فصلنامه اکوفیزیولوژی گیاهان زراعی
پیاپی 57 (بهار 1400)

Today, intercropping as a key strategy of sustainable agriculture, is appreciated by both researchers and farmers in increasing efficiency of environmental resourceing uses, reduce damages due to environmental stresses, and improve the farm income. To this end, a split plot experiment based on a randomized complete blocks design with three replications was conducted at the Research Farm of Gonabad University.Main factor, comprised of  25% safflower + 75% chickpea, 50% safflower + 50% chickpea, 75% safflower + 25% chickpea, and 100% safflower + 100% chickpea intercropping patterns, and sole cropping of the two plants. Subfactors consisted of control (without foliar spray) and foliar spraying of 3 g.lit-1 Fe and Zn. The research results showed that the highest values of branches number (10.5) and head number per plant (22.5) of safflower were achieved from 25% safflower + 75% chickpea and 50% safflower + 50% chickpea intercropping, respectively and the highest seed yield (2070 kg.ha-1) from sole cropping. The branch and head number per plant, 1000-seed weight, and seed yield of safflower were increased significantly due to micronutrient foliar application as compared with control. The plant height (26.4 cm) and seed yield (1739 kg.ha-1) of chickpea showed the highest value in sole cropping while the highest values of pod number per plant (31.9) and seed number per plant (22.2) were obtained from 25% safflower + 75% chickpea intercropping. Micronutrients foliar application improved plant height, pod number per plant, pod length, and seed number per plant of chickpea. The land equivalent ratio values ranged from 1.12 to 1.52. The changes in water use efficiency indices were also higher in all intercropping patterns compared with sole cropping, and the highest value (1.31) was achieved from 75% safflower + 25% chickpea intercropping treatment. The aggressivity index indicated the dominance of safflower over chickpea. All of the intercropping treatments, except for 100% safflower + 100% chickpea pattern, showed real yield increase. The highest value of intercropping advantage (0.51) was obtained from 25% safflower + 75% chickpea treatment while the monetary advantage index (26454751) and the relative total value (1.44) were higher in 100% safflower + 100% chickpea intercropping as compared to the other cropping patterns.

To evaluate the effect of biofertilizer and sulfur on yield and morphophysiological traits of three wheat genotypes. A split plot factorial design experiment based on completely randomized block design with four replications was performed at Gharakhail and Baykola research stations of Mazandaran province in 2014-2015. The wheat genotypes were Gonbad, Ehsan and Tirgan; the sulfur treatments consisted of levels of zero, 250 and 500 kg.ha-1 (along with Tiobacillu ssp < /em>) and biofertilizer of zero and two l.ha-1 (via treating seeds). The traits studied were plant height, leaf area index, number of fertile spikes, seed yield, plant fresh and dry weights, and protein percentage of seeds. Results showed that Flawheat biofertilizer had significant effect on leaf area index, plant dry weight, number of fertile spike and seed yied, and application of two liters of biofertilizer improved the traits under study. The highest plant height (117.7 cm) was observed in Tirgan cultivar by using 2 kg.ha-1 of flawheat biofertilizer and 250 kg.ha-1 of sulfur. In all three cultivars of Gonbad, Ehsan and Tirgan, consumption of 2 l.ha-1 of flawheat and 250 kg.ha-1 of sulfur increased wheat dry weight compared to the control. Tirgan cultivar with 5298 kg.ha-1 produced highest seed yield by using two liters of Flawheat and 250 kg of sulfur per hectare. Based on the results obtained, it can be concluded that Tirgan among the three cultivars studied in the central and eastern regions of Mazandaran province, produced higest seed yield by using of 250 kg.ha-1 of sulfur and the application of two liters per hectare of Flawheat.

