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Sunflower is an important oilseed crop grown under rain-fed situation during winter/summer seasons in Northern Karnataka, India. Most of rain-fed areas have salinity problem resulting in poor yields of sunflower crop. An effort was made to screen available sunflower germplasm against graded salinity levels and relate their yield performance to various physiological parameters. Among the genotypes tested, PAC-36 recorded the highest seed yield (20.9 q/ ha) followed by KBSH-1 (19.65 q/ha), MSFH-17 (17.5 q/ha) and Morden (9.95 q/ha). Among the physiological parameters, leaf temperature increased with increasing salinity while osmotic potential, stomatal conductance and transpiration rate decreased with increase in soil salinity in all the sunflower genotypes tested. Dominance of one or more of the physiological attributes in promising germplasm indicated genetic variability in mechanisms of salt-tolerance in sunflower.

The effects of application of domestic sewage water for over four decades on physical, chemical and biological properties of soils were studied at three sites in Gabbur, Mavanur and Katnur villages near Hubli city in North Karnataka, India. Long-term use of sewage irrigation improved soil physical properties in terms of decrease in bulk density and dispersion index and increase in aggregate stability and water holding capacity compared to the unirrigated check. Despite long-term irrigation with sewage water with an EC of [1 dS m -1 , the EC of soils was low (0.20-0.45 dS m -1 ). An increase of one-and-half to two times in organic carbon content, available N, P, K and S, in the sewage irrigated soils was observed compared to soils not irrigated with sewage. However, the available Zn, Fe, Cu and B increased only slightly with the exception of Mn which increased substantially. In general there was a decreasing trend of organic carbon, available N, P, K and S with distance away from the stream course. Despite no heavy metals in sewage water, they were detected in soils but not in toxic levels. There were 94, 80 and 60 % more bacteria, fungi and actinomycetes, respectively, in sewage irrigated soils over the non-irrigated soils. Further, the coliform bacteria (E. coli) were observed in soil samples, suggesting fecal contamination.

Fruit samples collected from different part of northern Karnataka districts of Dharwad, Gadag and Haveri, when peak fruit harvesting stage were collected the samples, were processed and analysed for various nutrients and thus, the data bank was established. By using Diagnosis and Recommendation Integrated System (DRIS), nutrient expressions, which have shown higher variance and lower coefficient of variation, were selected as norms viz, N/P(4.98), N/K (0.73), N/Ca (1.17), N/Mg (4.65), S/N(0.10), N/Fe(0.02), N/Zn(0.08) etc. In addition, five nutrient ranges have been derived using mean and standard deviation as low, deficient, optimum, high and excess for each nutrient to serve as a guide for diagnostic purpose. The optimum N ranged from 2.30 to 2.84%, P from 0.48 to 0.56%, K from 3.16 to 3.44%, Ca from 2.08 to 2.74%, Mg from 0.60 to 0.88% and S from 0.24 to 0.27%. Among the micronutrients, the optimum Zn ranged from 28.71 to 29.78 ppm, Fe from 113.60 to 150.03 ppm for byadgi chilli crop.

A soil survey was carried out in different groundnut growing calcareous Vertisols of Dharwad district, Karnataka, India. One hundred surface composite soil samples were collected from five talukas (mandal) of Dharwad district and analyzed for soil chemical properties and nutrient status. The results showed that soil pH, electrical conductivity, organic carbon, free CaCO3 content ranged from 6.9-8.9, 0.15-1.79 dS m-1, 2.40-9.10 g kg-1, 5.8 -22.2 respectively across the regions. Available nitrogen, phosphorus (P2O5), potassium (K2O) and sulphur contents widely varied from 107-268, 18.5 - 56.0 and 386- 876, 14.8- 41.0 kg ha-1, respectively. On the basis of nutrient index values, groundnut growing calcareous soils of Dharwad were categorized as deficient in available nitrogen, medium in available phosphorus and high in available potassium. Most of the samples were deficient in available Fe and Zn whereas DTPA-extractable Cu and Mn were above the critical limits. A significant and positive correlation was found between organic carbon and available nitrogen (r=0.730**). However, a negative correlation was observed between Soil pH and micro nutrients while CaCO3 was negatively correlated with available iron (r=-0.31**).