مجله تولید گیاهان زراعی
سال چهاردهم شماره 3 (پاییز 1400)

The genotype- environment interaction is one of the most important factors causing constraints in breeding programs. The purpose of this study was genotype- environment interaction analyze for grain yield of corn in different weather conditions to identify adapted and stable cultivars for the studied environments based on the additive main effects and multiplicative interaction method and GGE biplot graphical method.

Twelve maize genotypes were evaluated for stability and adaptation in four environments (Arak, Birjand, Shiraz and Karaj). Experiment was conducted in a randomized complete block design with three replications in 2016. Stability analysis of AMMI and GGE biplot methods were used to analyze the effect of interaction between genotype and environment for grain yield.

The results of ANOVA showed that the effect of environment and effect of genotype were significant at 1% probability level and the effect of genotype- environment interaction at the 5% probability level. The multiplicative effects analysis showed that only the first component of the genotype- environment interaction was significant at 1% probability level and alone accounts for about 63% of the genotype- environment interaction variance. Biplot was obtained from mean grain yield for genotypes and environments, and the first main component of the interaction effect was the superiority of genotype 6 due to its grain yield and high stability compared to other genotypes under study. The results obtained from the graphical GGE bipolar method showed that the main components of the first and second factors were 66.97% and 57.5%, respectively, and a total of 87.53% of the total variation in the grain yield data. Biplot analysis and comparison of the environments indicated a similar reaction in Arak, Birjand and Shiraz environments in terms of grain yield of genotypes. The polygon biplot comprised the environments under study in a mega-environment where only genotype 6 was stable. Based on the ideal genotype biplot, genotype 6 in terms of both stability and grain yield was more favorable than other genotypes and showed a high degree of adaptation in all studied environments.

The results of this study, using multivariate methods, showed that the effect of environment on grain yield in corn was significant. The genotypes showed significant genetic variation. The genetic variation between genotypes was so large that it was roughly twice the environmental factor in justifying the variance of the total. The results of both methods indicated genotype 6 (KSC704) as a stable genotype. This genotype was the best genotype in all four studied environments.

Crop rotation is an annual succession of crops grown on the same land. Good crop rotation is a systematic succession of the different classes of farm crops. Crop rotation should be done in such a way to give large yields and provide the farm at the least expense of labor and fertilizes the soil. Pulses in crop rotations can improve the productivity of subsequent crops due to increased soil available N and other agronomic benefits. However, the magnitude of this effect can vary with environmental conditions, agricultural management practices and legume genotypes. Also, Legume plants can promote C storage by enhancing the formation and stabilization of soil aggregates that protect soil organic C from mineralization. In order to Evaluation of Nitrogen Use efficiency and Wheat Growth and Yield under Fertilizer Management and Pre-Cropping with crops an experiment was conducted.

A factorial experiment was designed based on randomized complete blocks with three replications and implemented on a sandy clay soil during 2012-13 and 2013-14 growing seasons, at the Agricultural Research Station, Faculty of Agriculture, University of Bu-Ali Sina, Hamedan, Iran. The first factor consisted of chickpea and corn (forage) and the second factor was urea fertilizer levels of 0, 40, 80, 120, 160 and 200 kg/ha. Harvest operation was done on July, 2013 and 2014. SAS procedures and programs were used for analysis of variance (ANOVA) calculations.

The results showed that about all of the evaluated properties of wheat affected by pre-cropping and nitrogen fertilizer treatments. But, none of the wheat traits do not affect by pre-cropping × nitrogen fertilizer. The highest biological yield (1486 g m-2), grain yield (675 g m-2) and protein percentage (13.70%) were observed in chickpea pre-cropping treatment. Chickpea pre-cropping treatment increased wheat biological yield and grain yield and protein percentage about 17, 21 and 18 percent in comparison to corn pre-cropping treatment. Pay attention to the improved physicochemical conditions of the soil after cropping legumes such as chickpea, it is normal to improve the growth and yield characteristics of the next crop (in this study, wheat). Among the nitrogen fertilizer levels the lowest wheat biological yield and grain yield and protein percentage (about 1102 and 417 g m-2 and 11.06%, respectively) was achieved at 0 kg ha-1 N fertilizer consumption. Also, the highest wheat biological yield and grain yield and protein percentage (about 1544 and 775 g m-2 and 13.24%, respectively) was observed at 200 kg ha-1 N fertilizer consumption, but it had not significant difference with 160 kg/ha treatment. One of the most well-known effects of nitrogen fertilizers is to increase the crops properties of growth and yield. The highest nitrogen use efficiency was observed at chickpea pre-cropping and lowest level of fertilizer application. In this study, wheat growth and yield characteristics such as plant height, chlorophyll index, grain yield components, biological and grain yield, harvest index, and percentage of grain protein increased due to urea application.

