Doubling farmers' income through Populus deltoides-based agroforestry systems in northwestern India: an economic analysis.

There is widespread use of poplar in pulp and paper, match splints, pencil and plywood industries, in northern India. The practice of closer spacing geometry with compact block in poplar cultivation does not permit intercropping from the third year onwards, which discourages small landholders. In 2008, poplar was planted at the Chaudhary Charan Singh Haryana Agricultural University, Hisar, India in three spacing geometries of 5 × 4 m, 10 × 2 m and 18 × 2 × 2 m (paired row) at a constant density of 500 trees ha-1. In the present study, two cropping rotations (sorghum-berseem and cowpea-wheat) were intercropped in all three spacing geometries of poplar (up to eight years of rotation), and compared with sole cropping as a control. The results showed that yield of annual crops reduced considerably over the years due to enhancing competition for light, moisture and nutrients. The overall yields of annual crops in various spacing geometries of poplar were reduced by 5.67% in the second year to 45.59% in eight years of plantation. The study resulted in 10 × 2 m spacing of poplar with sorghum-berseem crop rotation exhibiting the highest net returns (Rs 1,191,241 ha-1), NPV @ 12% discounting (Rs 409,673 ha-1), B : C ratio (1 : 2.22), IRR (70%), highest land equivalent ratio (2.28) and land expectation value (Rs 2,242,372 ha-1). In the study, LER and LEV calculated to increase the efficiency and adoptability of agroforestry systems. Therefore, on the basis of economics, the present study concludes that the intercropping of sorghum-berseem and cowpea-wheat in poplar planted at a spacing of 10 × 2 m is more profitable and helpful in doubling farmers' income over traditional agriculture in northwestern India. [ABSTRACT FROM AUTHOR]