مجله تولید و فرآوری محصولات زراعی و باغی
سال دوازدهم شماره 3 (پیاپی 95، پاییز 1401)

In order to investigate the effect of quinoa seed inoculation on photosynthesis rate, yield and competitive ability with weeds, an experiment was conducted as split-plot based on a randomized complete block design with three replications at experimental farm of School of Agriculture, Shiraz University, Shiraz, Iran during 2020 growing season. Treatments were three levels of weed management as main-plot (weedy, weed-free and weeding) and five levels of seeds inoculation with biofertilizers (humic acid, bioumic, seaumic, organic herbicide, and no biofertilizers) as subplots. The results showed that the highest rate of photosynthesis in all weed management levels was achieved in the presence of seeds inoculated with seaumic biofertilizer. The highest grain yield (259.63 g/m2) and grain yield components (1000-seed weight, number of seeds per panicle, and number of panicles per plant) and harvest index (48.73%) were also obtained in weed-free plots when seeds were inoculated with seaumic biofertilizer. Leaf area index and dry weight of the main weed species (wheat) was significantly reduced in inoculation of seeds with biofertilizers compared to the no biofertiliuzer condition. The highest crop’s competitive ability was achieved when the seeds were inoculated with seaumic treatment. The quinoa’s competitive ability was increased by 2.8 times and 94.11% at weedy and weed-free treatments, respectively, compared with control in seed inoculation with seaumic treatment. Thus, our finding suggests that seed inoculation with biofertilizers, especially seaumic treatment is an effective strategy that can be used to enhance germination rate, growth, yield and weed competitive ability in quinoa.

Drought is one of the most important environmental factors affecting plant growth. The double haploid method is one of the most common breeding methods in wheat. Using old cultivars in cross-breeding programs can be effective for restoring genes lost during evolution. In this study, in order to evaluate the genetic diversity and to select the drought-tolerant introgression wheat lines, 151 double haploid (DH) lines (derived from cross of old and modern cultivars) were evaluated under two moisture conditions (non-stress and drought-stress) in field. Considerable genetic variation was observed among DH lines for most of the traits indicating that selection for these traits can be effective to develop lines with higher performance or for specific purposes. The effect of drought stress was significant for most of the traits. For example, drought stress reduced grain yield by 40%. Comparison of old and new parent genotypes showed that the new parent was earlier in maturity, dwarf and had higher grain yield, yield components and harvest index. Transgressive segregation was observed for most of the traits indicating the possibility of selection for superior lines. In both moisture condition, plant height had the highest narrow sense heritability (46%) and leaf relative water content had the lowest one (12%). Grain yield had negative correlation with day to flowering indicating that selection for earliness can improve drought tolerance. According to the results of tolerance indices and biplot of principle component analysis, superior lines were identified. For example superior lines for grain yield, early flowering and higher harvest index were recognized for future studies.

In order to investigate the effect of salinity on the physiology of two cultivars of green and orange bell peppers, an experiment was conducted at the Isfahan University of Technology, Isfahan, Iran in 2019. The experiment was a factorial experiment in a completely randomized design in the greenhouse, in which treatments included four salinity levels (irrigation with normal water, irrigation with saline 1.5, 4.5, and 6.5 dS/m). Increasing the salinity level increased the activity of the ascorbate peroxidase enzyme in orange bell pepper. The highest amount of activity of this enzyme was achieved in orange cultivar when grown in the presence of 6.5 dS/m saline water. Green bell peppers had a higher starch content than orange bell peppers at all salinity levels. Also, with increasing salinity, the K concentration of roots and shoots and Na concentration of shoots increased compared to the normal water irrigation condition. An increasing trend in proline and phenol concentrations was observed with increasing salinity level. Also, increasing salinity level significantly reduced transpiration, stomatal conductance and CO2 concentration in the sub-stomatal space. With increasing salinity level, the abscisic acid and carotenoids concentrations in the leaves increased. In general, salinity led to adverse effects on an array of the examined physiological attributes of both genotypes, though, orange cultivar seemed to be more tolerant to the saline water, compared to the green pepper.

