فصلنامه پژوهش های تولید گیاهی
سال سی‌ام شماره 4 (زمستان 1402)

Research Iris Pseudacorus is a perennial herbaceous plant with yellow flowers belonging to the Iridaceae family which is used as an ornamental plant. The light changes led to different morphogenetic and photosynthetic responses in some ornamental plants. LED lights could improve the growth and physiological development of plantlets and affects the morphogenesis and secondary metabolite production of plants. The goal of the present study was to investigate the effects of the LED lights on the growth, development, physiological and morphological indices of the Iris Pseudacorus.Research This experiment was conducted with a factorial arrangement based on a completely randomized design with two factors of light intensity (1500 and 3000 lux) and light quality 100% white (control), 100% red light, 100% blue light, 20% red + 80% blue, 40% red + 60% blue, 60% red + 40% blue and 80% red + 20% Blue} by using 4 replications The measured morphological and physiological traits were leaf number and length, leaf area, fresh weight, percentage of regeneration, Survival rate, root number and length, total phenol and flavonoid, chlorophyll a, b and total and carotenoid. Analysis of variance results showed that the interaction of different light intensities and qualities on the evaluated indices was not significant. It also indicated that the light intensity treatment had a significant effect on leaf number, leaf length and leaf area and total phenol content (P<0.01) and fresh weight, survival percentage, regeneration percentage, total flavonoids content, chlorophyll a, chlorophyll b, total chlorophyll, and carotenoids (P<0.05). Also, light quality treatment significantly affected total phenols and flavonoid content (P<0.01). A comparison of the mean for the effect of different light intensities indicated that the highest leaf number, leaf length, leaf area, survival percentage, regeneration percentage, and also the highest fresh weight, total phenol, total flavonoids, chlorophyll a, chlorophyll b, total chlorophyll was observed in 3000 lux light intensity. Also, a comparison of the mean data obtained from the effect of different light qualities showed that the highest amount of total phenol (mg GAE / g FW038.3) and total flavonoids (GAE / g FW 8.796 mg) was observed in 100% blue light treatment. According to the findings of the present study, it can be concluded that light intensity compared to different light qualities has a more significant influence on morphological and physiological parameters of in vitro plantlets of the Yellow Flag. The results also indicated that with increasing light intensity from 1500 to 3000 lux, morphological and physiological indices of Yellow Flag plantlets were significantly enhanced. It indicates that increasing light intensity in mass and commercial production of this plant under in vitro conditions would be effective.

Post-harvest waste of strawberry fruit is high due to its high sensitivity to fungal agents and has caused a very short development of this valuable and useful fruit. On the other hand, the use of synthetic antifungal chemical compounds to increase the shelf life of this fruit has caused many concerns. For this reason, it is necessary to use safe methods to control spoilage and maintain the quality of strawberry fruit during storage. Today, the use of natural antimicrobial essential oils in oral coatings has attracted the attention of consumers. The essential oil of thyme has a great antibacterial, antifungal and antioxidant effect.

This study was performed as a factorial experiment in a completely randomized design with three replications in the research greenhouse of the Faculty of Agriculture, Lorestan University. The first factor is the type of material with different concentrations in five levels including 0, 0.3%, 0.6%, the combination of chitosan with thymol 0.3 % and 0.6 % and the second factor is the storage time in four levels including 0, 9, 18, It was 27 days after storage. Harvested fruits at 4 ° C with a relative humidity of 90±5 and parameters such as weight loss, pH, fruit firmness, acidity (TA), soluble solids (TSS) and taste index, vitamin C, Phenol and flavonoids, fruit shelf life (number of days) during storage, were studied.

The results of analysis of variance showed that the effect of treatment type and storage time on all studied traits was significant at the level of one percent probability. Fruits treated with chitosan and thymol 0.3% and 0.6% had higher tissue firmness, vitamin C, taste index, phenolic substances and soluble solids content and better durability than the control. In all four measurement times, the highest content of phenol, vitamin C and tissue stiffness was related to chitosan and thymol treatment of 0.3 and 0.6 % and the lowest was related to the control. Fruit tissue firmness gradually decreased during storage, but this trend was observed at a significantly slower rate in treated fruits.

