This study aimed at utilizing unmanned aerial vehicle in place of a conventional hand sprayer for the smart delivery of agricultural inputs especially crop nutrients. A field experiment was conducted in the farms of Agricultural Research Station, Bhavanisagar, Tamil Nadu Agricultural University. There were nine treatments which were replicated thrice in a randomized block design. The treatments include NPK 19:19:19 along with liquid micronutrient, humic acid, and TNAU Maize maxim at two intervals viz., 50% Tasselling, and Cob filling stage. These nutrients were applied as foliar spray through battery operated and fuel operated drones and were compared with knapsack hand sprayer. Biometric observations such as plant height, leaf area, dry matter accumulation and yield parameters such as cob yield and number of grains per cob were observed during the critical crop growth stages. Foliar application of nutrients through drones had a significant influence on the growth and yield of maize crop. TNAU Maize maxim applied using the fuel-operated drone with an atomizer nozzle (T7) @ 30 lit/ac spray fluid recorded the maximum biometric and yield attributes than other treatments. Improved biometric attributes like plant height of 261.2 cm and 270.32 cm, LAI of 4.14 and 5.15, and DMP of 12354 kg/ha and 18564 kg/ha at 60 DAS and 90 DAS, respectively was recorded with drone spray. It also resulted in a grain and stover yield of 7195 kg/ha and 10942 kg/ha, respectively than hand sprayer.

Coconut, an important perennial tree largely grown in Tamil Nadu to the extent of 4.61 lakh hectares. Inthis study, attempt has been made to create a spatial data base on spatial changes of coconut acreage inCoimbatore and Tiruppur districts of Tamil Nadu. The methodology involves digital classification of satelliteimage and identifying coconut plantations and creation of spatial database of coconut area in Coimbatoreand Tiruppur districts for the period 2019 and compare the same with 2013 data. Total area of coconutunder Coimbatore and Tiruppur was found to be 80,065 and 58,357 ha respectively. A comparison betweenarea obtained from this study and the area statistics released by Coconut Development Board data wasdone using paired t-test and the p-value was 0.005, which showed that there was no significant differencebetween the two data and the RMSE value was also found to be low, which indicated that this methodologycan be adopted for mapping the coconut area. Change detection analysis showed that the area decreased in Coimbatore to the tune of 5.4 per cent, whereas there was not much change in Tiruppur district and reduction in area was only 0.2 per cent. The accuracy was worked out by comparing the assessment based on the Remote sensing data and the government estimates which showed a difference of 9.54 per cent indicating the accuracy of 90.46 per cent.