Browsing by Author "Shekh, A. M."
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ThesisItem Open Access CROP-PEST-WEATHER INTERACTION AND POPULATION DYNAMICS OF (Heliothis armigera (Hubner) IN TWO DIVERSE PIGEONPEA (Cajanus cajan (L.) Millsp.) GENOTYPES (BDN-2 and GT-100) AT ANAND(AAU, Anand, 1998) Chaudhari, G. B.; Shekh, A. M.The results obtained in this investigation revealed that the air temperature and photoperiod had profound influence on growth and development of the pigeonpea crop. The variation in air temperatures during different phenophases resulted in differential attainment of physiological maturity in both the genotypes. Whereas, the differential availability of bright hours of sunshine (BSS) during reproductive phase resulted in higher seed yield. Low vapour pressure (VP) and relative humidity (RH) during flower bud initiation to podding phase, were favourable for higher seed yield. The seed yield and other yield attributing characters of pigeonpea crop were significantly influenced by the different treatments. The seed yield of protected condition was observed 36% higher than that under unprotected condition. The short duration genotype, GT-100 was found significantly higher in seedyield than the long duration genotype BbN-2. The seed yield was found to decrease upto 35%, with delayed sowing till 40 days after the onset of monsoon. Significant differences in total biomass were noticed in treatments like irrigation, genotypes and dates of sowing The results from correlation study revealed that there was a positive significant association between seed yield and different weather parameters like, maximum and minimum temperatures, bright hours of sunshine and different thermal indices like, growing degree days, phototherraal units and Heliothermal units and accumulated PAR. It has been observed that there was a difference in growing degree days requirement for the two genotypes to attain different phenological phases. To attain physiological maturity the GDD requirement for BDN-2 was 3105°Cd and it was 2894°Cd for GT-100 genotypeThesisItem Open Access ESTIMATING WHEAT YIELDS IN GUJARAT USING WTGROWS AND INFOCROP MODELS(AAU, Anand, 2003) AKULA, BABY; Shekh, A. M.Crop simulation models are valuable tools to researchers to help them to understand the influence of climatic variables on crop productivity. The model estimated yields are handy to the agencies in government, trade and industry for planning about distribution, storage, processing, export or import of crop produce. Yield estimates by the models are also useful in taking timely policy decisions on fixing levy prices, because the estimates of the yield are available well in advance of the actual harvesting of the crop. Hence, a two-pronged approach was followed to estimate wheat yields in Gujarat, with the help of WTGROWS and InfoCrop simulation models. Initially both the models were calibrated and validated under Anand conditions through field experiment laid out in a strip plot design with three replications during rabi season of the years 2000 and 2001. Tliree dates of sowing were assigned as a main plot treatment with four irrigation regimes as sub plot treatments. Consistently higher yields were realised in case of the second date of sowing (15* Nov) during both the years although the yield differences were not statistically significant. Relatively more yields were realised in 2000 than those realised in 2001 and this was due to prevalence of favourable low temperatures during 50-90 DAS - a period that corresponded with anthesis to dough stage in conjunction with intermittent cold spells from 70-75 DAS corresponding with soft dough phase in the former year. In contrast to what was observed in case of yields in relation to the dates of sowing, yield data due to different irrigation treatments showed significant differences among them. Three irrigations gave significantly the lowest yield as compared with yields realised through any other irrigation treatment. The lowest yields realised in the treatment involving three irrigations were due to prevalence of moisture stress during tillering and flowering. Paradoxically, six irrigations despite not missing any important physiological stage, did not record significantly higher yield in comparison with yield in response to five irrigations. This was on account of the fact that, luxurious vegetative growth in the former case had caused lodging, as the prevailing wind speed was high. Different test criteria were followed to validate the performance of the models. Besides, error per cent was also calculated in all the different treatments to express the deviation in simulated values from those observed. Close scatter of simulated yield and total dry matter and respective measured values around the regression line and 1:1 line in case of both the models indicated good agreement between them. Both the models exhibited their robustness in predicting yields by explaining more than 90 per cent of variation in yield and total dry matter on an overall basis. However, there still remains some scope for improvement of the models in accounting for the loss due to lodging. The estimated RMSE for yield by WTGROWS was 318 kg ha-1, while