Indian Journal of Plant and Soil

The results of the experiment revealed that due to sulfur deficiency newly emerging younger leaves became yellow and chlorotic. As deficiency increases leaves became yellowish white and chlorosis was clear. The roots of the gerbera plant became small as compared to all nutrients treatment. Flower color changes from orange to light orange (from Indian orange to nasturtium orange) from 155 days onwards up to the last harvest.

An experiment was carried out at the ICAR-Central Soil Salinity Research Institute, Canning Town research farm to study the effect of different ameliorants on soil physicochemical properties and crop growth. The experiment was carried out in a split-plot design where the ameliorants were put in the main plot and their doses in the sub-plots. Soil samples were collected from 0-15 cm depth after two years of decomposition and were processed. Rice cv. Lalminikit (WGL- 20471) was grown in winter (2021-22) for studying the effect of salinity and ameliorants on its growth. Saturated moisture content, bulk density, saturated hydraulic conductivity, and organic carbon were also determined. Soil bulk density decreased with an increase in the number of doses, 1.20 Mgm-3 for 12 t/ha amendments. The value was 1.33 Mgm-3 for control. The saturated hydraulic conductivities were also dependent on the treatment and doses. The hydraulic conductivity values were a little higher for F.Y.M. and poultry manure treatment (5.0-5.2 cmh-1) than for green leaf manure and tank silt treatments (3.7-4.5 cmh-1) for the soil. Leaf area index and NDVI values were slightly higher in F.Y.M. and poultry manure treatments (3.5-3.6 and 0.42-0.45, respectively) which were higher than green leaf and tank silt treatments (3.2-3.3, 0.40-0.42, respectively). Similarly, rice grain and straw weights were higher for F.Y.M. and poultry manure treatments ((3.4, 4.5, and 3.5, 4.7 t/ha, respectively) than other treatments.

Uniform crop growth and subsequent higher production are possible if moisture is equally distributed, and timely, in the vicinity of the root zone. Several companies manufacture different components of drip and micro sprinkler systems. Farmers purchase those and install the system through technical experts or sometimes themselves. If the system is designed properly and installed correctly, then, the water application losses can be minimized following the time of operation of the systems. However, the variation in water application depth should not be more, less than 10-15% for micro irrigation systems. As such it is essential to verify the hydraulics, especially uniformity, of emitting devices and whether each plant receives the desired discharge/ depth of water. In view of this, different micro sprinklers were evaluated for uniformity by Wilcox Swailes uniformity coefficient and distribution uniformity at different micro sprinkler spacing and different operating pressures. The experiment was conducted on five different types of micro sprinklers (coded for identification as MS-1, MS-11, MS-111, MS-IV, and MS-V) at three operating pressures (1.0, 1.5, and 2.0 kg/cm2) and for micro sprinkler spacings of 3m × 3m, 4m × 4m, 5m × 5m. 6m × 6m, 7m × 7m, 8m × 8m, 9m × 9m and 10m × 10m. The depth distribution data obtained from the experiment were analyzed for Wilcox-Swailes uniformity coefficient (UCC) and Merriam and Keller Distribution Uniformity (DU). The decreased values of Uniformity coefficient and distribution uniformity were observed with an increase in the spacing of micro-sprinklers. At the rated pressure (2kg/cm2), the maximum value of UCC (93.85%) was recorded for MS-V at 3m x 3m micro sprinkler spacing with Wilcox-Swailes uniformity coefficient. The value of Hart uniformity confidence was also the highest (94.29%) at these pressure and spacing. The distribution uniformity recorded at these pressure and spacing for MS-V was 96.75%. More than desired value (70%) of the Wilcox-Swailes uniformity coefficient was recorded only for MS-I, MS-III, and MS-V for the spacings of 3m x 3m to 6m x 6m. For wider spacing (7m x 7m to 10m x 10m), the uniformity coefficients were less than 70% i.e. less than desired values. Considering the uniformity of Wilcox-Swailes and Merriam and Keller Criteria, MS-V showed superiority over all other micro-sprinklers.