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101.
Bal  Erdinc  Torçuk  Ali İzzet  Özer  Cengiz 《Erwerbs-Obstbau》2022,64(2):127-133

The study was carried out to determine the effect of melatonin on quality and postharvest life of sweet cherries (Prunus avium L.) cv. ‘Sweetheart’ during storage. The fruits were dipped at different concentrations of melatonin (0, 250, 500 and 1000?µmol l?1 for 10?min) and distilled water as control. The changes of sweet cherries were assessed at 7?day intervals by evaluating the following quality parameters: firmness, soluble solids content, titratable acidity, respiration rate, color values (L* and chroma), ascorbic acid content, total anthocyanin content, total phenolic content, and antioxidant activity. The results showed that increasing the dose to 1000?µmol l?1 melatonin had a remarkable effect on maintaining the quality of sweet cherry. 1000?µmol l?1 and 500?µmol l?1 melatonin treatments significantly inhibited the decrease in firmness, ascorbic acid, total phenols, total anthocyanin, antioxidant content and reduced color changes and respiration rate. However, the total soluble solids content and titratable acidity of the fruit were not influenced by melatonin applications. These findings indicate that melatonin treatment may be effective in maintaining quality and bioactive compounds of sweet cherry fruit.

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102.
This study examines the relationships between forest structural diversity indices and aboveground stand carbon storage for even-aged and pure Scots pine stands located in the Sar?çiçek Forest, Northern Turkey. In the even-aged Scots pine stands, 293 sample plots were selected to represent various stand conditions such as site quality, age, and stand density. The stand structural diversity, including Shannon’s, improved Shannon, Simpson’s, McIntosh, Margalef, and Berger–Parker indices, was used to correlate the stand carbon storage values. Positive partial correlation coefficients between stand carbon storage and forest structural diversity indices, including the improved Shannon index (r?=?0.770), Shannon’s index (r?=?0.742), Simpson’s index (r?=?0.703), the Berger–Parker index (r?=?0.657), the Gini index (r?=?0.390), and the Margalef index (r?=?0.327), were found at the 0.01 level. These results offer an enhancement of theories concerning positive relationships between stand carbon storage and stand structural diversity for pure and single-species forests. Moreover, regarding biodiversity suitability and stand carbon storage as carbon sinks, the results illustrate that forest stands with higher structural diversity may be preferred when used to mitigate global warming.  相似文献   
103.
Nitrogen is an essential nutrient for greenhouse-grown lettuce (Lactuca sativa L.); however, excessive nutrient availability causes disease and detrimental effects on the leaf and root development. In this study, nitrogen content of the lettuce leaves was estimated by determining the chlorophyll concentrations of the leaves using image processing technique. The Hoagland solution was used as a fertilizer in five different doses (control, quarter of the solution, half of the solution, standard solution, and two times more of the solution). Multilayer perceptron neural network (MLPNN) model was developed based on the red, green, and blue components of the color image captured to estimate chlorophyll content and chlorophyll concentration index (SPAD values). According to the obtained results, the MLPNN model was capable of estimating the lettuce leaf chlorophyll content with a reasonable accuracy. The coefficient of determination was 0.98, and mean square error was 0.006 in validation process.  相似文献   
104.
Commercial bath sponge population in the Mediterranean has been recently reduced due to diseases and the depletion of natural banks. The commercial supply is far below the demand on the last 10–15 years. In this study, we aimed to investigate the farming performance of Spongia officinalis in the Dardanelles. Sponges collected from the Dardanelles cut into pieces of different weight. They were divided into two groups depending on the wet weight ranging from 50 to 150 g (mean weight 102.6 ± 4.81 g) and from 160 to 360 g (mean weight 235.8 ± 8.56 g). Three rope systems located parallel to each other with 6–7 m inter‐distance were constructed for the cultivation of sponges. At the end of the study, while small‐sized sponges could reach mean wet weight of 120.7 ± 14.8 g, large‐sized sponges reached mean wet weight of 247.6 ± 22.4 g. Growth rates were estimated 5–17% at 21st month. The survival rates were found 82% and 88%.  相似文献   
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