s. mahmoodi

The economic importance of quinoa is not only due to the possibility of using the seeds as a food product characterized by a similar composition and use as consumer cereals but the species can also be managed as a leafy vegetable with high nutritional value and similar uses, such as, for example, spinach. Drought is another environmental stressor for plants subjected to severe water stress, especially in semi-arid and arid environments. Water scarcity poses a considerable challenge to crop production, leading to a notable reduction in crop yield. Quinoa, however, boasts low water requirements and demonstrates resilience in drought conditions. Even during dry periods, quinoa can effectively sustain leaf area and regulate photosynthetic activity. This resilience is facilitated by structural characteristics such as small, thin-walled cells, tissue flexibility, low osmotic potential, and controlled leaf area reduction through dehiscence. Other quinoa features for sustaining turgor pressure through osmotic adjustment during drought stress include inorganic ion buildup (e.g., Ca, K, and Na) and improved organic element synthesis (carotenoids and proline). Quinoa genotypes have several drought-resistance mechanisms, enabling this crop to grow and develop under severe drought conditions. 

To evaluate the effect of moisture levels on some quinoa cultivars biochemical traits, four separate experiments were conducted in a factorial layout based on randomized complete block design with three replications in two regions (Birjand and Sarbisheh) and two planting dates (March and July/August) in 2018-2019. The experimental factors included five moisture levels (25, 50, 75, 100, and 125% of crop water requirement) and three quinoa cultivars (Titicaca, Giza1, and Redcarina). Some quinoa physiological and biochemical traits were evaluated by composite analysis at the 50% flowering stage and the effects of planting date and location were considered fixed.

The results showed that in August/July cultivation, the characteristics of RWC, electrolyte leakage, sodium percentage, potassium percentage, chlorophyll a, carotenoids, proline content, and total soluble carbohydrate of leaves were increased by 17.10, 74.62, 95.51, 31.9, 3.53, 38.65, 94.19 and 9.30% respectively and chlorophyll b content decreased by 13.15% compared to March culture. Also, in Sarbisheh, RWC, electrolyte leakage, potassium percentage, and leaf carotenoids are respectively 3.53, 38.65, 94.19 and 9.30% more than Birjand, but sodium percentage, chlorophyll a, chlorophyll b, proline and total soluble carbohydrates of leaves were 4, 1.88, 15.67, 51.02 and 30.41% less than Birjand, respectively. In most of the studied traits, the Giza1 cultivar had higher quality traits. Severe water scarcity resulted in an elevation of certain biochemical traits in quinoa leaves. Specifically, as moisture levels decreased from 125% to 25% of the water requirement, there was a significant increase in electrolyte leakage, sodium and potassium percentages, chlorophyll a and b, carotenoids, proline, and total leaf soluble carbohydrates by 24.50%, 37.84%, 35.89%, 24.83%, 59.12%, 48.75%, 51.58%, and 36.71%, respectively. However, the relative water content (RWC) decreased by 17.70%. Notably, there were no significant differences observed between the 125% and 100% levels of water requirement for most of the analyzed traits.

In general, with the significance of the triple interaction of planting date × location × cultivar, as a result, the reaction of each variety depends on the planting date and location of its planting. But in general, most of the quinoa leaf physiological and biochemical traits increased in August/July cultivation. In Birjand, due to the higher average temperature and other climatic parameters compared to Sarbisheh, and probably understanding the heat stress, traits such as photosynthetic pigments, proline, and soluble carbohydrates had higher values. In this research, the Giza1 was superior to the other two cultivars, and moisture stress caused a significant decrease in the water content of the leaves and a significant increase in quinoa leaves quality traits.

Deficit irrigation offers a solution for optimizing crop production under water stress conditions, albeit with an initial reduction in yield per unit area. Employing deficit irrigation aids in farm management in scenarios where land availability isn’t constrained, enabling the determination of optimal cultivation patterns while conserving water consumption. However, deficit irrigation may influence plant growth and development by inducing drought stress. Due to several capabilities, quinoa shows resistance to solar radiation, temperature, water availability, and atmospheric CO2 concentration, which makes it possible to cultivate it in different agricultural areas. Quinoa also has a great capacity for cultivation in dry and low-water soils. Although growth analysis sometimes provides valuable clues, it does not provide any physicochemical information related to the environmental reactions of plants; in other words, the main benefit of many quantities involved in growth analysis is to provide an accurate estimate of the ability and efficiency of the plant in the community at certain time intervals. In general, growth analysis evaluates the system based on the results of physiological manifestations. The purpose of this research was to evaluate the physiological growth analyses of three quinoa cultivars under different moisture levels in summer and spring planting dates in the South Khorasan region.

