Genetic diversity of the chemical composition and pod production of Prosopis juliflora trees grown in Saudi Arabia.

This investigation was conducted to evaluate pod and chemical component traits and the genetic diversity of Prosopis juliflora genotypes at two locations. The selected locations were in the middle (Qassim region) and western (Jeddah region) areas, representing two agro-climatic zones of Saudi Arabia. The measured pod characteristics included production, weight, length, filling period, and chemical composition. A wide range of variations in pod yield and chemical traits were observed in the different agro-climatic regions. The results revealed that the mean values ranged from 9.5 kg tree-1 (Jeddah) to 14.2 kg tree-1 (Qassim) for pod yield, 3.1 g pod-1 (Qassim) to 3.7 g pod-1 (Jeddah) for pod weight, and 14.8 cm (Qassim) to 16.6 cm (Jiddah) for pod length. The results of genetic diversity indicated that Prosopis genotypes in each location were distributed in three different clusters in the two regions at 60 Euclidean distances. The principal component analysis (PCA) showed that the two components (PC1 and PC2) explained 25.03 % and 20.03 % of the overall variance, respectively, which is over 45 % of the variability. The heatmap revealed that genotypes Q20, Q21, and Q24 at the Qassim location and genotypes J1, J6, and J7 at the Jiddah location exhibited positive and significant correlations with pod yield. It can be concluded that superior Prosopis genotypes (Q20, Q21, Q24, J1, J6, and J7) were identified with good traits (pod yield, pod-filling period, and protein %) in each location and may be used in the future for the selection of elite genotypes.

Molecular breeding for rust resistance in wheat genotypes.

Rusts are a group of major diseases that have an adverse effect on crop production. Those targeting wheat are found in three principal forms: leaf, stripe, and stem rust. Leaf rust causes foliar disease in wheat; in Egypt, this causes a significant annual yield loss. The deployment of resistant genotypes has proved to be a relatively economical and environmentally sustainable method of controlling the disease. Gene pyramiding can be performed using traditional breeding techniques. Additionally, pathotypes can be introduced to examine specific leaf rust genes, or the breeder may conduct more complex breeding methods. Indirect selection via DNA markers linked to resistance genes may facilitate the transfer of targeted genes, either individually or in combination, even in a disease-free environment. The use of selective crosses to counter virulent races of leaf, stripe, and stem rust has resulted in the transfer of several resistance genes into new wheat germplasm from cultivated or wild species. Quantitative trait locus (QTL) technology has been adopted in a wide variety of novel approaches and is becoming increasingly recognized in wheat breeding. Moreover, several researchers have reported the transference of leaf and stripe rust resistance genes into susceptible wheat cultivars.

Isolation and identification of allergens and biogenic amines of Prosopis juliflora genotypes

Background: Prosopis, or mesquite (Prosopis juliflora (Sw.) DC.), was introduced in Saudi Arabia several decades ago and is heavily used in street, roadside, and park plantations. It shows great adaptation to the prevailing climatic conditions such as high temperature, severe drought, and salinity and spreads naturally in many parts of the Kingdom. This research was conducted to isolate allergen proteins and biogenic amines from the pollen grains of P. juliflora genotypes in Saudi Arabia from two regions, namely Al-Qassim and Eastern regions. Results: The results showed that 18 different allergen proteins were detected in P. juliflora genotypes, with molecular weight ranging from 14 to 97 kDa. Moreover, P. juliflora genotypes from the two studied regions contained eight biogenic amines, namely histamine, tyramine, tryptamine, ß-phenylethylamine, butricine, codapherine, spermidine, and spermine. All genotypes from the Al-Qassim region were found to contain all eight amines, while in the Eastern region, histamine was absent in three genotypes, spermine was absent in six genotypes, and spermidine was absent in three genotypes. Genotypes B23, E20, and E21 had the lowest biogenic amine quantity. Conclusions: All identified proteins from mesquite trees from both regions (Eastern and Al-Qassim) cause allergies in patients who are sensitive to pollen grains. Bioamines, except histamine and tyramine, were recorded at varying concentrations in different genotypes.