Journal of Nuts
Volume:10 Issue: 2, Summer-Autumn 2019

Pistachio suffers from some physiological disorders such as fruit abscission, endocarp lesion, blankness, non-split, early-split and deformed nuts. In this experiment, the effects of calcium nitrate (2 gr/lit), calcium chloride (2 gr/lit), boric acid (200 ppm) and their combination treatments were investigated on physiological disorders of ‘Kaleh-Ghoochi’ pistachio. Foliar application was applied one week earlier and two weeks later than full bloom. Then, physiological disorders and enzyme activities, such as catalase (CAT), poly phenol oxidase (PPO), peroxidase (POD), phenylalanine ammonilyase (PAL) and total phenol level of nut-shells and proline level of leaves were tested. Results specified that all applied treatments diminished fruit abscission. Also, all treatments, excepting boric acid, diminished endocarp lesion and non-split nut disorders but there were no considerable differences between the treatments. Results specified that all applied treatments decreased the blank nut but there were no considerable differences between the treatments. In this research, the lowest deformed nuts with 10.38 percent and early split nut with 2.48 percent were observed by application of both calcium nitrate and boric acid. Meanwhile, the highest split nuts with 56.55 percent were obtained by application of calcium nitrate and boric acid. Generally, all treatments especially use of both calcium nitrate and boric acid diminish the catalase, poly phenol oxidase, peroxidase, and phenylalanine ammonilyase enzymes activities and moreover total phenol of nut-shells and proline of leaves.

Roasting is among the most common methods of nut processing causing physical and chemical changes and ultimately increasing overall acceptance of the product. In this research, the effects of temperature (90, 120 ,and 150°C), time (20, 35 ,and 50 min) ,and roasting air velocity (0.5, 1.5 ,and 2.5 m/s) on gravimetrical properties of pistachio nuts and kernels including unit mass, true density, ounce, uniformity, size and shell percentage were investigated.  Gravitational characteristics were measured by experimental and image processing methods. Artificial neural network method was used to predict the relationship between characteristics obtained from experiments and image processing. Volume, unit mass and true density for pistachio nuts were in a range of 1.06 – 1.24 mm3, 0.92 – 1.08 g and  866.01 - 871.35 kg / m3, respectively and they were0.61-0.77 mm3, 0.53 - 0.67 g and 862.21 - 871.29 kg / m3  for pistachio kernels. Number of pistachio nuts was found to be 29-32 per ounce and 102-109 per 100 grams. Uniformity of pistachios was in a range of 1.24-1.50 and their average kernel ratio was higher than 50%. Thus, it can be said that, they were of superior quality. Shell percentage of pistachio nuts was in a range of 38.24–41.98%. Results of the study revealed that ,artificial neural network could properly predict volume and mass of pistachio nuts, but, it had not  appropriate ability to predict apparent density.

In the current research, the effects of some organic fertilizers as fulvic and humic acids on the vegetative growth of pistachio seedlings in a semi-hydroponic culture containing Fe-EDDHA (as a synthetic fertilizer) and FeSO4 (as an inorganic fertilizer) were investigated. The alkalinity is recognized as a main problem in pistachio orchards, therefore the pH of nutrient solution was adjusted to 7.5 and 8.5 (as two alkaline pHs) versus 6.5 (as the optimum pH of hydroponics) in this study. Plants were treated for 9 months under greenhouse conditions. The results demonstrated that the organic fertilizers (especially humic acid) reduced plant growth in acidic condition (pH 6.5). It can be related to precipitation of humic acid under acidity and thereby removing some essential elements for instance Fe form plant growth medium. In contrast, humic substances increased plant growth up to 2.3 times under alkalinity. The analysis indicated that these organic-stimulants can improve plant growth under alkaline conditions by increasing Fe content to about 2 times in pistachio seedlings, especially in shoots. It was noted that this result was somewhat similar in plants grown in media containing Fe-EDDHA and FeSO4. In addition, environmental and economic importance of the application of humic and fulvic acids makes them proper candidates to substitute synthetic fertilizers for agricultural improvement under alkalinity.

Cold is an environmental factor limiting the growth and yield of agricultural crops. To find cold-tolerant pistachio rootstocks, a factorial experiment was conducted at Pistachio Research Center (PRC), Rafsanjan, Iran during 2017-2018. The factors included six rootstocks (Badami Zarand, Ghazvini, Sarakhs, Integerrima × Badami Zarand, Integerrima × Ghazvini and Integerrima × Sarakhs) and four thermal treatments (4, 0, -2, and -4°C) with three iterations. Seedlings in 6-8 leaf stage were placed in thermal treatments for two hours. Ionic leakage, pH of leaked solution, chlorophyll fluorescence, photosynthesis efficiency index, chlorophyll (a, b, total) and carotenoid contents were the traits assessed in this study. Based on the results, a decrease in temperature made an increase in ionic leakage rate, conversely making decreases in pH of the leaked solution, photosynthetic pigments contents, Fv/Fm and PI index. In addition, the highest photosynthetic pigments, pH of leaked solution, Fv/Fm and PI index were observed in Ghazvini and Integerrima × Ghazvini rootstocks. Meanwhile, the highest ionic leakage was observed in Integerrima × Badami Zarand. In aggregate, Ghazvini and Integerrima × Ghazvini were identified as the most cold-tolerant rootstocks, while Integerrima × Badami Zarand was the most cold-sensitive rootstock.

