فصلنامه علوم زراعی ایران
سال بیست و چهارم شماره 4 (پیاپی 96، زمستان 1401)

To assess the productivity potential of dual-purpose (grain-forage) sorghum promising lines at different harvesting times, a field experiment was carried-out using randomized complete block design with three replications in six locations (Karaj, Mashhad, Isfahan, Birjand, Shiraz, and Gorgan) Iran, during 2017 and 2018 growing seasons. Morphological traits and yield of seven dual purpose sorghum promising lines (KDFGS4, KDFGS6, KDFGS9, KDFGS10, KDFGS16, MDFGS1, and MDFGS2) were evaluated at four harvest stages (milk, soft dough, hard dough, and physiological maturity). The results showed that the lowest silage forage yield and the highest dry forage yield in all sorghum promising lines were obtained at the physiological maturity stage. The highest dry forage (34.32 ton.ha-1) and grain yield (7.39 ton.ha-1) were recorded in Shiraz and Isfahan.  The lowest forage and grain yield were produced in Birjand and Gorgan, respectively. The highest (6.67 ton.ha-1) and lowest (5.04 ton.ha-1) grain yield (obtained from KDFGS6 and KDFGS16 lines, respectively. The highest silage forage yied and dry forage yield, the tallest plant height, and the shortest panicle length belonged MDFGS1 line. Considering the suitable dry matter content for silage forage production, the soft dough stage was identified as appropriate stage to harvest sorghum forage. The highest grain yield stability belonged to MDFGS2, KDFGS6, and KDFGS10 lines, repectively. While, the highest forage yield stability belonged to KDFGS9, KDFGS6, and MDFGS1 lines, respectively. Based on the results of this study and considering the yield and yield stability, KDFGS6 line was identified as the superior dual-purpose (grain-forage) sorghum genotype, and MDFGS1 promising line was more suitable for forage production.

Shortage of irrigation water is the most important limiting factor in sugar beet production, therefore, winter sowing can be a suitable strategy to increase water produvtivity and production of this crop. For this purpose, 11 sugar beet early cultivars were sown in the first half of February and were studied on two different harvest dates (early and late July) at Moghan Agricultural Research Station (Iran) during three cropping seasons (2019, 2020 and 2021). Since bolting percentage in all studied sugare beet cultivars was zero, therefore, this trait was not included in the analyses. Combined analysis of variance showed that the effects of year and cultivar were significant (P≤0.01) on all the studied traits: root yield, sugar content, Na+, K+, alpha amino N, sugar yield, molasses sugar content, white sugar content, white sugar yield and extraction coefficient of sugar. The harvest time and year interaction effect was significant (P≤0.01) on all traits. Cultivar and year interaction had significant effect on all traits except root yield and molasses sugar content. Cultivar and harvest time interaction effect was only significant on K+ and white sugar yield. Mean comparisons indicated that the highest white sugar yield obtained in the second (12.60 ton.ha-1) and first (12.18 ton.ha-1) harvest time of 2021cropping season, respectively. Cv. FDIR19B3021 (14.38 ton.ha-1), cv. Dravus (14.26 ton.ha-1) and cv. SVZB2019 (14.18 ton.ha-1) had the highest white sugar yield in 2021 cropping season, respectively. Cv. FDIR19B3021 (10 ton.ha-1) and cv. Dravus (9.70 ton.ha-1) had the highest white sugar yield in the second harvest time, respectively. Considering the results of this experiment, cv. FDIR19B3021 and cv. Dravus can be recommended for winter sowing in Moghan region should the crop is harvested in late July.

To evaluate the effect of autumn sowing date on seed yield of sunflower cultivars, a field experiment was carried out as strip plot arrangement in randomized complete block design with three replications in safiabad agricultural and natural resources research and education center of Dezful, Iran during two growing seasons (201718 and 2018-19). Seven sowing dates (6th Sep., 23rd Sep., 7th Oct., 22nd Oct., 6th Nov., 21st Nov. and 6th Dec.) were assigned to vertical strips and five sunflower cultivars (Azargol, Barzegar, Progress, Farokh and Lakomka) were randomized in horizontal strips. Mean comparison of sowing date and cultivar interaction showed that the highest growth duration (204 days) belonged to sowing date of 21st Nov. and cv. Progress. The lowest growth duration (118 days) was for cv. Farokh in sowing date of 6th Sep. Delay in sowing date led to decrease in head diameter and thousand seed weight of all sunflower cultivars. Delaying in the sowing date also led to shorter plant height. The highest (42.8%) and the lowest (37.7%) seed oil content was observed in the first (6th Sep.) and the last (6th Dec.) sowing dates, respectively. Cv. Azargol (41.9%) and cv. Farokh (38%) had the highest and the lowest seed oil content. Mean comparisons of sowing date and cultivar showed that the highest seed yield (2985 kg.ha-1) belonged to the first sowing date (6th Sep.) and cv. Progress. The lowest seed yield
(232 kg.ha-1) obtained from cv. Lakomka in 6th Dec. sowing date. The results of this experiment showed that the period of 6th until 23rd Sep. is suitable sowing date window for autuom sowing sunflower in the north of Khuzestan province.

