نشریه فیزیولوژی گیاهان زراعی
پیاپی 55 (پاییز 1401)

Oilseeds are considered as one of the most essential food components in human consumption as well as animal feed. While drought is one of the most important abiotic stresses in the climate change scenario and its intensity is expected to increase in the future, which has an adverse effect on the yield and nutritional quality of major oilseeds worldwide. Sunflower is an important oilseed product that has an 8% share in the production of oilseeds in the world. In order to investigate the effect of different irrigation regimes on grain yield and some physiological indices, experimental sunflower cultivars were performed in the form of split plots in a randomized complete block design with four replications in Ahvaz Agricultural Research Center during 1995 and 1996. Irrigation regime includes irrigation after evaporation of 50, 70 and 90 mm from Class A evaporation pan as no stress, mild and severe stress, respectively, in the main plots and six cultivars Progress, Farrokh, Barzegar, Rekord, Azargol and Lakomka in Sub-plots were placed. . The results of combined analysis of variance showed that the three-way effect of year, irrigation regime and cultivars was significant in superoxide dismutase, ascorbate peroxidase and grain yield and in other traits the interaction of irrigation regime and cultivars or main effects was significant. The highest grain yield (2529 kg / ha) in the first and second year of the record and irrigation of 50 mm was obtained from the evaporation pan. In general, the record cultivar had higher yields than other cultivars during all two years of experiment at all levels of irrigation. The highest amount of superoxide dismutase and ascorbate peroxidase enzymes was obtained from the record cultivar and irrigation regime of 90 mm from the evaporation pan in the second year. The results showed that the highest oil yield (1101 kg / ha) and leaf area index from evaporation stress level of 50 mm were from evaporation pan and record cultivar. The highest amount of catalase was obtained from the level of severe stress and the record cultivar. The highest amount of guaiacol peroxidase was observed in the record cultivar and the 90 mm diet from the evaporation pan. The highest amount of width (7.438 mm) and grain diameter (4.928 mm) from the application of non-stress water treatment and record cultivar and the highest grain length (13.9 mm) in Lakomka cultivar and 50 mm evaporation treatment Evaporation was obtained from the pan. According to the results of this experiment, the record cultivar and irrigation of 50 mm of evaporation pan is suitable for Ahvaz region.

In order to study evaluation of resistance to dryness  in two species of Bromos by using micorhyza symbiosis, a test has been conducted in split split plot in the form of block basis plan fully randomly by four iterations  in two agricultural  years  of 1396_1397 and 1397-1398 in the south of Tehran  province. The main  court consisted of dryness tension in three levels: 1-control(without tension in field capacity limit)(s1), 2-average tension (60%  field capacity )( s2), 3-intensive tension (40% field capacity )(s3)and minor  court also consisted of using  micorhyza fungus in three levels including:1-without micorhyza as 1- control (M1), 2-the specie of Glomus intraradices (M2) 3- specie of  Glomus mosseae (M3), two species  of Bromus plant considered as minor court  in two levels including:1_ (B1)Bromus kopetdaghensis (B1) -and Bromus tometolus (B2).Results showed that dryness tension  resulted in decrease of  number of leaf . Productivity geometrical average  rate (MP) and productivity arithmetical average (MP)in the average tension  condition was higher than intensive tension. Using Micorhyza species (M2) resulted in significant increase of  the number of  leaf, grass qualityand productivity  arithmetical  average  index. In the  comparison of average (S×M), tension  and application of micorhyza resulted in increasing  root length and dry weight of entire plant.The most  dry weight of entire plant in (S3M2)resulted to the rate of 6/8 grams and  root length  in (S3M3)gained 7/37 cm.Application of (M2) in the third level resulted in  1/21 %of dry weight of entire plant toward lack of application of micorhyza in this tension rate.Also tension resulted in  decrease of grass quality and in every three levels of dry tension ,application of micorhyza  resulted in significant increase of grass quality toward control and this increase in (M2)was more than (M3).In this test the greatest root length gained in (S3B2).In the comparison between interaction average (M×B),the greatest  root length  gained in (M3B2)condition.Based on the result of  interaction average  comparison,(S×M×B),the highest height of plant gained in the treatment (S1M2B2).The greatest  GMP in both years in tometolus grass species gained  along with the application of G.intraradices micorhyza species (M2B2Y1) and (M2B2Y2). Based on results of interaction  (S×M×B×Y),the highest stand to dryness index gained (S3M2B2Y2) and (S3M2B2Y1).In general, the species  Bromus tometolus and using of fungus species  Glomus intraradices suggested for this region in dryness tension condition.

