Evaluation of Inter-Specific Hybrid of P. atlantica and P. vera L. cv. ‘Badami - Riz-e-Zarand’ as Pistachio rootstock to Salinity Stress According to Some Growth Indices and Eco-physiological and Biochemical Parameters

In order to evaluate the inter-specific hybrid of P. atlantica Desf. and P. vera L. cv. ‘Badami- Riz-e- Zarand’ to salinity stress, a factorial experiment was conducted based on completely randomized design with 0, 60 and 120 mM of salinity levels of sodium chloride, calcium chloride and magnesium chloride (3:2:1) with four replications on ‘Qazvini’, ‘Badami-Riz-e-Zarand’ and inter-specific of P. atlantica Ч P. vera cv. ‘Badami-Rize-Zarand’ rootstocks of pistachio. The results showed that salinity has increased proline content of leaves. Chlorophyll index, relative water content of leaf, leaf area, shoot and root fresh and dry weight, stem diameter and number of leaves were decreased by increasing salinity. Rootstocks responded differently to salinity, so that the most reduction in chlorophyll index, leaf area and leaf number were observed in ‘Badami-Riz-e-Zarand’ rootstock and the least reduction was observed in the hybrid

IS Annona emarginata CAPABLE OF ACCUMULATE ESSENTIAL HEAVY METALS WITHOUT DAMAGES IN THE METABOLISM?

ABSTRACT This study aimed to evaluate if ionic strength variation causes differential accumulation of heavy metals in plants of Annona emarginata (Schltdl.) H. Rainer var. ‘terra-fria’, modifying gas exchange and dry matter production. The seedlings were cultivated under different ionic strengths of the ‘Hoagland and Arnon’s’ nutrient solution (75% I, 50% I and 25% I). At 180 days after the application of the treatments, the effects of the essential heavy metals on the physiological parameters and foliar ionic concentration were assessed. The leaf gas exchanges and vegetative growth were affected by the variation in the essential heavy metals, with positive effects on the plants that were treated with 75%I. The seedlings that were grown under 75% I presented higher concentrations of Zn (24.2mg kg-1). On the other hand Fe (453mg kg-1) e Mn (803.5mg kg-1) accumulated more under 25% I, but gas exchanges and vegetative growth were reduced, compared to 50%I and 75%I. We can conclude that the ionic strength variation alters gas exchange and the dry matter accumulation, causing differential accumulation of Fe, Mn and Zn in A. emarginata, occurring inverse relationship between increased ionic strength and Fe and Mn content, besides directly relationship to the Zn content

Effects of nitrogen form on growth, CO2 assimilation, chlorophyll fluorescence, and photosynthetic electron allocation in cucumber and rice plants*

Cucumber and rice plants with varying ammonium (NH4 +) sensitivities were used to examine the effects of different nitrogen (N) sources on gas exchange, chlorophyll (Chl) fluorescence quenching, and photosynthetic electron allocation. Compared to nitrate (NO3 −)-grown plants, cucumber plants grown under NH4 +-nutrition showed decreased plant growth, net photosynthetic rate, stomatal conductance, intercellular carbon dioxide (CO2) level, transpiration rate, maximum photochemical efficiency of photosystem II, and O2-independent alternative electron flux, and increased O2-dependent alternative electron flux. However, the N source had little effect on gas exchange, Chl a fluorescence parameters, and photosynthetic electron allocation in rice plants, except that NH4 +-grown plants had a higher O2-independent alternative electron flux than NO3 −-grown plants. NO3 − reduction activity was rarely detected in leaves of NH4 +-grown cucumber plants, but was high in NH4 +-grown rice plants. These results demonstrate that significant amounts of photosynthetic electron transport were coupled to NO3 − assimilation, an effect more significant in NO3 −-grown plants than in NH4 +-grown plants. Meanwhile, NH4 +-tolerant plants exhibited a higher demand for the reduced form of nicotinamide adenine dinucleotide phosphate (NADPH) for NO3 − reduction, regardless of the N form supplied, while NH4 +-sensitive plants had a high water-water cycle activity when NH4 + was supplied as the sole N source