Knowledge of genes action on important traits and their breeding value is necessary to achieve high yielding cultivars in food crops. Molecular markers has eliminated the need for knowing the pedigree of genotypes for estimating Kiniship matrix required to estimate breeding values of taits of interest. In this research, 97 genotypes of maize were evaluated for 17 different agronomic triats using randomized complete block design with six replications at the faculty of agriculture of Urmia University, Urmia, Iran, in 2015. The molecular profile of maize genotypes was evaluated using 16 ISSR primers, and 78 polymorphic bands were amplified. Primers UBC825 and UBC811 produced the highest and lowest number of polymorphic bands, respectively. Breeding value of traits was calculated by best linear unbiased prediction (BLUP) using linear mixed model (MLM) and Kinship matrix based on molecular data. Considering estimated breeding values for sum traits, genotypes P10L5, P16L6 Kahia, 14*89, OH43/1-42 and P10L7 had the highest rank. Genotype 163*/6/15, the only line of sixth group, had positive and high breeding value for leaf area ratio, and negative and low breeding value for trait of grain yield plant-1. Narrow sense heritability of traits was calculated based on beeding values. The highest narrow sense heritability belonged to tassel emergence date. The high narrow sense heritability facilitates selection for desirable trait based on its phenotypic expression. The positive breeding value indicates higher likelyhood of inheritance of desirable traits in next generation in maize breeding programs.

To evaluate the genetic diversity in quinoa genotypes for future studies, 60 imported quinoa genotypes were studied using microsatellite markers (SSR) at the faculty of agricultural sciences, University of Guilan, Rasht, Iran, in 2022. The results of the phenotypic evaluation of the quinoa genotypes showed that there was a relatively high diversity among them. Among the studied traits, seed yield plant-1 (42.8) and days to seed dough stage (8.14) had the highest and lowest phenotypic coefficient of variation, respectively. Evaluating the molecular diversity of genotypes using 40 microsatellite markers produced 136 polymorphic bands, and the average number of effective alleles (1.81), polymorphic information content (0.60), Shannon's index (0.54) and Nei’s genetic diversity (0.44), confirmed the existence of high diversity among the quinoa genotypes. The markers KAAT027, KAAT036, KAAT040, KCAA014, KGA042, KGA055 and KGA059 with five polymorphic alleles had the highest number of polymorphic alleles among the used markers in this experiment. The average number of effective alleles of microsatellite markers in the studied quinoa genotypes was 1.81 alleles, and markers KAAT027 and KAAT006 with 3.75 and 1.08 alleles showed the highest and lowest number of alleles, respectively. Cluster analysis using UPGMA method grouped 60 quinoa genotypes into two subpopulations with 38 and 22 genotypes. Since one of the important criteria to choose suitable and useful markers is the number of effective alleles, therefore, markers with more effective alleles such as KAAT027, KAAT036 and KAAT040 (all with more than three effective alleles) can be used to investigate the genetic diversity of quinoa genotypes in the future researches.

The large number and high diversity of genetic resource collections usually affect the accuracy of assessment and exploitation of the potential of these resources. The core collection provides the solution for the challenges of genetic resources manegement. This study aimed to develop the core collection of native barley germplasm of Iran. The germplasm collection of barley germplasm (Hordeum vulgare) in the National Plant Gene Bank of Iran includes about 3150 native barley accessions with high genetic diversity. The core collection of barley germplasm was developed in five main steps. For this purpose, from 2011 to 2019, the traits of native barley accesions of Iran were evaluated. Then, by using the data of evaluated traits and collecting site, the collection accessions were grouped based on their similarityies. The strategy used for the grouping was evaluated based on a hierarchical structure defined based on the areas of collection and qualitative morphological traits. Variation in other morphological traits in different groups obtained from cluster analysis was also studied. By grouping similar accessions and selecting 10% of each group, the level of allele diversity increased in the core collection. The barley core collection was developed with 333 accessions which accouned for more than 10% of the main collection. A comparison of Shannon index values ​​in the core collection with the main collection showed that the core collection had higher diversity for most of the qualitative traits of the index. The results demonstrated that the selection of right accessions for the core collection and its efficiency in preserving the diversity of the germplasm of main collection in a smaller and more accessible collection.