could be attributed to lower maximum temperatures in the phenophase from initiation of secondary branches %o flower bud initiation (P4) and higher night temperatures at pod setting phase (P6) in addition to higher vapoiir pressure, lower hours of bright sun shine throughout the growing season. The rainfall at flower bud initiation had also shown favourable effect in contributing to the higher yield of pigeonpea. Correlation of grain yield and total biomass with weather parameters and agrometeorological indices indicated that, besides the favourable effects of weather parameters discussed in the proceeding paragraph, the positive correlations of accumulated GDD and PTU in both vegetative period as well as flowering period in addition to accumulated PAR for entire period were found with grain yield and also with total biomass. The regression analysis between accumulated dry matter with accumulated PAR and accumulated GDD indicated that APAR use efficiency did not vary with the date of sowing while heat use efficiency did vary with the treatments. Path coefficient analysis revealed that rainfall in the phenophase P4, Min T and VP2 in the phenophase P6, Accu. GDD and Accu. PTU in the phenophase P8 and accumulated PAR in the phenophase P9 could be used efficiently in predicting grain yield of pigeonpea. Prediction models were developed by multiple regression technique for predicting grain yield. The model 4.6 based on RF in the phase P4, Min T and VP2 in the phenophase P6, accumulated GDD in the phenophase P8 and accumulated PAR "In the phenophase P9 with R2 = 0.95 was the best for predicting the grain yields at about 30 to 40 days before maturity. Standard partial regression coefficients provided relative importance of the parameters in predicting model and were in order VP2 (P6) Accu. GDD (P8). Min T (P6), RF (P4) and Accu. PAR (P9).ThesisItem Open Access WEATHER IN RELATION TO POTATO CROP (cv. Kufri Badshah JF-4870) IN MIDDLE AGROCLIMATIC ZONE OF GUJARAT(AAU, Anand, 1994) Saeed, Abker N.; Mehta, A. N.Field experiments were conducted during the rabi seasons of 1991-92 and 1992-93 in split plot design with three dates of planting as main plot and four irrigation regimes as sub - plot , replicated six times to understand the potato weather relationships and to assess with a high degree of certainty the optimum date of planting and appropriate irrigation regime for potato (cv. Kufri Badshsh JF-4780) on weather-based considerations . Water utilization pattern of the crop as well as the efficiency of infra - red (IR) thermometry in scheduling irrigation were also studied. The results obtained during the course of the investigation revealed that planting date had a significant effect on emergence, crop growth, crop duration and yield. There was a progressive delay in days to 50 % emergence with early planting due to higher temperatures . A mean air temperature of about 22°C after planting and/or a mean soil temperature ranging between 24' to 25.2"C as measured at 5 cm depth was found to be optimum for satisfactory lush emergence. The crop had maturity periods ranging from 101 days to 108 days and 92 days to 98 days after planting in the years 1991-92 and 1992-93 respectively. Higher tuber yield in optimum planting date (30 November) was due to relatively high values of leaf area index (LAI), crop growth rate (CGR) and number of tubers per m2. The adverse effects of early planting on crop growth and yield could be attributed to comparative high temperatures during emergence and comparative low temperatures during tuber bulking stages. The response of higher supply of moisture under treatment I1 to increased tuber yield and total biomass production was poor as compared to that under relatively lower supply of moisture under treatment I3. The increased yields produced under treatments I1 and I3 over those under treatments I2 and I4 were not quite pronounced indicating that scheduling of irrigation when ASM reached a value of 50 % of the total ASM (treatment I2) or with infrared (IR) thermometry with (Tc-Ta) ranging between ±_ 1 degree C (treatment I4) was satisfactory for obtaining high yield. This could save about 33 to 44 per cent of irrigation water without appreciable reduction in yields. There was a decrease in WUE with increasing irrigation frequency. The sensitivity of the potato crop to water stress was found to be determined by the total number of tubers rather than the tuber size. The results of SDD indicated that SDD accumulated over the period from early vegetative phase and tuber initiation to the end of vegetative phase and tuber development exhibited highly significant negative correlation with tuber yield as well as total biomass. The regression analysis indicated higher APAR use efficiency for D3I1 and D3I3 in both the years. For pooled analysis, the APAR use efficiency was 4.313 g MJ-1 Correlation of tuber yield as well as total biomass with weather parameters and agrometeorological indices studied ,indicated the favourable effect of low soil and air temperatures during tuber initiation and vegetative growth and comparatively higher temperatures during tuber bulking stage for higher tuber yield. Positive Correlation of accumulated GDD, HTU and