Did his B.Sc. (1973) Panjab University, M.Sc. (1975) Meerut University, Ph.D. (1978) GNDU, UNESCO-WHO Long-term course (1978-79) in Modern Problems in Biology from Institute of Experimental Botany (Praha, Czech rep). After a short period as CSIR Pool Officer in NEHU Shillong followed by PAU, Ludhiana, he joined as Lecturer in Plant Biochemistry in 1980 in Panjab University, Chandigarh. After joining as Lecturer, did Certificate course in German Language (1984) from Panjab University; followed by Certificate (1985), diploma (1986) and Advanced Diploma (1987) Courses in Evaluation, Methodology & Examination from Association of Indian Universities. To cater to the needs of the department started teaching Ecology and thus developed research interest in the field. Through open selections selected as Reader (1989) and later Professor (1997) in Botany. Served as Coordinator Centre of Environment (2001-2009) and Chairman Botany (2008-2011) and currently serving as Dean Research, Panjab University. Achieved highest Global Accreditation as Certified Sr Ecologist by Board of Professional Certification, ESA, USA (2005-15)
Academic and Research Achievements: Utilizing his academic background of Plant Physiology & Biochemistry, through field & lab experiments, he understood the ecological implications of exotic introduced trees like Eucalyptus and Poplar and invasive alien weeds like Parthenium, Ageratum, and Lantana in India. Deciphered reasons of lack of floor vegetation in Eucalypt plantations and busted the myth of drying up of its soil by documenting the release of toxins from the tree into the environment/soil (Allelopathy). He documented similar property in Invasive alien weeds also. He exploited this property of Eucalyptus and exotic invasive weeds as (a) novel weapon against noxious weeds, and (b) as growth regulator in low dose. He further pioneered the use of essential oils from aromatic plants against weeds. His work opened a new frontier of research for sustainable weed management using minimal amounts of eco-friendly, effective and economically better options. Deciphered the mode of action of pure natural compounds of herbicidal interest like parthenin, α-pinene, BOA (2-benzoxazolinone) and L-DOPA (L–3, 4-dihydroxyphenylalanine). He established that allelochemicals act through a multitude of metabolic pathways including photosynthesis, respiration and membrane integrity and cause oxidative burst and alter the scavenging mechanism in plant systems. His work has also provided ample evidence in support of ecological suitability and economic profitability of mix-culture of native and exotic species over monoculture of fast growing indigenous trees. He has also provided practical solution of converting the non-degradable mammal hair and birds feather into rich manure through vermitechnology. Likewise, added value to noxious weed Congress-grass (Pathenium hysterophorus) by converting it into nitrogen-rich manure and degrading Parthenin
Other Contributions: He is providing leadership to IUFRO Working Party 8.02.04 onEcology of Alien Invasive Species since 2006 and 4.02.02 on Multipurpose Inventories since 2000. Chairman, Expert Appraisal Committee of Govt. of India for Environmental Clearance of developmental projects of Chandigarh;Was Member of Senate (2004-2008) and Syndicate (2004-05) Panjab University; Published over 138 SCI journal papers with citations over 1400, 69 conference proceedings book chapters and, 7 review articles and 19 popular articles; h-index of 22. Many of the papers are rated as top 20 best cited papers. Authored 2 text books and edited 5 books published by Taylor and Francis (USA): Plant invasion in Forests and Agroforestry, Haworth Press (USA): Ecological Approach to weed management and Allelopathy in Agroecosystem and CABI (UK): Plant Invasion in Indian subcontinent.
Honours and Awards: Best Scientist Award of Haryana (2008-09) carrying cash prize of Rs 1 lac, a citation and trophy from the Govt. of Haryana; An awardee of UGC honorarium of Rs 15000 pm for being Fellow of > 2 academies; Awarded SAARC Chair in Bangladesh (2007-08); Adjunct Professor, Chinese Academy of Sciences, China for 2 years (2007-2009); Punjab Rattan Award for Environment Science and Education (2007-08); Dr K.K. Nanda Memorial Oration Lecture Award at Dopoli, Maharashtra (2007); B.P. Pal National Environment Fellowship Award (2001-03)highest award of the Ministry of Environment & Forests for work on Biodiversity;State honour for Teaching and Research in Environment from UT Chandigarh Government (1998); Nanda Memorial National Young Scientist Gold Medal Award for Research in Forestry (1988); Felicitations at the International Conference on Environment and Biodiversityat Delhi University (2008); Second Best Research Paper in Hindi Award by CSIR(1998); First Friday Forum Award for creativity in Environment (2010)