An association of biotic and abiotic stress resistance has existed with modifying the genetic makeup of plant cells, and as a result, variations occur in some physiological and biochemical processes. Relatedly, the collection of bread wheat (Triticum aestivum L.) germplasm and its assessment through morphological, genetic, and physiological parameters are practically significant. Studying the influence of the genotype-environment on the physiological and quantitative characteristics of bread wheat germplasm in Uzbekistan resulted in the environment influencing the wheat genotypes, with a hydrothermal coefficient of Ij = 1.43 in 2017. It gave the average grain yield from all the wheat nurseries at 6.84 t/ha. Meanwhile, in 2019, the hydrothermal coefficient was Ij = 0.69 with a grain yield of 6.77 t/ha. However, when the hydrothermal coefficient decreased to a negative value (Ij = -2.8), the average yield decreased to 6.48 t/ha. The identification of wheat genotypes succeeded according to environmental plasticity (bi) and stability coefficient (Si2) indicators, i.e., K-64 (bi = 0.5, Si2 = 1.8), K-74 (bi = 0.7, Si2 = 1.9), and genotype K-100 (bi = 0.4, Si2 = 0.9).

Keywords: Bread wheat (T. aestivum L.), genetic attributes, morphological traits, physiological processes, leaf, carotenoid, grain yield

Key findings: Regression analysis showed a one-mg increase in total chlorophyll content raised the productivity of 50 selected bread wheats (T. aestivum L.) genotypes by 12%. The three-year average of total chlorophyll ranged from 3.34 to 2.03 mg/g, with productivity also significantly reduced in wheat genotypes with low chlorophyll content.

A field experiment on olive (Olea europaea L.) saplings examined the influence of the Acadian seaweed extract and organic humic acid, carried out from March to November 2022 in an orchard located in Jazirah, Ramadi Region, Iraq. The study aimed to determine effects of foliar application of seaweed extract Acadian and organic fertilizer humic acid with concentrations of 0, 250, 500, 750, and 1000 mg L^-1 on olive saplings’ foliage. Results showed spraying coefficients with individual treatments of Acadian and Humic fertilizers at the concentration of 1000 mg L^-1 significantly outperformed most studied traits. These provided the highest averages for main stem height (92.93 and 98.67 cm), main stem diameter (6.193 and 6.060 mm), leaf number (479.2 and 397.7), leaf area (602.4 and 455.1 cm²), leaf chlorophyll content (73.60 and 75.73 SPAD), dry weight of vegetative parts (97.87 and 91.40 g), and root system (23.13 and 18.07 g), respectively. The interactions of both factors at 1000 mg L^-1 concentration were superior on olive saplings for the main stem height (131.00 cm), main stem diameter (7.067 mm), leaves seedling^-1 (670.3), leaf area (689.0 cm²), leaf chlorophyll content (83.67 SPAD), dry weight of vegetative parts (122.33 g), and root system (28.33 g). The study concluded, based on results, that foliar fertilization, whether with biological or organic fertilizer, contributes positively and effectively to improving olive seedlings’ growth.

Keywords: Olive (O. europaea L.), Acadian seaweed extract, organic Humic, nutrients, vegetative, root system

Key findings: The results revealed a greater improvement in growth and morphological traits of olive (O. europaea L.) saplings with foliar application of organic fertilizers at a concentration of 1000 mg L^-1.

A biological experiment proceeded on yellow corn (Zea mays L.) in plastic pots during the agricultural season on August 4, 2021, which included adding organic matter (0% and 5%) and bentonite mineral (0%, 10%, and 20%) of soil weight and potassium (0, 50, and 100 kg ha^-1) as potassium sulfate. After 90 days of planting, the amount of soluble and exchangeable potassium measured revealed results that adding organic matter with bentonite minerals increased soluble potassium by 38.46%. Meanwhile, exchangeable potassium decreased by 1.61% and dry matter increased by 6.5%. As for adding bentonite, the 20% level was the most effective compared with 0% and 10%, in reducing soluble potassium by 25% and 50%. It also increased exchangeable potassium by 1.62% and 2.45% and dry weight of the plant by 95.04% and 48.32%. As for the effect of the added potassium levels, the results showed 100 kg ha^-1 was superior to 50 and 0 kg ha^-1 in soluble potassium (92.86% and 440%, respectively). The drained potassium was the highest at the level of 100 and 50 kg ha^-1 (5.88% and 5.04%) in the direction of the contact line, and 100 kg ha^-1 was superior to 100 and 50 kg ha^-1 in the dry weight of the plant (9.85% and 4.80%). The results of the double and triple interaction showed significant differences.

Keywords: Yellow maize (Z. mays L.), organic matter, bentonite, potassium fertilizer, growth traits

Key findings: The addition of organic matter and bentonite to sandy soils can improve potassium availability and reduce the values of exchangeable potassium, aside from improving the yellow maize corn (Z. mays L.) growth.

