The evaluation of genetic diversity is crucial for breeders to develop strategies and improve the resilience, quality, and adaptability of the date palm. In this study, the genetic diversity of three ...date palm varieties was performed using ISSR-PCR molecular markers to determine its relationship with in vitro propagation response of these varieties. The molecular profiling was performed using ISSR-PCR. A total of 49 loci were produced by the PCR reactions, 38 of which were polymorphic while 11 were monomorphic. The level of polymorphism revealed by ISSR-PCR varied from 33.33% to 100%. The three date palm varieties were grouped into two clusters based on the results of cluster analyses that used morphological data and molecular profiles. Cluster I comprised the ‘Barhy’ variety and Cluster II included ‘Magdoul’ and ‘Amri’ varieties. The clustering analyses revealed the independence of the ‘Barhy’ variety in its characteristics from the other varieties based on either morphological or molecular data. The results of in vitro propagation showed that the ‘Amri’ variety exhibited the highest callus induction frequency (86.28%), callus weight (2.33 g), number of somatic embryos (9.32), number of shoots (14.62), number of roots (4.11), root length (4.63 cm), shoot length (13.61 cm) followed by ‘Magdoul’ and ‘Barhy’ varieties. The ‘Amri’ variety had the shortest callus induction period, at 23.26 days while the ‘Barhy’ variety exhibited the longest period of callus induction (28.55). It was deduced from the study that the ISSR marker reproduced trustworthy patterns of bands to determine the genetic diversity among different date palm varieties that are considered the cornerstone for the genetic improvement of date palms. The understanding of the relationship between genetic diversity and in vitro propagation response of date palm is essential for ensuring the long-term sustainability of its crop. This will facilitate better conservation and development of new date palm varieties that fulfil the needs of farmers and consumers.
Wheat has remarkable importance among cereals in Egypt. Salt stress affects plant growth, development, and crop productivity. Therefore, salinity tolerance is an essential trait that must be ...incorporated in crops. This research aimed to investigate molecular and biochemical indicators and defence responses in seedlings of 14 Egyptian wheat genotypes to distinguish the most contrasting salt-responsive genotypes. Analysis of ISSR and SCoT markers revealed high polymorphism and reproducible fingerprinting profiles for evaluating genetic variability within the studied genotypes. The HB-10 and SCoT 1 primers had the highest values for all the studied parameters. All the tested primers generated a set of 66 polymorphic bands among tolerant and sensitive genotypes. The transcript profiles of eight TaWRKY genes showed significant induction under the salinity treatments. Moreover, the expression of TaWRKY6 for genotypes Sids 14 and Sakha 93 sharply increased and recorded the highest expression, while the expression of TaWRKY20 for Misr 1 recorded the lowest expression. Under salt stress, the total sugar, proline, and phenolic contents increased significantly, while the chlorophyll content decreased significantly. Additionally, five peroxidase and polyphenol oxidase isoforms were observed in treated leaves and clustered into five different patterns. Some isoforms increased significantly as salinity levels increased. This increase was clearer in salt-tolerant than in salt-sensitive genotypes. Eighteen protein bands appeared, most of which were not affected by salinity compared with the control, and specific bands were rare. Generally, the Sids 14, Sakha 93, Sohag 4, and Gemmeiza 12 genotypes are considered salt tolerant in comparison to the other genotypes.
Chamomile (Matricariarecutita L.) is one of the most important medicinal plants with various applications. The flowers and flower heads are the main organs inthe production of essential oil. The ...essential improvement goals of chamomile are considered to be high flower yield and oil content, as well asthe suitability for mechanical harvesting. The present study aimed to improve the flower yield, oil content and mechanical harvestability of German chamomile via chemical and physical mutagens. Three German chamomile populations (Fayum, Benysuif and Menia) were irradiated with 100, 200, 300 and 400 Gray doses of gamma rays, as well as chemically mutagenized using 0.001, 0.002 and 0.003 mol/mL of sodium azide for 4 h. The two mutagens produced a wide range of changes in the flowers’ shape and size. At M3 generation, 18 mutants (11 from gamma irradiation and 7 from sodium azide mutagenization) were selected and morphologically characterized. Five out of eighteen mutants were selected for morphological and chemical characterization for oil content, oil composition and oil quality in M4 generation. Two promising mutants, F/LF5-2-1 and B/HNOF 8-4-2, were selected based on their performance in most studied traits during three generations, as well as the high percentage of cut efficiency and a homogenous flower horizon, which qualify them as suitable candidates for mechanical harvesting. The two mutants are late flowering elite mutants; the F/LF5-2-1 mutant possessed the highest oil content (1.77%) and number of flowers/plant (1595), while the second promising B/HNOF 8-4-2 mutant hada high oil content (1.29%) and chamazulene percentage (13.98%) compared to control plants. These results suggest that the B/HNOF 8-4-2 and F/LF5-2-1 mutants could be integrated as potential parents into breeding programs for a high number of flowers, high oil content, oil composition and oil color traits for German chamomile improvement.
