mohammadreza karim

Rice is one of the most important crops in Asian countries, which is cultivated in more than half of the continent's agricultural lands. Environmental conditions are different and uncontrollable even in different parts of an area, so the response of rice cultivars to these conditions will be different. Therefore, it is necessary to perform performance comparison experiments to achieve high quality, quantity, consistency and stability in different regions. More than 50 percent of human food is supplied from cereals, and rice is a cereal that has a high crop after wheat, but more than wheat and others in terms of energy production per hectare Cereals are important. By using the GGE biplot method, by using multivariate methods, in addition to proper data analysis, the work facilitates the interpretation of the results. The aim of this study was to evaluate the stability of the lakes by using GGE biplot analysis and selecting and introducing superior lanes for stability and response in underwater stress conditions and flooding.

In this experiment, the eight lines with the control cultivar of the region and IR29 cultivar during 2014 and 2015 with the desirable qualitative and qualitative characteristics and suitable growth period in a completely randomized block design with three replications in two regions of Gonbad Kavous and Ali-Abad were cultivated. Ten plants of 15 cultivated plants were randomly selected and separated from the soil at a depth of 50 cm. After removing the bushes from the soil using the shovelomics method, the plants were first immersed in water for seven days. Then the root and part of the air organs were separated. To record the root characteristics, each root of the plant is separated and the number of roots is less than 5 cm, the number of roots is 7-6 cm, the number of roots between 20-8 cm, the number of roots 21-30 cm and the number of roots greater than 30 cm, root volume and root dry weight were measured. Using the aerial parts, related traits such as panicle number, plant height, stem weight, straw weight, panicle length, number of filled grains, weight of grains and cluster number were recorded.

The results of analysis of variance showed that the difference between locations for days to days of traits, number of roots, total length of roots, root number between 7 to 20 cm, stem weight, panicle weight, root dry weight, straw weight and seed number Poke was significant, and the difference between years was significant for number of pancakes, root number was significant. Comparison of mean of studied sites and years showed that grain yield per hectare had no significant difference, but the mean comparison of this trait in terms of waterlogging and stress conditions indicated that flooding conditions had a higher yield than tension. Separation of the interaction of location × planting time × irrigation conditions with different cultivars by biplot method showed that the cultivar 87.5.103 in all states related to Aliabad city had the highest yield. In irrigation stress conditions, IR55411, IR70360, 87.5.21, IR66424 and 87.110 lines had lower yields, but in terms of flooding, IR55411, IR70360, 87.5.21, IR66424 and 87.110 lines had the highest yield, respectively. In both cases, all of the cultivars had a higher yield than IR-29

Separation of the interaction of location × planting time × irrigation conditions with different cultivars by biplot showed that cultivar 87.5.103 in all states related to Aliabad city has the highest performance. In general, the cultivar 87.5.103 among all cultivars and the floodplain dome in the first year was the best environment for all the environments in terms of day.

Rice is an important crop that is considered a staple meal for 2.7 billion people worldwide. Therefore, the demand for it will increase with the increase of population. Environmental constraints always pose a serious threat to crop production, including rice. Drought is one of the most important challenges that limits the production of high-yielding cultivars in arid and rainfed areas. Global warming has also become a factor in limiting rice production in rain-dependent areas. Therefore, researchers are looking for a way to stabilize rice production in arid regions. In this study, informative markers related to the desired agronomic traits were identified in 59 rice genotypes using microsatellite marking system.

In order to evaluate the tolerance of rice genotypes to drought stress and to identify tolerant and sensitive genotypes, 59 genotypes received from the National Rice Research Institute and the International Rice Research Institute in a randomized complete block design with three replications in two separate conditions, without Stress (flood) and drought stress were performed in a research farm located in Aliabad Katoul city in 2013. In both conditions (normal and drought stress), the genotypes were planted in five rows of 25 × 25 cm in rows one meter long. Thirty days after planting in the nursery, healthy and strong seedlings were transferred to the main land. The required agronomic operations were carried out equally during the growth and development period of the plants under stress and normal conditions and only in terms of irrigation of the experimental field in both flood and stress environments, until the tillering stage of the cultivars were equally flooded. Then, to create stress, irrigation was done from 40 days after transplanting (maximum tillering stage) to the end of the growing season at 25-day intervals. Phenotypic values of grain yield and 1000-grain weight were measured under two conditions according to standard guidelines for evaluation of traits in rice. In order to investigate the relationship between agronomic traits and microsatellite markers with 59 rice genotypes out of 36 microsatellite molecular markers were performed in the Plant Breeding and Genetics Laboratory of Gonbad Kavous University, Faculty of Agriculture and Natural Resources. Young leaves of 21-day-old seedlings were extracted in four-leaf stage using CTAB method. Touchdown PCR reaction was studied and evaluated randomly using 36 microsatellite primers for 3 markers from each chromosome. To separate PCR products, 6% polyacrylamide gel electrophoresis was used and to reveal the banding pattern, silver nitrate staining method was used. The content of polymorphic information was calculated. The relationship between molecular data and traits of studied rice genotypes was investigated using multiple regression. Thus, each quantitative trait was considered as a dependent variable and microsatellite markers were considered as independent variables.

The average content of polymorphic corrections (PIC) was estimated to be 0.58, which showed RM 5647 with 0.81 the highest and RM 6022 with 0.32 the lowest polymorphism (PIC). The results of stepwise regression analysis showed that a total of 90 markers for normal conditions and 69 markers for drought stress conditions for morphological traits were identified. Under normal conditions, the number of spikes and the number of days to flowering with 9 markers and under drought stress, the weight of the cluster with 9 markers showed the most positive markers. The most explanation for variation in normal conditions is related to the total number of grains (0.83) by gene loci RM6324-E, RM5652-E, RM5761-D, RM6179-F, RM549-B, RM462-B, RM7420-D Explained. In drought stress conditions, the most explanation for variation related to panicle weight (0.70) by gene loci RM519-D, RM7545-A, RM6179-E, RM7118-G, RM3525-B, RM5761-B, RM38-C, RM7091-A, RM5647-B explained.

The results showed that some markers are associated with more than one trait, which indicates that these traits are very closely related to each other or may be influenced by multi-effect genes. To understand this, it is necessary to develop transgressive generations and linkage.

In order to evaluate the effect of drought stress on yield and the other related traits, 14 rice genotypes (including five varieties of landrace and introduced varieties) in a randomized complete block design with three replications in two environments without stress (flooding) and drought stress in the field Research located in Aliabad (under the supervision of Gonbad Kavous University) was studied. Irrigation of experimental farm in both the flood and drought were flooded until maximum tillering stage. Irrigation was performed every 25 days until the end of the season from 40 days after maximum Tillerin). Analysis of variance showed significant differences among genotypes for all traits in both conditions. The average yield of the genotypes in the normal and stress conditions lR83752-BB-12-3 and was Sepedroud. Panicle weight (0.85**) under stress (flooding) and root volume (0.98**) in drought stress conditions, the highest positive correlation with grain yield were Significant. Path analysis results showed that different traits were involved in justifying grain yield under non-stress and drought stress conditions, so that in non-stress condition, number of panicle and in drought condition, number of filled grain per panicle had the highest direct and positive effect on grain yield. In grouping cultivars based on cluster analysis using ward method, cultivars were divided into three groups under normal conditions and stress. The results of cluster analysis showed that Pegaso, IR83752-B-B-12-3 and Sepidrood cultivars, which had more volume, fresh weight and root dry weight than other cultivars, were in the drought tolerant group.