The aim of this study was to evaluate the toxicity of black cumin (Nigella sativa) extract on germination and growth of flixweed (Descurainia Sophia) seedlings grown in wheat (Triticum aestivum) fields, isolation and identification of important bioactive compounds of its aqueous extract. Two factorial experiments were conducted in a completely randomized design with three replications. In each experiment, the treatments included two levels of black cumin aqueous extract (root and shoot) and four concentrations of the extract (0, 50, 100 and 150 mL/L). The results showed that the highest plumule length belonged to wheat treated with 50 mL/L of black cumin root extract and the lowest to flixweed treated with 150 mL/L of black cumin shoot extract. With increasing the concentration of black cumin extract, the amount of seedling vigor index decreased significantly. In addition, the inhibitory effect of black cumin shoot extract on seedling dry weight and germination percentage was higher than the root extract. In root and shoot extract of black cumin, flavonoid compounds (12.9% and 16.7%, respectively), phenol (19.4% and 26.7%, respectively), terpenoids (14.5% and 19.2%, respectively) were observed. Inhibition of germination and seedling growth of flixweed was attributed to important inhibitory compounds including polyphenols, flavonoids such as tricarboxylic acids, alkaloid compounds such as magnetofluorine, myristicin, norargemonin and niglamine. In general, it is concluded that black cumin extract with strong toxicity to weeds can help the development of biocides.

Drought is one of the most common stresses experienced by plants and limits plant growth throughout the world, especially in the arid and semi-arid areas. In this research, the effect of vermicompost on olive (Olea europaea L. cv. Zard) morpho-physiological traits and drought tolerance was investigated. A factorial experiment was conducted in completely randomized design with two factors, including vermicompost application at four levels (0, 12.5%, 25% and 50%) and drought stress at two levels (full irrigation and non-irrigation) and 4 replications in the research greenhouse of the Department of Horticulture, Isfahan University of Technology, Isfahan, Iran. Drought stress decreased relative leaf number, but addition of vermicompost increased it. Drought stress decreased the relative water content, chlorophyll a, b, carotenoids, and root P concentrations and increased leaf and root Na concentration, and application of vermicompost significantly decreased Na concentration of the roots. In spite of positive effects of all vermicompost levels on growth parameters and drought tolerance, the highest number of leaves, chlorophyll a, b and carotenoid concentrations and drought tolerance was observed in plants fertilized with 25% vermicompost. The results showed that applying 25% vermicompost to the soil led to improvements in an array of plant growth parameters and K and P concentrations of the roots, due presumably to an improvement in physical and chemical properties of the medium.

Adverse environmental conditions cause stress in plants, and some plant growth regulators (PGR’s) improve plant tolerance to these undesirable conditions. In order to study the effect of gibberellin, cytokinin and cycocle on some physiological traits of two wheat cultivars under different irrigation regimes, a study was conducted as a split-split plot experiment based on a randomized complete block design with three replications at the Agricultural Research Station of Kurdistan University, Sanandaj, Iran in 2016. Irrigation at four levels: rainfed, irrigation at booting stage, irrigation at booting + flowering and irrigation at booting + flowering + grain filling stages as the main plots, two wheat cultivars (Sirvan and Homa) as sub-plots and levels of plant growth regulators foliar application including control (no-PGR), gibberellin (100 µm), cytokinin (100 µm) and cycocel (3 g l-1) at the wheat stem elongation and grain filling stages as the sub-sub plots were examined. The results showed that soluble carbohydrates concentration was higher in rainfed conditions, compared to the other levels of irrigation. Relative water content, rate of water loss and maximum quantum yield of photosystem II (Fv/Fm) increased due to irrigation, relative to the rainfed condition. A higher chlorophyll a and total chlorophyll concentration was observed with cytokinin spray in the presence of the three irrigation treatments. The results also indicate that, at the stem elongation and grain filling stages, foliar application of gibberellin reduced the rate of leaf water loss. Application of cytokinin and cycocel increased the concent of carotenoids, application of gibberellin and cycocel increased the Fv/Fm and the use of all three PGR’s increased soluble carbohydrates concentration compared to the no-PGR condition. The highest grain yield was obtained with cytokinin and cycocel spray at the wheat stem elongation and with the application of cycocel at grain filling stages under the condition of irrigation at booting + flowering + grain filling stages. Homa cultivar produced a higher grain yield compared to Sirvan. It may be concluded that the application of cytokinin and cycocel is beneficial to some physiological attributes and hence increasing the grain yield of wheat.

