Crop water requirements of crops in Appapuram Channel Command under Krishna Western Delta were computed with CROPWAT using the meteorological parameters. The major cultivated crops are rice and maize. The total water requirement for these crops has been computed. The CROPWAT a computer simulation model was used to estimate crop water requirement in Appapuram Channel Command under Krishna Western Delta in Andhra Pradesh for the years 2000 to 2010. The Penman – Monteith method was used for evapotranspiration calculation in the model. It was estimated that the gross water requirement for Appapuram Channel Command area to irrigate 8880 ha was registered and 4000 ha unregistered ayacut during kharif season and maize 4000 ha during Rabi to be 124.39 M.cum. The canal operation plan was prepared for estimated gross water requirement.

The study area is situated in the North-Eastern dry zone of Karnataka at 16º 17´ N latitude and 77º 9´ E longitudes to 16º 23´ N latitude and 77º 18´ E longitudes. The drainage network of watershed was delineated and parameters required for morphometric analysis is computed using ESRI Software ArcGIS 10. The drainage pattern of the study area is dendritic with stream order 5. The bifurcation ratio reflecting geological and tectonic characteristics of the watershed was estimated at 4.36 indicated that the watershed has suffered less structural disturbance. The drainage density of watershed is 5.89 km/km2 indicate the closeness of spacing of channels, thus providing a quantitative measure of the average length of stream channel for the whole watershed. The values of form factor and circulatory ratio of watershed indicate that the watershed is approaching towards the elongated shape. Hence, it is concluded that GIS techniques proved to be a competent tool in morphometric analysis.

Land development is one of the prime components of precision farming. Unevenness of agricultural fields leads to the in-efficient use of irrigation water, which in turn reduces the yield and farm income. Levelling index, which is a dynamic factor, determines the quality and accuracy of land levelling. Therefore, it is imperative to study the temporal variability of levelling indices. A field experiment was conducted at two different duration viz., 2009-2010 and 2012-2013 in the research farms of UAS, Raichur, Karnataka state. The study was taken up during the year 2009-10 as first observation to find levelling index of the fields by different methods viz., the conventional levelling and the tractor operated laser guided land leveller. A comparative evaluation of the laser guided land leveller with the conventional system of levelling revealed that, the percentage reduction in standard deviation of reduced levels at grid points of 10X10 m with-in the field for before and after levelling was 85.7 % for laser levelling, and that of 46.79 % for the conventional method which was 38.91 % lower when compared with the laser levelling. The levelling indices before and after conventional levelling were 0.18 m and 0.10 m and the same for before and after laser levelling were 0.17 m and 0.02 m respectively. During the year 2012-13, the levelling indices of the fields levelled by conventional and laser levelling methods were 0.20 m and 0.07 m respectively. The standard deviation of reduced levels for fields levelled by conventional and laser levelling methods were 0.25 m and 0.08 m respectively. Though the temporal variability with respect to levelling indices was observed in both conventional and laser levelled fields, the lesser variations were found in laser levelled field.

The study is carried out to examine the climate variability and its impacts on agricultural water resources to achieve the stable and sustainable crop-water management and minimize its effects. Monthly district-wise SPI analysis revealed that both increase and decline in precipitation amount as well as there is a varying tendency in the number of dry and wet years observed in the study area in the last twelve years (2001-2012). Analysis of water requirement of different crops at zonal-wise showed that there is significant of impact of climate variability in the study area and it is heterogeneous in nature. In the Northern dry zone irrigation requirement (IR) is increased by 107.9, 33.1 and 314.4% for the cotton, ground nut and maize crops respectively. The climate variability has positive effect in terms of IR on four zones of study area such as Eastern dry zone, North eastern transition zone, Central dry zone and North eastern dry zone.

The study has been conducted to investigate the engineering properties of popular varieties of maize grown in Karnataka viz.; Mahyco [Hero 550], Hema variety, Ganga Kaveri [GK 3090] and CP 818 were selected in Karnataka. The engineering properties such as mean linear dimensions such as length, width and thickness of maize grain were found as 10.99 mm, 8.18 mm and 5.15 mm, respectively. The mean length, diameter and weight of un-dehusked cob were 179.36 mm, 53.88 mm and 212.76 g, respectively, with a Standard Deviation [SD] of 29.56 mm, 4.37 mm and 13.56 mm, respectively. The Physical properties viz., roundness, arithmetic mean diameter, geometric mean diameter, sphericity, surface area, bulk density, true density, bulk density, true density, moisture content, test weight of grains [W1000] and grain to straw [husk and grainfree cob] ratio were observed as 0.28, 8.15 mm, 7.69 mm, 0.69, 209.17 mm2, 0.74 g cc-1, 1.03 g cc-1, 276.58 g and 3.30, respectively. The aerodynamic property, i.e. terminal velocity of grain varied from 14.56 to 15.6 m s-1 with 0.43 m s-1 SD, whereas the mean terminal velocity of husk was 1.2 m s-1. The frictional properties such as angle of repose was found 22.76Ëš and coefficient of friction was 0.31 [grain-grain], 0.35 [grain-fly wood], 0.44 [grain-MS sheet] and 0.50 [grain to wood].