Despite genetic advances, the emergence of limiting factors such as climate, soil and crop management has led to a significant gap in many areas between farmers harvest performance and genetic yield potential. Knowing the limiting factors and proper planning and determining strategies to increase the adaptation of crops to these possible changes, causes the appropriate response of crops to these changes. For this purpose, the present study was conducted to investigate the effect of planting date and cultivar on yield and experimental physiological traits as a split plot in the form of a randomized complete block design with three replications in the crop year 2020-2021 in the Faculty of Agriculture, Lorestan University. The main factor included the four planting dates of 6 October, 21 October, 5 November, 20 November and the secondary factor of the cultivar, which included Chamran 2, Sirvan and Mihan. The results of analysis of variance showed that the simple effect of planting date on all studied traits was significant at one percent probability level and the simple effects of cultivar on photosynthesis rate, grain yield at one percent probability level and mesophilic conductance, stomatal conductance at five percent probability level were significant. Planting date was 6 October due to early sowing and occurrence of growth stages with temperatures lower than plant tolerance and planting date was 20 November due to delay in sowing time reduced seed yield. In general, the appropriate planting date, while increasing the optimal conditions for wheat cultivars, the growth and physiological characteristics of the plant, including photosynthetic components, provide favorable conditions for better plant growth and ultimately increase grain yield. In this study, this planting date of 5 November and Mihan cultivar is recommended as the best planting date and cultivar for Khorramabad region and similar climatic regions, respectively.

This study was conducted to investigate the effect of different irrigation regimes on forage quantity, water and energy productivity of two maize cultivars during the 2017-18 as experiment of split plots in block design with three replications in the northwest of Isfahan, Iran. The main plots and the sub-plots included three levels of irrigation (100%, 80 and 60% full irrigation) and two cultivars of maize (704 and Maxima).Results indicated that, water level and genotypes, had significant effect (p<0.01) on fresh and dry forage yield ,fresh and dry forage of water and energy productivity. The highest fresh forage yield and water and energy productivity observed in 100% irrigation level in cultivar 704 (69 t.ha-1, 10 kg.m-3 and 0.74 kg.mJ-1, respectively).While, the highest dry forage yield and water and energy productivity in same level found in Maxima cultivar (23 t.ha-1, 3.4 kg.m-3 and 0.25 kg.mj-1 in, respectively). The highest fresh forage yield and water and energy productivity observed in 100% irrigation level in 704 (69.2 t.ha-1, 10.4 kg.m-3 and 0.7 kg.mj-1). While, the highest dry forage yield and water and energy productivity at the same level were observed in Maxima (23.3 t.ha-1, 3.4 kg.m-3 and 0.25 kg.mj-1). In general, due to the selection of suitable cultivars in arid areas, Maxima are more suitable than 704. Although, the input energy of both cultivars is equal with respect to equal consumption inputs. However, due to environmental effects of consumption of inputs, Maxima is superior. Therefore, by choosing the appropriate forage cultivar, an important step can be taken in sustainable improvement and problem of water shortage in arid and semi-arid regions.