It seems that in the wheat farming, legumes pre-cropping such as chickpea pre-cropping is a good solution to reduce the use of nitrogen fertilizers and to contribute to environmental health. Also, attention to optimum fertilizer levels and non-overuse of fertilizers will contribute to agricultural sustainability.

Plants are exposed to drought stress in field conditions. The occurrence of these droughts has imposed a very harmful effect on the agricultural and economic sectors of the country. Response of plants to water stress depends on the type, intensity, and duration of stress, plant species and the stage of stress occurrence. Investigate has shown that water stress before the tillering stage reduces the number of fertile tillers, stress at the flower inoculation stage reduces the weight and number of seeds and causes cluster sterility, and moisture stress during the grain filling period produces wrinkled seeds. The study aimed was to investigate the effect of different water stress conditions on yield, harvest index and sterility at the end of the cluster in wheat genotypes.

To analyze the effects of three different humidity regimes on yield, yield component and apical sterility of wheat, three different experiments were carried out in randomized completey block designs with three replications. The three different humidity regimes included normal conditions (without stress), water-stress at the meiosis stage and continuous water stress (30% of Field Capacity). Ten different wheat genotypes including Alvand, Roshan, Back cross Roshan, Ehdaei 81، Ehdaei 82، Ehdaei 79, Oxley، ChineseSpring، DN11 and Line 604 were evaluated in this experiment.

Results indicated that the responses of the genotypes to the water-stress condition were different. Analysis of variance showed highly significant variation for most of the characters under study. Both stress conditions, either meiosis stress or continuous stress, reduced all the characters of genotypes compared with non-stress conditions. Among the genotypes under study, Oxley indicated the highest amount of yield in both the meiosis stage and continuous water-stress conditions. On the other side, Line 604 showed the highest number of seeds and lowest sterile florets at both meiosis stage and continuous water-stress conditions. The highest rate of apical sterility in water-stress at meiosis stage and 30% of field capacity in Alvand genotype was observed.

Results showed that drought stress in all types of stress reduced the evaluated traits. Due to stress the number of sterile florets increased and yield decreased. Stress in the meiotic stage had a significant effect on increasing the apical sterility and total Sterility, and stress of 30% of field capacity was effective in reducing grain yield and harvest index and increasing the number of the sterile claw in wheat genotypes.

Water deficit stress is one of the most common abiotic stresses that reduce the growth, and development, and yield of crops such as oilseed rape. The Utilization of micronutrients in oilseed crops is one of the most valuable and practical approaches for improving grain yield and plant tolerance under drought stress conditions. Accordingly, this study aimed to investigate the effect of foliar application of molybdenum oxide nanoparticles on the physiological and agronomic characteristics of winter oilseed rape under the end season drought stress.

To investigate the effect of molybdenum oxide nanoparticles on the physiological and yield characteristics of oilseed rape under the end season drought stress, a split-plot experiment based on randomized complete block design (RCBD) was conducted with three replications at the research farm station of University of Mohaghegh Ardabili in 2018-2019. The experimental factors were irrigation (regular irrigation and omitting irrigation at the flowering stage) as main plots and molybdenum oxide nanoparticles foliar application ((0 (control), 25 and 50 mg/L) as sub-plots. The measured traits include the chlorophyll index, relative water content (RWC), electrical conductivity (EC), malondialdehyde (MDA) content, plant height, number of branches, number of pods per plant, number of grains per pod, 1000-grain weight, grain yield, oil percentage, and oil yield.

