فصلنامه اکوفیزیولوژی گیاهان زراعی
پیاپی 58 (تابستان 1400)

This study was performed in a factorial experiment based on randomized complete block design with three replications on Adel chickpea cultivar during 2017-2018. Seed priming consisted of two levels (non-priming and hydropriming) and spraying nitrogen and glycine betaine with six levels (no spraying, as control, zero concentration (water spray), 3% urea, 100 mM glycine betaine, 200 mM glycine betaine, and glycine betaine 200 mM + urea 3%). Interaction of priming by foliar application on biological and grain yields was significant at 1%probabilitylevel.The highest biological yield (2668kg.ha-1) and grain yield (1301 kg.ha-1) were obtained with combined priming and consumption of 200 mM glycine + 3% urea and the lowest yield was related to non-priming and non-spraying priming. Priming also improved the harvest index, number of seeds per plant, number of pods per plant, 100-seed weight and number of active nodules. The effect of foliar application of plants by glycine betaine and urea on number of grains per pod and grain protein percentage was significant. The highest values of these traits belonged to foliar application of plants by glycine betaine with concentration of 200 mM + 3% urea. Hydropriming significantly increased grain yield, harvest index, grain weight, and number of seeds per plant. Hydropriming also allowed the plant to initiate flowering and pod forming earlier. According to the results of this study, the use of hydropriming treatment and spraying of nitrogen and glycine betaine respectively would be recommended to improve the quality and quantity of rainfed chickpea in Kuhdasht, Lorestan province.

To evaluate the effect of different rates of biochar and humic acid applications on physiological characteristics and grain yield of single cross 704 hybrid corn under water deficit stress, a split split plot experiment based on a randomized complete block design with three replications, was conducted during two years (2017-19) at Ahvaz. The main plot devoted to water deficit stress, with three levels irrigation (after depleting 30, 40, and 50% of field capacity as optimum irrigation, moderate stress, and severe stress, respectively) and sub-plot to biochar with 2 levels, non-application of biochar (control) and application of 4 tons per hectare of biochar, and the sub-sub plots to humic acid with 4 levels non-application of humic acid (control), and application of 2, 4, and 6 liters per hectare of humic acid. The results showed that the interaction effect of water shortage by biochar stress and water shortage by humic acid stress on grain yield, 1000-grain weight, number of grains per ear, superoxide dismutase, chlorophyll index and catalase were significant at 1% probability level. Under severe stress conditions grain yield (36.54%), number of grain per ear (36%) and leaf area index (30.36%) decreased and activity of superoxide dismutase (37.7%) increased. Acidic acid had a significant effect on all traits under study. The highest grain yield (8995.18 kg.ha-1) was related to irrigation treatment after 40% depletion of field capacity and application of 4 tons per hectare of biochar. Based the results obtained application of 4 liters per hectare of humic acid under moderate moisture stress conditions, could be recommended in arid and semi-arid conditions to save water consumption and reduce the effects of water deficit stress.

Due to the limit of water availability in rice fields, alternate wetting and drying irrigation are used instead of continuous submergence to reduce water consumption in rice fields. Therefore, this study was conducted to evaluate the effects of different irrigation regimes and N fertilizer rates on yield, and the content of micronutrients in brown and white rice at Rashat during cropping seasons of 2016-2017 and 2017-2018. Experiment was arranged in split plot based on complete randomized block design with 3 replications in which water regimes continuous submergence (I1), 7 (I2) and 15 (I3) day interval irrigation were asseigned as main factor and nitrogen fertilizer levels (50 (N1), 75 (N2), and 100 (N3) kg.ha-1) as sub factor, and cultivars, Gilanh (C1) and Hashemi (C2) as sub sub factor. Results showed that the effect of year on yield and number of panicle per m2 was significant. The interaction of different irrigation treatments and N fertilizer and cultivar on the number of panicle per m2 in 2017, yield in 2017 and 2018, and micronutrient content were significant. Increasing the irrigation intervals decreased number of panicle per m2, number of seed per panicle, weight of 1000 grain, and yield, while the consumption of 75 and 100 kg.ha-1 of nitrogen fertilizer increased these traits in all three irrigation treatments compared to the level of 50 kg.ha-1 of nitrogen fertilizer. Gilaneh in all irrigation treatments showed higher yield, number of panicle per m2, and number of seed in panicle. Also, increasing of the irrigation intervals increased the content of micronutrients in brown and white rice seeds. The consumption of 75 and 100 kg.ha-1 of nitrogen fertilizer increased these traits as compared to the other levels of nitrogen fertilizers. The highest content of Zn, Cu, Fe, and Mn was observed in brown and white rice at irrigation interval at 14 days and 100 kg.ha-1 nitrogen fertilizer application. The consumption of 100 kg.ha-1 of nitrogen fertilizer increased the quantitative and qualitative grain yield of both cultivars as compared to the other two levels of nitrogen fertilizer and to irrigation regimes. Proper level of fertilizer would compensate the adverse effects of increasing irrigation intervals.

Simulation of rice yield and its water productivity studied using AquaCrop, WOFOST and CropSyst models, in an experiment at Khuzestan Agricultural Research Station. In this study, three types of planting methods (D1: transplanting, D2: direct seeding, and D3: dry bed seeding) and three rice cultivars (V1: Red-Anbori, V2: Champa, V3: Danial) were considered. Results of MBE (0.36 t.ha-1), RMSE (0.1.07 t.ha-1) and NRMSE (0.14 t.ha-1). MBE, RMSE and NRMSE values for water productivity calculated by using AquaCrop model were -0.11 kg.m-3, 0.40 kg.m-3 and 0.15, respectively. The values for yield simulation using WOFSOT model were 0.06 ton.ha-1, 1.14 t.ha-1 and -0.01, respectively, and aforementioned values for water productivity simulated by WOFOST were 0.15 kg.m-3, 0.40 kg.m-3 and -0.13, respectively. The mentioned values for CropSyst simulated as 0.11 t.ha-1, 0.80 t.ha-1 and -0.24 for yield and 0.15 kg.m-3, 0.40 kg.m-3 and -0.14 for water productivity, respectively. According to the results, accuracy for all models were accepted to simulate rice yield and water productivity. However, WOFOST accuracy was better than the other models in most treatments. Thus, it is recommended to use WOFOST for simulation of rice yield and water productivity at different rice cultivars.

