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SummaryAn extensive survey was carried out to study the effect of irrigation water on soil sodification, in terms of soil sodium adsorption ratio (SAR) and residual sodium carbonate (RSC), in a typical black soil of Karnataka and it was carried out in Mudhol taluka of Bagalkot district. The soil SAR and RSC varied greatly up on different sources of irrigation water. The values of SAR ranged from 0.79 in borewell irrigated soils to 18.43 in lift irrigated soils. Most of the studied soils (131 samples) were found to be safe from sodicity hazard with < 10 SAR values. In terms of RSC of soils ranged from -23.20 meq/l in lift irrigated soils to +11.70 meq/l in dryland soils. Majority of the black soils of Mudhol taluka (70.6 %; 101 samples) were found safe with low RSC values (< 1.25 meq/l) while, 23.8 per cent of the samples recorded higher RSC of > 2.5 meq/l.

Tomato is an important commercial vegetable crop grown throughout the world, is also known to tolerate the calcareous soil conditions. But, phosphorus availability is a major constrain affecting its yield and productivity. Application of sulphur(S) is known to enhance its availability through biochemical reactions and desorption process. To ascertain the quantity of P and S required to enhance the productivity of tomato, a field experiment was conducted in calcareous clay loam soil with five levels of P 2 O 5 (312.5, 250, 187.5, 125 and 0 kg ha-1) and four levels of S, applied at the rate of 2.5, 1.5, 0.5 and 0 per cent (w/w) equivalent to active CaCO 3 in soil. Increased rate of P and S application enhanced tomato growth recording highest with P 312.5 + S 2.5 which was on par with P 250 +S 2.5. But, the highest fruit setting rate (69.37%) was obtained with P 250 +S 2.5 resulting in higher number of fruits per cluster (4.94), fruits per plant (41.17), fruit weight (77.60 g), fruit diameter (5.17cm). All these yield parameters were manifested into marketable tomato fruit yield recording maximum of 42.30 t ha-1 with P 250 +S 2.5. The study established that application of 250 kg ha-1 P +2.5% S found to be statistically optimum for tomato in terms of its yield (42.30 ton ha-1).

The present research was carried in a seven year old pomegranate orchard cultivating Bhagwa variety during hasta bahar season, 2015-16. The experiment consists of six treatments that included application of 100 per cent recommended dose of fertilizer without (T 1 ) or with bioinoculants (T 2 ), supplementation of 25 per cent (T 3 and T 4 ) and 50 per cent (T 5 and T 6 ) recommended dose of N through organics (neemcake + pongamiacake -1:1) without or with bio-inoculants. The field experiment was laid out in Randomized Block Design (RBD) and replicated four times. Pomegranate growth parameters did not record significant variation, however, the plant height and secondary branches were relatively more in bio-inoculants and organics supplemented treatments. Flowering patter was significantly influenced by organics and bio-inoculants application. Highest number of hermaphrodite flowers was observed in T 6 (139.0) and T 5 (122) as compared to T 1 (86). The number of fruits were also highest in T 6 (98.01) followed by T 5 (89.10) but, fruit weight (301.44g) and size (78.77 and 100.81 mm fruit diameter and length) was maximum in T 4 (292.2g, 77.19 and 102.55 mm fruit diameter and length). All the above yield parameters has resulted in highest fruit yield of 26.43 kg plant -1 and 19.56 t ha -1 in T 6 (50% RD N&P +Organics + Bio-inoculants) while, lowest yield was observed in T 1 (100% RDF) recording 17.06 kg plant -1 and 12.62 t ha -1 .

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