In this study, chemical compositions of the fruits of some important domestic chestnut types and cultivars were investigated. They contained (g/100g dry matter basis) total carbohydrates 75.32 -86.31, total sugar 10.32 -22.79, invert sugar 0

Postbloom fruit drop (PFD) of citrus and Key lime anthracnose (KLA) are caused by Colletotrichum acutatum. Both fungal isolates can infect flower petals, induce young fruit abscission and result in severe yield loss on many citrus cultivars. Previous studies revealed that infection of citrus flowers by C. acutatum caused higher levels of indole-3-acetic acid (IAA), which could be synthesized from the host plant and/or the fungal pathogen. The ability for IAA production by C. acutatum isolates was investigated. Similar to many microorganisms, the production of indole compounds in the medium by C. acutatum was dependent solely on the presence of tryptophan (Trp). In total, 14 PFD and KLA fungal isolates were tested, and revealed that they all were capable of utilizing Trp as a precursor to synthesize IAA and other indole derivatives. High-performance liquid chromatography analysis and chromogenic stains after a fluorescence thin-layer chromatography separation unambiguously identified IAA, tryptophol (TOL), indole-acetaldehyde, indoleacetamide (IAM), indole-pyruvic acid, and indole-lactic acid (ILA) from cultures supplemented with Trp. The data suggest that C. acutatum may synthesize IAA using various pathways. Interestingly, increasing Trp concentrations drastically increased the levels of TOL and ILA, but not IAA and IAM. The ability of C. acutatum to produce IAA and related indole compounds may in part contribute to the increased IAA levels in citrus flowers after infection. ß

The in vitro response of sweet cherry (Prunus cerasus × P. canescens) rootstock Gisela 5 to increasing water deficit in the culture medium was studied. Water stress induced by the incorporation of 1, 2 and 4 % polyethylene glycol (PEG-8000) into the Murashige and Skoog medium was applied for 6 weeks. PEG-induced water stress reduced shoot dry mass, length, water content and relative chlorophyll content. Water stress also induced leaf necrosis without causing loss of viability in the explants. The increase in malondialdehyde content indicated oxidative stress. The activities of antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), peroxidase (POX) and glutathione reductase (GR) were also significantly elevated. The concentrations of K, Ca, Fe and Mn of shoots were decreased.

The in vitro response of sweet cherry rootstock Gisela 5 (Prunus cerasus × Prunus canescens) to increasing concentrations of NaCl (0, 50, 100 and 150 mM) in the Murashige and Skoog culture medium was studied. Induced salinity reduced growth and chlorophyll content in shoots but had no effect on water content. The increase in malondialdehyde content indicated that salinity induced oxidative stress which was accompanied with the visible symptoms of salt injury in the shoots. Antioxidant enzymes, such as superoxide dismutase, ascorbate peroxidase, peroxidase, catalase, and glutathione reductase were also significantly elevated. Although no change was observed in the Cl concentration, Na concentration of shoots significantly rose and NaCl treatments impaired K, Ca and Mg nutrition and induced imbalance in K:Na and Na:Ca ratios.

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