The field experiment on maize (Zea mays L.) during the autumn of 2020 revealed the effects of irrigation periods and mulching on its growth and yield-related traits. The study, held at the Bad’at al-Musayyab region, Babylon province, Iraq, had the experiment laid out in a randomized complete block design (RCBD) with factorial arrangement, two factors, and three replications. The first factor was the irrigation intervals (4, 8, and 12 days), while the second comprised two mulching methods (straw mulching and no mulching). The irrigation intervals, mulching treatments, and their interactions revealed significant differences for most growth and yield-related traits in maize. The least irrigation interval (four days) excelled in achieving the highest mean values for plant height (195.00 cm), leaves per plant (16.31), leaf area (697.9 cm²), chlorophyll index (63.16 SPAD), ears per plant (1.88), grains per ear (602.5), and grain yield (12.55 t ha^-1), compared with the maize crop irrigated with a 12-day interval. The latter recorded the lowest means for the above-mentioned traits. The soil mulching treatment also excelled for the traits compared with non-mulching, which recorded the minimum values.

Keywords: Maize (Zea mays L.), irrigation intervals, soil mulching, interactions, growth and yield traits, physiological traits

Key findings: Maize (Zea mays L.) planting with straw mulching and irrigated every four days, promoted the growth and, eventually, boosted the yield components and grain yield of corn.

The research aimed to prepare a theoretical vision, including a set of proposed standards for developing work in Agricultural Extension Centers in the Central Governorates (Baghdad, Diyala, Babylon, Al-anbar, and Salah al-Din), within seven important guiding areas. Using the descriptive approach to conduct this study, the sample community included all agricultural extension workers working in research centers of central Iraq governorates, totaling 95 respondents. The two-part questionnaire served as a tool for collecting data from the respondents. The first part represented opinions of agricultural extension agents about the extent of application and adoption of suggested standards in the work of agricultural extension centers. Meanwhile, the second part included the respondents’ opinions about the degree of their approval of the proposal to develop the extension centers. The study concluded a large proportion of the respondents believe a weakness existed in the level of application of the recommended standards in the operation of the agricultural extension centers. It is evident in not adopting the principle of decentralization when formulating the goals of the extension centers.

Keywords: Agricultural Extension Centers, Central Governorates of Iraq, theoretical vision, research community, extension agents, decentralization

Key findings: A significant weakness in the coordination process and cooperation with relevant authorities exist. Similarly, a limitation occurs in the integration of many parties with common goals, with the objectives of extension programs not based on real data, surveys, and studies. It was evident most of the sample members agreed with the standards proposed by the policy and objectives of the counseling centers.

The study intended to find out the main cause of cowpea damping-off and root rot disease. Separating a group of fungi comprised Fusarium solani, Rhizoctonia solani, and Macrophomina phaseolina. Findings of the field survey revealed fungus F. solani appeared in all isolated samples. The testing of pathogenicity of all isolated fungal isolates led to choosing the F. solani (Fs2) isolate as the most pathogenic in the experiment’s implementation. The biological resistance of Bacillus subtilis and fungus Trichoderma harzianum bore testing, with their high efficiency observed in inhibiting the pathogenic fungus isolate. Biological bacteria with the highest concentration of 10^-7 appeared with an inhibition rate of 82.20%. The results showed effectiveness of the chemical pesticide in all the concentrations and were highly successful. The wooden canopy showed the effectiveness of the biological resistance in inhibiting the pathogenic fungus. Results showed interaction of the fungus with bacteria reduced the rate and severity of infection to zero. A significant superiority of the biological resistance elements was notable in reducing severity of infection compared with pathogenic fungus alone. The field results confirmed the woody canopy for the efficiency of the biotic resistance elements in reducing the rate and severity of infection, raising the growth of cowpea plants.

Keywords: F. solani, T. harzianum, B. subtilis, cowpea damping-off

Key findings: This study aimed to reveal the effectiveness of biological and chemical resistance elements in inhibiting the pathogenic fungus F. solani, which causes the death of cowpea plants, as well as, improving the growth parameters of the plants.

The presented study determined the effects of foliar application of marine algae extract and Humax on the pomegranate (Punica granatum L.) seedlings beneath the plant canopy, carried out in 2023 at the University of Kerbala, Kerbala, Iraq. The experiment layout was in a randomized complete block design (RCBD) with factorial arrangement, three factors, and three replications. The first factor was the two pomegranate cultivars (Wonderful and Slimi), the second factor was marine algal extract concentrations (0, 1.5, and 3 ml L^-1), while the third was the Humax levels (0.25, 0.25, and 0.50 g L^-1). Pomegranate cultivar Wonderful showed the highest content of chlorophyll, carbohydrates, nitrogen, phosphate, and potassium, compared with the cultivar Slimi. Marine algal extract (3 ml L^-1) and humax (0.50 g L^-1) also performed better and improved the biochemical composition of the pomegranate. Cultivars in interaction with marine algae extract also performed well and improved the traits. However, cultivar Wonderful with marine algal extract (3 ml L^-1) and humax (0.50 g L^-1) had the highest averages for the chlorophyll, carbohydrates, nitrogen, phosphate, and potassium. The marine algae extract and Humax binary interaction considerably affected the study variables in the pomegranate.