To evaluate the physiological traits of three quinoa cultivars under deficit irrigation conditions, four separate experiments were conducted using a factorial layout based on a randomized complete block design. These experiments included three replications and were carried out in two regions (Birjand and Sarbisheh) during two planting dates (March and July) in 2018-2019. The experimental factors consisted of five moisture levels (ranging from 25% to 125% of crop water requirement) and three quinoa cultivars (Titicaca, Giza1, and Redcarina). To compare the cultivars and assess the impact of humidity levels, several physiological indices—such as leaf area index (LAI), crop growth rate (CGR), relative growth rate (RGR), and net assimilation rate (NAR)—were studied. Regression curves were fitted to the data from all four experiments separately, and separate analyses of variance were also performed for each sampling time.

The trend of changes in the leaf area index (LAI) showed that the time needed to reach the maximum LAI was observed between 106 to 107 days after emergence in March and between 73 to 76 days after emergence in July in Birjand, respectively. In Sarbisheh, the maximum LAI was observed on day 104 after emergence in March and between 65 to 72 days after emergence in July. In March, in both studied areas, Redcarina had the highest LAI values (4.5 in Birjand and 6.7 in Sarbisheh), along with the maximum crop growth rate (CGR) of 17.93 g m-2 day-1 in Birjand and 20.63 g m-2 day-1 in Sarbisheh. Conversely, in July, Giza1 exhibited the highest LAI (6.4 in Birjand and 6 in Sarbisheh), along with the maximum CGR of 19.32 g m-2 day-1 in Birjand and 18.11 g m-2 day-1 in Sarbisheh. Additionally, the highest relative growth rate (RGR) and net assimilation rate (NAR) at the beginning of the growing season in March were observed for Redcarina, while in July, Giza1 demonstrated the highest RGR and NAR in both studied areas. Considering the effect of humidity levels, the highest levels of LAI, CGR, RGR, and NAR indices were observed at the 125% water requirement level. Specifically, the maximum LAI values in March (in Sarbisheh and Birjand) and August (in Sarbisheh and Birjand) were 8.2, 5.3, 6.5, and 7.2, respectively. The maximum CGR values were 28.78, 23.56, 22.96, and 26.18 g m-2 day-1, respectively. Furthermore, the highest RGR at the beginning of the growing season ranged from 0.189 to 0.214 g g-1 day-1, and the highest NAR at the beginning of the growing season ranged from 6.16 to 10.22 g m-2 day-1. Conversely, the lowest values of these indices were observed at the 25% water requirement level.

Overall, Redcarina, cultivated in March, and Giza1, cultivated in July, exhibited the most favorable growth analysis indices and grain yield compared to other cultivars. Additionally, deficit irrigation resulted in a decrease in all of these indices and grain yield.

Intercropping system is the growth of two or more crops at the same time, which can lead to decreases in the risk of total crop reduction and increases in yield with control of weeds. Quinoa (Chenopodium quinoa willd.) is a pseudo cereal with high nutritional value which is approximately a new crop in Iran. So, this research was conducted to assess the effects of additive intercropping of quinoa andpotato (Solanum tubersum L.), and the methods of weeds control on yield and yield components of quinoa var. Titicaca in Jiroft and Kahnooj regions.

This study was carried out as split plot based on a randomized complete block design (RCBD) with four replications at Jiroft and Kahnooj regions. Therefore, weeds control treatments including control (no-hoeing), manual weeding (twice within 30 days after planting) and paraquat herbicide (3 days after planting of quinoa) were arranged in the main plots, while additive intercropping patterns at five levels (Q:P in the levels of 5:5, 10:5, 15:5, 20:5 and 30:5 plants per m-2), quinoa sole cropping (30 plants per m-2) and potato sole cropping (5 plants per m-2) were located in sub-plots. The effects of quinoa and potato intercropping on plant height, leaves number per plant, leaf area, flowering time, spike maturity and quinoa harvest time, average of grain weight per plant, grain yield and density of weeds as well as potato tuber yield were measured at both regions. Data were analyzed as combined analysis of variance (ANOVA) using SAS ver. 9.2. Means were compared using the least significant difference (LSD) at the 5% level (P = 0.05).