The results showed that the drought stress during the flowering stage significantly decreased the chlorophyll index, leaf relative water content and increased the electrolyte leakage and MDA content in the leaves, which resulted in a significant decrement of the yield and yield components of oilseed rape. Under the end season drought stress conditions, the foliar application of 25 and 50 mg/L molybdenum oxide nanoparticles significantly increased the grain yield and yield components of oilseed rape compared to the control treatment, mainly through improving the chlorophyll index and leaf relative water content and decreasing the membrane lipid peroxidation. Under the end season drought stress conditions, foliar spraying with 25 mg/L molybdenum oxide nanoparticles caused about 31.6 percent increase in the number of pods per plant, 10.09 percent in 1000-grain weight, 28.37 percent in grain yield, and 27.71 percent in oil yield of oilseed rape as compared to no spraying treatment. Under regular irrigation conditions, the highest plant height, number of branches, and number of pods per plant were obtained with foliar application of 25 mg/L of molybdenum oxide nanoparticles.

The results showed that the irrigation omitting at the flowering stage (the end season drought stress) negatively affected the growth and yield of winter oilseed rape. The foliar spraying of oilseed rap plants with molybdenum oxide nanoparticles had positive and significant effects on the physiological and agronomic traits of oilseed rape under favorable and unfavorable environmental conditions. So that, foliar spraying improved the grain yield and oil yield and reduced the harmful effects of drought stress. In general, the foliar application of 25 mg/L molybdenum oxide nanoparticles had a positive and significant effect, on the physiological and agronomical characteristics of oilseed rape, and can be used to reduce the destructive effects of drought stress and improve the grain and oil yield of this plant.

Canola (Brassica napus L.) is one of the most important oilseed plants. It is the third largest sources of oil and meal in the world. While most of the edible oil needed by the country is supplied from abroad, this crop with proper performance and adaptation to different climatic regions can play an important role in increasing oil production and required meal by the country. The potential production of grain yield and oil in canola is affected by environmental conditions and crop management. Therefore, understanding the relationship between plant production and these variables seems to be necessary to achieve sustainable yield. This study was conducted to quantify the relationships between climatic variables and management factors with plant biodiversity and canola grain yield in Gorgan fields.

This study was conducted as a survey in 58 canola fields in Gorgan County, during 2015-2016 crop year. Management data of each field collected by questionnaire and through face- to- face interview with farmers. This data included agricultural history, type of crop rotation, amount of chemical fertilizers and pesticides, type of tillage tools, amount of applied seed, spraying tools, snowing tools and other information about farmers. Also, grain yield of fields was recorded. In continue, the required meteorological information for this study, were prepared from the meteorological office of Golestan Province. The studied climatic variables were annual precipitation, minimum temperature, maximum temperature and average annual temperature. The collected data was then prepared in Excel. In the next step, in order to determine the relationship between yield and plant biodiversity with climatic and management factors, we used the analysis of RDA and Canoco software ver. 4.5.

The results showed that management factors such as farmer's history, fertilizer application, phosphorus fertilizer consumption, cultivar type (Hayola), potassium fertilizer, nitrogen fertilizer, tillage with disc and manure fertilizer application had the important impact on grain yield. Because, these factors had the closer angle with the canola yield vector. But, some factors such as burning the residue of previous crop, manual fertilization, using RGS cultivar, manually sowing and tillage with a moldboard plough had the opposite effect on canola yield. Among the climatic factors, the annual precipitation was the most important climatic factor and affected on grain yield, while other factors such as average, maximum and minimum temperatures had less effects. The biodiversity indices such as Shannon-Wiener, Simpson and reverse Simpson were calculated as 0.9-2.2, 0.11-0.46 and 2.1-4.9, respectively. According to Canoco software output, annual rainfall variable had a positive effect on plant biodiversity indices in canola fields.

In general, based on the results obtained, with the optimal use of nitrogen fertilizer, appropriate pest management, optimal seed consumption, selection of appropriate sowing date, selection of suitable cultivars and seed infection, canola yield can be increased in fields of Gorgan County.

Leaf chlorophyll content in plants indicates their health, physiological status, their photosynthetic activity and nitrogen content. Monitoring pigment content of crop tissues helps identification of plant nutrition and environmenta stresses before serious damages to crop and yield. This study was conducted to estimate the leaf pigments content of winter wheat (Triticum aestivum L.) as one of the most important crops using Landsat 8 satellite data and statistical models in Shahrekord county, Chaharmahal and Bakhtiari province in 2017.