To evaluate quantitative and qualitative traits as well as thrips resistance of onion genotypes, an experiment was conducted at Behbahan Agricultural Research Station, Behbahan, Khuzestan, Iran from 2013 to 2015. The experiment was a split plot based on a randomized complete block design with three replications. Pesticide-treated and pesticide-free plots were considered as sub plots and ten onion genotypes (Behbahan, Padook, Ramhormoz, Iranshahr, Borazjan, Dorcheh Esfahan, and Kamerei Khomain landraces, Primavera and Texas early grano cultivars and improved population of Behbahan onion) were considered as main plots. The seeds were sown in nursery bed in early October and the seedlings were transplanted into the field at 2-3 leaf stage in mid-November. The bulbs were harvested when 50-80% of foliage top had fallen and collapsed. Among different thrips species the Thrips tabaci Lindeman was the predominant in the experimental field. To control the thrips, the pesticide was applied 4 and 3 times in the first and second years of experiment, respectively. Leaf length, total and marketable yield, mean bulb weight and bulb dry matter percentage were significantly higher in the pesticide-treated plots than in the pesticide-free plots. However, thrips population was significantly lower   in the pesticide-treated plots than the pesticide-free ones. Also, the spraying had not significant effect on the number of leaves. Due to the lack of significant differences between total and marketable yield of Ramhormoz genotype in the pesticide-treated plots and pesticide-free plots, it can be concluded that this genotype is capable of resisting thrips, at least in part, compared to the other genotypes. While Texas early grano cultivar produced the highest yield in the pesticide-treated plots, in the pesticide-free plots the highest yield belonged to Primavera cultivar. According to the results obtained, it can be concluded that the Texas early grano and Primavera cultivars are suitable for cultivation in the presence and absence of anti-thrips pesticides, respectively.

In order to investigate the effect of salinity and cadmium (Cd) on yield, chlorophyll content and antioxidant activity of Kochia plant, a factorial experiment in a completely randomized design with three replications was conducted under greenhouse conditions. The experimental treatments included five Cd levels (0, 5, 30, 60 and 90 mg Cd kg-1 soil as cadmium sulphate) and three salinity levels (0, 2.5 and 5 g kg-1 soil as NaCl equal to electrical conductivity (EC) 0.65, 9.4, and 18 dS m-1, respectively). The results showed that mean shoot fresh and dry weight, root weight, and plant height at 5 g NaCl Kg-1, decreased significantly by 22, 24, 23, and 15 %; and at 90 mg Cd Kg-1 soil decreased by 52, 67, 45, and 41%, respectively. The greatest reduction in shoot fresh and dry weight, root dry weight and plant height observed at 5 g NaCl Kg-1 + 90 mg Cd Kg-1 levels. The highest total chlorophyll content observed at control (with no salinity and Cd) and 5 g kg-1 salinity + 5 mg Cd kg-1. With addition of NaCl, the harmful effect of Cd on chlorophyll content of the plant decreased. Salinity and Cd levels had a different effects on antioxidant activity of Koshia plant. However, at higher Cd levels (60 and 90 mg Cd kg-1), with increasing of salinity levels, no significant differences was observed in peroxidase and superoxide dismutase activity. In general, the change in the activity pattern of the plant antioxidant system, especially catalase and superoxide dismutase enzymes under high stress conditions showed that Kochia plant can withstand stress conditions via activating its antioxidant system.

