نشریه پژوهش های علوم کشاورزی پایدار
پیاپی 4 (زمستان 1400)

In order to evaluate the efficiency of non-chemical and chemical methods and their simultaneous use to control of weeds (Echinochloa Crus-galli, Amaranthus Retroflexus and Convolvulus Arvensis) in maize, a split plot experiment was conducted in the randomized complete block design in three replications and implemented at Varamin-Iran. The main factor (A) was non-chemical treatments consisted of three levels: AM: Irrigation before sowing (agronomic), AC: cultivator (mechanical) and A0 (without agronomic or mechanical operations). Sub-factor was (H) of chemical treatments include three levels of HFS (Foramsulfuron (at a rate of two liters per hectare, HNS (nicosulfuron at a rate of 1.5 liters per hectare), HA + G (atrazine and Gazaprim) and H0 (manual weeding by hand), respectively. The number of Amaranthus Retroflexus and Convolvulus Arvensis weeds (compared to the control) decreased by about 90% with the irrigation before sowing (Am) or cultivator (AC), and the increase in yield (compared to the control) was about 55-60%. While the non-chemical treatments (agro-mechanical) had no effect on reducing the number of Echinochloa Crus-galli weed. Nicosulfuron herbicide, similar to hand weeding (H0), controlled more than 90% of the Amaranthus Retroflexus and Convolvulus Arvensis weeds, but only 70% of the Amaranthus Retroflexus and Convolvulus Arvensis weeds. There was no significant difference in terms of corn grain yield (8000-8500 kg / ha) between hand weeding (H0) and nicosulforn herbicide (HNS) in plots in with agro-mechanical operations. However, in plots where agro-mechanical operations (A0) were not performed, hand weeding (H0) had 12.5% ​​higher corn grain yield compared to Nicosoluren herbicide application (HNS). Therefore, for Echinochloa Crus-galli, a combination of Irrigation-nicosulfuron and cultivator-nicosulfuron treatments is proposed.

Plant diseases and pest damages are one of the main factors that reduce both quality and quantity of final crops and restrict growers profit. Problems in photosynthesis and evapotranspiration may be taken place due to these pathogens. Efforts to apply chemicals or employing other methods for pest and disease control need precise field scouting and experts to identify the problem in a timely manner. Psylla pest is one of the most prevalent pests in pistachio orchards, which causes irreparable damage to orchards every year. In this study, the feasibility of employing machine vision to discriminate and count Pistachio Psylla was evaluated. Field data were collected from research orchards in three different time slots in summer based on pest infestation. The images were taken by various cellphone cameras with different resolutions in high and low controlled lighting conditions. The results of image-based count were compared with manual count by the expert technician in the laboratory. The effect of different light conditions and cameras with different resolutions on pest detection were evaluated by ANOVA test. There was no significant difference between manual count and digital count in high lighting conditions, but the differences in low lighting conditions were significant (p<0.05). The incorrect classification percentage values for low lighting conditions were higher than the ones obtained for high lighting conditions. This could be due to the lower quality of the images, in higher ISO values in low lighting conditions.The results showed that images taken by low-cost cameras in proper light intensity can easily replace the time-consuming and labor-intensive method of manual count.

To study the effect of culture medium, organic matter, and salinity on active compounds of lemon balm, a factorial experiment was conducted in completely randomized design with 3 replications. First factor (culture medium at three levels; compost+arable soil, vermicompost+arable soil, and compost+vermicompost+arable soil), second factor (organic matter; humic acid (HA) and effective microorganisms (EM) both 5 per 1000); and third factor (salinity; tap water, 40 and 80mM). Examination of essential oils by the GC method revealed the presence of 34 compounds. These compounds were affected by substrate and salinity. The major constituents of essential oils including Trans-carveol, Carvacrol acetate, Isoborneol, Isopulegol and γ-3-Carene were observed in the combined substrate of arable soil+compost+vermicompost, and the highest levels of 1,3,8-P-menthatriene, Citronellol, and γ-Terpinene were observed in the combined substrate of arable soil+compost. With increasing salinity, amount of Trans-carveol, Carvacrol acetate, γ-Terpinene, Isoborneol, Citronellol increased, and γ-3-Carene, Isopulegol and 1,3,8-P-menthatriene decreased significantly. The highest percentages of Trans-carveol (21.85), Isoborneol (12.90), Carvacrol acetate (11.78) were observed in the salinity of 80mM in combined substrate of arable soil+compost+ vermicompost. The highest percentage of Citronellol (11.12) and γ-Terpinene (9.87) were recorded under compost substrate. In the control and with a combined substrate of arable soil+compost, the highest percentage of compounds, including 1,3,8,P-menthatriene (9.93) was observed. Finally, the combined substrate of arable soil+compost+vermicompost caused the highest percentages of Isopulegol (8.98) and γ-3-Carene (8.47). Application of HA could increase the main constituents, in lemon balm.

The dust has become one of the most dominant environmental crises in some parts of the world especially in Sistan and Nimrooz in recent decades due to the increase in severity, duration and frequency of its occurrence. This study aims to evaluate the economic damage of the dust on the agricultural sector in Nimrooz city through the assessing of its impact on the agricultural sector. To collect required data, a questionnaires were developed in which not only some questions of people's willingness to pay for their support and protection to deal with dust were included but also a number of questions about their demographic characteristics were added. After data gathering step, we use Logistic regression model and perform the model by the maximum likelihood approach. The results showed that 82% of the surveyed people have shown some willing to pay to deal with dust damage. The average willingness to pay is 377060 Rial per month. The results also showed that the dust is the most important problem for the residents of Nimrooz city and most people in the region. They also want to actively participate in controlling dust besides their willingness to pay. In this regard, it is suggested that due to the importance and participation of people in dust control, policy makers use the results of this study for better planning to control dust pollution