In this study, the effects of coatings made of chitosan (Chi) incorporating thyme essential oil (TEO) on lipid oxidation and changing color indexes of walnut kernels were investigated. Chi: pure, in accompany with TEO at concentrations of 500 and 1000 microliter per liter, in an aqueous coating solution, with different packaging Gunny sack, polypropylene and active packaging, compared with control walnut, were used and stored at 4ºC and 25ºC. The study was performed as factorial experiment based on a complete randomized design. The results showed that amounts of color indexes in treated samples decreased. The samples stored at 4°C contained minimum moisture fluctuations in all packaging methods. The peroxide values and conjugated diene values at 4°C were lower than those at 25°C. Treatments did not have positive effect on free fatty acids of walnut kernels. During the storage, shelf life of walnut kernels prolonged with active packaging and chitosan coating at 4ºC.

The study was conducted to evaluate the pomological attributes and chemical composition of 35 pistachio (Pistacia vera L.) genotypes, including fifteen wild-types and twenty of the important cultivar pistachios from Iran. The results revealed that cultivar pistachios in terms of important characters such as the split nuts (78.57%), blank nuts (6.96%), 100-nuts weight (118.86 g), and size (20.84 mm) were superior to wild cultivars. Higher percentages of the split nuts were observed for ‘Akbari’ genotype (92.81%), and the lowest rate of blank nuts was observed in ‘Fandoghi 48’ (2.84%). Pistachio kernel is rich in nutrients which is almost the same in wild and cultivar genotypes. The mean N, P, K, Mg, Ca, Na, Fe, Zn and Mn values of the pistachio kernels studied were 3.39%, 0.52%, 0.88%, 0.14%, 0.27%, 0.08%, 33.20 μg g-1, 22.40 μg g-1 and 7.38 μgg-1, respectively. The ranges of protein and oil content were 13.70-23.63% and 45.81-55.49%, respectively. According to the results, there was a considerable difference in physical and pomological properties among wild and cultivar pistachio nuts, while there was less difference in oil content and nutrition quality between them.

Pistachio green kernel, is obtained by removing the red testa of around the whole kernel. In this study, the suitable peeling conditions for removing the testa of the kernel were determined using hot water in five termperature levels of 75, 80, 85, 90, and 95°C and diffetent hot water immersion times of 2, 4, 6, 8, and 10 minutes in riped and unripe samples. Quality factors including the number of pistachio green kernels with remained red testa, free fatty acids, and peroxide value were measured at 3 and 6 months after peeling. Sensory evaluations (including appearance, color, taste, and texture) of the best treatments from the previous stage, were measured by 10 trained panelists. Peeling performance were not good using temperatures of 75 and 80°C in both riped and unripe samples. Peeling performance of 100%, was obtained at 85 and 90°C (6, 8 and 10 min) and 95°C (2, 4, 6, 8 and 10 min) kernel immersion in hot water in riped and unripe cultivars. The qualitative factors, free fatty acids and peroxide value, has have increased in both riped and unripe samples during storage. After 6 months of storage, the lowest peroxide value was observed at 90°C (10 min immersion in hot water) and 95°C (2, 4, 6, 8 and 10 min immersion in hot water). The minimum free fatty acid, was observed in riped ripe samples at 90° C (10 min immersion) and in the unripe samples at 95°C (2 and 4 min immersion). According to the comments of trained panelists, the significant differences between treatments were not observed in terms of the sensory characteristics such as taste, texture, color, and appearance at 5% level. In general, with respect to the performance of peeling, free fatty acids, peroxide value, and sensory evaluation, temperature of 95°C (2 min kernel immersion in hot water) can be used for peeling of riped and unripe samples.

In this study, seven walnut populations (Rabor, Hanza, Sardoueih, Dalfard, Bidkhan, Dehbakri, and Baft) were selected from Kerman province and compared for drought stress tolerance. Water potential between 0 and -1.5 MPa was obtained by polyethylene glycol 6000 solutions. Germination percentage, leaf relative water content (LRWC), and growth parameter of seedlings diminished with increasing drought stress, but it varied across the genotypes. The Dehbakri genotype was the most tolerant to osmotic stress. In contrast, Dalfard and Bidkhan were the most sensitive to osmotic stress in which no germination occurred at -1.5 MPa. Additionally, drought treatment increased proline and soluble sugar content in the shoot and root in the tolerant genotypes. These results suggest that the accumulated proline and soluble sugar promote drought stress. Overall, the concentration of phosphorus, potassium, calcium, magnesium, and manganese increased with a reduction in the water potential while nitrogen, copper, zinc, and iron elements dropped with the decrease in water potential. Using cluster analysis, Dehbakri was classified as the most tolerant genotype. Baft, Sardoueih, Rabor, and Hanza were semi-sensitive genotypes; finally Dalfard and Bidkhan were classified as the most sensitive genotypes. For future production of drought tolerant rootstock, Dehbakri genotype is suggested to be used in breeding programs.