Journal of Nuts
Volume:13 Issue: 2, Spring 2022

In order to evaluation of  the tolerance of four pistachio rootstocks to salinity stress an experiment was performed as factorial in framework completely randomized design with four replications. Factors included rootstocks (‘Badami-e- Riz-e-Zarand’, ‘Ghazvini’, ‘Akbari’ and UCB-1) in four levels and salinity (0, 75 and 150 mM) in three levels.  Results showed that rootstocks had different responses to salinity. The highest specific leaf weight and chlorophyll fluorescence parameter (Fv/Fm) were observed in ‘Badami-e- Riz-e-Zarand’ and ‘Ghazvini’ rootstocks. Also, potassium and calcium concentration of shoot in ‘Badami-e- Riz-e-Zarand’, ‘Ghazvini’ and, ‘Akbari’ rootstocks were higher compared to UCB-1. The UCB-1 rootstock had higher leaf area, relative water content (RWC) and chlorophyll-a content than the other rootstocks. The results of cluster analysis showed that salinity changed the position of the ‘Akbari’ and UCB-1 rootstocks in cluster whereas the position of ‘Badami-e- Riz-e-Zarand’ and ‘Ghazvini’ rootstocks unchanged in cluster.

The purpose of this study was to evaluate the effects of a combination of zinc oxide nanoparticles (Nano-ZnO) and fennel essential oil (FEO) on the quality characteristics of fresh pistachio. The potato starch-based films containing different levels of Nano-ZnO (1, 3, and 5% w/w), and FEO (1, 2, and 3% w/w) were prepared by the casting method. The fresh Akbari pistachios were packed in these bio-nanocomposite films. The physicochemical and sensory properties and the growth of Aspergillus flavus and aflatoxin B1 production were investigated during 15 days of refrigerated storage (~ 4°C). Results showed that by packaging fresh pistachios in bio-nanocomposite films, the moisture, carbohydrate, and fat contents of pistachios and the sensory parameters (texture, flavor, appearance, and overall acceptability) of them were improved during refrigerated storage. The weight loss of control significantly was higher than packed samples in bio-nanocomposite films (p<0.05). Usage of bio-nanocomposite films leads to a decrease in the growth of Aspergillus flavus and aflatoxin production in pistachios during storage periods. Finally, the results demonstrated that potato starch/5% Nano-ZnO/3% FEO bio-nanocomposite film improved the physicochemical and sensory properties and had the best effect on mold spoilage reduction of fresh pistachios; hence, it can be used as packaging for fresh nuts.

Brown leaf spot (leaf blight) is a fungal disease caused by Mamianiella coryli, causal agent of early defoliation in summer, and is widely distributed in hazelnut (Corylus avellana L.) growing regions of Iran. During 2019-2020, 48 native and foreign hazelnut cultivars/ and or genotypes were evaluated for susceptibility against M. coryli under natural infection conditions at Astara Horticultural Research Station (northern Iran). One hundred infected leaves were randomly collected from four geographical directions and middle of canopy of each hazelnut tree. Disease severity index (DSI%) on leaves was calculated based on 1-5 rating system (1= >0 to 20% leaf area affected and 5= >80% of leaf area affected) and levels of reactions were determined based on DSI% (<1%= Highly resistant and >50%= Highly susceptible). None of the hazelnut cultivars had genetic resistance to M. coryli and all of the genotypes were grouped into two categories included susceptible (25.1-50%) and highly susceptible. Seven cultivars and/or genotypes included Souchi, Gerdoii 89, Pashmineh 89, Rimsky, Segorbe, Dedobestani and Pronnes were high susceptible and the rest were in the susceptible categories. It was concluded that sanitation of leaf debris in the fall, pruning for better air circulation or fungicide applications in the spring might be useful in disease outbreak conditions.

