Postharvest physiology
Fatemeh Ahmadi; Mohammad Mehdi Sharifani; Amir Mousavi; Negin Akhlaghi Amiri; Mostafa Khoshhal Sarmast; Khalil Zaynali Nezhad
Abstract
IntroductionExternal and internal quality of citrus such as color, shape and taste increase economic benefit. The vigour of each rootstock causes qualitative and quantitative change and the effective factor on commercial maturity, which is important for gardeners and producers. Considering the characteristics ...
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IntroductionExternal and internal quality of citrus such as color, shape and taste increase economic benefit. The vigour of each rootstock causes qualitative and quantitative change and the effective factor on commercial maturity, which is important for gardeners and producers. Considering the characteristics of the fruit in grafted trees, the present research was conducted with the aim of evaluating the effects of trifoliate orange, Citrange and Citrumelo rootstocks on some morphological, phytochemical and molecular traits of ‘Thomson Navel’ orange fruit. Materials and MethodsThis research was carried out in 2018 at Ghaemshahr Horticultural Research Station, Mazandaran. It was conducted in the form of randomized complete block design (RCBD) of uniform and 10-year-old ‘Thomson Navel’ orange grafted on ‘trifoliate orange’, ‘Citrange’ and ‘Citrumelo’ rootstocks with four replications. The samples were collected at the end of October and were transferred to the research laboratory of Horticulture Department, Gorgan University of Agricultural Sciences and Natural Resources for further research. Measurements were made on the morphological traits, quality characteristics of the fruit, the phenolic compounds of the peel and the pulp of the fruit and relative expression of fruit pulp sucrose phosphate synthase1 gene. Data variance analysis was done using SAS software (version 9.0). Mean comparisons were done with Duncan's multiple range test. Results and DiscussionThe results of analysis of variance showed that the rootstock effect on traits of length-to-diameter ratio, weight and density of ‘Thomson Navel’orange was significant at the five percent probability level (p<0.05) and the fruit length and diameter traits were significant at the one percent probability level (p<0.01). The results of mean comparison showed that the characteristics of length, diameter, length-to-diameter ratio, weight and density of ‘Thomson Navel’ orange at commercial maturity on the trifoliate orange rootstock were more than the two other rootstocks. Due to the early harvest, the density of the fruit was recorded lower than one, so that the highest amount (0.5 g per cm3) was observed in the rootstock of trifoliate orange however it was not significantly different from Citrange rootstock. Based on the results of analysis of variance, it showed that the effect of rootstock on total soluble solids was significant at the level of five percent. Also, the rootstock had a significant effect on titratable acidity, taste index, vitamin C, acidity, EC and total sugar at the level of one percent. However, the amount of vitamin C was higher in the Citrumelo rootstock. The highest amount of acidity and EC belonged to trifoliate orange rootstock and the lowest amount belonged to Citrange rootstock. The highest amount of total sugar was observed in the dwarfing trifoliate orange rootstock, while its lowest amount was recorded in the vigorous Citrumelo rootstock. The highest amount of total soluble solids was observed at the rootstock of the trifoliate orange. The amount of titratable acid in the Citrange rootstock was higher than the other two rootstocks. The taste index was higher in the trifoliate orange rootstock than the other rootstocks. According to the results of analysis of variance, the rootstock effect on the index of total phenol of fruit peel and pulp and total flavonoid of fruit peel was significant at the five percent probability level (p<0.05) and only on the antioxidant activity of the fruit peel at the statistical level of one percent (p<0.01). Also, there was no significant difference in total flavonoid traits and antioxidant capacity of fruit pulp. The highest amount of total phenolic, total flavonoid and percentage of antioxidant activity was found in the trifoliate orange rootstock. Also, between the fruit organs, phenolic compounds were recorded more in the fruit peel compare to the fruit pulp. The peel of orange is more exposed to ultraviolet rays and changes in environmental conditions, Therefore more secondary metabolites accumulate in that part of the plant. The highest relative expression of fruit pulp sucrose phosphate synthase1 gene was obtained in the Citrange rootstock. ConclusionThe vigor of different citrus rootstocks caused the dwarf trees to have a higher accumulation rate of phytochemical indices than the vigorous trees. The trifoliate orange rootstock is suitable for fresh consumption due to the early commercial maturity of the fruit. Fruit peel rich in phenolic compounds is used for medicinal purposes. The technical knowledge from this research will be useful for citrus producers in East Mazandaran.
Growing vegetables
Majid Amiri roudan; Mohammad Reza Hassandokht; Davood Sadeghzadeh-Ahari; Amir Mousavi
Abstract
Introduction
The use of natural and artificial mulches to reduce evaporation from the soil surface and retain moisture is one of the best measures to make optimal use of limited water resources and increase crop yields. Optimal production of plants in sandy soils has been challenged due to their ...
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Introduction
The use of natural and artificial mulches to reduce evaporation from the soil surface and retain moisture is one of the best measures to make optimal use of limited water resources and increase crop yields. Optimal production of plants in sandy soils has been challenged due to their low capacity in water retention and also production of plants in arid and semi-arid regions due to water shortage and drought stress. Water scarcity is increasing as a result of global warming, and attention is being paid to the methods that lead to water storage. Therefore, it is necessary to increase water consumption efficiency with new technologies. One of the new methods of water retention in the root zone is the use of a water retaining layer below the soil surface. By preserving water and elements in the root zone and creating a stable environmental state, it increases local production and economy by reducing soil erosion and groundwater pollution. Also, due to limited water resources, it is necessary to seek solutions to conserve water and increase water use efficiency. Mulch is considered as one of the best ways to retain water in the soil and reduce soil evaporation. Therefore, in this study, the application of impermeable soil layer on morphophysiological and biochemical traits of eggplant (Solanum melongena L.) was investigated using date leaf mulch under deficit irrigation stress.
