نشریه تولیدات گیاهی
سال چهلم شماره 3 (پاییز 1396)

Apple is one the most important horticultural crops in Iran. As the most apple cultivars are self-incompatible, having a good fruit set requires favorable cross-pollination. However, this phenomenon is related to a series ofcomplex processeswhich happens on thestigma. Zinc is one of the main factors that affects pollination and has an important role in increasing the percentage of pollen germination thereby increasing fruit set. It has been reported that zinc is referred to be as a main growth element because of its role in hormone production in buds specially auxin biosynthesis. Auxin is the most important hormone which affects pollen tube penetration to the style and so, fruit set in plants. Zinc deficiency in the apple orchards primarily affects the above ground portions of trees, resulting in poor leaf and shoot growth, reduced flowering and fruit set, and reduced size and coloring of fruit. Zinc is also important in the movement of calcium within the tree. Using zinc sprays is the most consistent and cost effective way to apply this element in apple tree orchards.
In this research, the effect of zinc solution in three levels (0, 3000 and 5000 mg.l) was studied on pollen penetration to the ovary in the crosses among four apple cultivars including Golden Delicious, Red Delicious, Gala, Fuji. Pollen penetration was studied 72 and 120 hours using fluorescent microscopy technique in the laboratory after field pollination. Crosses among the cultivars included 1- ♀Red delicious × Golden delicious♂, 2- ♀Galla × Fuji♂, 3- ♀Red delicious × Fuji♂, 4- ♀Golden delicious × Fuji♂ and ♀Golden delicious × Galla♂.
Results showed that the effects of zinc, crosses and their interaction were significant on pollen germination and tube penetration in the primary, middle of the stigma and top of the ovaries. The highest percentage (59.4%) of germination on the stigma was observed in the cross (♀Golden Delicious × Gala ♂), in 120 hours and the highest penetration of pollen tube in ovary (18.08%) was observed at the cross point of 5000 ppm of Zinc, in 120 hours respectively.
In this research the foliar application of Zinc (until 3000 mg.l) increased pollen germination and tube growth on the stigma in all of the studied four apple cultivars. Although, increasing zinc concentration to 5000 mg.l showed negative effects on the both characteristics which showed the tolerance range of the cultivars to the zinc concentration based on their genetic traits. However, increasing the Zinc concentration to 5000 mg.l led to increased pollen tube growth and penetration to the different parts of the styles in all of the crosses linearly.

The symbiotic relationship between arbuscular mycorrizae and plants can improve plant growth by increasing mineral nutrient absorption, tolerance to diseases and stresses such as drought, temperature fluctuation, metal toxicity, salinity and other adverse conditions. Micro propagation of potato by micro and mini tubers have been established for improving multiplication rate and possibility of reserving some more stock plants as germplasm. Multiplication of the minitubers already has been accompanied by lower establishment that causes low vigor and performance of the plant especially in water stress conditions. This experiment was done to study the effect of arbuscular mycorrhiza fungus inoculation on vigor and performance of planlets derived from minituber in green house conditions.
Material and This experiment was conducted as factorial based on a randomized complete design with four replications. The treatments were irrigation levels (100%, 85%, 75% and 65% of field capacity) and two levels of culture medium inoculation (inoculation with Rhizophagus irregularis and non- inoculation). The amount of water supplement was evaluated according to their treatment by weighing the boxes and calculating the amount of field capacity base. The method described by Gonigle et al (1990) was used for root colonization assessment. Mini-tuber obtained from any plant was weighed, arranged in three groups. Two-way analysis of variance (ANOVA) was carried out using SAS software (v. 8.02, SAS Institute, Cary, NC).
Analysis of variance showed that in all minitubers the main effects of incubation with mycorrhiza, irrigation levels and their interaction were significantly different (p≤0.05). Minituber dry matter percentage showed a significant difference (p≤0.05) with mycorrhizal inoculation and interaction between mycorrhiza and irrigation levels. Means comparison showed that generally more minituber production in different sizes was accomplished by mycorrhizal treatments in all irrigation levels in comparison with non-inoculated ones. The most minitubers in different sizes were accomplished with inoculated and providing 85% FC water treatment. Inoculation of minitubers in 65% and 75% FC of irrigation levels did the same as the competitive situation with non-inoculated miniturbers in 85% and 100% of irrigation at the most traits related with quantity and quality of minituber production.
It is concluded that although mycorrhiza was able to promote growth and final yield of minituber production and multiplication rate, this ability is not limited and can be extended ultimately by critical threshold of water accessibility. Dry matter of minituber was affected by application of mycorrhiza in four irrigation regimes. In relation with minituber dry matter, it is conceived that mycorrhiza can affect the dry matter of minituber but irrigation levels must be remarkable in this situation. Generally, it is concluded that mycorrhiza had considerable effect on performance of planted minitubers by adjustment of water stress through promoting mineral nutrients absorption and increasing osmotic potential capability. This ability could be different with intensity of water deficiency.

