Journal of Nuts
Volume:12 Issue: 1, Winter 2021

The rate of pistachio export in Iran has decreased since 2010 onwards while the United States exports has risen sharply at the same time period. Thus, the present study aimed to investigate the factors which may affect negatively on exports of Iran’s pistachio. For this purpose, the macroeconomic variables and pistachio exports data of the desired period were used. Autoregressive distributed lag (ARDL) model was used for this study. The results indicated that economic growth, appreciation of the exchange rate and bank facilities remained positive and had significant effect, while liquidity growth has a significant negative effect on pistachio export. The coefficient of ECM (-1) for pistachio is -0.0642. The low amount of error correction coefficient indicated the low rate of adjustment in pistachio exports. Only 6% of the imbalance error of pre- period adjusted in each period. Therefore, solely relying on short-run policies will not be beneficial. Based on the obtained result, it is recommended to provide financial resources for pistachio producers and exporters, domestic liquidity should be directed toward productive economic activities, domestic inflation should be deflated and adjusted with exchange rate and real appreciation of the exchange rate, should be considered by improved exchange market management.

The required capital and liquidity for agricultural production are always a limiting factor in Iranian agriculture. Since, income is a combination of production and product price, one of the major problems of the country's pistachio industry is the high yield fluctuations and high price fluctuations. In the present study, the mean and yield fluctuations of four pistachio commercial cultivars (Kaleh-Ghoochi, Ahmad-Aghaei, Akbari, and Owhadi) were evaluated in the Anar and Rafsanjan orchards in Kerman province. The information used in this study was collected through a questionnaire from farmers. The orchards were selected by multi-stage random method. From the total number of villages in the two regions, some sites were selected based on random. Then, some farmers were selected randomly. By referring to the selected farmers, an orchard was selected from each cultivar. The number of studied orchards was 100 forms in each cultivar. To measure the yield per hectare, the amount of actual product that had achieved in the last six years. Finally, the mean and yield fluctuations of 4 pistachio commercial cultivars were analyzed. The results showed that the studied cultivars had a significant difference in the yield, profit net and coefficient variation at a probability level of 5%. The results indicated that the Ahmad-Aghaei cultivar was the best in average yield (1758.7 kg ha-1) and net profit per hectare (292530201 Rials ha-1) and then Akbari cultivar. However, performance fluctuations in the Owhadi cultivar (53.06%) was lower than the other three cultivars. Base on the results, the Kaleh-Ghoochi cultivar was minimum in average yield (1073.6 kg ha-1) and production fluctuations (73.14%) than the others. Therefore, if the aim is to minimize the income fluctuations of pistachio farmers, depending on the region, one of Ahmad-Aghaei or Akbari cultivars should be planted. It can be concluded that among commercial cultivars, prioritization and justification for planting and propagation were Ahmad-Aghaei, Akbari, Owhadi and Kaleh-Ghoochi, respectively.

To increase the amount of export and marketability of walnuts, a quick, cheap and non-destructive sorting approach should be used. The overall objective is to sort the full, half full and empty walnuts relying on fuzzy logic and sound analysis methods. To sort the walnuts the sound processing technique was used. In this regard, effective parameters on sorting and quality such as: size and shape of walnut were studied. For this purpose, 300 dried walnuts were randomly selected from a walnut orchard for use in experiments. An electronic system consisting of a computer, a microphone, and a mechanical section consisting of a sound chamber were designed to measure the sound intensity of a walnut. At this stage, each walnut was released in three directions: back, side and abdomen 30 cm above the surface of the sound chamber. The sounds were recorded by a microphone with acoustic beats on a sound chamber made of wood and a 45-degree slope. The data from the sound signals were stored in the time domain on the computer and then processed by the MATLAB software. In order to eliminate the ambient noise of signals, Kalman filter algorithm was used to achieve high accuracy and fast convergence. Then these data were analyzed by fuzzy logic method. In this research, WEKA software and J48 algorithm have been used to classify walnuts based on their filling and using the features extracted from the walnut collision with a wooden plate. In order to classify walnuts according to the fullness of walnut kernels, a scientific and innovative index called Full Kernel Index (FK) was used.  The results of this study showed that for classification of walnut, decision trees due to simplicity of structure and creation of fuzzy rules and threshold values of membership functions make fuzzy inference system with high accuracy. The final fuzzy model was presented to classify walnut into two classes with 0.087% separation accuracy and 3 classes with 0.080% separation accuracy.