In order to evaluate the growth indices of sugarcane in different irrigation systems, weed control treatments and correlative associations with quantitative and qualitative traits of sugarcane, an experiment was conducted as split plot based on randomized complete block design (RCBD) with three replications in 2020 at Sugarcane Development Research and Training Institute of Khuzestan, Ahwaz, Iran. The five irrigation systems were surface irrigation, subsurface irrigation with a flow rate of 2.3 L/hour, subsurface irrigation with a flow rate of 3.6 L/hour, sprinkler irrigation and furrow or conventional irrigation as the main plot and weed control treatments were (weed interference (no weeds control) throughout the season (Weedy treatment), weed control in total period of season (weed free treatment) and cultivation (twice) as the subplot. The highest crop growth rate (CGR), dry matter and height were observed in sprinkler and subsurface irrigation with a flow rate of 3.6 L/hour and the lowest in furrow irrigation. Growing degree day (GDD) required to reach 50% of dry matter were determined for sprinkler irrigation (1894), subsurface irrigation with flow rate of 3.6 L/hour (1762), subsurface irrigation with flow rate of 2.3 L/hour (1538), surface irrigation (1494) and furrow irrigation (1474 degrees of growth day). Also, growth indices in weedy treatment was lower than the both treatments weed free and cultivation. Correlation analyses indicated that sugarcane quality traits were not closely associated with growth indices and sugarcane quantitative traits. However, a positive correlation was observed between quantitative traits of sugarcane such as height, internode length, number of internodes, cane yield, sugar yield, dry matter and crop growth rate and a negative correlation was observed between cane yield with stem diameter and weeds biomass. According to the results, both systems of sprinkler irrigation and subsurface irrigation with a flow rate of 3.6 L/hour seem to be suitable for sugarcane production in Khuzestan in the first ratoon.

This research was conducted at the research field of West-Azerbaijan (Saatloo station, 45° 10′ 53˝ E/ 37° 44′ 18˝ N and 1338 m above sea level), located 25 km from Urmia city (Iran) during 2019-2020 cropping seasons, as a factorial layout based on randomized complete block design with three replications. The first factor was irrigation regime at three levels (supplying 100, 75 and 50% of net irrigation requirement) and the second factor was planting method of wheat at four levels (plot planting, planting three lines on the ridges (ridges width=30 cm), planting four lines on the ridges (ridges width=45 cm) and planting five lines on the ridges (ridges width=60 cm)). The results showed that the highest grain-yield’s water use efficiency (1.38 kg m-3), dry mass water use efficiency (3.22 kg m-3), carotenoid content (1.02 mg g-1 fresh leaf weight), chlorophyll ratio a to b (3.52) and grain protein percentage (9.89%) were obtained from supplying of 50% of net irrigation water requirement. But the maximum grain yield (7093.30 kg ha-1) and dry mass (15282 kg ha-1), chlorophyll a (1.59 mg g-1 fresh leaf weight), chlorophyll b (0.56 mg/g fresh leaf weight), total chlorophyll a and b (2.15 mg g-1 fresh leaf weight) and protein yield (806.85 kg ha-1) were obtained from supplying of 100% of net irrigation water requirement. Planting three lines on the ridge increased grain yield, dry mass, flag leaf area, grain-yield’s water use efficiency, dry mass water use efficiency, carotenoid content, photosynthetic pigments and protein yield by 29, 33, 31, 29, 33, 38, 7 and 35%, respectively. In general, based on our findings in this study, planting the wheat on the ridge was superior to the traditional method in terms of grain yield and water use efficiency. Also, reducing irrigation water consumption by up to 50% of net requirement did not cause a significant difference in grain yield and dry mass. Therefore, in order to save water consumption and improve water use efficiency, supplying of 50% of net irrigation water requirement along with planting three lines on the ridge is recommended.