Effect of seeding rate and spraying different levels of kinetin on some physiological and growth traits of barley (Hordeum vulgare L.)

A field experiment was conducted in the Al-Jazeera region (northwest of Tikrit city- Salaheddin governorate ) with the aim of studying the effect of seeding rates of the barley crop (Shu'a) and spraying plants with different levels of kinetin acid concentration on some physiological traits and vegetative growth. The factorial experiment was carried out using a fully randomized block design (factorial experiment) with three replications, with two factors: the first included two levels of seed quantities (160, 180) kg ha-1, and the second factor was the spraying of the growth regulator kinetin at three levels. (75, 50, and 0) mg L-1, and the results showed that the seed rate (160) kg ha-1 was superior to the duration of dry matter production by a difference of (12.92%), The chlorophyll content of the leaves increased by (12.05%), and the seed rate (180) kg ha-1 exceeded the height of the wheat plant by (6.95%) cm, while no significant differences were observed in leaf area and seeding rates. The concentration of the growth regulator kinetin was recorded as (75) mg L-1, which was significantly higher than the rest of the concentration levels of the regulator in both the duration of dry matter production and the two characteristics of plant height, with a difference of (18.49%) and leaf area, with a difference of (51.12%), respectively. Both the absolute growth rate and the chlorophyll content of leaves for the two concentrations (75 and 50) mg L-1 recorded a significant difference from the concentration (0) without addition, with an average difference of (21.24 and 25.98). %) for the two classes respectively.