Rapid and early detection of Fire Blight as the most destructive bacterial disease of apple and pear trees is very important to avoid product loss. The objective of this research was to evaluate the usefulness of visible near-infrared spectrometry for early detection of Fire Blight. Three kinds of samples were selected: healthy leaves (H) from healthy trees and symptomatic (S) and non-symptomatic diseased (MS) leaves from infected trees. For spectral analysis, different preprocessing and processing techniques were carried out. Linear discriminant analysis, quadratic discriminant analysis, Mahalanobis discriminant analysis, soft independent modeling of class analogy (SIMCA) and partial least square-discrimination analysis were applied as classification techniques. Laboratory test by selective culture method was used to detect bacteria. Based on analyses, hyperspectral wavelengths for detection of H, MS and S leaves were obtained. SIMCA proved to be the strongest among all classifiers to discriminate healthy leaves from diseased leaves. The results indicated that structure intensive pigment index and modified simple ratio were sensitive to discriminate H-S, H-MS and S-MS leaves. Randomized difference vegetation index showed potential to classify H-S and S-MS samples. Anthocyanin reflectance index showed potential to discriminate H-MS samples. Finally, modified triangular vegetation index1 and modified chlorophyll absorption ratio index1 were identified and considered as spectral indices to discriminate S-MS samples. Based on these results, this technique is reliable for detecting non-symptomatic diseased leaves and is capable of early detection of Fire Blight before spreading.

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The aim of this study is to demonstrate the effects of water shortage, which may occur in different periods, on wheat grain yield and quality. One of the most important factors limiting wheat yield in the Southeastern Anatolia Region of Turkey is drought, which is caused by inadequate precipitation and irregular distribution over the year. Four different bread and durum wheat cultivars (Sarıçanak-98, Fırat-93, Pehlivan, Ceyhan-99), which are widely cultivated in the region, were used as the material of the study. The experiment was carried out with 3 replications, according to the random blocks design. The research was carried out under greenhouse conditions. The effects of four different drought conditions on the wheat's development, yield and mineral content were investigated under irrigation (K0), early drought (K1), late drought (K2) and full drought (K3). According to the results, a 9.12% loss in chlorophyll content was observed under irrigated conditions (K0). 21.68% leaf area, 28.98% plant green area, and 52.09% plant height declines were recorded. The amount of potassium (K) was found to change between 2.86 mg (K3) and 34.77 mg (K2), while the amount of calcium (Ca) changed between 0.67 mg (K3) and 33.23 mg (K3) and the amount of sodium (Na) changed between 0.20 mg (K1) and 27.05 mg (K0) in the root and stem of plants.