Keywords: Pomegranate (P. granatum L.), marine algae extract, Humax, interaction, physiological and biochemical traits

Key findings: The pomegranate (P. granatum L.) cultivar Wonderful, in integration with marine algae (3 ml L^-1) and humax (0.50 g L^-1), achieved the highest averages for physiological and biochemical traits.

A study, carried out in 2023 at the University of Kerbala, Iraq, aimed to assess the effects of natural and synthetic growth hormones on the vegetative characteristics of two pomegranate (Punica granatum L.) cultivars. The experiment layout had a randomized complete block design (RCBD) with factorial arrangement, two factors, and three replications. The first factor included combinations of natural and chemical growth regulators, while the second comprised stem cuttings of two pomegranate cultivars, Yamani and Bashkan. The results showed cultivar Yamani was superior for vegetative branches (4.110), the number of leaves (341) per seedling, and leaf area (988 cm²). The triple interaction of indole butyric acid (IBA 0 mg L^-1), moringa leaf (M1), and licorice root (L1) (B0M1L1) extracts provided superior performance on the average height and diameter of vegetative shoots (49.500 cm and 2.510 mm, respectively). The interaction of indole butyric acid (IBA 0 mg L^-1), moringa leaf (M1), and licorice root (L0) (B0M1L0) extracts also excelled in the average number of branches and chlorophyll content (4.670 branches seedling^-1 and 0.276 mg g^-1, respectively).

Keywords: Pomegranate (Punica granatum L.), cultivar stem cuttings, indole butyric acid, moringa leaf extract, licorice root extract, growth and physiological traits

Key findings: The pomegranate cultivar Yamani showed superiority in most traits than the other cultivar Bashkan. The interaction of natural and synthetic growth regulators (B1M1L0) was superior in seedling height, branch diameter, and leaf area. For the number of branches and leaves per seedling, the combinations B1M0L0 and B0M1L1 outshone with the highest averages, while the combination B0M1L0 led for chlorophyll content.

The presented experiment on grape (Vitis vinifera L.), carried out in the growing season of 2022, transpired in the orchard of the Department of Horticulture and Garden Engineering, College of Agriculture, Tikrit University, Tikrit, Iraq. Two factors comprised the study. The first factor was two grape cultivars, i.e., Halwani and Kamali, while the second involved foliar application of sugar alcohol (mannitol) with three levels (0, 4, and 8 ml L^-1). The study aimed to evaluate the grape cultivars, impact of sugar alcohol, and their interaction on the yield characteristics and qualitative traits. The vine plants planting had dimensions of 2 m × 4 m, with the experiment having the split-plot design. The trial included six treatments, randomly distributed into three replicates, with two vines per experimental unit, totaling 36 vine plants. The results showed adding sugar alcohol solution (8 ml L^-1) led to a significant enhancement in the number of clusters, cluster weight, total suspended solids, total sugars, total acidity, and anthocyanin content. The grape cultivar Halwani outperformed the other cultivar Kamali for cluster weight, total yield, total sugars, and anthocyanin content, while cultivar Kamali excelled in the number of clusters and total acidity.

Keywords: Grape (Vitis vinifera L.), grape cultivars, sugar alcohol, yield quantity, qualitative traits, sugars and anthocyanin content

Key findings: Superiority of the sweet grape (Vitis vinifera L.) cultivar Halwani over the non-sweet cultivar Kamali was evident in cluster weight, total sugars, and anthocyanin content. Conversely, the non-sweet cultivar Kamali outperformed the sweet cultivar Halwani for cluster number and total acidity. However, both grape cultivars revealed nonsignificant differences in total suspended solids and yield quantity.

A field experiment commenced in Hindiyah District, Kerbala, Iraq, during the growing season of 2022–2023, to evaluate the effect of Azotobacter and orange (Citrus sinensis L.) peel treatments on the growth and yield characteristics of fenugreek (Trigonella foenum-graecum L.). The experiment had a randomized complete block design with factorial arrangement of two factors and three replications. The first factor included four levels of the Azotobacter bacteria (control, 20, 50, and 100 g L^-1), while the second comprised four concentrations of orange peel extract as a soil amendment (control, 100, 150, and 200 g L^-1). The treatment with Azotobacter (100 g L^-1) indicated significant effects and provided the highest mean values of the compounds, quercetin, diosgenin and trigonelline (33.20, 36.57, and 37.05 mg g^-1, respectively). The results also revealed the remarkable effect of the treatment with orange peel (200 g L^-1), which gave the maximum values of the quercetin, diosgenin, and trigonelline (31.99, 35.73, and 35.91 mg g^-1, respectively). The interaction effects of the Azotobacter and orange peels were also substantial for all the traits of fenugreek (T. foenum-graecum L.) under study.

Keywords: Fenugreek (T. foenum-graecum L.), Azotobacter, orange peels, secondary compounds, growth and yield traits

Key findings: In fenugreek (T. foenum-graecum L.), the treatments with Azotobacter (100 g L^-1), orange peels (200 g L^-1), and their interactions indicated significant effects to improve the concentrations of secondary metabolism compounds and yield parameters.