that for yield by InfoCrop was 360 kg ha-1. Among the different dates of sowing, error per cent was relatively low in the treatments of the second date of sowing when compared with that for other dates. Both the models displayed decrease in error per cent with increase in irrigation levels. Underestimation of the simulated yield was more when the number of irrigations was less [three (I1) and four (I2)] when compared with that for more irrigations [five (I3) and six (I4)]. The underestimation was relatively more in case of InfoCrop, than that in case of WTGROWS. The performance of the models could be adjudged with the index of agreement (D), which was relatively high for WTGROWS (D= 0.97) than that for InfoCrop (D=0.95) in terms of yield. The models were also observed to perform in a similar way in terms of their response to the treatments in case of total dry matter, phenology and LAI also. The days to anthesis and maturity were simulated with less accuracy by both the models as compared to that of yield. Anthesis by WTGROWS explained more variance (R2=0.82) than that explained by InfoCrop (R2=0.75). The performance of these models in explaining the variance due to days to maturity was reverse of what was observed in case of anthesis. The highest and the .lowest ET were observed in case of the treatments of D2I4 and Dili, respectively. WTGROWS also showed similar pattern. Relatively higher proportion of MBE as compared to that of MAE during both the years in terms of ET as simulated by WTGROWS revealed under- prediction of ET by the model. Nonetheless, the error per cent did not cross the limit of -15 per cent during both the seasons except in case of Dill (-15.77%). Both the models expressed sensitivity to weather parameters viz., temperature, radiation and CO2 levels under both potential and stressed test conditions. But, the magnitude of change from the respective base yields in case of both the models was more to temperature under stressed conditions. However, the magnitude of response was more in case of WTGROWS than that in case of InfoCrop on overall basis except in case of radiation under stressed conditions where InfoCrop exhibited relatively more sensitivity. Linear response to TTVG, POTGWT, GNODMA, NSOILI, WLSTI was observed in case of both the models. The sensitivity was relatively more in case of WTGROWS than in case of InfoCrop. Moreover, InfoCrop exhibited linear response to RGRPOT and SLAVAR also. Statistical analysis of the historical actual wheat yield data of the state revealed that the average actual yield for the state as a whole was 2.5 t ha-1. Out of the ten districts selected to understand the temporal and spatial variability in wheat production levels and further to estimate yield gap through linking the model results with GIS, only Junagadh, Banaskantha and Bhavnagar exhibited significant positive linear trend at an average increase rate of 66, 31 and 25 kg ha-1 yr-1, respectively. Majority of the other districts failed to exhibit any discernible linear trend. However, Mehsana was found to be the second potential wheat producer of the state after Junagadh. The estimated average district potential yield by the models was 5.9 t ha-1 on overall bases. This is 2.36 times higher than the average actual state yield and is due to favourable thermal regimes as it was evident under Anand conditions where the estimated TTVG explained 87 per cent of variation in the potential yield and indicated significant linear positive trend. Similar reasoning holds good for higher potential yields in other districts. The attainable yields were estimated by imposing the management constraint of delayed sowing by twenty days from the optimum time (15thNov). The attainable wheat yields were found to decrease in all the districts irrespective of the agro climatic zone. The estimated attainable yield for the state as whole was 4.8 t ha-1 on the basis of the ten districts considered in the study. The average sowing yield gap between potential and attainable yield varied from 863 to 1205 kg ha-1 Reduction in yield due to delayed sowing was highest in the districts of Saurashtra which was followed in this respect by middle Gujarat, north Gujarat and south Saurashtra in sequence. The quantity of reduction in succession in these agro climatic zones was to the tune of 60, 59, 49 and 44 kg ha-1 per day delay in sowing, respectively.ThesisItem Open Access POTATO CROP GROWTH AND YIELD PREDICTION USING SPECTRAL INDICES AND METEOROLOGICAL PARAMETERS(AAU, Anand, 2000) RAO, GATTINENI SRINIVASA; Shekh, A. M.Potato {Solarium tuberosum L.) is one of the four major crops of the World after rice, wheat and maize. It is one of the World's most nutritious plant sources of food for human consumption. Potato can be raised in wide range of climatic conditions. Plant growth and tuber production are markedly influenced by environmental conditions particularly temperature and radiation. Response of a plant to radiation in different spectra indicates the status of plant stand. This information can be explored for advance estimation of crop yield through satellite imagery. However, before it could made available, one has to identify the significant spectral