1Additional Director (Extension Education), Punjab Agricultural University, Ludhiana, Punjab 141 004
2Assistant Agronomist, Punjab Agricultural University, Ludhiana, Punjab 141 004
3Senior Scientist, ICAR-Indian Agricultural Research Institute, Pusa Campus, New Delhi 110 012
4Research Scholar, Punjab Agricultural University, Ludhiana, Punjab 141 004
Punjab Agricultural University, Ludhiana, Punjab 141 004
*Corresponding author's Email: buttargs@rediffmail.com
Online published on 9 October, 2017.
A field experiment was conducted during the winter (rabi) seasons of 2012–13 and 2013–14 at Ludhiana, Punjab, to study the spectral characteristics of Rumex spinosus L. in wheat (Triticum aestivum L.) and to identify the optimum time for distinguishing R. spinosus from wheat crop. The treatments consisted of different density levels of R. spinosus, viz. 5, 10, 15, 20, 25 and 30 plants/m2 and a sole population of R. spinosus and solid wheat stand. A decreasing trend in growth, yield-contributing characters and grain yield of wheat was observed with the increased population densities of R. spinosus from 5 to 30 plants/m2. The highest grain yield (5.4 t/ha) was recorded in sole wheat crop and a weed density 30 plants/m2 recorded the lowest grain yield (2.9 t/ha). The highest values of radiance ratio and normalized difference vegetation index (NDVI) were recorded in pure wheat crop and the least in sole R. spinosus. Solid stand of wheat crop can be distinguished from sole R. spinosus 30 days after sowing (DAS) and remain distinguished up to 120 DAS and but different density levels of R. spinosus can be discriminated amongst themselves from 60 DAS onwards.
Grain yield, Growth, Remote sensing, Rumex spinosus, Wheat
