A eld experiment was conducted during rabi seasons of 2015-16 and 2016-17 to study the accumulated growing degree days (GDD), helio-thermal unit (HTU), photo-thermal unit (PTU), heat use efciencies (HUE) at different phenological stages and performance of wheat (Triticum aestivum L.) varieties grown under different sowing dates. Results of present study revealed that the crop sown on 20th October required maximum calendar days, growing degree days, photo-thermal unit and helio-thermal unit for tillering, owering, earing and maturity which was signicantly reduced with subsequent delay in sowing time. The grain yield recorded in 20th November (4065 kgha-1) was statistically at par with 5th November yield (3863 kgha-1). The signicant reduction in grain yield on varieties was recorded when sowing was delayed beyond 20th November. Among the varieties 'VL-907' produced highest grain yield(3771 kgha-1) which was statistically on par with 'VL-829' (3726 kgha-1). The early and timely sown wheat variety like VL-829 and VL-907 took highest calendar days, GDD, HTU and PTU for earing and maturity. The variety 'VL-907' recorded the highest grain yield (4196 and 4168 kgha-1) at 5th and 20th November sowing as compared to all other sowing dates.

A field experiment has been conducted in Cotton-Wheat cropping system for three cropping cycles, wherein we evaluated a total of five treatments (Control, Sub-soiling at 1.0 m, Sub-soiling at 1.5 m, Cross sub-soiling at 1.0 m and Cross sub-soiling at 1.5 m) in complete randomized block design to find out the effect of sub-soiling on the physical properties of soil and root parameters of cotton in Indian Punjab, where heavy machinery usage in farm operations is causing soil compaction leading to ill effects. Data elucidated that any level of sub-soiling not only improved soil physical properties by reduction in bulk density but also enhanced steady state infiltration rate as compared to control. Data also revealed that root length, fresh root weight plant-1 and dry root weight plant-1 of cotton exhibited significant differences in sub-soiled plots versus control for initial two years of experimentation but trivial differences existed thereafter. Consequently, both cotton and wheat crop resulted in higher yield owing to above mentioned reasons. The field data set is made publicly available to enable critical or extended analysis.