Considering the increase of 7 and 9 days after harvest of combined treatment of chitosan and thymol 0.3 % and 0.6 % in comparison with other treatments and control, therefore, pre-harvest application of chitosan and application of edible coating thymol can be recommended as a safe and low cost strategy to increase the postharvest life of strawberry cultivar 'Parus'.

Cotton yield and most important traits in terms of economic and breeding values are polygenic traits, and direct selection for them has not been very successful. This study was conducted to identify the relationships between yield and its related traits and to determine the most important traits affecting cotton lint-yield.

an experiment including nine genotypes with two commercial varieties of Fars province (Bakhtegan and Golestan) as controls, in a randomized complete blocks design with four replications, was carried out at Darab Agricultural Research Station during two years of 2017 and 2018. In this study, the traits of plant height, monopodial length, monopodial number, sympodial length, sympodial number, number of boll per plant, boll weight, earliness percentage and lint-yield were investigated.

The combined variance analysis results for the studied traits showed that the genotype had a significant effect on all traits except for the monopodial length and the sympodial number at the 1% probability level. The comparison of genotype means showed that the genotypes A-NB414 and A-NBK had the highest lint-yield of 5445 and 5154 kg/ha, respectively. The lint-yield of these two genotypes were significantly different from those of the other genotypes. The genotypes A-NB414 and A-NBK also had higher values for plant height, sympodial number, number of boll per plant, and earliness percentage than the other genotypes. The phenotype correlation analysis showed a significant positive correlation between lint-yield and number of boll per plant (r= 0.80**), boll weight (r= 0.36**), and plant height (r= 0.60**) at the 1% probability level. The stepwise regression analysis results showed that the traits of number of boll per plant, boll weight, plant height, and sympodial length had the most significant effects on cotton lint-yield (R2=0.77). According to the results of the path analysis, the number of boll per plant had the most direct effect on lint-yield (P=0.78). The indirect effect of plant height on lint-yield was exerted through the number of boll per plant. The lint-yield of these two genotypes was significantly different from other genotypes. A-NB414 and A-NBK genotypes were superior to other genotypes in plant height, sympodial number, number of boll per plant, and earliness percentage. The phenotypic correlation showed a high and significant correlation at 1 % level of probability respectively between the lint-yield and the number of boll per plant (r= 0.80**), boll weight (r= 0.36**) and plant height (r= 0.60**). The results of step-by-step regression analysis showed that the traits of boll number, boll weight, plant height and sympodial length explain the most lint-yield changes (R2 = 77.59). According to the results of the path analysis, the most direct effect on the lint-yield trait was related to the number of boll per plant (P=0.78). The most indirect effect of plant height was exerted on lint-yield through the number of boll per plant.

Considering the very high correlation between the lint-yield and the number of boll per plant, it can be concluded that the number of boll per plant is the main factor causing genotype differences in lint-yield. Since boll weight, number of boll per plant and plant height have the largest direct effects on cotton lint-yield, these traits can be used as selection criteria. Additionally, since the number of boll per plant has the most direct and indirect effect on lint-yield, it can be used to increase lint-yield in breeding programs.

Pollen flow in anemophilous plants is a dynamic process. This controlled by wind speed, turbulence direction and depends on, plantation map, rate of air humidity, male genotype and female cultivar biological characteristics. The aims of this research were to survey and analysis pollen dispersal model in distance from few male genotypes within a block of Shahpasand and Akbari pistachio cultivars.

The lams coated with thin layer of Vaseline gel were installed on piece of wood tied on top of wooden bars. The bars had a distance of 7 m to each other as distance of female trees. . The lams were installed horizontally and vertically on bars which had planted beside female tress from a distance of 8 to 64m in Shahpasand and 80 m in Akbari plot. Every lam was installed on woody bar from 8 am to 8 am of next day and number of pollen was counted on horizontal and vertical lam via a light microscope. Data were analyzed using RCD and regression analysis, as Y is accounted as pollen intensity and X as distance to pollinizer.