bands contributing to the yield. Advanced estimation of crop production for the major food crops is considered essential for taking judicious decisions on procurement, storage, pricing and marketing of these commodities, and also for strengthening the public distribution system. The development of crop yield prediction models is necessary for assessing the production of a particular crop in a region. An experiment on potato crop was conducted with the objectives to develop the models, which would predict the final tuber yield using spectral indices and meteorological parameters, to study the variation of spectral characteristics with the change of growth parameters, to develop the interrelationships among growth parameters and vegetation indices, to develop the model that could predict different growth parameters using spectral indices and meteorological parameters and to study the crop weather interrelationships between the potato growth at various phases of development and the meteorological factors. The field experiments were conducted on potato cv. Kufri Badshah, JL-4780; during the rabi seasons of 1996-97 and 1997-98 in split plot design with three dates of sowing (viz., D1: 25th October, D2: 15th November and D3: 6th December) as main plots and two irrigation regimes (viz., I1: farmers' method of irrigation and I2: GAU recommended method of irrigation) as sub-plots, replicated six times. The results obtained in the present investigation revealed that the planting date had a significant effect on attainment of different phenophases, crop growth and tuber yields. But the irrigation regimes adopted for the present study had non-significant effect on the final tuber yield. The crop sown during the 3rd week of November recorded significantly higher yields (i.e., 34.95 t ha-1) than that grown either earlier (i.e., October, 20.03 t ha-1) or later (i.e., December, 31.84 t ha-1). It was observed that there was a progressive delay in the number of days to attain 50% emergence with early planting due to higher temperatures, i.e., > 22 °C. The analysis of meteorological parameters vs. phenological phases and yield revealed that the optimum mean air temperature for 50 % emergence was 21.5 °C. While, the optimum soil temperature at 5 cm depth for the same phase was 24.4 °C. The optimum mean air temperature and soil temperature at 5 cm depth for tuber initiation were respectively 19.9 °C and 22 °C. For tuber development, bulking and physiological maturity, the mean air temperatures were respectively 20.6, 18.3 and 18.9 °C. The optimum soil temperatures at 5 cm depth for the same phases were 22.3, 20 and 21.2 °C, respectively. The Huctuations in bright sunshine hours in the November date of sowing were less than those for the other two date of sowing,, during both the years. This contributed to the higher final tuber yields in the November sown crop. In general, the optimum range of different meteorological parameters for higher yields were 18 to 22 °C, 20 to 24.4 °C and 7.9 to 9.9 h for mean air temperature, soil temperature at 5 cm depth and bright hours of sunshine, respectively. The results of the correlation studies conducted between days taken to complete different phenophases and accumulated growing degree days (AGDD) showed a very strong positive significant relationship (r = 0.98) between them and the regression model developed to predict the attainment of different phenophases performed fairly accurately (R2 = 0.97). The crop sown on 15th November, recorded higher leaf area index (i.e., LAI = 5.19) and the corresponding crop growth rate was 24.9 g m-2day-1, which contributed to the achievement of higher tuber yields of 38.12 t ha-1 The model developed for prediction of maximum LAI using AGDD, predicted LAI with the coefficient of determination of 0.80. The average absorbed photosynthetically active radiation (APAR) use efficiency obtained for the present investigation was 2.39 g MJ-1, while its range was from 1.84 to 3.45 g MJ-1. The range of extinction coefficient (k) values obtained was 0.63 to 0.81 with an average value of 0.73. The correlation studies between APAR use efficiency and meteorological parameters revealed that the parameters maximum, minimum, mean temperatures and soil temperature at 5 cm depth had a significant negative interaction with RUE. The spectral indices viz., ratio vegetation index (RVI) and normalized difference vegetation index (NDVI), increased with crop growth irrespective of the treatment and was highest at maximum LAI. The highest values of RVI (i.e., 8.17) and NDVI (i.e., 0.82) were observed, in case of D2 sown crop. The results revealed that the saturation of spectral indices occurred at LAI values between 4.5 and 5. The regression models developed to predict the LAI using spectral data revealed that the NDVI model predicted with better accuracy (R2 = 0.94) compared with the prediction by RVI model (R2 = 0.88). But, for the prediction of dry matter accumulation both the RVI (R2 = 0.99) as well as NDVI (R2 = 0.96) models predicted the dry matter with better accuracy. The regression models developed for dry matter prediction using evapotranspiration (ET) and spectral indices, predicted the dry matter