ST with tuber yield indicated the indirect contribution of these indices to the tuber yield through the external morphological development of the potato crop. Path coefficient analysis revealed that min. T in the stage R1, Accu. APAR in the stage (R1 + R2) and Accu. GDD in the stage R3 could be used efficiently in predicting tuber yield. Highest contribution of LAI at 70 DAP (0.661) to tuber yield at 90 DAP suggested an advantage in selection of genotype that has the characteristic of maintaining high leaf area upto 70 DAP for better tuber yields of the potato crop. Prediction models were developed by using standard partial regression technique for predicting tuber yield. The model 4.9 based on min. T in the stage Ri , Accu. APAR in the stage (R1 + R2) and Accu. GDD in the stage R3 with R2 = 0.914 was the best for predicting the potato yields at about 20 to 30 days before maturity.ThesisItem Open Access CROP-WEATHER RELATIONSHIP IN RABI MAIZE (Zea mays L.) AND TESTING OF CERES MAIZE MODEL FOR THE MIDDLE GUJARAT AGROCLIMATIC ZONE(AAU, Anand, 1992) Reddy, D. Raji; Mehta, A. N.Maize (Zea mays L.) is one of the most important cereals both for human and animal consumption. Maize is grown in climates ranging from temperate to tropics during the period when mean daily temperatures are above 15 c and frost free. Weather variables affect the crop growth differently in different phenophases during its growth cycle. Field experiments during the rabi seasons of 1989-90 and 1990-91 were conducted with cv Ganga Safed-2 and were laid out in split plot design with three dates of sowing as main plot and four irrigation regimes as sub-plot, replicated six times. The results obtained in the study revealed that, the lower temperatures observed in silk emergence to physiological maturity phase gave higher grain yields. The crop had the maturity periods ranging from 104 to 112 and 121 to 131 days from emergence in 1989-90 and 1990-91, respectively. Higher crop growth rate coupled with lower leaf weight ratio contributed towards higher grain yield. The peak leaf area index beyond certain threshold value did not contribute to higher grain yields. Radiation use studies indicated higher intercepted solar radiation and intercepted photosynthetic active radiation use efficiencies for first date of sowing (October 5) in both the years of study; the higher values being noticed in 1990-91. The extinction coefficient (K) calculated by using incident solar radiation and transmitted solar radiation showed a value of 0.78. Grain yields were significantly higher in first date of sowing in the year 1990-91. This was because of lengthening in grain filling period due to lower temperatures. Irrigation scheduling technique by infrared thermometry could save 20-25% of irrigation water over farmers' method. Yield attributes such as test weight, ear weight and ear numbers positively contributed towards grain yields. Correlation studies between grain yield and weather parameters revealed that lower temperatures from tasseling and morning and afternoon vapour pressures throughout the growing season played a major role in deciding final grain yield. During silk emergence to physiological maturity both solar radiation (SR) and photosynthetic active radiation (PAR) showed significant positive correlation with grain yield indicating better source and sink relationship. Agrometeorological indices like accumulated growing degree days (GDD),helio-thermal units (HTU) and thermal interception rate (TIR) had significant positive correlation with grain yield during silk emergence to physiological maturity. Stepwise regression analysis selected afternoon vapour pressure and mean temperature during silk emergence to dough stage for predicting the grain yield SO-30 days before maturity. For even early prediction, accumulated PAR in emergence to tassel emergence stage was selected with lower p R value (0.73), which predict the grain yield 50-60 days before maturity. Path analysis of grain . yield and weather parameters observed in important phenophases indicated that, low maximum temperature in tassel emergence to dough stage and higher SR in silk emergence to physiological maturity are favourable for higher grain yields. Prediction models were also developed by using stepwise regression technique for predicting stover yield and total biomass yields. The models include accumulated HTU in tassel emergence to silk emergence for stover yield prediction and temperature range in emergence to silk emergence for predicting total biomass respectively. The models obtained could predict 40-50 days before maturity. CERES-maize model was corrected for genetic coefficients and was found to be' good for prediction for this region. CERES-maize model could predict the silking and maturity date with minimum error. However, the grain yields predicted by CERES-maize model showed larger error compared to that of yields predicted by regression models obtained in the study. In addition to the larger error, the CERES-maize model has the limitation of predicting the yield at the end of growing season. However, prediction models obtained in the study could predict the grain yield, stover yield and biomass production well in advance.