Tobacco is cultivated as a valuable crop in more than one hundred countries in different climatic conditions and plays an important role in the economies of some countries.This study was performed to evaluate the effect of mycorrhiza and azotobacter with application of biocahr on tobacco leaf yield, root characteristics and phytochemical components under rainfed conditions for two growing seasons at 2016 and 2017 at the Research Farm of Tirtash Tobacco Research and Education Center of Mazandaran province, Iran. A factorial experiment based on randomized complete block design with four replications and three treatments was performed. Treatments consisted of biochar (B) at three levels (0, 4 and 8 ton/ha), mycorrhiza (M), and azotobacter (A) both at two levels (without and with application). Application of 4 ton/ha biocahr increased fresh yield by 26%, cured yield 26%, root dry weight 44%, root fresh weigth 37%, root length 41%, nicotine 3%, while reduced sugar content 24% and sugar to nicotine ratio by 21% as compared to zero level of biochar application. The effect of mycorrhiza and azotobacter application on tobacco leaf yield but it was not significant, however, azotobacter had the most significant effect on nicotine content (17%). There was a positive and significant correlation between root characteristics and tobacco leaf yield. Due to the lack of significant differences between levels of 4 and 8 tons per hectare of biochar in most of the evaluated traits in terms of economic approach, the use of 4 tons per hectare of biochar along with mycorrhiza and Azotobacter to reduce the adverse of low water effects in rainfed farms and ameliorate the tobacco growth is recommended. Also azotobacter application is considered as desirable factor to increase of nicotine in tobacco.

Response of sowing date on some agronomic traits of spring canola cultivars was studied by using a split plot experiment based on randomized complete block design, during growing seasons of 2014 to 2016 at the research farm of Islamabad Gharb Station, Iran. Planting dates were considered as the main plot in three levels from October 7 to 27 and eleven spring canola cultivars as sub plot. In both years, planting dates of October 27 after emergence due to cold and frost was eliminated and the results of analysis of variance were carried out for two planting dates of October 7 and October 17. The results showed that the effect of planting date was significant on the seed yield. Mean seed yield of cultivars were 3738 kg.ha-1 on October 7th and 2245 kg.ha-1 on October17th, respectively. The cultivar Jerry produced the highest (4123 kg.ha-1) and the RGS003 lowest seed yields (2464 kg.ha-1). On planting date 7th of October, the highest seed yield was related to Jerry cultivar and the lowest seed yield was related to the Hyola 401 cultivar (1794 kg.ha-1) on the 17th of October.

Leaves are one of the most important organs of plants where food (starch and sugar) are produced. These materials are used to maintain plant tissues, growth and production of new leaves. In order to evaluate the commercial fall growing cultivars of sugar beet, their potential to produce new leaves, a factorial experiment based on randomized complete block design was conducted with three replications at Varsan Agricultural Research Station (Gorgan), during 2018 growing season. The first factor consisted of 6 commercial sugar beet cultivars (5 foreign cultivars and Sharif, domestic) and the second factor of two times at toppings in May (middle stage of growth) and June (final stage of growth). Sugar beet root yield and some important quality characteristics were measured after harvesting. The results showed that the commercial cultivars showed significant differences in terms of yield and percentage of sugar (grade) at the one percent level of probability. Highest root yield was obtained from Jrakavas and lowest from veles cultivar. The highest percentage of sugar was due to veles and lowest to Rosagold cultivars. Topping reduced borb quantity and quality of sugar beet root, while May and June toppings reduced quality and yield of sugar beet root by 8.8% and 10.2% respectively as compared to the control treatment. The interaction effect of cultivar × topping was significant in all studied traits except root dry matter.

To investigate the effect of some cover crops incontroling weed, two experiments were conducted during the fall of 2018 at Namin in Ardabil province both with three replications.The first experiment was conducted in a randomized complete block design using four speacies of winter cover crops consisting of Rye (Secale cereal L.), Hairy vetch (Vicia villosa Roth), Chickling pea (Lathyrus sativa L.) and Hungarian vetch (Vicia panonica L.). The second experiment was conducted in a factorial design, based on randomized complete blocks with two sampling times: (before the end of cover crops growth (when the cover crops were green) and 40 days after the end of cover crops growth (when the cover crops were not green). The results showed that the highest total weed density was related to Hairy vetch and Chickling pea treatments (30.5 and 27 plant per square meter, respectively) and lowest weed density to Rye and Hungarian vetch treatments (17.5 and 22 plant per square meter) respectively. The results also showed that the highest total weed density was recooded from the second sampling time (30.33 plant per square meter) and the lowest total weed density (18.16 plant per square meter) was obtained from the first time of sampling. The highest levels of Shannon-Wiener and Simpson indices were related to the clusters of Hairy vetch, Chickling pea and Hungarian vetch.  Rye and Hungarian vetch cover crops, and the first sampling time (presence of green cover crops) were the most suitable types of cover crops and sampling times to reduce weed density. It can be inferred that there is a parallel relationship between plant biomass (establishment, overwintering and regrowth of cover crops) and weed density and dry biomass. Thus, with increasing biomass of cover crops, the density and biomass of weeds would decrease.