title: Quantification of Climate Warming and Crop Management Impacts on Cotton Phenology.
abstract: Understanding the impact of the warming trend on phenological stages and phases of cotton (Gossypium hirsutumL.) in central and lower Punjab, Pakistan, may assist in optimizing crop management practices to enhance production. This study determined the influence of the thermal trend on cotton phenology from 1980-2015 in 15 selected locations. The results demonstrated that observed phenological stages including sowing (S), emergence (E), anthesis (A) and physiological maturity (M) occurred earlier by, on average, 5.35, 5.08, 2.87 and 1.12 days decade-1, respectively. Phenological phases, sowing anthesis (S-A), anthesis to maturity (A-M) and sowing to maturity (S-M) were reduced by, on average, 2.45, 1.76 and 4.23 days decade-1, respectively. Observed sowing, emergence, anthesis and maturity were negatively correlated with air temperature by, on average, -2.03, -1.93, -1.09 and -0.42 days °C-1, respectively. Observed sowing-anthesis, anthesis to maturity and sowing-maturity were also negatively correlated with temperature by, on average, -0.94, -0.67 and -1.61 days °C-1, respectively. Applying the cropping system model CSM-CROPGRO-Cotton model using a standard variety in all locations indicated that the model-predicted phenology accelerated more due to warming trends than field-observed phenology. However, 30.21% of the harmful influence of the thermal trend was compensated as a result of introducing new cotton cultivars with higher growing degree day (thermal time) requirements. Therefore, new cotton cultivars which have higher thermal times and are high temperature tolerant should be evolved.
authors.affiliation: Department of Agronomy, Bahauddin Zakariya University, Multan 60800, Pakistan. shakeelahmad@bzu.edu.pk.
authors.forename: Shakeel
authors.initials: S
authors.lastname: Ahmad
authors.affiliation: Department of Agronomy, Bahauddin Zakariya University, Multan 60800, Pakistan. qaisermultan@gmail.com.
authors.forename: Qaiser
authors.initials: Q
authors.lastname: Abbas
authors.affiliation: Department of Agronomy, Bahauddin Zakariya University, Multan 60800, Pakistan. maharabbastarar@gmail.com.
authors.forename: Ghulam
authors.initials: G
authors.lastname: Abbas
authors.affiliation: Department of Agronomy, Bahauddin Zakariya University, Multan 60800, Pakistan. zartashfatima15@yahoo.com.
authors.forename: Zartash
authors.initials: Z
authors.lastname: Fatima
authors.affiliation: Department of Agronomy, Bahauddin Zakariya University, Multan 60800, Pakistan. atiqjugg@gmai.com.
authors.lastname: Atique-Ur-Rehman
authors.affiliation: Department of Agronomy, Bahauddin Zakariya University, Multan 60800, Pakistan. sahrishnaz.agronomist@gmail.com.
authors.forename: Sahrish
authors.initials: S
authors.lastname: Naz
authors.affiliation: Department of Agronomy, Bahauddin Zakariya University, Multan 60800, Pakistan. haseebyounis99@gmail.com.
authors.forename: Haseeb
authors.initials: H
authors.lastname: Younis
authors.affiliation: Department of Agronomy, Bahauddin Zakariya University, Multan 60800, Pakistan. rana_g676@yahoo.com.
authors.forename: Rana Jahanzeb
authors.initials: RJ
authors.lastname: Khan
authors.affiliation: Department of Environmental Sciences, COMSATS Institute of Information Technology, Vehari 61100, Pakistan. wajidnasim@ciitvehari.edu.pk.
authors.forename: Wajid
authors.initials: W
authors.lastname: Nasim
authors.affiliation: Department of Agronomy, Muhammad Nawaz Shareef Agriculture University, Multan 60800, Pakistan. ranahabib11@gmail.com.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Habib Ur Rehman
authors.affiliation: US-Pakistan Center for Advanced Studies in Agriculture and Food Security (USPCAS-AFS), University of Agriculture, Faisalabad 38040, Pakistan. aachattha1@yahoo.com.
authors.forename: Ashfaq
authors.initials: A
authors.lastname: Ahmad
authors.affiliation: Pakistan Meteorological Department, Islamabad 44000, Pakistan. grmet@yahoo.com.
authors.forename: Ghulam
authors.initials: G
authors.lastname: Rasul
authors.affiliation: Department of Agriculture, District Chiniot 35400, Pakistan. muhammasazamkhan@yahoo.com.
authors.forename: Muhammad Azam
authors.initials: MA
authors.lastname: Khan
authors.affiliation: Department of Agronomy, Sher-e-Bangla Agricultural University, Dhaka 1207, Bangladesh. mhzsauag@yahoo.com.
authors.forename: Mirza
authors.initials: M
authors.lastname: Hasanuzzaman
keywords: CSM-CROPGRO-cotton model; climate warming; cotton phenology; thermal trend