Optimum use of fertilizer plays a key role in enhancing the yield of rice and other crops. The use of nano-fertilizers can be an effective strategy in optimizing fertilizer use in croping systems and achieving sustainable agriculture. This research was carried out to study the effect of nano-fertilizers spraying compared with common chemical N.P.K fertilizers use on morphological traits, yield and yield components of rice in Sari, Mazandaran province for two years (2016 and 2017). A split plot experiment, based on randomized complete block design with three replications was conducted. The main factors were two rice cultivars (Tarom and Shiroudi) and a sub plots including fertilizer treatments in 10 levels, consisting of control (without fertilizer), common fertilizers of nitrogen (N), phosphorus (P), potassium (K) and NPK, and nano-fertilizers of nitrogen (Nano-N; chelated nitrogen 17%), phosphorus (Nano-P; chelated phosphorus 17%), potassium (Nano-K; chelated potassium 27%) and NPK (Nano-NPK), plus simultaneous application of NPK and Nano-NPK (NPK+Nano-NPK). The results showed that, use of conventional fertilizers and nano-fertilizers, including the use of NPK and Nano-NPK, increased the yield and yield components of both rice cultivars. Most of the fertilizer levels (N, K, NPK fertilizers in Tarom and P, K and NPK fertilizers in Shiroudi), the use of nano-fertilizers was more affective than conventional fertilizer and increased seed yield. Application of Nano-NPK increase yield of Tarom and Shirodi cultivars by 22.54% and 12.12%, respectively as compared to the use of NPK. Since the application of chemical fertilizers is indispensable for obtaining proper yield in plants, the use of nano-fertilizers, especially Nano-NPK treatments, can be a good strategy to optimize the use of fertilizers in rice fields.

To evaluate the effect of different levels of NPK nutrition on some morpho-physiological characteristics and seed yield of quinoa, a randomized complete block design experiment was carried out in Shahid Bahonar University of Kerman in 2019. In this study, response of quinoa (Titicaca variety) to seven fertilizer combinations, consisting of nitrogen, phosphorus and potassium (N: K: P, 30:25:20, 60:50:40, 90:75:60, 120:100:80, 150:125:100, 180:150:120 kg.ha-1) were investigated for plant height, number of branch, panicle length, 1000 seed weight, seed yield, content of photosynthetic pigments, leaf area index, crop growth rate, seed protein content and seed nutrients. The results indicated that the effect of NPK nutrition treatments on all measured traits were significant. The highest mean of Chl a, Chl b, Chl a+b, carotenoid, LAI, CGR and seed protein content belonged to combination of 120: 100: 80 which was not significantly different from combination of 90: 75: 60, in terms of Chl a and LAI. In this study, the highest mean of panicle lengths, number of branches, 1000 seed weight and seed yield were recorded for combination of 120: 100: 80 which were not significantly different from combination of 90: 75: 60, in terms of panicle length and seed yield. According to the results, thus, it can be concluded that combination of nitrogen, phosphorus and potassium fertilizers with a ratio of 90: 75: 60 are appropriate to achieve maximum seed yield for research location under Kerman climatic conditions and avoid overuse of chemical fertilizers.

Water resource limitation in the end of growth season of rapeseed crop is one of the main problems for production and development of this crop in semi-arid regions of Iran. Therefore, introduction of compatible and tolerate cultivar to this condition is crucial for growth expansion of rapeseed. To identify and introduce suitable rapeseed cultivar for delayed planting, a split plot experiment based on randomized complete block design with three replications at Research Field of Seed and Plant Improvement Research Institute of Karaj, Iran was conducted in 2015-16 and 2016-17. In this study, sowing dates were October 7 (normal) and November 6 (delayed planting) asseinged to the main plots, and rapeseed cultivars including ES Hydromel, ES Alonso, ES Darko, ES Lauren and Ahmadi to the sub-plots. To introduce of tolerate cultivar to drought tolerance indices, experimental plots were subjected to two common irrigation conditions (control) and irrigation interruption from the flowering stage onwards (drought stress). Combined analysis of data indicated that delayed planting significantly reduced rapeseed oil percentage and oil yield. According to the results ES Hydromel cultivar produced the highest oil percentage (41.61%) and oil yield (1381.08 kg.ha-1). Based on the selected indices of this study, including geometric mean productivity, stress tolerance index, and mean productivity, the most tolerant cultivar under both normal and delayed planting was ES Hydromel and the least tolerant cultivar under normal conditions was ES Lauren and under stress conditions was ES Darko. The results of cluster analysis also confirmed the formation of two clusters, ES Darko, Ahmadi and ES Lauren in belonged to sensitive cluster and ES Hydromel and ES Alonso to the tolerant cluster.