Results indicated the pollen intensity was declined after 35 m distance from male genotypes. Further, fruit set also indicated a decreasing trend as distance had been increased from male genotypes. However, the intensity of pollen was differed on different day. This was due to some differences appeared by wind speed and direction. The best wind speed on 2 M height from the ground was 10 km/h equal to 2.7 m/s. On days when the speed of winds was raised to more than 30 km there were no traces of pollens dispersal on lams and dusts were replaced. The maximum intensity of pollen in Akbari plot was found in distance between 20 to 30 m from male trees. The recent results indicated a sinusoidal model. There was no found significant differences in fruit set percentage by open pollination and by controlled pollination by hand in Shahpasnand plot. Even though the intensity of pollen was reduced in 40 m distance from male tree but this condition had no effect on rate of fruit set percentage in Shahpasand plot.

Within this research it was cleared that pollen intensity in both plots of Shahpasand and Akbari female trees was influenced by wind speed, wind direction and frequency of male trees. Intensity of pollen was reduced by 40 m from pollen source in both plots of Shahpasanand and Akbari. There was no reduction in fruit set at Shahpasand by 60 m distance from the male tree. It is suggested plantation of few male tree in the row for 3 of 4 rows of female pistachio trees would be more beneficial for orchardist

Background and objectivesSoybean is considered one of the most important oil and protein plants in Iran and the world. Considering the importance of soybean yield and identifying traits effective in increasing it, this research was conducted with the aim of investigating the relationship between seed yield and agronomic and physiological traits of soybean and determining the traits that have a greater effect on seed yield under normal and accelerated aging conditions.Materials and methodsThe present experiment was conducted in the research farm of the Faculty of Agriculture of Shahrood University of Technology during 2017-2018 and 2019-2020, in a factorial experiment in the form of randomized complete blocks in three replications on Katol variety. The treatments included accelerated aging in two levels (normal seeds and aged seeds) and seaweed extract in three levels (control, pre-treatment and foliar spraying). The seeds used were obtained from the research center for agriculture and natural resources of Mazandaran and the seeds were harvested in the same year and until the time of testing, they were kept in a controlled warehouse with a cooling system at a temperature range of 14 to 17°C and a relative humidity of 30 to 40%. In order to apply aging, the seeds were placed for 72 hours at a temperature of 41°C and a relative humidity of 95%.ResultsThe results showed that in plants obtained from normal seeds, 84.81% of the changes in seed yield are justified by the number of pod per plant, the number of seed per pod and the 100 seed weight. In these plants, the 100 seed weight and then the number of pods per plant had the most direct and positive effect. The most direct and positive effect was attributed to the 100 seed weight, followed by the number of pods per plant. The trait of the number of seed per pod affected the seed yield both directly and indirectly through the effect on the 100 seed weight. Causality analysis in the plants obtained from aged seeds showed that the characteristics of final emergence percentage, membrane stability index, leaf area index, anthocyanin, hydrogen peroxide, superoxide radical, number of pods per plant and 100 seed weight were entered into the model as main variables and 91.33% of the changes are explained by these eight traits. Seed pre-treatment with seaweed extract increased seed yield by increasing the percentage of final emergence of the field, the 100 seed weight and the amount of glutathione in the leaves of the plant. Foliar spraying of seaweed extract caused a significant increase in seed yield through increasing the weight of 100 seed weight and membrane stability index.Conclusion The characteristics of 100 seed weight and number of pods per plant in plants obtained from normal and aged soybean seeds can be considered as selection criteria for improving and improving yield due to their direct and increasing effect on seed yield.

