Crop wild relatives contain a greater variety of phenotypic and genotypic diversity compared to their domesticated counterparts. Trifolium crop species have limited genetic diversity to cope with biotic and abiotic stresses due to artificial selection for consumer preferences. Here, we investigated the distribution and evolution of nucleotide-binding site leucine-rich repeat receptor (NLR) genes in the genus of Trifolium with the objective to identify reference NLR genes. We identified 412, 350, 306, 389 and 241 NLR genes were identified from Trifolium. subterraneum, T. pratense, T. occidentale, subgenome-A of T. repens and subgenome-B of T. repens, respectively. Phylogenetic and clustering analysis reveals seven sub-groups in genus Trifolium. Specific subgroups such as G4-CNL, CCG10-CNL and TIR-CNL show distinct duplication patterns in specific species, which suggests subgroup duplications that are the hallmarks of their divergent evolution. Furthermore, our results strongly suggest the overall expansion of NLR repertoire in T. subterraneum is due to gene duplication events and birth of gene families after speciation. Moreover, the NLRome of the allopolyploid species T. repens has evolved asymmetrically, with the subgenome -A showing expansion, while the subgenome-B underwent contraction. These findings provide crucial background data for comprehending NLR evolution in the Fabaceae family and offer a more comprehensive analysis of NLR genes as disease resistance genes.

Nutrient deficiency negatively affects the yield and quality of citrus fruit. The present experiment was carried out to investigate the improvement in fruit yield and juice quality of Kinnow (Citrus reticulata L.) by foliar application of nano-biochar suspension (NBS). The experiment was carried out in a citrus farmer’s orchard with a history of low fruit yield, using a randomized complete block design. Four NBS treatments, i.e., 0% (control), 1, 3, and 5%, were applied through foliar application at the flowering stage. Foliar application of NBS at 5% and 3% significantly (p < 0.05) improved flowering, fruit retention, fruit set, fruit size, length, weight, diameter, juice volume levels, and minimized fruit dropping. The electrical conductivity of the juice was significantly decreased by increases in NBS concentration. Total dissolved solids increased slightly with treatments as compared to control. However, NBS foliar application did not show significant effects on nitrogen (N), potassium (K), and sodium (Na) leaf contents, but had some effect on phosphorus (P) content. Principal component analysis and a correlation matrix revealed significant (p < 0.05) positive and negative associations among the studied traits. The results of the current experiment showed that all parameters were significantly improved with the application of NBS at 3 and 5%, except that N, K, and Na levels were unaffected. The most encouraging results were achieved at a concentration of 5% NBS. In conclusions, the foliar application of NBS had a significant positive impact on fruit yield and juice quality.

The present study was conducted to evaluate variation in nickel stress tolerance in a set of 10 canola cultivars (Leand, AC Excel, Faisal Canola, Shiralee, Oscar, Punjab Canola, CON-II, Rainbow, Dunkeld, and Cyclone) at the early growth stages, i.e., germination and seedling stage. The seeds of all canola cultivar were obtained from the Ayub Agricultural Research Institute, Faisalabad, Pakistan. Ten seeds of each cultivar were sown in each of Petri plates moistened with varying levels (15, 30 and 45 mg/L) of nickel in Hoagland nutrient solution. Data for different growth indices were recorded such as germination stress index (GSI), shoot length stress index (SLSI), root length stress index (RLSI), and seedling fresh (SFWI) and seedling dry weight indices (SDWI). Based on different growth indices, three canola cultivars, i.e., CON-II, Faisal Canola and Leand proved to be potential source of variation for Ni tolerance provided if they maintain their degree of Ni tolerance at the later growth stages. However, Oscar was the most sensitive to Ni stress of all 10 cultivars evaluated in the current study.