Aflatoxins are secondary metabolites, which have documented in food and feed such as pistachio.Application of incorrect cultural practices such as animal manures resulted in increasing the density of Aspergillus section Flavi propagules and as consequences increase in aflatoxin content in pistachio nuts. Here, the density of Aspergillus section Flavi propagules, aflatoxin kernel content and characteristics of pistachio fruits in soil surface and fertilizer cannel applications of poultry manure in the orchards in randomized complete block design were compared with control treatment (without poultry manure application). Application of poultry manure on soil surface increased Aspergillus section Flavi propagulesby 4.5 and 11 times higher than compare to those treatments either which not received or in fertilizer channels, respectively. Aflatoxin content in pistachio nuts decreased by 85 and 51 % where poultry manures applied in fertilizer channels and no application compared to surface application, respectively. Overall, poultry manure in fertilizer channel reduced the frequency of blank fruits as well as increasing of splitted nuts and the nuts’ sizes.

There are diverse types of gelling agents that are used in media cultures. Agar and Gelrite are among the gelling agents used in DKW culture medium, as the common culture medium for the micropropagation of walnut plants. The effects of these gelling agents have not been investigated on the successful production of in vitro explants and the response of the explants to ex vitro evaporative demand is overlooked so far. Stomata and water relations of tissue culture medium determine the successful production of in vitro plants, therefore this experiment was conducted to investigate the effect of two types of gelling agents (Agar and Gelrite) on the stomatal characteristics, transpiration rate (E), and desiccation responses of in vitro walnut explants. Stomatal morphology, transpiration rate, RWC, and some morpho-physiological traits such as shoot length, chlorophyll content, osmotic potential (ψs), proline, and glycine betaine content were evaluated in micropropagated walnut explants cultured on Agar or Gelrite. Analysis of results indicated no considerable changes in the morpho-physiological characteristics of explants grown in DKW medium containing Agar or Gelrite gelling agents. Compared with the medium containing Agar, adding Gelrite to the DKW medium caused a decrease in E and an increase in relative leaf water content (RWC) of the walnut explant's leaves during desiccation. Gelrite induced generation of more closed stomata leading to a reduction in E and increase in RWC during desiccation. This resulted in improvement of walnut plantlet's capacity to conserve their water content and as the consequence promoted ability to prevent ex vitro wilting.

The Persian walnut (Juglans regia L.) is one of the most valuable crops in Iran. The present study was conducted in The rabor agriculture research station (RARS) in Kerman province to investigate 21 important pomological and phenological variables among 37 walnut native genotypes and commercial cultivars in the year 2020. In general, results showed that walnuts from RARS were phenotypically diverse with the significant variation found across most traits examined. The highest and lowest coefficient of variation (CV) was for kernel percentage (CV= 29.48%), and time of male flowering (CV= 14.77%), respectively. Results also showed a strong positive correlation between nut weight and kernel weight (r= 0.727). The date of nut maturity had the lowest correlation with kernel intensity of  the ground color (r= -0.476). Principal component analysis of variables revealed that the first eight principal components (PCs) accounted for 79.43% of the total variation. Cluster analysis based on variables produced a dendrogram with five main clusters. The grouping of genotypes was not following their geographical origin. This study revealed the presence of high phenotypic diversity in the walnut genotypes of Rabor Agricultural Research Station (RARS), supporting their breeding value for possible use in the future.