Salinity is one of the abiotic stress factors that causes great damage to the production of agricultural products around the world. Various strategies have been adopted to reduce the negative effect of salinity on plants and to improve the growth and development of plants under salinity stress conditions. In the present study, the effect of silicon foliar application on decreasing the effects of salinity stress and its related physiological mechanisms in hot pepper plants has been investigated. The research was conducted as a factorial experiment based on completely randomized design with three replications in the greenhouse of Ilam University. The treatments tested in this research included three levels of salinity stress (control, 75 and 150 mM NaCl) and four levels of silicon (control, 0.5, 1 and 2 mM). In the stage of four expanded leaves, silicon treatment was applied as a foliar spray in the mentioned concentrations until the surface of the leaves was completely wet, and it was repeated two more times after one month. Salinity treatment was done by preparing NaCl solution and i the plants with fertilizer solution every three days. The treatments were continued until fruiting and complete fruit harvesting. In the final results obtained from this research, it was found that salinity caused a significant decrease in growth and performance parameters (root and shoot dry weight, plant height, number of fruits per plant and crop yield) as well as a decrease in relative water content and chlorophyll and caused increase in the content of proline, malondialdehyde and ion leakage in pepper plants. The results showed that the application of silicon reduced the effects of salinity stress on pepper plants. The highest total yield was obtained in 1 and 2 mM silicon application under non-saline irrigation. At all salinity levels, the application of silicon increased the growth and yield of pepper plants. These results were related to the increase in relative water content and chlorophyll, and decreases in proline, malondialdehyde accumulaion and electrolyte leakage. In general, the results of this research indicated that the application of silicon, especially in concentrations of 1 and 2 mM, improved the growth and performance of hot pepper plants under stress and non-stress conditions. The exogenous application of silicon alleviated the negative effects of salinity on the plant by increasing the amount of chlorophyll and relative water content and decrease proline and malondialdehyde. Although the application of silicon in non-saline conditions had positive effects on plant growth and performance, it was more effective in saline conditions. Therefore, silicon foliar spraying is recommended to decrease the effects of salinity on the growth and performance of hot pepper plants.

After potato, watermelon is the most important vegetable that cultivated in Iran. Irrigation is necessary for watermelon cultivation due to its high growth rate, short growth period and high fruit water content (90-92%). In addition high evaporation during growth and development stages and low rainfall in arid and semi-arid area caused that cultivation of watermelon need a lot of water. To minimize drought stress effect on yield of agricultural crop in arid and semi-arid areas, cultivation of drought tolerant cultivars, deficit irrigation practice and grafting of high yielding cultivars onto tolerant rootstocks are recommended. No paper has been published about grafting and deficit irrigation for watermelon cultivation in Khuzestan province yet, therefore present research was conducted to study the effects of these factors on yield, yield components and water use efficiency of grafted watermelon (B32 cultivar) onto pumpkin ‘Cubalt and Ferro’ (Cucurbita maxima × Cucurbita moschata.) and deficit irrigation in nongrafted watermelon.

This study was carried out at Behbehan Agriculture Research Station from 2020 to 2021. The experiment was done as strip plot in randomized complete block design with nine treatments and three replications. Three irrigation regimes, full irrigation, 80% and 60% of full irrigation were considered as vertical strips. Horizontal strips included B32 cultivar grafted onto pumpkin ‘Cobult and Ferro’ rootstocks (Cucurbita maxima × Cucurbita moschata.) and nongrafted B32. Watermelon and pumpkin seeds were planted in greenhouse in 5 and 10 January respectively and watermelon seedlings were grafted onto pumpk in 4 February. Seedlings were transplanted in 24 Feb. and fruits harvested from early to mid-June. Results were analyzed by MSTATC statistical software and comparison of meanes were done using Duncan,s Multiple Range Test at 1% probability level.

Yield, mean fruit weight and water use efficiency in grafted plants were significantly higher than nongrafted plants. Yield and mean fruit weight decreased significantly due to deficit irrigation. The most yield in grafted and nongrafted plants were obtained in full irrigation. The decrease of yield in nongrafted plants applied 80% of full irrigation as compared with full irrigation was not significant. In full irrigation regime the mean yield of grafted plants were significantly higher (50%) than nongrafted plants. The yield of grafted plants applied 80% of full irrigation were higher than nongrafted plants applied full irrigation , however this difference was not significant. Water use efficiency of grafted plants was significantly higher as compared with nongrafted plants. The differences of water use efficiency in grafted plants onto Cobult and Ferro rootstocks applied full irrigation, 80 % and 60% of full irrigation were not significant. In nongrafted plants the most water use efficiency belong to applied 80% of full irrigation. The decrease of water use efficiency in plants applied full irrigation was not significant as compared with this treatment. However the decrease of water use efficiency in plants applied 60% of full irrigation was significant in comparison to plants applied 80% of full irrigation.

grafting of B32 cultivar onto Cobult and Ferro rootstocks and applied full irrigation and 80% of full irrigation were recommended in no water restriction and water shortage conditions respectively for the maximum watermelon production in Khuzestan province.