Determining and improving drought-tolerant cultivars is a major goal of plant breeding to face climate change. The productivity of faba bean in Egypt is affected by abiotic stresses, especially ...drought stress. This study evaluated eight Egyptian faba bean cultivars for drought tolerance under three soil water regimes consisting of well-watered (100% field capacity), moderate drought stress (50% field capacity), and severe drought stress (25% field capacity) regimes in pots under greenhouse conditions using biochemical, physiochemical, and molecular parameters. The cultivars Nubariya 1, Nubariya 3, and Giza 716 showed the highest proline content values under 50% field capacity conditions, with 4.94, 4.39, and 4.26 mmol/g fresh weights, respectively. On the other hand, the cultivars Sakha 1, Sakha 4, Nubariya 1, and Nubariya 3 exhibited the highest proline contents (7.8, 7.53, 6.17, and 6.25, respectively) under 25% field capacity treatment. The molecular profiling was conducted using SCoT and SRAP approaches. Fresh leaves were utilized to extract the DNA, and ten primers for SRAP and six for SCoT were used in the PCR procedures. SCoT and SRAP-PCR generated 72 loci, of which, 55 were polymorphic, and 17 were monomorphic. SCoT and SRAP each had 48 and 24 total loci, respectively. The average polymorphism (%) values achieved via SCoT and SRAP were 70.93% and 80%, respectively. Based on the molecular profiles, the cluster analysis identified three clusters. The first cluster comprised Giza 716 cultivars; the second cluster included Sakha 1, Sakha 3, Sakha 4, and Akba 3300 cultivars; the third cluster comprised two cultivars Nubariya 1 and Nubariya3. According to the study’s findings, Sakha 1, Sakha 4, Nubariya 1, and Nubariya 3 are remarkable parents for developing drought-tolerant faba bean genotypes. Additionally, this study concluded that SRAP and SCoT markers recreated trustworthy banding profiles to evaluate the genetic polymorphism among faba bean cultivars, which are regarded as the cornerstone for genetic improvements in crops.
Centaurea is a value-ultimate genus of medicinal plants showing high diversification levels, especially within the Mediterranean basin, and is still traditionally recognized as a complicated taxon. ...So far, few studies utilizing molecular markers have been done on Centaurea spp. towards a better dissection of its phylogeny and accurate assessment of genetic diversity. Here, two functional marker systems, start codon targeted (SCoT) polymorphism and CAAT box-derived polymorphism (CBDP), were implemented to assess the genetic diversity between eight wild Centaurea species in Egypt. Seventeen SCoT and 19 CBDP primers generated 197 and 179 bands, respectively. These primers generated 158 (80.2%) and 131 (73.18%) polymorphic amplicons with an average of 9.29 and 6.89 amplicons per primer, respectively. SCoT primers exhibited higher levels in % of polymorphism, % of heterozygosity, effective multiplex ratio, discriminating power, resolving power parameters compared to the CBDP. In contrast, no significant differences were observed between SCoT and CBDP in polymorphism information content, marker index and mean heterozygosity parameters. The UPGMA (unweighted pair group method with arithmetic mean) dendrogram of the combined data classified the Centaurea species under two major clades; the first comprised two species, whereas the second grouped five species. C. pallescens was kept separated as the most diverged among the eight Centaurea species. Principal component analysis (PCA) topology revealed highly similar results to those obtained from the cluster analysis. Ultimately, our results represent the first report utilising two gene-targeting marker systems as powerful techniques for assessing the genetic variability and relatedness among these eight valuable Centaurea species.