The research was carried out to evaluate the response of safflower (Carthamus tinctorius L.) to salinity, drought and combined salinity- drought stresses at its vegetative stage and share of their effects on reduction of yield, yield components and photosynthesis of plant. For this purpose, a split plot experiment based on randomized complete block design was carried out at Agricultural Education Center of Kabotarabad- Isfahan in 2016-2017. In this study, response of spring safflower (Sofeh variety) to four salinity stress levels (2.5, 5, 10 and 15 dS/m) and four drought stress levels (100%, 80%, 60% and 40% F.C.) at vegetative growth stage were evaluated. The results showed that mean values of most traits were significantly reduced with increasing salinity and drought stress levels, in such a way that severe drought (Irrigation based on 40% field capacity) and salinity (15 dS/m) treatments produced lowest values for all traits. Seed oil content decreased with increasing salinity but this decrease (7.4%) was significant only at highest salinity level (15 dS/m). The highest level of combined salinity-drought stress decreased seed yield (87.13% decrease) more than the highest level of each of drought (71.40% decrease) and salinity (55.56% decrease) stresses as compared to control treatment (without drought and salinity stress), and the share of drought stress in reduction of seed yield was higher than the salinity stress (71.40% and 55.56%, respectively). Thus, growing safflower with minimum loss of seed yield, by irrigation with 80% F.C. and water salinity with 5 dS/m at the vegetative growth stage is possible.

To investigate the effect of drought stress and foliar application of ascorbic acid, salicylic acid and methanol, and post-harvest seed deterioration, two separate experiments were carried out as split plot based on randomized complete block design with three replications on maternal plants in field conditions and a factorial based on completely randomized design considering by using seed under storage conditions. The main plots were consisted of three irrigation levels, irrigation after 60 mm evaporation from basin, considered as control treatment (optimum irrigation), cessation of irrigation at flowering and silique stages, and sub plots consisted of 10 levels of foliar application, (100, 200, 300 mg.lit-1 ascorbic acid, 100, 200, 300 μmol salicylic acid, 10, 20, 30 vol% methanol and the foliar application with distilled water as control treatment). Seeds obtained of maternal plant were evaluated under no-storage (control) and storage at 40°C for one month. The results showed that foliar application of ascorbic acid (300 mg.lit-1) increased seed yield by 29% under optimum irrigation as compared with non foliar application under the same irrigation condition. Cutting off irrigation of maternal plant decreased radical and plumule weights under both no-storage and one-month storage conditions. The maximum germination percentage belonged to foliar application of ascorbic acid (300 mg.lit-1) under optimum irrigation condition at both no-storage one-month stored seed. The minimum germination percentage belonged to no use of growth regulators application and cessation irrigation at flowering stage. Maternal plants which sprayed with ascorbic acid contained the highest seed weight vigor index at all irrigation treatments.

Selection of tolerant cultivars to water stress in areas with reduced rainfall is important. A split plot experiment based on a randomized complete block design with three replications was conducted at the Ardabil Agricultural Research Center during 2015-2016. The experiment factors consisted of three irrigation regimes: full irrigation (with 100% water requirement) considered as control and 15 and 30 days irrigation intervals assigned to main plots and five potato cultivars consisted of: 397081-1 and 397082-10 Clones and Agria, Caesar and Savalan cultivars assigned to sub plots. In this experiment, clones 397082-10 and 397081-1 and Savalan cultivar had relative superiority in terms of tuber yield, tuber dry matter, water use efficiency and high marketable tuber yield compared to Caesar and Agria. Also, in both years of experiment, the trend of variation of these cultivars for the studied traits were similar under deficit irrigation interval of 15-days. The results were not significantly different against control treatment. As a result, 15-days interval irrigation can be used to save water in the Ardabil area.