Response of costata persimmon trees to different rootstocks and NK fertilization 2. fruit quality at harvest and post-storaget [electronic resource].

Includes references.

This investigation was carried out in 2000 and 2001 to study the effect of rootstock (seadling and Trabols), nitrogen (0, 600, 1200 and 1800 g ammonium nitrate per tree), potassium (0, 600 and 1200 g potassium sulphate per tree) and their interactions on fruit quality at harvest date and after storage at 1-2"C or at room temperature of costata persimmon trees. The results are summarized as follow: 1. Regardless of potassium fertilization and rootstock, nitrogen fertilization increased fruit weight and total chlorophyll at harvest date and weight loss and total chlorophyll after 60 days from storage at 1-2"c. Whereas, it decreased fruit TSS and total sugars at harvest date and after storage at 1-2"C or at room temperature, fruit firmness, tannins and pectin at harvest date or after cold storage and reducing sugars at harvest date. The nitrogen fertilization did not affect fruit carotene at harvest date and after storage at 1-2"C or at room temperature, non-reducing sugars at harvest date, fruit acidity after storage at 1-2"C or at room temperature and fruit weight loss, fruit firmness, total chlorophyll, tannins and pectin after storage at room temperature. 2. Regardless of nitrogen fertilization and rootstock, potassium fertilization increased fruit weight and reducing sugars at harvest date only, fruit TSS, total sugars and carotene at harvest date and after storage at 1-2"C or at room temperature and fruit acidity at harvest date and after cold storage, but decreased fruit tannins and pectin at harvest date. Potassium fertilizer did not affect fruit firmness and total chlorophyll at harvest date and after storage at 1-2°C or at room temperature, fruit weight loss after storage at 1-2"C or at roorn temperature, non-reducing sugars at harvest date, fruit acidfty after 30 days at roorn temperature and fruit tannins and pectin after 60 days at 1-2"C or after 30 days at room temperature.

Summary in Arabic.

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