Chickpea (Cicer arietinum L.) is known to be sensitive to many herbicides and, therefore, choices for using post-emergence herbicides for weed control are limited. The present study was aimed at identifying sources of tolerance to two herbicides with different modes of action (imazethapyr—amino acid synthesis inhibitor; and metribuzin—photosynthesis inhibitor) for use in breeding herbicide tolerant cultivars. Screening of 300 diverse chickpea genotypes (278 accessions from the reference set and 22 breeding lines) revealed large genetic variations for tolerance to herbicides imazethapyr and metribuzin. In general, the sensitivity of the genotypes to metribuzin was higher compared to that for imazethapyr. Several genotypes tolerant to metribuzin (ICC 1205, ICC 1164, ICC 1161, ICC 8195, ICC 11498, ICC 9586, ICC 14402 ICC 283) and imazethapyr (ICC 3239, ICC 7867, ICC 1710, ICC 13441, ICC 13461, ICC 13357, ICC 7668, ICC 13187) were identified, based on average herbicide tolerance scores from two experimental locations each. The herbicide tolerant lines identified in this study will be useful resources for development of herbicide tolerant cultivars and for undertaking genetic and physiological studies on herbicide tolerance in chickpea.

A field experiment was conducted during the winter (rabi) season of 2021–22 at Indian Agricultural Research Institute, New Delhi, to investigate the effect of nano-urea and herbicides on yield and yield-attributing characters of wheat (Triticum aestivum L.). The experiment was tested in a split-plot design with 4-nano-urea based treatments, viz. control (no nitrogen), recommended dose of nitrogen (RDN) 120 kg N/ha, 50% RDN + 2 sprays of nano-urea, at 40 and 60 days after sowing (DAS) and 75% RDN + 1 spray of nano-urea (at 60 DAS) in main plots and 4 herbicides based weed management options, viz. sulfosulfuron 75% + metsulfuron methyl 5% WG (ready mix) @ 40 g a.i./ ha at 30 DAS; tank-mix of clodinafop propargyl and carfentrazone-ethyl (60 and 20 g a.i./ha) at 30 DAS; weed-free check and unweeded check, in subplots and replicated thrice. Results revealed that, yield attributes were significantly higher with 100% RDN. This treatment also resulted in 40 and 18% more grain yield with 100% RDN (5.21 t/ha) over 50% RDN + 2 sprays of nano-urea (3.7 t/ha) and 75% RDN + 1 spray of nano-urea (4.4 t/ha) respectively. Among the weed-management options, weed-free check was superior in yield and yield attributes followed by tank mixed carfentrazone ethyl + clodinafop propargyl (60 and 20g a.i./ha) at 30 DAS. However, tank mixed carfentrazone ethyl + clodinafop propargyl was significant superior to the ready-mixed metsulfuron methyl + sulfosulfuron in terms of number of ear-bearing tillers/m2 and number of grains/spike which resulted in significantly higher grain yield. Thus, 100% RDN (120 kg N/ha) along with tank-mixed carfentrazone ethyl + clodinafop propargyl (60 and 20 g a.i./ha) at 30 DAS are the more productive options for wheat-growing farmers keeping view of the uprising labour cost in manual weeding.