Abstract:
Application of chemical fertilizers results in adverse effects on soil health, which could
be replenished by incorporation of organic amendments viz., green manure, green leaf
manure, farmyard manure, etc. The unavailability of good agronomic practices is the
main problem in cultivating green manure crops. In summer, many agricultural lands
are fallowed in the tropical region due to environmental constraints, and these can be
effectively utilized for the cultivation of green manure to produce quality seeds. In this
regard, a field experiment was conducted in Sunn Hemp during summer with different
sowing dates (D1 - January 4th week, D2 - February 1st week and D3 - February 2nd week)
and nutrient levels (N1 - 20:40:20 kg NPK ha-1, N2 - 25:50:25 kg NPK ha-1, N3 - 30:60:30
kg NPK ha-1 and N4 - 12.5 t FYM ha-1). Field investigation results revealed that all growth
characters were relatively higher in February second week sown Sunn Hemp with the
nutrient application of 30:60:30 kg NPK ha-1. However, yield attributes such as the
number of capsules per plant, number of seeds per capsule, seed index, pod weight per
plant, pod setting percentage, pod filling percentage, flower shedding percentage, seed
yield, stalk yield, and harvest index and economics were significantly (p<0.05) higher in
Sunn Hemp sown in the 4th week of January coupled with the nutrient application rate
of 30:60:30 kg NPK ha-1. The yield increase of 32.1 percent was associated with Sunn
Hemp sown in the 4th week of January over February 1st week. Hence, Sunn Hemp sown
in the 4th week of January with the nutrient application of 30:60:30 kg NPK ha-1 could be
highly beneficial to the farming community in the western agroclimatic zone of Tamil
Nadu.
