مجله تولید و فرآوری محصولات زراعی و باغی
سال دوازدهم شماره 4 (پیاپی 96، زمستان 1401)

Lisianthus is a slow-growing flowering plant whose seed germination and growth is a challenge in the tropics. Due to the marketability of this type of cut flower, this study was performed in two experiments to investigate the effect of seaweed extract (SWE) and LED on the growth of seedlings of two cultivars of lisianthus (namely Ariana and Mariachi) and its effect on flowering as a factorial experiment in a completely randomized design. The first experiment consisted of LED treatments with blue, red, blue-red, and white light at concentrations of 125, 250, 500, 750 and 1000 ml/L of seaweed extract and control treatment (no treatment) with 8 replications. According to the results of the first experiment, the greatest leaf width and stem diameter were observed in the presence of blue light and the greatest leaf diameter was observed in the presence of red-blue combined light. In the second experiment, conducted 60 days after the second experiment, the greatest number of flower buds per plant and stem length were observed under the white light condition. Also, in Arena cultivar, concentrations of 500 and 750 ml/L of seaweed extract led to a greater number of flower buds per plant than the control treatment. Increases in morphological traits of leaf width and diameter, leaf length, and internode length were observed upon exposure to blue light and red-blue combined light in both of the experiments. Enhancements in most of the morphological traits in both experiments was observed in the presence of blue light and red-blue LED combined light. According to the results of this study, it seems that production of Arena cultivar in the presence of blue light and a concentration of 500 ml /L of seaweed extract is more feasible than the other cultivar and light and seaweed amendments.

The experiment was completed to evaluate the responses of forage yield and silage quality of dual-purpose corn hybrids to urea fertigation. For this purpose, two studies were conducted each as a split plot experiment based on a randomized complete block design with three replications at two locations in research farms of College of Agriculture, Isfahan University of Technology, Isfahan, Iran, in 2016.  Two levels of nitrogen fertigation including 150 and 200 kg ha-1 in Lavark Research Field -Najafabad city; 200 and 250 kg ha-1 in Shervedan Research Field- Flavarjan city with urea fertilizer, N= 45%, and 20 forage-grain corn hybrids were designed as main and sub plots, respectively. The results showed that the increased application of nitrogen fertilizer improved biological yield in Shervedan field and dry matter percentage and silage yield in both locations, but had no effect on the ratio of forage components including leaves, stems and ears to total forage weight. The protein concentrations of silage hybrids increased significantly as a result of increasing nitrogen application in Shervedan. Also, with increasing nitrogen fertilizer, the amount of ash in both locations increased, but insoluble fibers in neutral detergent and insoluble fibers in acidic detergent decreased. The interaction effects of nitrogen × hybrid on silage acidity was significant in Shervedan. At Shervedan field, the highest biological yield (298,000 kg/ha) and silage dry matter percentage (29.8%) were observed in AGN591 and Whichita with application of 250 kg/ha N-fertilizer. AGN756 had the highest biological yield (27,200 kg/ha) and silage dry matter percentage (28.6%) upon application of 200 kg/ha N-fertilizer in Lavark field station. It seems that in each region, by using the appropriate amount of nitrogen fertilizer and selecting high-potential yield hybrids, both acceptable quantitative and qualitative yields of corn silage can be achieved.