‘Bahri Koz’ is a walnut cultivar that reaches a mid-early harvest maturity and has some superior fruit traits. In 2019, the cultivar was registered and patented by the Variety Registration and Seed Certification Center of the Republic of Türkiye Ministry of Agriculture and Forestry. To determine the pomological and phenological traits of the ‘Bahri Koz’, 27 different traits were examined. The pomological analysis determined that the in-shell nut weight of ‘Bahri Koz’ was 12-14 g, the kernel weight was 6.5-7.0 g, and the kernel ratio was 51-54%. The shell and kernel of the cultivar were determined to be light in color and the surface of the shell to have a smooth structure. ‘Bahri Koz’ had superior traits compared to the ‘Chandler’ cultivar in terms of some of the pomological parameters such as in-shell nut weight, kernel weight, and kernel percentage. The new cultivar was seen to reach leafing, harvest maturity, and defoliation at an earlier date than ‘Chandler’. The dichogamy status of the cultivar was determined to be protandrous and in this respect, a pollinator cultivar was recommended for the establishment of orchards with ‘Bahri Koz’. This cultivar was also shown to be rich in lipid and unsaturated fatty acid content.

Aflatoxin is an important fungal contaminant in various crops. The substrate and its compounds are involved in the growth of fungus and the production of toxins. In order to investigate correlation between sugar and lipid content as the major chemical composition of pistachio kernels with Aspergillus flavus growth and aflatoxin production, the total sugar content was extracted by phenol-sulphoric method and estimated by spectrophotometry. The lipid was also extracted by Soxhlet method. A toxigenic A. flavus strain was used for the study of the fungal growth and aflatoxin B1 production. For that, 20 gram of kernels of different pistachio cultivars were inoculated with 1 ml of fungal spore suspension (2×106 spores/ml) in a completely randomized design with three replications. Eight days after inoculation, the average percent of fungal growth and colonization of A. flavus were calculated. The aflatoxin produced in inoculated pistachios was extracted by Best Foods (BF) method and measured by thin layer chromatography (TLC). The results showed that there was no significant difference in the amount of sugar content in different cultivars of pistachios kernel but the amount of total lipid content was different (P≤0.05). Results of statistical analysis showed that there was no significant correlation between sugar content with fungal growth and aflatoxin production in pistachio cultivars as well as lipid percentage and aflatoxin B1 production. Therefore, to find sources of resistance to A. flavus in commercial pistachio cultivars in aflatoxin management programs, these two factors cannot be used as a standard scale of resistance.

Pistacia atlantica Desf.is one of the main wild species of Pistacia in Iran and one of its products is an oleo-gum-resin briefly called Saqez gum. The effect of Ethrel injection (EI) on Saqez gum production was studied during summer 2018 at three habitats (Kuh-e Birk, Goharkuh and Mirabad) inSistan and Baluchestan province, Iran. Four treatments, 0 (distilled water), 10, 20 and 30% concentration of Ethrel, were administered by injection into the tree trunk. The investigation was carried out in a randomized complete block design and 36 trees were injected. Saqez gum essential oil (EO) was extracted by Clevenger apparatus and identification and quantification of EO components were performed by GC-MS and GC-FID, respectively. The results showed that applying the EI treatment increased the gum yield of trees by an average of 4.4 times. The highest gum yield (29.33 g/tree) was obtained with EI at 10% in the Kuh-e Birk habitat, while the lowest yield (3.33 g/tree) was observed in the control treatment of the Mirabad habitat. In total, 39 compounds were identified in the EOs and α–pinene was found to be the predominant compound in all samples (66 to 91.8%). Other compounds such as β–pinene, camphene, sabinene, cis-limonene oxide, neo-iso-verbanol, ρ–cymene and ρ–cymenene were identified in the EOs. EI treatments did not have a significant effect on EO components and the amount of α–pinene and β–pinene in EI 30% treatment increased slightly. Due to the desired quantity and quality of gum in the EI 10%, this method of exploitation can replace the traditional method.