For this purpose, eight fields under winter wheat cultivation with an area between 10 to 60 hectares throughout Shahrekord county were considered. The location of 120 sampling units was randomly and determined in fields using ground positioning system (GPS). The sampling units were 30 × 30 m squares according to Landsat pixels. In each unit 5 plots (0.5 × 0.5 m) were considered, four plots in the corners and one in the center of the unit. Crop sampling and passing over of satellite were synchoronous. The samples were transferred to the laboratory and their chlorophyll and carotenoid content were measured. The corresponded Landsat 8 data were processed and and vegetation indices were calculated. Simple and multiple stepwise linear regression methods were used to obtain models for estimating chlorophylls and carotenoids content of wheat leaves.

The results showed that among the selected indices, PSRI index for estimating chlorophyll a content (R2 = 0.408 and RMSE= 8.38 µg.cm-2), chlorophyll b (R2 = 0.400 and RMSE= 3.69 µg.cm-2) and total chlorophyll (R2 = 0.500 and RMSE= 10.82 µg.cm-2), CRI index (R2 = 0.480 and RMSE= 2.92 µg.cm-2) for estimating leaf carotenoid content and SIPI index (R2 = 0.603 and RMSE = 0.17 µg.cm-2) for estimating carotenoid to chlorophyll a ratio had the best performance in simple linear regression. Models based on multiple stepwise linear regression estimated chlorophyll a content with R2 = 0.557 and RMSE = 7.73 µg.cm-2, chlorophyll b with R2 = 0.471 and RMSE = 3.69 µg.cm-2, total chlorophyll with R2 = 0.611 and RMSE = 10.10 µg.cm-2, carotenoids with R2 = 0.50 and RMSE = 2.01 µg.cm-2 and carotenoid to chlorophyll a ratio with R2 = 0.756 and RMSE = 0.12 µg.cm-2. PSRI and CVI indices for estimating chlorophyll a and total chlorophyll content, PSRI index for estimating chlorophyll b content, CRI and TCI / OSAVI indices for estimating carotenoid content and SIPI, GNDVI, EVI, CIgreen, TCARI and OSAVI for carotenoid to chlorophyll a ratio of wheat leaf were the most effective indices in a stepwise multiple linear regression models. In our study, estimation of chlorophyll a, total, carotenoid content and carotenoid to chlorophyll a ratio based on stepwise multiple linear regression was superior to simple linear regression models. Estimation of chlorophyll b content was the same in both methods.

The use of vegetation indices derived from Landsat 8 data makes it possible to estimate the content of wheat leaf pigments with relatively good results in the study area. Such information is important for farmers to initially monitor the quality and quantity of production and leads to a practical and efficient planning in the fertilization process.

One of the strategies to increase the yield per unit area is to use suitable cultivars that are compatible with the climatic conditions of each region at the appropriate planting density, so that there is minimal competition between plants. Determining the appropriate crop density for rapeseed cultivars is very important and plays a decisive role in achieving the desired yield. Planting the crop for each plant and cultivar should be done in a density where the plant is well emerge, establish and in each stage of growth, has enough space to maximize the use of environmental factors and not face unfavorable conditions as much as possible.

This factorial experiment was conducted in a randomized complete block design in research farm of Gharakhil Agricultural Research Center, Ghaemshahr in 2017-2018. Treatments included: densities of 42, 66, 88, 114 and 133 plants m-2 and four rapeseed cultivars including: Hyola 401, Agamax, Hyola 4815 and Trapper which were performed in three replications. The evaluated traits included growth indices such as total dry matter content, leaf area index, crop growth rate, relative growth rate and net photosynthesis rate as well as yield.

The results showed that the interaction effect of cultivar and plant density was significantly different only for total dry matter and leaf area index. Maximum amount of total dry matter (910 g m-2) and leaf area index (3.53) was observed in Hayola 401 cultivar and density of 88 plants m-2 and minimum amount of total dry matter (393 g m-2) and leaf area index (2.26) was observed in Trapper cultivar at a density of 42 plants m-2. According to the results, the only simple effect of density was significant on crop growth rate, relative growth rate and net photosynthesis rate, according to which the highest crop growth rate with an average of 11.36 g m-2 d-1 was related to the density of 88 plants m-2 and the lowest one was obtained with an average of 5.91 g m-2 d-1 from a density of 42 plants m-2. Also, the maximum relative growth rate and net photosynthesis rate with an average of 0.0580 g g-1 d-1 and 3.49 g m-2 were obtained at a density of 88 plants m-2, respectively, and their minimum ones with an average of 0.0530 g g-1 d-1 and 2.99 g m-2 was seen from the density of 42 plants m-2. The highest grain yield with an average of 7031.8 kg ha-1 was related to Hayola 401 cultivar in a density of 88 plants m-2.

