جستجوی مقالات مرتبط با کلیدواژه "روغن ولک" در نشریات گروه "زراعت"

Olive (Olea europaea L.) is an evergreen tree and one of the most important products of the horticultural section in Iran due to high nutritional value of its oil and fruits. Adaptation of olive cultivars to the climatic conditions of different regions are not the same. The results of studies showed that special cultivars are recommended for each region. In tropical and subtropical climates with mild winter such as Ahvaz, the chilling requirement of olive trees is not completed. This condition has led to poor and insufficient flowering in some olive cultivars. Mineral oils, including volck oil are one of the most beneficial treatments to complete chilling requirement and bud break in fruit trees. The aim of this study was to investigate the response of two olive cultivars (Manzanilla and khaziri) to the application of volck mineral oil and studying their flowering and biochemical characteristics in Ahvaz condition.

In this experiment, the effect of volck mineral oil spraying [control (water spray), 1, 3, 5 %] on two olive cultivars were investigated. The experimental design was split plot arranged in complete block design with four replications. Measured traits included flowering characteristics such as the number of inflorescences in the branch, flowers in inflorescence, complete flowers, flowering days after treatments, percentage of flower fall, fresh and dry weight of flower and inflorescence. Biochemical properties such as bud carbohydrates and ABA, leaf proline and chlorophyll were measured.

The results showed that foliar application of 3 and 5 % volck oil caused flowering (31.8 and 28.7 days after treatment, respectively) in Manzanilla cultivar. Bud carbohydrate content increased significantly after tree spraying with volck oil in all of three concentrations. The highest content of bud carbohydrates (78.68 mg/g) was obtained in khaziri when treated with 3% volck oil. The use of volck oil was effective in increasing the ABA concentration in Manzanilla cultivar and its effect was as 3 and 5% volck oil (83.1 and 105.4 µg/g, respectively). The amount of proline in both cultivars increased until 60 days after applying three concentrations of volck oil. The levels of chlorophyll a, chlorophyll b and total chlorophyll increased until 30 days after treatment and then were decreased. Volck oil (3%) can be used for flowering of Manzanilla cultivar in climatic conditions of Ahvaz.

Based on the obtained results, it seems that the effect of volck oil on flowering and biochemical traits depends on the type and concentration of mineral oil and type of the cultivar. In the present study, flowering occurred when Manzanilla cultivar treated with mineral volck oil (3 and 5%) and the flowering traits were improved at 3% oil more than other treatments.

Adjuvants through improving the performance of foliar-applied herbicides aim to optimize herbicide rates and minimize their cost and adverse effects. Enhancement in the efficacy of herbicides for effective weed control is of great importance, especially at lower dosage and it could be considered as an approach to reduce application rates of herbicides.Vegetable oils, as one of the adjuvants, have aroused a point of interest because of their less toxicity and risk, eco- compatibility and, natural renewability and biodegradability. The effect of adjuvant types to increase or decrease herbicides efficacy depend on type, characteristics, and formulation of herbicides, weed species, and environmental conditions; therefore to detect appropriate adjuvant for each herbicide, field experiments are required. Thus, the effects of petroleum (volck) and some vegetative oils in combination with nicosulfuron (Cruz) were investigated in this study.

In order to evaluate nicosulfuron efficacy for weed control and the effects on corn yield characteristics when it was applied alone and tank-mixed with petroleum (volck), olive, castor, sesame, bitter almond, and sweet almond comparing to weedfree and weed infested condition, this field experiment was conducted in a randomized complete block design with three replications at a field located at Mahi-dasht, Kermanshah province.

The addition of olive, castor and volck oils were able to decrease density of redroot pigweed, green foxtail and groundcherry, and dry weight of total weeds to the extent of weedfree control. None of chemical management treatments could control orange nightshade and total weeds density as much as weed-free treatment. Orange nightshade showed a high level of tolerance to nicosulfuron. Plant height, biological and grain yield, harvest index, and thousand-seed weight of corn compared to weedfree condition was 22, 41, 59, 30, and 5% for weedinfested, and 13, 8, 10, 2, and 1% for nicosulfuron applied alone, respectively. Tank mixing of all oils wanes height reduction to 7%, olive and castor oils decreased biological and grain yield reduction to 2.5%; although none of them could produce the same as weed free treatment. Corn harvest index and thousand-seed weight, when nicosulfuron applied in combination with olive, castor and sesame oils did not differed significantly from weed free control.

Weed species control improved when nicosulfuron applied with petroleum and vegetable oil adjuvants. Herbicide efficacy enhancement for weed species were different by utilizing various oils. In general, olive and castor oils showed the best results for nicosulfuron efficacy on weeds and corn yield related traits.