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Divergent phenotypic selection was performed for flag leaf angle (FLAN) under heat stress in five F2 populations of bread wheat (Triticum aestivum L.). Direct responses for FLAN and correlated responses for grain yield per plant (GYP) and thousand kernel weight (TKW) were measured. FLAN was positively and significantly correlated with GYP and TKW under heat stress. Positive and highly significant (P0.01) responses to selection for FLAN were obtained in both directions for the five populations, which were higher in magnitude in the low direction (averaged 31.41) than those obtained in the high direction (averaged 22.0%). Selection for high FLAN produced concurrent positive and significant (P0.05) responses in GYP in only two populations, with an average of 5.17%, which was lower in magnitude than averaged correlated responses (8.24%) obtained in GYP for lower FLAN in four populations. Significant (P0.05) correlated responses to selection in TKW for higher FLAN were obtained in four populations (averaged 4.03%) and were smaller in magnitude than those obtained for lower FLAN (averaged 9.56%). Additive gene effects were found to be mainly controlling FLAN. Moderate realized heritability estimates obtained for FLAN (averaged 0.53) were similar to heritability obtained by parent-offspring regression (averaged 0.50). Bulked segregant analysis (BSA) using twelve simple sequence repeats (SSR) markers for FLAN identified three SSR markers, namely Xgwm294-2A; Xbarc113-6A and Xwmc398-6B were able to distinguish high from low bulks in at least two populations. Three bands specific for high and two specific for low FLAN were generated, that could be used in the future as markers associated with FLAN under heat stress in wheat. The information presented here could help in understanding the genetic system controlling FLAN and its relationship with grain yield under heat stress.

Divergent phenotypic selection was performed for flag leaf angle (FLAN) under heat stress in five F2 populations of bread wheat (Triticum aestivum L.). Direct responses for FLAN and correlated responses for grain yield per plant (GYP) and thousand kernel weight (TKW) were measured. FLAN was positively and significantly correlated with GYP and TKW under heat stress. Positive and highly significant (P0.01) responses to selection for FLAN were obtained in both directions for the five populations, which were higher in magnitude in the low direction (averaged 31.41) than those obtained in the high direction (averaged 22.0%). Selection for high FLAN produced concurrent positive and significant (P0.05) responses in GYP in only two populations, with an average of 5.17%, which was lower in magnitude than averaged correlated responses (8.24%) obtained in GYP for lower FLAN in four populations. Significant (P0.05) correlated responses to selection in TKW for higher FLAN were obtained in four populations (averaged 4.03%) and were smaller in magnitude than those obtained for lower FLAN (averaged 9.56%). Additive gene effects were found to be mainly controlling FLAN. Moderate realized heritability estimates obtained for FLAN (averaged 0.53) were similar to heritability obtained by parent-offspring regression (averaged 0.50). Bulked segregant analysis (BSA) using twelve simple sequence repeats (SSR) markers for FLAN identified three SSR markers, namely Xgwm294-2A; Xbarc113-6A and Xwmc398-6B were able to distinguish high from low bulks in at least two populations. Three bands specific for high and two specific for low FLAN were generated, that could be used in the future as markers associated with FLAN under heat stress in wheat. The information presented here could help in understanding the genetic system controlling FLAN and its relationship with grain yield under heat stress.

Divergent phenotypic selection was performed for flag leaf angle (FLAN) under heat stress in five F2 populations of bread wheat (Triticum aestivum L.). Direct responses for FLAN and correlated responses for grain yield per plant (GYP) and thousand kernel weight (TKW) were measured. FLAN was positively and significantly correlated with GYP and TKW under heat stress. Positive and highly significant (P0.01) responses to selection for FLAN were obtained in both directions for the five populations, which were higher in magnitude in the low direction (averaged 31.41) than those obtained in the high direction (averaged 22.0%). Selection for high FLAN produced concurrent positive and significant (P0.05) responses in GYP in only two populations, with an average of 5.17%, which was lower in magnitude than averaged correlated responses (8.24%) obtained in GYP for lower FLAN in four populations. Significant (P0.05) correlated responses to selection in TKW for higher FLAN were obtained in four populations (averaged 4.03%) and were smaller in magnitude than those obtained for lower FLAN (averaged 9.56%). Additive gene effects were found to be mainly controlling FLAN. Moderate realized heritability estimates obtained for FLAN (averaged 0.53) were similar to heritability obtained by parent-offspring regression (averaged 0.50). Bulked segregant analysis (BSA) using twelve simple sequence repeats (SSR) markers for FLAN identified three SSR markers, namely Xgwm294-2A; Xbarc113-6A and Xwmc398-6B were able to distinguish high from low bulks in at least two populations. Three bands specific for high and two specific for low FLAN were generated, that could be used in the future as markers associated with FLAN under heat stress in wheat. The information presented here could help in understanding the genetic system controlling FLAN and its relationship with grain yield under heat stress.