The date palm tree tolerates high temperatures, drought and salinity more than the other fruit crops that is why date palm tree is named the tree of life in the desert. A conventional date palm management practices is fruit thinning. Fruit thinning allow the remaining fruits to develop larger sizes and better qualities. Also, fruit thinning helps to overcome the alternate bearing problems. The purpose of this research to assess the effect of chemical and hand thinning on several fruit properties of date palm cv. Estameran.

This study was conducted to investigate the effect of chemical and hand thinning on fruit characteristics of ‘Estameran’ date palm as randomized complete block design with three replications in an orchard with 1.5 hectares area, located at Ferdows village in Shushtar city. Experimental treatments included T1 (control), T2 (removal of 1/3 ends of spikelets at flowering stage), T3 (removal of 1/3 ends of spikelet in Kimiri stage), T4 (removal of 1/3 number of spikelets in Kimiri stage), T5, T6 and T7 (that were chemically thinned by spraying naphthalene acetic acid (NAA) at 50, 100 and 150 mg/l concentrations at flowering stage, respectively). The fruits were harvested at tamar stage and characteristics measured included: fruit length, diameter, fresh weight, fresh and dry flash fruit, seed length, seed fresh and dry weight, fresh flash weight to seed weight ratio, fruit volume, yield per spike, TSS, pH, total sugar, reducing sugar, non- reducing sugar and fruit color attributes (L*, a*, b*, hue and chroma).

The results showed that chemical thinning with 100 mg / l NAA concentration (T6 treatment) increased significantly fresh weight (10.56 g), dry weight (9.86 g), and volume (11.03 cm3) of fruit.The highest fruit flash to seed ratio (11.47) was obtained in chemically thinning by NAA at 100 mg/l (T6).The least seed length (2.33 cm) was acquired at removal of 1/3 ends of spikelet at the flowering stage (T2) but it was not significant with T3 and T5 treatments. Chemical thinning fruit by 150 mg/l NAA concentration at the flowering stage reduced yield per spike (T7). The highest amount of non-reducing sugars was obtained in T5 (46.19%) and T6 (43.13%) treatments. The maximum amount of L* indicator was obtained in T3 (19.32) and T1 (19.09) treatments. Moreover the highest amount of a* indicator (9.08) and b* indicator (11.75) were acquired in T2. The minimum amount of hue (27.62) was obtained in control (T1) and the maximum amount of chroma (15.02) was obtained in T2 treatments.

According to the finding of this research, both hand thinning and chemical thinning improved the fruit properties. Due to the fact that chemical thinning by 100 mg/l NAA concentration at flowering stage (T6) had a more effective impact on fruit characteristics, and also the chemical thinning is less expensive than hand thinning, it can be concluded that T6 treatment is more effective and it is recommended

Lavandula angustifolia L. is a perennial and aromatic plant which belongs to Lamiaceae family. The drying process is very expensive, but if it is done correctly, it significantly increases the efficiency and components of the essential oil after harvesting. In large-scale agriculture, L. angustifolia raw materials needs a lot of space and high cost for drying process due to the large volume of material at harvest time. In this case, if it is possible to directly extract the essential oil with the desired quantity and quality from the fresh plant, the production cost will be significantly reduced from the economic point of view. The aim of the current study was to evaluate the performance and quality of essential oil of L. angustifolia in different harvesting times of fresh and dried plants.

