Effect of application biochar and priming and foliar application with water and salicylic acid on physiological traits of dry land safflower

Safflower (Carthamus tinctorius L.) is one of the oldest oil seeds that due to deep and extensive root system is known for salt as well as drought tolerance. Seed priming with water and salt solution in plant increased germination percent and germination index under stress condition. The reported that seed priming with salicylic acid can protect the plants against abiotic stress. Salicylic acid has role protection in plants that are under environmental stress condition. The reported that salicylic acid increased plants resistance to biotic and abiotic stresses such as drought. Exogenous application of salicylic acid improved crops yield. The research showed that with application of salicylic acid increased the chlorophyll content. Biochar is a solid material that created from carbonization each type biomass includes weeds, crops residual and another wastage material with plant origin. Application of biochar increased available phosphorus, potash, magnesium and calcium content as compared without biochar. The reported that application of biochar retained water and nutrition and therefore could be increase wheat yield. The reported that application of biochar increased maize yield by 140% due to increasing of pH and nutrition in duration four years.

To evaluate the effect of biochar and seed priming with salicylic acid and water along with foliar application on physiological traits and oil yield of safflower in dry land condition, an experiment was performed as split- split plot based on randomized complete blocks design in three replications, at the Research Station of Islamic Azad University, Arak Branch, Iran, in during 2016-2017. Experiment factors were included biochar (wood, shoot and leaf of trees) in three levels of 0, 5 and 10 t/ha; seed priming in three levels of without priming, priming with water distillated and seed priming with .0.5mM salicylic acid and foliar application in two levels of foliar application with water and 1 mM salicylic acid. The cultivar safflower was ‘Esfahan native’. Seeds primed for 12 h at distillated water and salicylic acid solutions then dried at shade. Biochar was applied at 15 cm depth and under the seed, before from sowing and mixed with soil. Sowing done with 30 cm distanced rows with 15 cm spacing between plants in rows. The seeds were sown at 3-4 cm depth on middle March 2016. Foliar application of water and salicylic acid done in two stages of vegetative and reproductive growth at 17 h evening. Physiological traits measured in heading stage. Data were subjected to analysis of variance using SAS. Means were compared using the Duncan's multiple range test at 5% the confidence level.

Results showed that application of 5 t/ha biochar along with seed priming by salicylic acid increased the excise leaf water retention by 24.9 % compared to control. Application of 5 t/ha biochar decreased ion leakage by 15% and increased oil yield by 20% compared to control. Application of 10 t/ha biochar along with seed priming by salicylic acid increased the chlorophyll a content by 43.4% compared to control. The highest of carotenoids content was obtained from application of 5 t/ha biochar combined with foliar application of water. Application of 5 and 10 t/ha biochar increased the flower fresh wieght. The maximum of head harvest index was recorded from application of 5 t/ha biochar combined with foliar application of water or salicylic acid and also from application of 10 t/ha biochar combined with foliar application of salicylic acid.

The result this research showed that seed priming by water or salicylic acid along with foliar application and application of biochar by shoot water improve and decrease of damage due to stress condition, could be moderated the effect drought stress. Therefore seed priming by water or salicylic acid along with application of 5 t/ha biochar combined with foliar application of water or salicylic acid in two stage in duration of growth improved physiological traits and oil yield of safflower in dry land condition.