Ten bread wheat genotypes (Triticum aestivum L.) were evaluated for heat tolerance under normal and late sowing dates during 2014/2015 and 2015/2016 seasons. Four agronomic traits, i.e. grain yield per plant (GYP), 1000-kernel weight (TKW), Spike length (SL) and plant height (PH) were evaluated. The genetic diversity was assessed among genotypes based on phenotypic data and thirteen simple sequence repeats (SSR) markers, representatives of nine wheat chromosomes. Heat stress under the late sowing date was quite strong resulting in 30.4, 14.6, 14.7 and 28.8% average reduction for GYP, TKW, SL and PH, respectively. GYP showed a negative and significant correlation (r= -0.66, P0.05) with heat susceptibility index (HSI) under heat stress. By using 13 SSR markers, a total of 125 DNA fragments were generated, with an average of 9.6 bands per marker. The level of polymorphism (%P) ranged from 25% for the marker Xgwm497-1A to 85.7% for Xwmc273-7A, with an average of 60.8%. The highest polymorphism information content (PIC) value (0.36) was also recorded for Xwmc273-7A, while the lowest PIC (0.11) was found with Xwmc398-6A, with an average of 0.23. A highly significant correlation (r= 0.872, P0.01) was found between %P and PIC values. Cluster analysis based on phenotypic data classified the ten genotypes into two groups, of which the group-1 genotypes (Line-1, Line-2 and Line-3) showed high tolerance to heat stress by exhibiting lowest HSI values. However, cluster analysis based on SSR markers generated two clusters, where cluster-I contained five genotypes (Line-1, Line-2, Line-3, Debeira and EL-Nilein) tolerant to heat stress, indicating the efficiency of SSR markers in discriminating wheat genotypes. Moreover, four SSRs generated some unique bands or specific for some tolerant genotypes, that could be used as markers associated with heat tolerance in wheat. However, additional markers analysis is still required to validate their usefulness in breading programs.

Tomato (Solanum lycopersicum) is one of the most important crops for human health and nutrition since its fruit is an important source of antioxidants and other bioactive compounds. Many genetic and genomics resources have been developed and are today available for this species, allowing to set up a genomic-assisted breeding approach for improving fruit quality. Among genomic resources available, Solanum pennellii introgression lines (ILs) represent a valuable tool to exploit the genetic diversity present in this wild species. Our goal was to decipher the genetic mechanisms controlling ascorbic acid (AsA) content in tomato fruit. In a previous study, we identified two ILs (IL7-3 and IL12-4) harboring QTLs that increase the content of this compound in the fruit. Crosses between the two lines and selfing of the F1 progeny were performed in order to pyramid the favorable QTLs carried by the 7-3 and 12-4 introgressed regions. Even though the F3 double homozygous plants obtained displayed AsA significantly higher than the cultivated parent, a reduced yield was evidenced due to a negative QTL for yield carried by the 7-3 wild region. In order to disrupt the linkage between favorable and unfavorable traits and to find candidate genes for AsA, sub-lines of the regions IL7-3 and IL12-4 were established. Taking advantage of the very recently release of S. pennellii genome sequence and of the tomato reference sequence (SL2.50), 43 species-specific CAPS markers were designed (21 for region 7-3 and 22 for 12-4) and used to obtain six different sub-lines for IL7-3 and one for IL12-4. The search for candidate genes associated with AsA was carried out by exploring the annotation and the Gene Ontology terms of the genes included in the introgressed regions. As result, we were able to reduce the number of candidate genes controlling AsA in the fruit in each introgressed region. As for the sub-line of IL12-4, it displayed high level of AsA in the fruit, thus allowing to reduce the number of candidate genes from 12 to four. As for sub-lines of IL7-3, preliminary fruit analysis of these sub-lines revealed different AsA in respect to the control genotype M82, indicating that genes controlling this metabolite are still present in the narrowed wild regions. Further molecular, biochemical and phenotypic analyses will be carried out to better characterize the developed sub-lines. Moreover, these novel genotypes might be used in the future as genetic materials for a breeding scheme aimed at obtaining new hybrids or improved varieties with higher antioxidants levels.