For these goals, aerial parts of L. angustifolia in full flowering stage were collected from selected plants from a 3-year farm located in Saadatshahr city of Fars province. A Factorial experiment as a completely randomized blocks design with three replications and two factors include three different harvesting times (25th of May, 8th of August and 21st of October, 2020) and two types of plant materials (fresh and dry) was performed in the farm. The essential oils of different L. angustifolia samples were extracted by hydro-distillation using Clevenger apparatus and with three replications. The yields were calculated based on dry weight and the oils were analyzed by a combination of GC-FID and GC-MS techniques, to check for chemical variability based on British Pharmacopoeia. At the end of the experiment, data analysis was performed using SAS software (version: 9.4). The means were compared by Duncan's multi-range test.

The results of the present study demonstrated that the interaction effects of harvesting times and plant materials on the essential oil yield was not significant. However, the results of variance analysis of the main compounds identified in the L. angustifolia essential oil showed that the characteristics of linalool, borneol and camphor compounds were significant at the 1% probability level, and the characteristics of the type of plant material on the linalool and linalool acetate compounds were significant at the level of 1%. The probability of 5% was significant on the borneol and camphor compounds at the 1% probability level. The interaction effect of harvest time and type of plant material had a significant effect on the two compounds of linalool and 1,8-cineole at the 1% probability level. Mean comparison of the effect of plant materials in harvest times the main compounds identified in essential oil of L. angustifolia showed that the percentage of linalool composition in the treatment of fresh plant matter and the third harvest time was the highest with an average of 21.63% and the lowest amount in the treatment of dry plant matter and the third harvest time was observed with an average of 7.53%. Also, the highest amount of 1,8-cineole compound was obtained in the treatment of fresh plant material and in the first harvest with an average of 13.90% and the lowest amount of this compound in the treatment of fresh plant material and the second harvest with an average of 4.30%.

The findings of this study showed that due to the very valuable essential oil of L. angustifolia and the world's increasing demand for essential oil, this plant is used in the pharmaceutical, food and cosmetic industries, and according to the research on the efficiency of the L. angustifolia essential oil in different harvest times, the best harvesting time was the Spring harvesting in the full flowering stage.

Improvement of plant tolerance to adverse environmental conditions has been proven by phytohormones in various plants species. However, the crosstalks between salicylic acid and jasmonic acid hormones under drought stress conditions have not been studied. Therefore, in this study, changes in the growth rate of aerial and underground organs as well as the proline content of aerial parts and roots of R. damacena to jasmonic acid and salicylic acid during the cource of drought stress conditions at three different times point were investigated.

Clonally propagated plants sown into plastic pots were exposed to constant water shortage at 25, 50 and 100% of field capacity for 11 days. Plants under different drought stress treatment foliar spraied with jasmonic acid (50 μM) and a combination of jasmonic (50 μM) and salicylic acid (1.5 μM). The first foliar application was performed a few days before the first day of the experiment and twice after the start of the water stress at intervals of seven days. Sampling was performed on days 1, 4 and 11 and morphophysiological responses (stem height, root fresh weight, root dry weight, Ionic leakage) and biochemical (leaf proline and root proline) were measured. The experiment was performed in factorial format and in a completely randomized block.

Regardless of hormonal treatment, the measured traits such as stem height, root fresh weight, root dry weight decreased compared to the control and other traits such as leaf and root proline, ion leakage increased compared to the control in drought stressed plants. Plants grown under 25% of FC showed a 4 fold increase in proline content when exposed to JA in contrast to that of control sprayed with distilled water after 4 days. This increase in proline content in shoots and roots was similar. However, non-drought stressed plants which were exposed to JA, did not show such changes. The results show that the combination of SA and JA reduces the amount of ion leakage of leaves and the proline content of roots and shoots by half to the amount produced in plants sprayed with distilled water at 25% of FC and this amount of proline is very close to non-drought stressed plants. The results showed that the loss of fresh and dry weight of roots, which was evident in JA–received plant under 25% of FC can potentially be reversed by combination of SA and JA. This was also truth for stem height.

The drought stress mitigation of SA by reversing JA effects manifested in mitigating cell ion leakage, and increase in root fresh and dry weight. Reducing the root and shoot proline content and leaf ion leakage in plant exposed to combination of JA and SA compared to JA alone indicated a negative regulatory effect of SA on JA on modulating leaf and shoot proline content as a physiological indicator of drought tolerance.