accumulation with the coefficient of determination of 98 and 97 % by using RVI and NDVI data, respectively. The regression models developed to predict LAI using APAR and spectral indices, predicted the LAI with the coefficient of determination of, respectively 93 and 94 % using RVI and NDVI data. The correlation studies conducted between spectral indices and tuber yield, APAR and dry matter revealed that there did exist a positive association between them. The regression models developed to predict the tuber yield on the basis of spectral indices and LAI as the independent variable, predicted tuber yield with the coefficients of determination of 53 and 59 % by inclusion RVI and NDVI data, respectively. The predictions held good, by using LAI and spectral data, at 70, 85 and 95 days after sowing. As against this, the regression models developed to predict tuber yield by using APAR and dry matter as independent variables along with spectral indices predicted the tuber yield with the coefficient of determination of 67 and 78 % by using RVI and NDVI data, respectively. In this regard, the best predictions could be obtained by using APAR, dry matter and RVI data at 35, 55 and 65 days after sowing and by using the data of APAR, dry matter and NDVI at 35 and 70 days after sowing.ThesisItem Open Access RADIATION REGIME OVER ROW ORIENTATION IN WINTER WHEAT (Triticum aestivum L.)(AAU, Anand, 2004) LUNAGARIYA, MANOJKUMAR MAVJIBHAI; Shekh, A. M.A field experiment was conducted during the rabi season of 2003-2004 at Anand. The experiment was laid out in Split Plot Design with the two dates of sowing as main plot and four treatment combinations of two row orientation and two row spacing as sub-plots, replicated four times. The objective was to study solar radiation regime with respect to the row orientation, row spacing and leaf geometrical parameters for Wheat crop (cv. GW- 496). The experiment was planned with the objectives to determine the influence of the treatments on the RUE, Extinction Coefficient (k), Direct beam radiation interception, soil surface temperature and soil moisture lost/evapotranspiration (as influenced by radiation penetration between rows). Comparison of the season encountered by the crop during the experimental period with that normally found in the region was made by comparing the seasonal values of different weather parameters with their normal for Anand. The nonsignificant differences in respect of each of the weather parameters established that the experimental season was identical to the normal one. Hence these results could be applicable to any normal wheat growing season around Anand region. The experimental findings obtained during the course of the present investigation revealed that the highest interception was recorded during the morning hours and there was negligible difference among the treatments in this respect. The difference in the interception was higher during noon time and narrow NS rows intercepted higher PAR (0.92). Wide NS rows and wide EW rows had higher solar radiation interception than that narrow EW rows at noon hours. The seasonal average of the fraction F indicated more or less identical results that representing different treatments, narrow NS oriented row had highest F value i.e.0.86 and while in narrow EW rows had the poorest value (0.77). There was low RUE in early growth stages because more solar energy was used up being incident on the soil surface rather than on the plants due to inadequate development of plant canopy. The RUE showed maximum value at booting stage. There was no significant difference in the RUE among the treatments and also among interactions. The difference in the RUE was found negligible. Slightly high RUE was found in the widely spaced EW rows during in second sowing (i.e.2.07 g MJm-2) as compared to the general mean (i.e.2.01 g MJm-2). The lowest RUE was observed in wider NW rows (i.e. 1.96 g MJm-2 and 1.97 g MJm-2 for respective sowing times). There was no statistically significant difference among HI values corresponding to different treatments revealed that there was no difference in fraction of radiant energy used for grain biomass. High averaged LAI was recorded in narrow NS rows during both sowing dates (3.26 and 3.7, in respective sowing dates). Wide NS rows (2.67 and 3.38, in respective sowing dates) succeeded this treatment. The EW rows produced lower LAI. The NS rows (narrow and wide) did not show much fluctuation in the values of k (extinction coefficient), while EW rows (narrow and wide) showed comparatively more fluctuations, indicating the changes in canopy structure. The average value of leaf orientation over the entire study indicated that leaves usually preferred N (16.6 %), S (16.1%) and W (13.2%) direction. General results showed the leaves were randomly oriented with different times. The seasonal average of direct beam interception fraction (I/I0) indicated that the in general, highest direct beam interception occurred on the first leaf and lowest on the second leaf while third leaf had intermediate direct beam interception. Maximum average interception fraction was 0.63 over the third leaf and minimum (0.22) over second leaf of the wider NS rows during