Materials and Methods
This study was conducted in Roudan, Hormozgan, Iran. Main plot includes deficit irrigation stress in three levels (100, 70,40 % of plant water requirement), sub-plot includes mulch in two levels (date leaves and no mulch) and sub-sub-plot includes impermeable layer in three levels (0, 100, 120 cm). Eggplant seeds of the local variety Rudan were planted in the seedling tray and transplanted when the seedlings were about 15 cm long or 5-6 leaf stage. Shortly after transplanting the seedlings to the field, daily irrigation was performed. CROPWAT software was used to calculate 100 % of the water requirement. Stress was applied using drippers with lower flow rate or reduced irrigation hours and by installing water meters.
Results and Discussion
The results showed that the highest plant height (78 cm) belonged to date palm mulch, layer impermeable at depth of 120 cm and 100% water requirement. The use of date palm mulch and impermeable layer, especially the impermeable layer, has led to an increase in the number of leaves and fruits in the eggplant. The highest number of leaves (189) belonged to the treatment without mulch and with an impermeable layer of 120 cm soil depth in 100 % water requirement and the lowest (75.13) belonged to the treatment without mulch and impermeable layer in 40 % water requirement. The highest number of fruits belonged to the treatment without mulch and impermeable layer at depth of 120 cm and 100 % water requirement and the highest amount of dry matter (12.5%) belonged to the treatment of date palm mulch and impermeable layer at depth of 120 cm and 100 % water requirement and the lowest (1/9%) belonged to date palm mulch without impermeable layer and 70% water requirement. The results showed deficit irrigation stress reduced the amount of chlorophyll a, b and total in eggplant. The use of date palm mulch and impermeable layer in water requirement of 70 and 40 % has increased the amount of chlorophyll, which seems to be used in case of water shortage, reduce the adverse effects of dehydration and prevent the destruction of chlorophyll in eggplant. The highest amount of total chlorophyll belonged to the 100 % water requirement, without the use of date palm mulch and impermeable at depth of layer 120 cm. The highest amount of proline in this study belonged to treatment without date palm mulch, application of impermeable layer at depth of 0 cm and water requirement of 40 % and the lowest belonged to the treatment of date palm mulch, application of impermeable layer at depth of 120 cm and 100 % water requirement. The highest amount of eggplant water use efficiency was obtained in 40 % water requirement, use of date palm mulch and impermeable layer at depth of 120 cm. The results of this study also showed that deficit irrigation stress reduced fruit yield in eggplant and the use of date palm mulch and impermeable layer also increased eggplant yield. This increase in fruit yield is especially noticeable in the use of date palm mulch and impermeable layer at depth of 120 cm.
Conclusion
It seems that the impermeable layer and date palm mulch have reduced the negative effects of water stress on the plant, increased fruit yield and water use efficiency and reduced the effects of stress.
Maryam Karimi Alavijeh; Ali Ebadi; Amir Mousavi; Alireza Salami
Abstract
Chilling is an important environmental stress that influences the yield and quality of many agricultural crops. Different plants use different systems to endure this stress and minimize its effects. One of these systems is enzymatic reaction. To find out more about responses of different grapevine species ...
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Chilling is an important environmental stress that influences the yield and quality of many agricultural crops. Different plants use different systems to endure this stress and minimize its effects. One of these systems is enzymatic reaction. To find out more about responses of different grapevine species and cultivars to the low temperature conditions, their enzymatic changes were evaluated in a factorial experiment based on randomized complete design with 3 replication during different periods after chilling stress. Leaf samples of plants under cold stress had been taken and maintained in -80 °C until enzyme extraction. Low temperature around 4 °C is sufficient to induce genes that produce chilling acclimatization proteins. In the present study, leaf samples were collected from the plants that were kept at 4 °C during different time intervals, and then total proteins as well as two main antioxidant enzymes (catalase and guaiacolperoxidase) activities were measured. Results showed that as temperature decreased, enzymatic activities were increased in six Iranian grapevine cultivars (‘Atabaki’, ‘Khalili-Danedar’, ‘Shahroodi’, ‘Rajabi-Siah’, ‘Askari’ and ‘Bidane-Sefid’) as well as ‘Riparia’, an American species. The highest enzymatic activities of catalase and ceroxidase were recorded in ‘Khalili-Danedar’ and ‘Riparia’. However,the lowest activities were recorded in ‘Rajabi-Siah’, ‘Bidane-Sefid’ and ‘Shahroodi’. For all studied cultivars, peroxidase showed its highest activity at 12 h after chilling stress, then remained constant, while, the highest activity of catalase were recorded at 8 h. In addition, cold stress increased the total protein content for all studied cultivars, in which ‘Khalili-Danedar’ had the highest protein content amongstudied cultivars. Also, the highest proteins content were recorded at 12 h after exposing plants to cold.