Tomato (Solanum lycopersicum) is one of the most important crops used for human consumption worldwide since its fruit is a source of antioxidants and other bioactive compounds, very important for health and nutrition. Unfortunately, the erosion of genetic variability due to the domestication of tomato in most cases has led to the loss of valuable traits. The use of Introgression Line (IL) populations derived from a cross between the cultivated tomato (Solanum lycopersicum) and a wild species could help to restore important fruit quality traits into the genome of cultivated tomato. The Solanum pennellii IL population reconstitutes the wild type genome in 76 overlapping segments in the genetic background of S. lycopersicum (cv. M82). In a previous study, two S. pennelliii introgression lines (IL7-3 and IL12-4) harboring QTLs that regulate the synthesis of ascorbic acid (AsA) and phenolic compounds in the fruit were identified. The QTLs were pyramided into the genetic background of the cultivated tomato M82 using a marker-assisted selection approach. The cross between the two ILs produced different genotypes that were screened by species-specific markers in order to characterize their genomic constitution. The introgressed regions of S.pennellii in M82 were defined by exploring the Sol Genomics Network database (www.sgn.cornell.edu) in order to find polymorphic sequences between the reference genome S. lycopersicum (cv.Heinz) and S. pennellii, which allowed to design CAPS markers. A first molecular analysis was performed with six CAPS markers (three for region 7-3 and 12-4) positioned in the upper, middle and lower part of the introgressed regions. A further analysis with additional CAPS markers provided additional information about the length of the introgressed fragment in the sublines. Particularly, two sub-lines carrying the 7-3 region (analyzed with additional four CAPS markers) showed a wild type fragment of about 3.8 MB. Of the two sub-lines harboring the 12-4 region (analyzed with additional nine CAPS markers), the first sub-line showed about 2.1 MB of the wild type genome while a fragment of about 1.2 MB was found in the second sub-line. On the original introgression 7-3, a total number of 710 genes were mapped, whereas a total of 540 were mapped in the original introgression 12-4. In the selected sub-lines, a reduced number of about 620 genes for both IL 7-3A and IL-7-3B and of more than 300 for IL 12-4A and about 180 genes for 12- 4B were localized in the wild region. Consequently, phenotyping these sub-lines for AsA and phenolics could restrict the number of candidate genes to be further investigated. Preliminary biochemical analysis on tomato fruit of these sub-lines revealed different AsA and phenolics content comparing to the control genotype M82, indicating that genes controlling these metabolites are still present in the restricted wild regions. Further molecular and biochemical analyses will be carried out to better characterize the developed sub-lines. Moreover, these novel genotypes could be used in the future as genetic materials for a breeding scheme aimed at obtaining new hybrids or improved varieties with higher antioxidants levels.

This investigation was carried out at Delta Sugar Factories during (2013), (2014) and (2015) working seasons to minimize the milk of lime consumption which added to the diffusion juice in the juice purification station in a few steps to precipitate and destabilize the non-sugars (impurities).Also to reduce the steam consumption % on beet in the evaporation station and hence reduce the costs during sugar beet processing. From the results obtained, it could be noticed that the analysis of the comparison between the additions of milk of lime on hot and cold diffusion juice gave a high difference values between hot and cold liming in two different production lines , line(1) (hot liming) and line(2) (cold liming). Thin juice purity, non –sugar elimination in juice purification (% beet), juice purification efficiency(%), gain in purity(%) and recovery (%) were higher in cold liming than in hot liming, while non -sugar in thin juice (% beet), color formation in thin juice (IU at 420 nm), thin juice hardness (mg/100DS), sugar loss to molasses (% on beet), and molasses (% on beet) were higher in hot liming than in cold Liming. Also, in the first production line of Delta Sugar Company the steam consumption % on beet is very high values reached to about 43% on beet, so that some trials were occurred to reduce it by addition a new Booster evaporator in parallel with first effect, a new falling film (third effect) and plate evaporator unit (fifth effect). Consequently, the capacity of the first production line increases to 8000 ton beet per day, and so we will hope to increase the overall capacity for the factories to 18000 ton beet per day.