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In order to estimate the drought effects on capitula characteristics and self-pollination of globe artichoke (Cynara cardunculus var. scolymus Hayek L.), the randomized complete block design was carried out with three irrigation regimes (20 %, 50 % and 80 % depletion of soil available water) and six replicates. The artichoke is mostly open-pollinated, however, after covering the buds and isolation of flowers to prevent cross pollination, 1.79 % self-pollination was observed and this amount was not affected by different irrigation regimes. In stress conditions (50 % and 80 % water depletion) as well as non-stress condition (20 % water depletion), plants with respectively one and two medium capitula and without small capitula had most relative frequencies in the population and drought stress increased these relative frequencies by reducing the number of medium and small capitula in plants. In addition, Capitula size and dry weight were significantly affected by water stress. Water shortage induced severe decrease in length and dry weight of all capitula including large, medium and small, although capitula width was less affected by water deficit and only slight decline in medium (12.5 %) and small capitula (23.7 %) was observed under severe stress condition.

Bottlenecks, including limited genetic variation and the ongoing loss of genetic diversity, have hindered the development of modern wheat cultivars., making it crucial to use genetic diversity from wild relatives to improve wheat's adaptation to abiotic stress, such as salinity. This study assessed the phenotypic and epigenetic variation of introgressed wheat lines (BC4F2) derived from hybridizing two wheat cultivars with Aegilops cylindrica (AC). This study assessed the phenotypic and epigenetic variation of 156 introgressed wheat lines (BC4F2) derived from hybridization between wheat cultivars "Chinese Spring" (CS) and "Roshan" (R) and Aegilops cylindrica (AC). These lines and their recurrent parents (total of 158) were evaluated under normal and saline field conditions for the agronomic traits and stress tolerance indices. The data were used to select the most tolerant and most sensitive lines. Then, the selected BC4F2 lines and their parents (AC, CS, and R) were subjected to physiological, DNA cytosine methylation, and expression analysis of HKT1;5, NHX1, and SOS1 genes under control and salt stress conditions. Agro-physiological, epigenetic, and gene expression analyses showed the significant effects of salt stress and genetic background, as well as the differential response of the BC4F2 lines to salt stress. The variations in leaf and root K, Na, and K/Na ratios, and leaf Chla, Chlb, Car, and MDA levels, unlike DPPH radical scavenging levels, between salt-tolerant and salt-sensitive BC4F2 lines under saline conditions indicated a substantial distinction in salinity tolerance responses. RT-qPCR indicated higher expression levels of NHX1 and SOS1 genes in the leaf and root tissues of tolerant lines than those of sensitive lines. Global leaf and root DNA methylation analysis revealed the significant effects of salinity on the methylation modifications and confirmed the successful introgression of the salt-tolerance epigenome from Ae. cylindrica into wheat. Exploiting the genetic diversity of wild wheat relatives is a crucial goal for increasing genetic and epigenetic variation to enhance plant adaptation to salt stress. [ABSTRACT FROM AUTHOR]