Drought stress is one of the most severe environmental stresses which is a significant role to ‎yield reductions in arid and semi arid. In this regard, the application of silicon ‎in combination with microelements such as iron is a recent, innovative strategy to ‎overcome the damaging effects of drought. So, in order to study the effect of nanoparticles foliar application (iron and silicon) on yield, grain filling components and some physiological traits of safflower under rained and supplementary irrigation conditions, an experimental as factorial was conducted based on randomized complete block design with three replications at the Agricultural Research Station of Ardabil (Alarouq) in 2021-2022. The experimental factors were included irrigation levels (no irrigation or rainfed condition as control, supplementary irrigation at 50% heading-bud and flowering stages according with 55 and 65 BBCH code respectively) and nanoparticles foliar application (foliar application with water as control, foliar application of 1 g.L-1 nano iron oxide, 50 mg.L-1 nano silicon, foliar application 0.5 g.L-1 of nanoiron oxide and 25 mg.L-1 nano silicon). The results showed that nanoparticles foliar application of iron and silicon under supplementary irrigation conditions at the heading-bud stage increased chlorophyll index (35.44%), relative water content (44.25%) and stomatal conductance (32.93%), rate and grain filling period (7.47 and 36.33%  respectively), the number of grain per bud (45.06%), 1000 grains weight (53.06%) and grain yield (43.77%) in comparison with no foliar application of nanoparticles under rainfed conditions. Based on the results of this study, it seems that foliar application of nanoparticles and supplementary irrigation could be utilized as a rapid, easy and effective approach to reduce drought-induced damages on safflower under rainfed conditions due to improving of grain filling components and some physiological traits (such as chlorophyll index, relative water content and stomatal conductance).

In order to evaluate the response of quantitative and morphological traits of spring wheat cultivars to planting arrangement and density in late planting, this experiment was conducted in the cropping years of 2014-15 and 2015-2016 as twice split plots in a randomized complete block design in three repetition was performed on agriculture research center in Safiabad Dezful. Treatments include three cultivation method flat strip, two lines on the bed and three lines on the bed in the main plots, three seeds used including: 400, 600 and 800 seeds m-2 in the subplots and four genotypes of spring wheat including: Chamran, Baj, Chamran 2 and ER-92-19 were in the sub-plots. In this study, combined analysis for grain weight and spike length and other characteristics were analyzed in separate years. The results of analysis of variance in the first year showed that the effect of planting method, density and cultivars on grain yield was significant. Also, the effect of genotype in the second year on the number of spikes per square meter, number of spikelets per spike, number of seeds per spike, stem height and awn was significant.  Also, the effect of genotype in the second year on the number of spikes per square meter, number of spikelets per spike, number of seeds per spike, stem height and length of awn was significant. Most yield belong to three line on bed cultivation method (793.56 kg ha-1), 600 seed rate (754.78 kgha-1) and Baj cultivar (948.34 kgha-1). In second year, cultivation method was non-significant and the most yield belonged to 800 seed rate (3435.18 kgha-1) and Baj cultivar (5704.19 kgha-1). In general, it can be concluded that the yield of spring wheat in very late planting can be increased economically by selecting the appropriate cultivars, density and arrangement and this ability in areas such as northern Khuzestan province for three or four times in one Years of interest.

One of the most important challenges of agricultural production growers and food security is environmental stress (biotic and Abiotic) specially caused by global changes. Sustainable yield could be accessible by identifying environmental stresses using physiological studies. Physiological and phenotypical researches on crop have been based on labor-intensive conventional, distractive and time-consumer methods, as laborious and farm tasks, for many years. To address this issue, rapid approaches such as using machine vision technologies, machine learning and deep learning's algorithms, are in urgent. These methods have had positive effect on prediction or identification of stresses by monitoring crop phenotypical and physiological changes. In this paper, the latest image technology, vegetation indices and a diversity of deep learning algorithms involved in plant stress, are reviewed. Furthermore, the most functional algorithms of convolutional neural networks are summarized. On the other hand, the current challenges of application of image processing approaches and artificial intelligent in plant stressed are discussed.