IRAQ JOURNAL OF AGRICULTURAL RESEARCH

A field experiment was conducted during the fall season of 2024 to study the effect of biochar application level and diameter on some soil chemical properties and some growth traits of broccoli plants. The study included two factors: the first was the application level (B1 and B2: 0.5 and 1%), and the second was the diameter (D1, D2, and D3: 0.5, 1, and 2 mm) of biochar. The experiment was designed according to a randomized complete block design (RCBD) with three replications, using sandy clay loam soil. Broccoli seedlings (cv. Jassmine F1) were transplanted on 1st October 2024.
Results indicated an increase in soil pH values, with treatment D1B2 recording the highest value (7.6), whereas D3B1 showed the lowest (7.26), compared to the control (7.18). Biochar addition also raised the values of electrical conductivity (EC), where D1B2 reached the highest value (2.66 dS m⁻¹), while D3B1 recorded the lowest 2.2 dS m⁻¹, compared to the control (1.93 dS m⁻¹). Adding biochar to the soil led to an increase in CEC values, as D1B2 achieving the highest value (20.39 cmol+ kg⁻¹), whereas D3B1 showed the lowest (19.25 cmol+ kg⁻¹), compared to the control (18.19 cmol+ kg⁻¹), on the other hand, sodium adsorption ratio (SAR) values decreased, as D3B1 recorded the lowest value (1.03 meq L⁻¹), while D2B2 recorded the highest (1.21 meq L⁻¹), compared to the control (1.65 meq L⁻¹). Furthermore, the effect of adding biochar to soil on some growth characteristics of broccoli plants was investigated where D1B2 produced the tallest plants, reaching 72.90 cm, while treatment D3B1 achieved the lowest value, reaching 64.40 cm. Treatment D1B2 achieved the highest number of leaves, reaching 30 leaves per plant-1, while treatment D3B1 achieved the lowest value, reaching 27 leaves per plant-1.

A field experiment was carried out at the First Agricultural Research Station of the University of Anbar, located in the Ramadi District, Al-Anbar Province, western Iraq, on sedimentary soil with a Silty Loam texture during the 2024 autumn season, to study the effect of some surface drip irrigation methods and the depth of added water on certain water parameters and the productivity of broccoli. The study included three irrigation methods: traditional surface drip irrigation )It( strip surface drip irrigation )Ir( and partial drying of the soil surface )Ip( in addition to three different depths of added water at levels of 50%, 60%, and 70% of the available water for the plant. The treatments were arranged in a factorial experiment according to a randomized complete block design. Broccoli cultivar MAX F1 was planted on 28/10/2024, and the American evaporation pan Class A was used for irrigation scheduling. The measurements included saturated hydraulic conductivity, basic infiltration rate, water consumption, application efficiency, total yield, and water use efficiency.
The results showed that the Ip method achieved the best improvement in the studied traits, recording the highest values of saturated hydraulic conductivity 5.48 cm.h⁻¹, basic infiltration rate 4.43 cm.h⁻¹, total yield 26.37 t.ha⁻¹, application efficiency 90.51 percent, and water use efficiency 31.47 kg.m⁻³. It was also found that the D0.50 depth produced the best results among the tested depths, with saturated hydraulic conductivity 5.03 cm.h⁻¹, total yield 26.15 t.ha⁻¹, application efficiency 90.40 percent, and water use efficiency 29.22 kg.m⁻³. Seasonal water consumption reached 50.97, 47.45, and 45.06 cm season⁻¹ for the D0.50, D0.60, and D0.70 depths respectively. The best interaction treatment was Ip with D0.50, which produced the highest values of saturated hydraulic conductivity 5.72 cm.h⁻¹, basic infiltration rate 4.70 cm.h⁻¹, total yield 30.47 t.ha⁻¹, application efficiency 91.20 percent, and water use efficiency 34.05 kg.m⁻³.