Wheat is one of the most important cereal crops which contribute to the food security not only in India but also around the globe. The traditional agricultural practices, though has enhanced its productivity, has resulted in modern day problems such as soil health deterioration, excessive use of natural reserves leading to their depletions well as reduced profitability to the farmers. Also increasing interest is being witnessed all over the world for natural farming which aims to achieve higher productivity with minimal use of resources explicitly avoiding external ones. Conflicting results have been reported from across the globe regarding the performance of varieties under different cultivation practices. Hence, it is important to identify wheat varieties that can be successfully cultivated under varying degree of tillage practices as well as under natural farming practices. Since, developing varieties suitable for conservation agriculture practices is time consuming, the focused on identifying varieties out of the existing popular ones, that can perform well under varying tillage practices. Hence, the present investigation was aimed at meeting the demand of the stakeholders for suitable variety for conservation tillage till the time the specific varieties for these conditions are developed and popularized. The findings of this investigation clearly indicated the superiority of conventional tillage, which involved both primary and secondary tillage at sowing, as compared to reduced tillage, zero tillage, and natural farming. Among wheat varieties evaluated Him Palam Gehun 2 and Central Wheat (HS 562) performed better than HPW 369. Also all the three varieties evaluated behaved in a similar manner under different cultivation practices, Nutrient analysis showed that conventional tillage resulted in significantly higher nitrogen, phosphorus, potassium, zinc, and iron contents in both grain and straw while among varieties Central Wheat HS 562 and Him Palam Gehun 2 exhibited higher contents for most of these nutrients. From the present investigation it could be concluded that conventional tillage results in better wheat productivity in the short term as compared to other conservation tillage practices and natural farming though the long term impact of these tillage practices on productivity and quality of wheat as well as on soil health needs to be investigated. Further the study also indicated the inability of natural farming practices to give satisfactory yields of a high nutrient requiring crop like wheat. Also, all the varieties evaluated in this investigation exhibited similar results under different cultivation practices indicating the urgent need to develop varieties having specific characteristics that can perform better under conservation agriculture practices.

Background The date of sowing is a non-monetary input factor that plays a crucial role in field crop management. Based on the sowing time, management practices of crop production affect crop growth, development, and yield. Under varied environmental conditions, this factor may be useful in addressing low yields and combating/escaping stresses either due to diseases or due to any unfavourable environment. Results A field experiment was conducted during the rabi season of 2017–18 and 2018–19 to study the accumulated growing degree days (GDD) and performance of six wheat cultivars (HS 562, HD 2967, HD 3086, HI 1544, MACS 6222 and WR 544) under four sowing dates (5th November, 25th November, 15th December and 5th January). The study revealed that 5th November is the best date for sowing resulting in higher pooled grain yield of 4.85 Mg ha⁻¹ and 3.94 Mg ha⁻¹ at Bajaura and Malan, respectively. Significant reductions in the grain yield and yield attributes were observed when the date of sowing was set beyond 5th November. Among the cultivars tested, HS 562 gave a significantly higher pooled grain yield of 4.46 and 3.75 Mg ha⁻¹ at Bajaura and Malan, respectively. Pooled data on physiological maturity revealed that variety HS 562 took the highest calendar days (168 days) and GDD (1573.42 °C days) to attain physiological maturity at Bajaura while at Malan HI 1544 and HD 3086 took the highest calendar days (156 and 155 days, respectively) and GDD (2055.41 and 2051.81 °C days, respectively) to attain their physiological maturity. Conclusion From the study, it can be concluded that the early date of sowing provides the crop with ample duration to accumulate growing degree days resulting in a higher accumulation of photosynthates resulting in significantly higher yield attributes and grain yield. Therefore, 5th November is recommended as the best time for sowing of wheat crop whereas the sowing must not be delayed beyond 25th November. HS 562 was superior among the cultivars and is recommended for Malan and Bajaura regions for attaining higher yield.