For identification of correlations and relations among different traits in bread wheat, 30 genotypes were investigated based on a split plot experiment in the form of randomized complete block design with three replications under normal and moisture stress conditions during the 2016-2017 crop season. The results of the analysis of variance showed that the effect of genotypes was significant for most of the studied traits. The interaction effect of drought stress and genotype was significant for all examined traits except 1000-grain weight. Genotypes c-94-3 and Heidari were recognized as the best genotypes with average grain yield of 437 and 427 g/m2, respectively, in normal conditions. Under drought conditions, genotypes cd-4 and cd-6 had the lowest grain yield with an average of 104 and 108 g/m2, respectively. Based on the results of multiple regression in field experiment, under optimal irrigation conditions, flag leaf area, spike density,  number of days to 50% flowering and spike length, (R2= 0.466) and under stress conditions, grain filling rate, grain filling period and straw yield (R2= 0.736) were considered as important traits affecting grain yield.  Path analysis of grain yield under normal conditions indicated that the flag leaf area, spike density and spike length, and under stress conditions, the grain filling rate, grain filling period and straw yield, with the greatest direct positive effect were the important and effective traits in grain yield. Based on the results of the analysis of the grain yield correlation coefficients under normal condition, the number of kernels per spike, 1000-grain weight, flag leaf area, spike density and spike length, and under stress conditions, the number of kernels per spike, the grain filling rate, grain filling period and straw yield, were considered as the traits affecting grain yield.

Microgreens are young plants that have gained popularity among consumers due to their high nutritional value. In the present study, the shelf life and nutritional properties of beet microgreens subjected to silicon and nano-silica in the post-harvest period have been investigated. Silicon and nano-silica treatments were carried out at two levels (Control and 100 mg/L as foliar spraying), after which the microgreens were harvested and kept at 4°C for 12 days. The results showed that the activity of polyphenol oxidase enzyme increased with the increase of storage time and as a result the browning of the tissue also increased. Also, with increasing storage time, the percentage of weight loss, hydrogen peroxide, malondialdehyde and carotenoid increased and chlorophyll a, b and total, total phenol, flavonoid, antioxidant capacity and vitamin C decreased. The use of silicon and nano-silica treatment decreased the activity of polyphenol oxidase enzyme and browning of the microgreen tissue compared to the control. Application of silicon increased total chlorophyll (33.75%), total phenol (2.49%) and total antioxidant capacity (39.7%) of microgreens in the post-harvest period. Also, the use of nano-silica increased the amount of total phenol (5.73%), antioxidant capacity (55%) and vitamin C (38.77%) compared to the control. In general, the results of this research showed that the pre-harvest application of silicon and nano-silica improves the nutritional characteristics of beet microgreens in the post-harvest period.

In order to investigate the effect of chemical and biological nitrogen fertilizer on canola, a field experiment was conducted as a split plot based on a randomized complete block design with three replications at the research station of the Faculty of Agriculture, Yasouj University, located in Deshtrum region, in 2019. The main factor consisted of nitrogen fertilizer (zero, 25, 50, 75, 100 and 125 kg/ha of pure nitrogen from urea source) and the secondary factor consisted of nitroxin biofertilizer contained Azotobacter and Azospirillium bacteria (use and non-use). The results showed that nitrogen fertilizer and nitroxin had a significant effect on all investigated traits. Nitrogen fertilizer significantly increased plant height, number of lateral branches, chlorophyll index and oil yield. The highest grain (8790.60 kg/ha) and biological (23910.93 kg/ha) yield were obtained in 125 kg/ha of nitrogen and the use of nitroxin. With the consumption of 125 kg/ha of nitrogen and nitroxin, the lowest percentage of seed oil, and contrastingly the highest percentage of seed protein (36.65%) was obtained. In general, combined application of biofertilizer with chemical nitrogen increased grain, biological and oil yield. Nitroxin bio-fertilizer could reduce the consumption of chemical nitrogen fertilizer. The results showed that there was no significant difference between the application of 50 kg/ha of nitrogen + bacteria and the application of higher levels of nitrogen (75, 100 and 125 kg/ha) alone in most of the investigated traits.