With increasing density of 42 plants m-2, dry matter production and leaf area increased; when the highest amount of dry matter and leaf area index in cultivar Hayola 401 in density of 88 plants m-2 had the best results and the highest rate of crop growth rate, relative growth rate and net photosynthesis rate were obtained at density of 88 plants m-2. Therefore, in low densities, due to the lack of complete canopy closure and low surface for radiation absorbance (leaves), dry matter production had decreased, while with increasing density more than 88 plants.m-2 due to increase intra specific competition, dry matter production and leaf area index decreased. Therefore, according to the results, planting cultivars Hayola 401 at a density of 88 plants m-2 is recommended to achieve high yields in the climate of Mazandaran.

Faba bean (Vicia faba L.) is one of the most important legumes for its seed high protein content and nutritional value, and is still considered to have great potential as rainfed crop. Faba bean is a very valuable legume crop that contributes to the sustainability of cropping systems through its ability of biological N2 fixation, diversification of cropping systems leading to decreased disease, pest and weed. The decrease in area under cultivation in Iran, mainly because of high yield instability. This can be attributed to biotic and abiotic stresses Faba bean yield is strongly influenced by environments and breeders often determine the stability of high yield genotypes across environments before recommending a stable cultivar for release. The purpose of this study is the distinguishing the superior genotypes in terms of yield and yield stability in 15 selected faba bean lines from preliminary yield test.

15 selected lines obtained from crosses between ICARDA lines and Iranian improved and landrace varieties and resulted from preliminary yield test of 2013-2014 cropping season, along with control cultivar Barekat, Saraziri, Zereshki and Baluchi were evaluated in a Gorgan, Dezful, Borojerd and Iranshar at two cropping seasons (2015-2017) in a randomized complete block design with three replications. Stability analysis were performed with Eberhart-Russell analysis of variance, Shukla's variance (2i), Wrick equivalence (Wi), environmental variance (S2i), coefficient of environment variation (CVi), coefficient of determination (R2), Finlay and Wilkinson regression coefficient (bi), Lin and Binns superiority index (Pi), yield stability index (YSi) and nonparametric methods such as , , Z1, Z2 and TOP and mean and standard deviation of rank.

Combined analysis of variance was performed after Bartlett test and not significant of it and assurance of uniformity of experimental errors. Combined analysis of variance indicated a significant effect of genotype, environment and genotype × environment interaction on seed yield. Based on Wrick equivalence, Shukla variance and RMSE indices, genotypes 5, 13, 14 and 15 were more stable. Genotype 9 had lowest environmental variance and coefficient of environmental variation and was stable than the other genotypes. genotypes 9 and 11 had the highest R2and the lowest deviation from regression. The coefficient of regression in genotypes 6, 9 and 16 were lower than one and their seed yield were higher than total average seed yield and therefore were the stable genotypes. Genotypes were stable genotypes. According to the priority index in all of environments and favourable environments, genotypes 11, 12, 14 and 15 were adapted to the unpredictable high yielding environments(1, 3, 5 and 7), while 6, 9, 14, 16 and 12 were adapted to low yielding environments(2, 4, 6 and 8).Simultaneous analysis based on seed yield and stability (YSi) indicated genotypes 6, 7, 9, 11, 12, 13, 14, 15 and 16 were as stable genotypes. Based on Top statistic, genotypes 12 and 14 and based on and , genotype 11 were stable than the other genotypes. Results of Selection index of ideal genotype (SIIG) method, Based on all non-parametric methods, showed that 14 and 15 genotypes whit 3478 and 3439 kgha-1 grain yield were the most stable genotypes. ConclusionBased on all indices, genotypes 9 and 11 were the most stable genotype in terms of seed yield and could be considered a good breeding material stock in any future breeding program.