second sowing. While, in case of the narrow NS rows of the first sowing, second leaf had high interception with 0.61 fraction, first leaf had value 0.24 and third leaf had fraction 0.41. Except these two. values for NS oriented treatments the leaves of the other treatments showed intermediate direct beam interception fraction ranging from 0.31 to 0.51 over the entire season. Soil surface temperature was observed to be slightly high at morning hours (1000 h) in the wider EW rows during both the sowings. Those for narrow EW rows followed these values. During noon time (1300 h), wide NS rows had higher soil surface temperature than respectively that for other treatments. In afternoon, the soil surface temperature did not show much difference among treatments. The difference in the temperature was considered as the function of the radiation penetration in the rows. Wide NS rows had higher evapotranspiration, in general after early growth period. Other treatments showed no distinct pattern in this respect. The moisture loss pattern had almost parallel trends for narrow and wide rows in particular orientation. This indicated that there was influence of spacing on evapotranspiration. The results revealed that NS rows and wider spacing had high radiation penetration.ThesisItem Open Access SIMULATION MODELING OF WHEAT YIELD USING WOFOST MODEL UNDER MIDDLE GUJARAT AGRO CLIMATIC REGION(AAU, Anand, 2013) MISHRA, SUDHIR KUMAR; Shekh, A. M.Crop growth simulation models are useful tools for considering and exploring the complex interactions between a range of factors that affecting crop performance, including weather, soil properties and management. To sustain crop production and to reduce the detrimental effects of varied environmental conditions on crop production, the understanding of crop growth in relation to varying resource input and agro-environments is required for management options. Improved production technology at the farm level is the most crucial starting point for future improvement of productivity of wheat by employing and adapting suitable crop growth simulation models. In addition to this, the use of crop growth simulation models comes handy to the government agencies, trade and industry and for planning about the distribution, storage, processing, and export/import of crop produce besides taking timely policy decisions on fixing levy prices as they provide accurate advance estimation of yields. Crop simulation models are recent tools that have facilitated identification of production constraints and for assisting in agro-technology transfer. In the present investigation, WOFOST (WOrld FOod STudy) v.7.1 model was used to develop genetic coefficients and validate it under Anand conditions by conducting a field experiment on Sandy loam soil during two consecutive Rabi seasons of 2009- 2010 and 2010-2011. The study was carried out for simulation of phenology. growth and yield of four different wheat cultivars (cv. GW 322, GW 496, GW 366 and GW 1139), vahdation of four dates of sowing viz., D1 (1st November), D2 (15th November), D3 30th November and D4 (15th December), cahbration of genetic coefficients of all four different cultivars, carry out the sensitivity analysis of WOFOST model with respect to middle Gujarat agro-climatic region. The cultivar GW 322 performed best during 2009-2010, 2010-2011 and in pooled analysis in producing the grain yield by 3611 kg/ha, 4384 kg/ha and 3998 kg/ha. Among all cultivars, GW 322 performed best (3611 kg/ha in 2009-2010 and 4384 kg/ha in 2010-2011) followed by cultivar GW 496, GW 366 and GW 1139. Although the durum type wheat cultivar GW 1139 yielded least among all cultivars. The yield reduction is more under delayed sowing. Although this cultivar (GW 1139) is cultivated under rainfed conditions in Bhal zone but, under irrigated conditions in Anand its performance was better in terms of duration as well as in yield. The mean maximum temperature of wheat growing season during first year ranged between 30.4 to 31.4 °C while, during second year it was between 28.9 to 31.3 °C under different dates of sowing. Higher maximum temperature caused the reduction in wheat yield. With an increase of 1°C in maximum temperature the wheat yield reduced by 412 kg/ha. Among different stages, the flowering stage was most vulnerable with increase temperature. At this stage, every 1°C increase in the maximum, minimum and mean temperatures respective reduction in yield was 213 kg/ha, 177 kg/ha and 231 kg/ha. Minimum temperature less than 11.5 °C at flowering stage was found more favourable for wheat production. This lower minimum temperature corresponds with the wheat sown on the normal dates (15th November) hence, it is recommended. The association between simulated and observed grain yields of GW 496, GW 366 and GW 1139 cultivars were found satisfactory. Consistently higher grain yields were realized in case of the second date of sowing (15th November) during both the years and the yields were statistically significant for the pooled data over the years. Average minimum temperature in D2 sowing around 11.5°C around 70 DAS and 8.4°C at 60 DAS in 2009-2010 and 2010-2011, respectively seemed to have contributed to yields