Rapeseed needs a sufficient amount of nitrogen for optimal seed yield, but the efficiency of this plant in using nitrogenous (N) fertilizers is low, which causes an increase in N consumption in the cultivation of this plant. The need to maintain a high grain yield necessitates the use of a suitable timely program and manage the consumption of N fertilizers. Thus, a field experiment was conducted at the Research Station of Agriculture and Natural Resources of Khuzestan University during 2020-2021 growing season to evaluate the effect of preceding crop and N fertilizer on grain yield of rapeseed. The experiment was carried out as split plots based on a RCBD with three replications. Preceding crops (clover-barley mixture, rapeseed, corn, fallow, mung bean, rice and wheat) were allocated to the main plots and N levels (0.0, 100, 160 and 220 kg ha-1 N from the source of urea fertilizer) were assigned to the sub plots. Results indicated that the grain yield of rapeseed depends mostly on grain number, but the grain yield components (including pods number per plant, grain number per plant, grain number per pods) were mainly affected by the main effect of preceding crop and nitrogen. With the application of 100, 160 and 220 kg ha-1 N the number of grains per pod increased by 34%, 39% and 33%, respectively. The number of grains per plant was also increased by the application of nitrogen fertilizer, where all three levels of nitrogen fertilizer resulted in more than 200% increases in this grain yield attribute. The highest grain yield of rapeseed (3877 kg ha-1) was observed when mung bean was used as preceding crop and 220 kg ha-1 N fertilizer was applied, though it was not significantly different from the treatments of mung bean preceding crop and application of 160 kg ha-1 nitrogen fertilizer (with the production of 3105 kg ha-1 grain) and fallow preceding and 160 kg ha-1 N fertilizer. The lowest grain yield of rapeseed was obtained when corn and rapeseed were used as preceding crops and no N fertilizer was applied, as these preceding crops resulted in only 488 and 497 kg ha-1 grain of rapeseed, respectively. Rapeseed had the highest oil yield (1645 kg ha-1) with mung bean being the preceding crop and 220 kg ha-1 N application. It seems that for achieving the highest oil yield of rapeseed, mung bean preceding crop and 220 kg ha-1 N can be focused on for the next researches.

Strawberry (Fragaria × ananassa Dutch) is a widely grown fruit crop in the world due to its high aroma, taste, and nutritional value. In this study, the effect of foliar application of titanium dioxide nanoparticles on phytochemical modifications of strawberry cv. Sabrina under deficit fertigation conditions was investigated. The interaction effect of titanium dioxide nanoparticles (0, 6 and 12 mg L-1) and deficit fertigation (90, 110 and 130 mL) on some morphological, antioxidant and phytochemical factors of strawberry cv. Sabrina, such as fruit width, length, weight and yield, total phenol and flavonoid content, total antioxidant capacity, antioxidant enzyme activity, acid ascorbic content, total anthocyanin, iron and zinc content were investigated. Results showed that the interaction of titanium dioxide nanoparticles and the amount of nutrient solution on vitamin C content, antioxidant enzymes activity and iron content was significant. The highest fruit width (4.73. cm), fruit length (3.71 cm), fruit fresh weight (52.2 g), fruit yield (527 g) and vitamin C content (51.1 mg 100 mL-1) were observed in the presence of 130 mL of deficient fertigation and 12 mg L-1 titanium dioxide nanoparticles treatments. In contrast, the highest catalase (1.96 u/g FW), guaiacol peroxidase (2.42 u/g FW) and ascorbate peroxidase (2.29 u/g FW fruit) were observed upon exposure to 90 mL of deficient fertigation and 12 mg L-1 titanium dioxide nanoparticles treatments. In conclusion, deficit fertigation conditions along with the use of titanium dioxide nanoparticles improves morphological and phytochemical properties of strawberries