The results showed that the effects of quinoa and potato intercropping had significant effects on some characteristics of quinoa including leaves number per plant, leaf area, average of grain weight per plant, grain yield of quinoa, tuber yield of potato and density of weeds. However, intercropping had no effect on some characteristics of quinoa such as plant height, flowering time, spike maturity and quinoa harvest time. Based on the results the highest (19 g per plant) and lowest (13.9 g per plant) average of grain weight per plant were obtained in 20:5 and 5:5 plants per m-2 treatments, respectively. Whereas, the highest grain yield (4957 and 4863 kg.ha-1) were obtained in sole quinoa and 30:5 plants per m-2 treatments, respectively. The studied growth characteristics and grain rate per plant in Kahnooj were greater than those in Jiroft. Total land equivalent ratio (LER) index increased with increasing quinoa density in intercropping. The highest total LER was obtained in 30:5 plants per m-2 treatment in Kahnooj region. Moreover, the effect of manual weeding of weeds on the studied properties were more than that of the application of paraquat herbicide. The results also showed that the intercropping of quinoa and potato led to decreases in density of weeds at both flowering and before harvesting times. So that, the lowest density of weeds was related to the intercropping of quinoa and potato with densities of 20:5 and 30:5 plants per m-2 treatments. Whereas the highest rate of density of weeds were related to the sole cropping of quinoa and potato treatments, respectively. Moreover, the results showed that intercropping resulted in greater tuber yield of potato, so that the highest potato tuber yield was obtained in 30:5 treatments.

Based on the results, although the highest average grains per plantwas obtained in the intercropping of 20:5 treatment, the yield of quinoa decreased with the intercropping of quinoa and potato compared with the quinoa sole cropping. Also, the additive intercropping led to decrease in the density of weeds. Although, it seems that for quinoa cropping the climate of Kahnooj is more suitable than Jiroft, the intercropping of potato and quinoa is suitable for Kahnooj and Jiroft regions.

Cumin (Cuminum cyminum L.) is one of the most important domestic medicinal plants in the country. Currently Iran is one of the most important producers of cumin. Features such as short growing season, low water requirement, lack of interference with other crops, high economic justification for other crops and exportability, make this plant a special place in the pattern of cultivated area This plant has a special place in the cultivation pattern of arid and semi-arid regions, including Khorasan. Given that cumin is a delicate plant with low weed competitiveness and on the other hand because it leaves cover the ground as much as possible, it provides a suitable environment for weed growth and development. Although cumin growers are currently struggling with weeding the fields mechanically, this method is costly and damages to the cushion bushes, identifying the herbicide of choice for combating weeds. The weeds of this plant will be a great step towards reducing the cost of its production. Therefore, the purpose of this study was to evaluate the chemical control of weeds and to evaluate the cumin tolerance to herbicides and to select herbicides for this important medicinal plant.

In order to evaluate the efficacy of herbicides from cell division inhibitor and photosystem II inhibitor groups, an experiment was conducted as a randomized complete block design with 6 treatments and 3 replications in Agricultural Research Farm at University of Birjand 2017. In this research herbicides from cell division inhibitors group including trifluralin pre-plant incorporated (2 L.ha-1), pendimethalin pre-plant incorporated (3 L.ha-1), pendimethalin preemergence (3 L.ha-1) as well as herbicides from photosystem II inhibitors group including prometryn preemergence (2 Kg.h-1), metribuzin preemergence (1 Kg.h-1) and a weeding treatment was also added. The measured traits for weeds included: height, density, dry weight, leaf area and for cumin included: seed yield and biological yield.

