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Realistic simulations of saline field conditions and effective monitoring of phenotyping parameters in an expeditious, non-destructive manner are imperative to successful breeding of genotypes for salinity stress tolerance. This study aimed to spectrally assess the growth, water relations and ion contents of wheat under simulated saline field conditions using the subsurface water retention technique (SWRT) and three salinity water levels (control, 6, and 12 dS m−1). Phenotypic parameters and hyperspectral signatures of the canopy within the 350–2500 nm range were measured at the flowering stage. Multivariate analysis, including correlation, partial least squares regression, simultaneous b-coefficient and variable importance for projection (VIP), and stepwise multiple linear regression were used in the same order, to extract sensitive wavebands and effective singular wavelengths. Binary effective wavelengths as normalized spectral indices (NDSIs) were constructed and related to phenotypic parameters for pooled data and for each salinity level and cultivar. The results confirmed that the shoot dry weight (SDW), water relations and ion contents parameters were effective as screening criteria for evaluating the salt tolerance of wheat cultivars under simulated saline field conditions. It was possible to assess the phenotypic parameters by using hyperspectral canopy signatures over a broad spectrum range. All parameters exhibited stronger relationships with the wavelengths extracted in the visible-infrared (VIS) and red edge regions than those extracted in the near-infrared (NIR) and shortwave-infrared (SWIR) regions. Six wavelengths within the VIS region, five within the red edge and SWIR-1 regions, eleven within the NIR region, and nine within the SWIR-2 region were extracted as effective bands. The NDSIs based on VIS/VIS, red edge/red edge, red edge/VIS, NIR/VIS, NIR/red edge, and NIR/NIR were more appropriate for assessing the phenotypic parameters than indices based on SWIR/SWIR and SWIR/NIR, except for the SDW, K+ and Ca2+ contents, which showed strong correlations with the latter NDSIs. The close relationship between SDW and the water relations and ion contents parameters on one side and the high predictive power of the NDSIs based on the VIS, red edge, and NIR wavelengths in the assessment of phenotypic parameters on the other side indicates that the hyperspectral reflectance data and band selection techniques could be used for the indirect assessment of water relations and ion content of wheat under saline field conditions.

Fennel is one of the most significant medicinal and aromatic herbs. It is used as a culinary ingredient and has an essential role as a raw material in the pharmaceutical industry. Many researchers across the world are working to increase the active components in the essential oil of medicinal and aromatic plants under organic farming. Growth promoters are one of the most effective methods for stimulating secondary metabolite production under organic agriculture. The objectives of this study were to investigate how foliar sprays of yeast extract (Y) and/or chitosan-oligosaccharide (CHO) affected the growth and yield of organic fennel (Foeniculum vulgare spp. vulgare Mill.) and if these applications can stimulate the production of pharmaceutical active ingredients in fennel fruits. Fennel foliage was subjected to foliar spray of Y at concentrations of 0 (Y0), 2 (Y1), and 4 (Y2) g L−1, and CHO at concentrations of 0 (CHO0), 60 (CHO1), and 120 (CHO2) mg L−1 twice. The results revealed that both Y and CHO treatments promoted growth parameters and leaf pigments content. Total phenols and nutritional content (N, P, K, Ca, and Mg) in fennel fruits were also improved. Furthermore, Y and CHO treatments enhanced fruit and oil productivity. Foliar spraying with Y and/or CHO, as well as their combination, resulted in significant modification in main pharmacological active components in fennel essential oil. Treated plants with Y1 had the lowest proportion of estragole (24.61 %), an undesirable component in fennel oil, and the highest concentration of anethole (64.50 %), which improved the oil quality. While treated plants with CHO1 or CHO2 displayed an increase in estragole content by about 33.34 and 46.59 % compared with Y1-plants, respectively. These new findings demonstrated that applying Y2 or CHO at both levels not only increased fennel growth and yield, but also contributed to increasing estragole and decreasing anethole concentration, and both had a negative impact on essential oil quality. However, applying Y1 enhanced fennel productivity as well as essential oil quality.

Anther culture response of six wheat genotypes and their F 1 crosses was investigated. Results indicated that considerable genetic variation among the tested genotypes was observed. Calli were obtained from all wheat genotypes studied. The percentage of anthers that developed calli ranged from 0.67% for Gemmeiza-9 to 18.00% for the cross (Gemmeiza-7 × Sids-4). Plants were regenerated from 19 out of 21 wheat genotypes. The highest frequencies of green plantlets were achieved from the two crosses (Giza-164 × Gemmiza-9 and Giza-164 × Line-115), while the lowest ones were obtained in the cross (Giza-164 × Sids-4). Generally, crosses showed a better response in anther culture than their parental genotypes. Significant and positive heterotic effects were observed in some crosses for callus induction and green plant regeneration. Ninety-four doubled haploid lines, which were derived from five F 1 crosses and their respective parents were evaluated under field conditions. Some doubled haploid lines that resulted from these crosses performed well and transgressed significantly the higher-yielding parent and the check variety.