The plant endosomal trafficking pathway controls the abundance of membrane-associated soluble proteins, as shown for abscisic acid (ABA) receptors of the PYRABACTIN RESISTANCE1/PYR1-LIKE/REGULATORY ...COMPONENTS OF ABA RECEPTORS (PYR/PYL/RCAR) family. ABA receptor targeting for vacuolar degradation occurs through the late endosome route and depends on FYVE DOMAIN PROTEIN REQUIRED FOR ENDOSOMAL SORTING1 (FYVE1) and VACUOLAR PROTEIN SORTING23A (VPS23A), components of the ENDOSOMAL SORTING COMPLEX REQUIRED FOR TRANSPORT-I (ESCRT-I) complexes. FYVE1 and VPS23A interact with ALG-2 INTERACTING PROTEIN-X (ALIX), an ESCRT-III-associated protein, although the functional relevance of such interactions and their consequences in cargo sorting are unknown. In this study we show that Arabidopsis (
) ALIX directly binds to ABA receptors in late endosomes, promoting their degradation. Impaired ALIX function leads to altered endosomal localization and increased accumulation of ABA receptors. In line with this activity, partial loss-of-function
mutants display ABA hypersensitivity during growth and stomatal closure, unveiling a role for the ESCRT machinery in the control of water loss through stomata. ABA-hypersensitive responses are suppressed in
plants impaired in PYR/PYL/RCAR activity, in accordance with ALIX affecting ABA responses primarily by controlling ABA receptor stability. ALIX-1 mutant protein displays reduced interaction with VPS23A and ABA receptors, providing a molecular basis for ABA hypersensitivity in
mutants. Our findings unveil a negative feedback mechanism triggered by ABA that acts via ALIX to control the accumulation of specific PYR/PYL/RCAR receptors.
Immature female inflorescences are promising materials for use as explants for the tissue culture of date palm. Four types of MS media were used in this study during the four micropropagation ...stages-starting media (SM), maturation media (MM), multiplication media (PM) and rooting media (RM)-to micropropagate three elite date palm varieties, Amri, Magdoul and Barhy using the immature female inflorescences as explant. The highest percentage of callus induction in all the varieties studied was obtained on the SM1 (9 µM 2,4-D + 5.7 µM IAA + 10 µM NAA). Culturing on the MM1 (4.5 µM 2,4-D + 9.8 µM 2-iP + 1.5 AC) allowed us to obtain the best value in terms of callus weight. After culturing on the PM1 (4.4 µM BA + 9.8 µM 2-iP) produced the highest numbers of somatic embryos and shoots. The explants on RM2 (0.5 µM NAA + 1.25 µM IBA + 3 g AC) showed the highest root numbers and root lengths, while the highest shoot length was achieved on RM3 (0.5 µM NAA + 0.5 µM IBA + 3 g AC). The Amri variety presented the best response among the three varieties in all parameters, followed by the Magdoul and Barhy varieties. In all the stages of micropropagation, the analysis of variance revealed highly significant variations among varieties and culture media, and a significant difference in the number of roots during the rooting stage. The results also showed non-significant differences in the interaction between varieties and culture media, except for shoot length in the rooting stage. The results also reveal the broad sense heritability ranging from low to high for the measured parameters. It can be concluded that the immature female inflorescences can be used as a productive explant source for successful date palm micropropagation using the SM1, MM1, PM1 and RM2 culture media. It can also be concluded that the success of date palm micropropagation not only depends on the concentrations of growth regulators, but also on their types.
Water scarcity, due to physical shortage or inadequate access, is a major global challenge that severely affects agricultural productivity and sustainability. Deficit irrigation is a promising ...strategy to overcome water scarcity, particularly in arid and semiarid regions with limited freshwater resources. However, precise application of deficit irrigation requires a better understanding of the plant response to water/drought stress. In the current study, we investigated the potential impacts of biochar-based soil amendment and foliar potassium-humate application (separately or their combination) on the growth, productivity, and nutritional value of onion (
L.) under deficient irrigation conditions in two separate field trials during the 2018/2019 and 2019/2020 seasons. Our findings showed that deficit irrigation negatively affected onion resilience to drought stress. However, these harmful effects were diminished after soil amendment using biochar, K-humate foliar application, or their combination. Briefly, integrated biochar and K-humate application increased onion growth, boosted the content of the photosynthetic pigments, enhanced the water relations, and increased the yield traits of deficient irrigation onion plants. Moreover, it improved the biochemical response, enhanced the activities of antioxidant enzymes, and enriched the nutrient value of deficiently irrigated onion plants. Collectively, these findings highlight the potential utilization of biochar and K-humate as sustainable eco-friendly strategies to improve onion resilience to deficit irrigation.
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