h.r. chaghazardi

Peanuts (Arachis hypogaea L.) possess significant commercial and nutritional value (Gulluoglu, Bakal, Bihter, Cemal, & Arioglu, 2016). However, this plant is highly susceptible to weed competition due to its slow canopy extension, dormant growth habit, and lengthy critical weed control period (Everman, Burke, Clewis, Thomas, & Wilcut, 2008). Consequently, effective weed control measures are crucial for successful peanut production. Furthermore, implementing appropriate planting patterns can reduce competition among peanut plants, enhance solar radiation absorption and other growth resources, and ultimately lead to increased crop yield (Bihter, Bakal, Gulluoglu, & Aroglu, 2017). Therefore, the objective of this study was to assess the impact of planting pattern and the integration of pre- and post-emergence herbicides with hand weeding on the yield and yield components of two peanut cultivars, specifically in the climate of Kermanshah, for the first time.

To investigate the impact of weed management and planting patterns on the yield and yield components of different peanut cultivars in the weather conditions of Kermanshah, a factorial experiment based on a randomized complete block design was conducted. The study took place in 2022 at the research field and physiology laboratory of the agricultural campus and natural resources of Razi University. The experiment consisted of three factors: Peanut cultivars (NC2 and NC7), Planting patterns (P1: row and plant spacing of 50 cm × 25 cm, and P2: 75 cm × 18 cm), Weed control treatments (M1: Two rounds of weeding combined with the application of Trifluralin 48% EC (796 g a.i.ha-1), Bentazon 48% SL (960 g a.i.ha-1), and Haloxyfop-r-methyl 10.8% EC (75 g a.i.ha-1), M2: Two rounds of weeding along with the use of Trifluralin (1233 g a.i.ha-1), M3: Two rounds of weeding combined with the use of Haloxyfop-r-methyl and Bentazon, M4: Complete weeding, and M5: Weed-infested treatment) Measurements of plant dry weight, seed dry weight, and pod dry weight per square meter were conducted using a precision scale. Additionally, the number of seeds and pods per square meter were counted. To assess seed size, photography and image processing using JMicrovision software were employed. The analysis of variance was performed using the GLM procedure in SAS ver. 9.4.

The results of the experiment revealed several significant findings. The NC7 cultivar exhibited the highest plant dry weight per square meter (620.83 g), showing a 37.37 percent increase compared to the NC2 cultivar (452.11 g). Similarly, the NC7 cultivar also demonstrated the highest pod dry weight per square meter (412.80 g). Among the weed control treatments, the M4 treatment resulted in the highest plant dry weight per square meter (678.79 g), which was about 416 percent higher than the M5 treatment (13.163 g). The M4 × P1 treatment combination produced the highest seed dry weight per square meter (291 g), while the P1 planting pattern yielded the highest pod dry weight per square meter (427.67 g). Notably, weed control treatments and the P1 planting pattern promoted larger seed size. Overall, effective weed control enhanced the studied traits of peanut. Although no significant differences were found among the weed control treatments, the combination of Trifluralin 48% EC (796 g a.i.ha-1) with a row and plant spacing of 50 cm × 25 cm is recommended for Kermanshah due to its lower herbicide consumption and comparable efficacy to other weed control treatments.

The results of the study indicate that optimizing row distances can play a crucial role in improving the yield and yield components of peanuts. Furthermore, the implementation of effective weed control measures, including both hand weeding and herbicide application, resulted in a significant increase in peanut yield. These findings highlight the importance of considering row distances and weed management strategies in peanut cultivation. Based on the favorable yield production of peanuts in the Kermanshah climate, it can be considered as a promising and viable crop for inclusion in summer rotations in the region. Further research and investigations should be undertaken to provide more comprehensive recommendations and promote the cultivation of peanuts in Kermanshah. This crop has the potential to contribute to agricultural diversification and enhance the profitability of farmers in the area.

Optimum yield production under rainfed cultivation directly depends on the amount of rainfall and moisture storage in the soil. The tillage system directly influences soil moisture retention as well as the soil’s physical and chemical properties. Selecting the appropriate tillage system can significantly impact crop yields. Oilseeds are particularly important among crops, representing the second-largest food reserve in the world after grains. These products are rich in fatty acids. Today, the oil extraction and production industry is one of the most strategic industries in most countries. Iran has vast arable land and favorable conditions for cultivating oilseeds. However, according to available statistics, over 80% of the country's oil needs are met through imports. Given the increasing demand for higher-quality oil products and the challenges posed by climate issues, such as recurring droughts, cultivating and developing crops with lower water requirements and greater resilience appears to be a promising solution. Implementing effective management practices and appropriate fertilizers aligned with conservation agriculture could help increase crop yields while maintaining and improving long-term soil quality. To explore the potential of oilseed cultivation, an experiment was conducted to examine the effects of tillage and fertilization on the yield and yield components of safflower under rainfed conditions.

This experiment was carried out as split plots based on random complete blocks design, with three replications under rainfed conditions. The treatments included tillage systems (conventional tillage, reduced tillage, and no-tillage) as the main factor and NPK fertilizer (a mixture of urea, triple superphosphate, and potassium sulfate) at four levels of zero, 33, 66, and 100% as a secondary factor. Potassium and phosphorus fertilization and 50% of nitrogen fertilizer were used at the same time as planting, and the remaining 50% of nitrogen fertilizer was used four months after planting. Each block had three main plots; the distance between each block was 3 meters, and between the main plots was 2 meters. In each main plot, four sub-plots were created, and the distance between the sub-plots was 1 meter. The area of the main plots was 21 × 15 meters, and the area of each sub-plot was 4.5 ×15 meters. The amount of seed used for safflower was 25 kg per hectare. The safflower seeds were sown in 5 rows and planted at a distance of 50 cm and a distance between plants of 10 cm. At all stages of planting, maintenance, and harvesting, agricultural management followed the traditional practices of the study area, as performed by the local farmers. The final sampling, or harvesting, was carried out manually at the physiological maturity stage. Before conducting variance analysis, a normality test was performed on the data. In this research, the LSD test was used to compare the mean at the 5% probability level, Excel software was used to draw graphs, and SAS 9.4 software was used to analyze the data.

The research showed that the traits examined, including leaf area index, dry matter content, thousand seed weight, seed yield, and biological yield, were affected by the tillage system, fertilizer, and their interaction effect. The highest safflower seed yield of 195.6 g/m2 was obtained from the fertilizer ratio of 33% and conventional tillage, and the lowest seed yield of 116.2 g/m2 was obtained from no-tillage and no fertilizer use. The results indicated that the conventional tillage system outperformed both reduced tillage and no-tillage systems. In reduced and no-tillage systems, the changes in the leaf area index of the safflower plant were similar, with the 100% fertilizer application under reduced tillage having a more pronounced effect compared to no-tillage. Additionally, in the absence of fertilizer in the no-tillage system, the leaf area index was lower. Fertilizer application increased the plant's biological yield, but its impact was greater under conventional tillage compared to reduced and no-tillage systems. Applying 33% of the required fertilizer in the conventional tillage system resulted in the highest biological yield for safflower, leading to a 94% increase in biological performance compared to the control.

In most of the examined traits, the application of 33 and 66% of the fertilizer requirement caused the best results, and the 100% fertilizer ratio left adverse effects, which indicates the lower fertilizer requirement of this cultivar in the studied conditions compared to cultivars in other regions. Since the research was conducted in rainy years, conventional tillage was better than low tillage. It is suggested that this plant's production amount be evaluated under different irrigation conditions and moisture limitations so that tillage systems and management methods can be examined and selected more carefully.