According to the results of analysis of variance, herbicide treatments had a significant effect on density, height, dry weight and leaf area at different stages of weed sampling. Comparison of mean data on total weed density showed that after weeding treatment, application of pendimethalin preemergence caused an almost 100% reduction in total weed density, which was not statistically significantly different from pre-plant incorporated trifluralin. Concerning weed height, the results showed a significant decrease in the effect of herbicides on weed height. Comparison of means showed that preemergence and pre-plant pendimethalin had a great impact on weed leaf area reduction. Experimental treatments had a significant effect on weed dry weight. Results showed that pendimethalin herbicide had the greatest percentage of reduction in total weed dry weight after weeding treatment. The results of visual assessment also indicated the greater impact of cell division inhibitor herbicides on weed control at all three sampling stages. Preemergence pendimethalin had the greatest efficiency in weed control, whereas metribuzin and prometryn had the least efficiency in this regard. Moreover, the results of visual assessment of herbicide effects on cumin showed that pendimaline had no significant effects on cumin either in pre-plant or pre-emergence applications, probably due to the rapid metabolism of this herbicide in the plant and its low mobility in the soil. The greatest damage to cumin was related to metribuzin. The results showed that the greatest seed yield was related to full-season weeding treatment, followed by pendimethalin herbicide application which caused a 204% increase in the crop seed yield and the lowest seed yield was related to metribuzin with 63% reduction in crop seed yield. It seems that due to relatively long survival of metribuzin in the soil (30-60 days) and the high susceptibility of cumin to this herbicide, it caused severe damage to the crop.

All herbicides applied in this study showed an acceptable level of control over weeds in terms of percentage of density reduction, dry weight, height, and leaf area of ​​weeds. Pendimethalin herbicide after weeding all season had the highest percentage of grain yield and biological yield enhancement, while the least performance was related to metribuzin. According to the results of the visual assessment, the greatest and least impacts of herbicides on weeds was occurred with pendimethalin and metribuzin, respectively. In general, according to the results of this study, pendimethalin herbicide can be effective in controlling weeds and enhancing the yield of cumin because of its greater inhibitory effect on weeds as well as its safety for cumin.

Species distribution models (SDMs) are a tool for the management of wildlife including the roe deer, Capreolus capreolus, as an elusive and national protected herbivore in Iran. Habitat suitability modeling can be one of the most important steps to protect this species. This study was carried out to evaluate the potential distribution of the roe deer in the north and northwest of Iran and to identify the important habitat patches for this species. The habitat suitability modeling was applied 95 presence points and nine environmental variables by MaxEnt®. Thereafter, we focused on the extraction of important habitat patches based on presence points. The land cover, as the most important variable on the habitat suitability model of roe deer and its highest probability presence, is classified as the high and moderate densities in the forest. Habitat patches covered an area of about 4467.81 km2 (i.e., 6.04%of the study area). The largest habitat patch, covering an area about 4022 km2, created a continuous patch in the east of the study area. There were several inter-connected small patches in the most western part of the study area in Arasbaran forests. Actually, Habitat patches should be taken into consideration in the conservation of the roe deer.

In order to evaluate the potential of citogate and turnip vegetable oil in increasing the performance of barnyardgrass (Echinochloa crus-galli) control by colthodim and haloxyfop-r-methyl ester herbicides, two greenhouse experiments were carried out in the Research Greenhouse of the Faculty of Agriculture, Birjand, Iran, in 2016; this study was based on a factorial arrangement as a completely randomized design with three replications. Treatments in each experiment included herbicide concentrations at seven levels (0, 6.25, 12.5, 25, 50, 75, and 100% of the recommended dose) and additives were applied at three levels (turnip oil, citogate, and without additives). The application of additives with colthodim herbicide on barnyardgrass (based on the shoot dry weight) led to 4.5% and 5.4% decreases in ED50 in the presence of turnip oil and citogate, respectively. Based on the root dry weight, ED50 was reduced to 22.9% and 21.6% in the presence of turnip oil and citogate, respectively. The results of the use of additives with Haloxyfop-r-methyl ester also showed a similar trend. However, the increase in the efficiency of Haloxyfop-r-methyl ester was higher than that of colthodim herbicide. The Haloxyfop-r-methyl ester ED50 values for the shoot dry weight of barnyardgrass were reduced by 14% and 16.3% in the presence of turnip oil and citogate, respectively. The Haloxyfop-r-methyl ester ED50 values for the root dry weight in the presence of turnip oil and citogate were 10 and 7 times higher than those in the treatments without additives, respectively. According to the results of this study, application of appropriate additives may lead to decrease in the extent of herbicide contamination of soil and water resources.

In this paper we suggest a procedure for testing reversibilityof time series. Our approach is based on a necessary and sufficientcondition for time reversibility of linear models. An attractive featureof the procedure is that in converse with other approaches it doesn’trequire important assumptions, especially existence of moments of orderhigher than two. Our simulation confirms the procedure and some empirical examples are given.