A doubled haploid (DH) population derived from a cross between the Japanese cultivar 'Fukuho-kumogi' and the Israeli wheat line 'Oligoculm' was used to map genome regions involved in the expression of grain yield, yield components, and spike features in wheat (Triticum aestivum L). A total of 371 markers (RAPD, SSR, RFLP, AFLP, and two morphological traits) were used to construct the linkage map that covered 4190 cM of wheat genome including 28 linkage groups. The results of composite interval mapping for all studied traits showed that some of the quantitative trait loci (QTL) were stable over experiments conducted in 2004 and 2005. The major QTL located in the Hair-Xpsp2999 interval on chromosome 1A controlled the expression of grains/spike ([R.sup.2] = 12.9% in 2004 and 22.4% in 2005), grain weight/spike ([R.sup.2] = 21.4% in 2004 and 15.8% in 2005), and spike number ([R.sup.2] = 15.6% in 2004 and 5.4% in 2005). The QTL for grain yield located on chromosomes 6A, 6B, and 6D totally accounted for 27.2% and 31.7% of total variation in this trait in 2004 and 2005, respectively. Alleles inherited from 'Oligoculm' increased the length of spikes and had decreasing effects on spike number. According to the data obtained in 2005, locus Xgwm261 was associated with a highly significant spike length QTL ([R.sup.2] = 42.33%) and also the major QTL for spikelet compactness ([R.sup.2] = 26.1%). Key words: doubled haploid, grain yield, QTL, spike features, wheat. Une population de lignees haploides doublees (DH) derivees d'un croisement entre le cultivar japonais 'Fukuhokumogi' et la lignee israelienne 'Oligoculm' a ete employee pour identifier des regions du genome qui sont impliquees dans l'expression du rendement en grains, des composantes du rendement ainsi que des caracteristiques de l'epi chez le ble (Triticum aestivum L.). Au total, 371 marqueurs (RAPD, SSR, RFLP, AFLP et deux caracteres morphologiques) ont ete utilises pour produire une carte genetique s'etendant sur 4190 cM repartis sur 28 groupes de liaison. Les resultats d'une analyse de cartographie d'intervalles composite pour tous les caracteres a l'etude a montre que certains des locus de caracteres quantitatifs (QTL) etaient stables pour les experiences realisees en 2004 et 2005. Le QTL majeur situe dans l'intervalle Hair- Xpsp2999 sur le chromosome 1A controlait le nombre de grains/epi ([R.sup.2] = 12,9 % en 2004 et 22,4 % en 2005), le poids en grains/epi ([R.sup.2] = 21,4 % en 2004 et 15,8 % en 2005), ainsi que le nombre d'epis ([R.sup.2] = 15,6 % en 2004 et 5,4 % en 2005). Les QTL pour le rendement en grains qui sont situes sur les chromosomes 6A, 6B et 6D expliquaient conjointement 27,2 % et 31,7 % de la variation pour ce caractere en 2004 et en 2005 respectivement. Les alleles du parent 'Oligoculm' contribuaient a augmenter la longueur des epis et a decroitre le nombre d'epis. Sur la base des resultats obtenus en 2005, le locus Xgwm261 a ete associe avec un QTL tres hautement significatif ([R.sup.2] = 42,33 %) pour la longueur des epis et avec un QTL majeur pour la densite des epillets ([R.sup.2] = 26,1 %) Mots-cles : haploides doubles, rendement en grains, QTL, caracteristiques de l'epi, ble. [Traduit par la Redaction], Introduction The progress in genetic improvement over the last century was based mainly on the use of single genes with relatively clear-cut effects on the phenotype (Newbury 2003). As agronomic [...]

Water deficit is the most limiting factor for seed yield of crop species in the arid and semi-arid regions. Due to increasing limitation of fresh water resources and importance of safflower (Carthamus tinctorius L.) as a significant oilseed crop in Iran, it is necessary to evaluate physiological responses of drought tolerance and its association with seed yield of this crop in water stress condition. In this study, 21 safflower genotypes were planted by hand in the field under water stress and non-stress conditions in a randomized complete block design with two replications during 2 years (2016–17). The results indicated that water deficit stress significantly reduced relative water content (RWC), chlorophyll a (Chl-a) and chlorophyll b (Chl-b) concentrations and seed yield, but increased ascorbate peroxidase (APX) and peroxidase (POX) activities and leaf proline concentration. Significant differences were observed among the genotypes for all studied traits except Chl-b concentration. Genotypes were discriminated according to their response to drought using stress tolerance index (STI). Drought tolerant genotypes displayed a higher capability for accumulation of proline in association with maintaining RWC, antioxidant enzymes activity and higher seed yield, compared to the drought sensitive genotypes. Presented results suggested that safflower genotypes with higher levels of antioxidant enzymes activity, RWC and proline accumulation are characterized by a higher STI. Therefore, these physiological traits can be employed as effective criteria for selecting safflower genotypes with more tolerance to water deficit stress. [ABSTRACT FROM AUTHOR]