under D2 being higher than those under D1, D3 and D4. The average minimum temperature in D2 sowing was found the lowest and prevalence of lower mean temperature during flowering and milking stage during both the years were found favourable for higher grain yield. The WOFOST model was superior to InfoCrop and DSSAT crop simulation models in simulation of days to anthesis and maturity of wheat crop. Various test criteria were applied to validate the performance of the model. The simulation performance of grain yield was found better in 2009- 2010 than in 2010-2011. The calibrated WOFOST model performed well for simulating phenological stages (viz., anthesis and physiological maturity) with error percent less than 4.03%. Similarly, the error percent was less than 8.48 for simulation of grain and biomass production. Hence, this model can be used for simulating the phenology and yield of wheat cultivars. Highest error 9.34% was noticed in simulation of leaf area index by InfoCrop and 9.21% by DSSAT model. The comparison of WOFOST with DSSAT and InfoCrop models suggested the superiority of WOFOST over others as it was evident from least percent error in simulating phenology, yield and yield attributes of wheat. The DSSAT models also simulated the phenology, yield and yield attributes of wheat close to the observed. This model estimated the yield, biomass and harvest index with percent error less than 7.83, -5.5 and 11.47, respectively. Index of agreement from all three models was more than 0.95 in simulations of various growth and yield components of wheat cultivars under varied environmental conditions reveal the accuracy of models.ThesisItem Open Access SOLAR RADIATION, PHOTOSYNTHETICALLY ACTIVE RADIATION AND THERMAL TIME RELATIONSHIP WITH CROP GROWTH IN SUMMER GROUNDNUT (Arachis hypogaea L.)(AAU, Anand, 1989) GAJJAR, R. B.; Shekh, A. M.A field experiment with two dates of sowing (D1-2nd January and D2 - 5th February), two varieties (V1- Robut 3 and V2- GAUG-2) and three irrigation levels (I1- irrigatic at 10 days interval, I2-irrigation at 15 days interval a I3-when Tc-Ta = ± 0.5°C) was conducted during the summer season of the year 1989 with objectives of (i) determining the relationship between solar radiation, PAR, LAI, DM and days after sowing in groundnut crop, (ii) relating the PAR attenuation to dry matter production and (iii) studying tin phenological behaviour and thermal requirement of groundnu cultivars with two dates of sowing. The study revealed that pod yields and fodder yield were at par with plots irrigated at 10 days interval and when Tc-Ta = ± 0.5°C. Both the cultivars yielded higher po yield when planted on 5th February. However, cv. Robut 33- had higher pod yield than GAUG-2.LAI and DM increased wit days after sowing at a linear rate^ The mean air temperature of 25.5°C during the flowering initiation in both the cultivars during both the plantings seems to have favoured higher pod and fodder yleids. Flowering began from 4 to 5 weeks after planting. Nine to ten hours of photoperiod at the time of peg Initiation was observed for both planting dates of cultlvars.ThesisItem Open Access STUDY ON PAR INTERCEPTION AND TESTING OF PLANTGRO MODEL FOR MUSTARD (BRASSICA JUNCEA L.) CROP(AAU, Anand, 1994) Patel, P. B.; Shekh, A. M.Mustard (Brassica juncea L.) is an important oil seed crop in India. Water is most often the limiting factor for mustard production and its optimum use is essential for higher yields. Evapotranspiration is an integral part of the overall water requirement' problem of any crop and its determination becomes both desirable and inevitable for better acquisition of the knowledge of water utilization by the crop. A field experiment with four depths of irrigation (T1-irrigation with 30 mm of water, Ig-irrigation with 45 mm of water, I o-irr igat ion with 60 mm of water and I4- irrigation with 75 mm of water) with four irrigations using sprinkler system each at a fixed interval was laid out in completely randomized block design during the rabi season of the year 1992-93. The results revealed that, the yield differences due to irrigation treatments were found to be non-significant. The data indicated that none of the irrigation treatments had any significant effect on the yield and yield attributing characters. The leaf area index (LAI) value was not sensitive to the different depths of moisture levels. Regression analysis between LAI and days after sowing (DAS) indicated that quadratic regression equation could fit well to predict LAI from DAS. Study on evapotranspiration indicated that total ovapotranspiration increased with increase in amount of water applied. Accumulated Stress Degree Days (SDD) values decreased with increase in amount of water applied. Correlation studies between dry matter production and intercepted photosynthetically active radiation (IPAR) indicated high positive correlations. Studies on intercepted photosynthetically active radiation (IPAR) indicated that IPAR use efficiencies ranged from 2.44 g MJ-1 in I2 treatment to 2.55 g MJ-1 in I1 treatment. The extinction co-efficient (K) calculated by using incident photosynthetically active radiation (PAR) and transmitted PAR showed a value of 0.87.