In order to study the effects of nanoparticles and biofertilizers on chlorophyll fluorescence indices and some physiological traits of triticale (Triticosecale Wittmack) under salinity stress, a factorial experiment was conducted based on a randomized complete block design with three replications in the research greenhouse of Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardebili in 2021. Experimental factors included salinity (non-saline control, 35, and 70 mM NaCl), application of biofertilizers (PGPR) (biofertilizers-free control, application of Azospirilum, Pseudomonas, combined application Azospirilum and Pseudomonas) and nanoparticles foliar application (foliar application with water as control, nano iron oxide foliar application, nano silicon, combined foliar application of nano iron-silicon oxide). The results showed that both application of PGPR and foliar application of nanoparticles under non-saline condition increased quantum yield (64%), maximum fluorescence (69%), variable fluorescence (175%), chlorophyll index (48.1%), leaf nitrogen content (35.3%), leaf relative water content (49.7%) and stomatal conductance (81.4%) and grain yield per plant (44.5%) in comparison with biofertilizers-free and nanoparticles foliar application under 70 mM salt condition. Maximum of minimum fluorescence (178) and electrical conductivity (126) were obtained at the highest salinity level, i.e. 70 mM NaCl. Based on the results of this study, it seems that application of bio fertilizers and nanoparticles foliar application may improve the grain yield of triticale under salinity stress.

To evaluate the phenological stages and yield of wheat cultivars in response to the change of planting date and application of paclobutrazol, a field experiment was conducted in two years, 2020-2021 and 2021-2022, in Izeh city located in the northeast of Khuzestan, Southwest Iran. The experiment had three replications in a split factorial randomized complete block design. The main factor included planting date (November 16, December 11, and January 5) and the sub factors in the factorial form included cultivars (Karim, Mehrgan, and Chamran2) and the application of paclobutrazol (0, 60, 120 mg/L). In both years, the highest seeds/m2 (18847) belonged to Chmaran2 genotype when sown on 16 November and received 60 mg/L paclobutrazol. When the genotypes were sown in the delayed planting date of January 5, application of 60 and 120 mg/L paclobutrazol led to an increase in seed yield compared to the 0 paclobutrazol. With the application of 60 mg/L paclobutrazol, the seed yield of Chamran2 genotype was higher on the planting dates of November 16 (6941 kg/ha) and December 11 (6779 kg/ha), compared to other paclobutrazol levels. Chamran2 and Karim genotypes indicated the greatest and smallest number of days and growing degree days, respectively, in different stages of growth and development. However, these genotypes did not show significant difference in terms of biological yield, grain yield, and harvest index. When plants were sown on January 5, the length of the plant growth period from the planting to physiological maturity was reduced by 34 days compared to when sown on November 16. Overall, the effect of paclobutrazol on seed yield was positive, and the consumption of 120 mg/L paclobutrazol moderated the negative effects of the delayed planting of the examined wheat genotypes.

It is important to determine the appropriate planting density in the conditions of using old seedlings of paddy rice. For this purpose, a field experiment was conducted as a randomized complete block design at Qaemshahr, Northern Iran, in four replications and in two years, 2020 and 2021. Plant densities consisted of manual-traditional planting of up to 11 hills/m2 (with unequal planting spaces and common in the region) as control and manual-equidistant planting with 25 hills/m2 (with planting spaces of 20 × 20 cm and recommended by the Rice Research Institute of Iran) and machine-planting with 15.9, 20.8 and 20.8 hills/m2 (with planting spaces of 30 × 21, 30 × 16 and 30 × 12 cm, respectively). The paddy rice seedlings aged 45 d in manual-planting and 35 d in machine-planting. The results showed that the number of days from transplanting to flowering and flowering to maturity for machine-planting densities were greater than those of the control and 25 hills/m2 in manual-equidistant planting. The interaction effect of year × planting density was significant only for the flag leaf length and plant height. The greatest panicle length and flag leaf length were obtained when the rice plants were sown in a density of 25 hills/m2 in manual-equidistant planting. The greatest panicles/m2 and the percentage of grain-bearing spikelets were obtained when rice plants were sown by the machine. The maximum grain yield was obtained from planting density of 25 hills/m2 in manual-equidistant planting (8022 kg/ha).  The planting densities of 15.9, 20.8 and 27.8 hills/m2 in machine planting with 8034, 8236 and 8168 kg/ha grain yield ranked next as they out-yielded the control by 19%, 19%, 21% and 21%, respectively. It was concluded that machine planting with planting densities of 15.9, 20.8 and 27.8 hills/m2 is advantageous, at least when using old paddy rice seedlings.