To investigate the effects of water withholding on 17 tomato (Solanum lycopersicum L.) landraces collected from different climatic zones of Iran and two commercial hybrids, the polyphasic OJIP fluorescence transient, relative water content (RWC), electrolyte leakage (EL) and vegetative growth parameters were analyzed. Duncan’s multiple range test (DMRT) for all the studied parameters and drought factor index (DFI) based on performance index on the absorption basis (PIabs) were used for screening the plants based on their tolerance to drought condition. Result showed that compared to the control plants, vegetative growth parameters, RWC, PIabs, relative maximal variable fluorescence (FM/F0), maximum quantum efficiency of PSII (FV/FM), quantum yield of electron transport (ΦE0) and electron transport flux per reaction center (RC) (ET0/RC) were decreased, whereas, EL, quantum yield of energy dissipation (ΦD0), specific energy fluxes per RC for energy absorption (ABS/RC) and dissipated energy flux (DI0/RC), which are closely related to the incidence of photoinhibition were increased in plants exposed to water withholding. DMRT and DFI screening results clearly categorized the landraces into three groups (tolerant, moderately sensitive and sensitive). Tolerant landraces showed less change for most of the measured parameters compared to sensitive and moderately sensitive landraces. We found that adapted landraces to dry climates had a higher tolerance to drought stress. Principal component analysis (PCA) revealed that FM/F0, FV/FM, ΦE0, ΦD0, PIabs, ABS/RC, ET0/RC and DI0/RC parameters are the most sensitive parameters for detection of impact of drought stress on tomato plants. In conclusion, the eight parameters have the potential to identify the drought injury in tomato seedlings.

A field experiment with rain-fed winter wheat investigated the nutritional aspects of paper-mill sludge as a mulch and incorporated into the topsoil. Treatments with chemical fertilizers were also used as controls. Paper-mill sludge used as mulch with high rate (100 MG ha−1) and also the combined N and K mineral fertilizer treatments increased yield when a low potassium otherwise caused potassium deficiency in wheat with high specific surface soil. High soil Ca : K molar ratio by incorporation lowered potassium uptake and yield, with visual symptoms of potassium deficiency. A very high Gapon selectivity coefficient (KG) for K exchange against Ca + Mg (16.58 (L/mole)0.5) produced a nonlinear normalized exchange isotherm in favor of potassium with these soils containing high illite. Ca and K which are released by sludge decomposition are diverged in soil when mobilized by rain infiltration, lowering Ca : K molar ratio. Low soil Ca : K molar ratio may be expected by surface sludge application relative to incorporation, due to greater rain infiltration through upper soil layers and their effluent pore volumes per unit depth. Ca from triple superphosphate by the P, N, and K mineral fertilizers combined also reduced potassium uptake and yield relative to N and K combined.

Changes in carbohydrates, enzymes, and pigments were investigated in the Red Garlic (Allium sativum L.) cv. Azarshahr bulbs in storage from harvest to sprouting. For storage period, garlic cloves of the same diameter with 3-4 g weight were arranged in dark condition and exposed to 4 and 21°C, separately. Soluble sugar, total sugar, glucose, sucrose, fructose, starch, chlorophyll a, b, ab, carotenoid, anthocyanin, lipase, α-amylase, and protease were measured every 2 weeks up to sprouting time. Result revealed that starch, lipase, and protease levels declined at the end of storage when clove sprouting started at both 4 and 21°C storage temperature. Starch, glucose, chlorophyll a, b, ab, and carotenoid content during the first 14 days and sucrose at 42 days showed a decreasing trend. Anthocyanin showed an increasing trend 14 and 42 days after harvesting and then decreased at the end of storage (when sprouting began) at both 4 and 21°C storage periods. Finally, starch, glucose, and sucrose measurement can be used as a criterion to predict sprouting time of garlic, due to the decrease in the levels of starch, lipase, and protease, and increase in the levels of α-amylase, glucose, and sucrose in garlic cloves under storage.

Although the micronutrient boron (B) apparently exerts no influences on the induction of somatic embryogenesis of cultured carrot petiole explants, strong influences on the development of somatic embryos were observed (0-8 mg l )1 B). At lower B concentrations the development of roots is promoted with simultaneous retardation of shoot development and at higher B concentrations shoot development is favored at the expenses of the development of the root system. Parallel to this, the ratios of concentrations of endogenous indole-3

A field experiment was conducted to assess the influence of salicylic acid and some important macro and micro elements on anthocyanin content of coriander (Coriandrum sativum L.) leaves as antioxidant, at the experimental field of Gorgan University, Golestan, Iran, in 2007. Based on the soil analysis nitrogen, phosphorus, potassium and zinc fertilizers were added to the experimental field with 75, 45,170 and 30 kg/ha, respectively. Salicylic acid at the rate of 10 -4 molar, iron, magnesium, molybdenum and boron in a rate of 2-3 g/L were sprayed on foliage part two times at 40 th and 47 th days after sowing. Other plots were sprayed with distilled water. Results showed that application of zinc and nitrogen significantly increased and decreased anthocyanin content in coriander leaves as compared with control and led to the highest and the lowest rates of anthocyanin, respectively. Also other treatments did not show significant difference than control but phosphorus and potassium had negative effect on anthocyanin content, while other treatments increased it insignificantly.