Any improvement in agricultural system that results in higher production should reduce the negative environmental impact of agriculture and enhance the sustainability of the system. Seaweed extracts (SWE) are known to cause many beneficial effects on plants as they contain growth promoting hormones, trace elements, vitamins and amino acids. Humic acid plays a vital role in soil fertility and its application increases the plant growth and nutrient uptake. The present study was undertaken to investigate the effect of SWE, humic acid and chemical fertilizers on the morphological and biochemical characteristics of Trigonella foenum-graecum L.
Material and The experiment was carried out in 2016 at the Agricultural Research Greenhouse at Imam Khomeini International University, Qazvin, Iran. The experiment was based on a completely randomized design with four treatments including: SWE, humic acid, chemical fertilizers and control and 7 replications. The pots were filled with 5kg of farm soil, which was evenly mixed with recommended level of chemical fertilizers (N; 0.08, P; 0.06 and K; 0.1 g/kg soil) for chemical fertilizer treatment. Seeds were sown at a depth of 1.5 cm in each pot. Seedlings were thinned to five plants per pot 10 days after emergence. In 4 leaves, appearance stage, SWE and humic acid treatments were applied as a foliar spray every 14 days, for three times before harvesting. Growth parameters were measured in correct time. The biochemical constituent pigments such as chlorophylls and carotenoids and also total ascorbic acid in leaf were estimated in control and treated plants using standard methods. Dried seeds of Fenugreekwere subjected to hydro distillation for 3h using a Clevenger-type apparatus to produce oil and essential oil percentage was measured.
In relation to the mean comparisons, the maximum shoot length and the highest number of pods per plant was obtained in plants receiving SWE and NPK. Maximum plant fresh and dry weights were observed in plants received SWE. All fertilizer treatments increased the number of seeds per pod but there were no significant differences between the treatments. The highest chlorophyll b, total chlorophyll contents, total carotenoids, ascorbic aicd and essential oil percent were obtained in plants that received SWE.
Foliar application of seaweed extract fertilizer on fenugreek plants significantly increased all the examined growth parameters of the plants compared to the control. These results agree with previous studies where growth and plant vigor of dill, coriander and fenugreek plants were enhanced by seaweed extracted treatment. Seaweed extracts create equilibrium in growth as a result of the present auxins which will increase vitamins and hormones produced in the treated plants. Results showed that treatments had a significant effect on total chlorophyll, chlorophyll 'a' and 'b', total carotenoids and essential oil content of fenugreek. Seaweed extracts contain cytokinins as well which induce the physiological activities and increase the total chlorophyll, carotenoids and ascorbic acid in the plant.

Wild oat was described as a vigorously growing weed with a capability to attain greater height, and establish and develop extensive leaf area and horizontal branches when moisture and nutrients are not limiting. Fertilization is an important agronomic strategy used extensively to increase crop yield. Although, the effect of fertilizers is extensively investigated in wheat, there is little information to assess the effect of fertilizer application on wheat yield loss due to wild oat interference. The objective of this study was to investigate the wheat yield loss caused by wild oat interference at nitrogen different levels.
In order to evaluate the wheat yield loss caused by wild oat interference at different nitrogen levels, a field experiment was conducted at a farm in Ramhormoz city (latitude 31.16°N, longitude 49.36°E and 151 m asl), south-west of Iran in 2011-2012. The experiment was designed as a randomized complete block with a split plot arrangement with nitrogen fertilizer (N0: unfertilized control, N1: the use of 150 N Kg ha-1 before wheat seeding and N2: the use of 50 N Kg ha-1 before wheat seeding 100 N Kg ha-1 at late tillering stage of wheat) as the main plot and wild oat density (D0: weed- free control, D1: 25, D2: 50, D3: 75 and D4: 100 plants m-2) as the subplot with three replications.
A hyperbolic function was used to describe yield loss-density relationship. Increasing wild oat density had asymptotic-type effect on wheat yield loss. Initial slope (i) of the rectangular hyperbola model was a significantly greater when nitrogen fertilizer was applied. Moreover, for the rectangular hyperbola model, there was significant effect of nitrogen application on estimated maximum wheat yield loss (A). Application of 150 N Kg ha‑1 (N treatment) before crop seeding resulted in a greater competitive ability of wild oat than other treatments.
The results of this study suggest that the application of nitrogen fertilizer increases wild oat competitions when wheat fields infest with wild oat. Although the wheat yield loss was increased by N application, a such reduction was more recorded at N application than multistage-applied N. Greater knowledge of the effect of N on weeds and crop grown in competitive mixtures may allow a better understanding of why differences occurred among previous studies and aid development of fertilization strategies to reduce weed competition with crops.

Organic fertilizers are carbon-based compounds that increase the productivity and growth quality of plants. Municipal waste compost is an organic manure that improves the physical, chemical and biological properties of soil and adds organic matter and exerts a positive effect on elements absorption, quality and yield of saffron. In addition, in saffron cultivation, it is possible to produce considerable amounts of stigma by using of standard mother corms with a minimum weight of 8 g. Therefore, the aim of this research was to investigate the interaction effects of municipal waste compost and mother corm size on chemical properties of saffron.
This experiment was conducted with a factorial arrangement based on randomized complete block design with three replications at the Agricultural Research Station, University of Birjand during the growing season of 2014-2015. Treatments were four levels of municipal waste compost (0, 5, 10 and 20 t.ha-1) and three mother corm weights (0.1-4, 4.1-8 and 8.1-12 g). Flower of saffron was measured during autumn of 2015. Total phenol was determined using the Folin-Ciocalteu assay. Free radical scavenging activity of the samples was determined using DPPH method. Secondary metabolites of saffron (crocin, picrocrocin and safranal) were measured according to Iran’s national standard.
The results showed that the highest total phenol and antioxidant activity (10.0789 mg.100 gr-1 and 65.66%, respectively) was obtained in treatment 20 t. ha-1 compost and the lowest (10.0785 mg.100 gr-1 and 62.58%) was recorded in control. Results showed that addition of the compost rate significantly increased secondary metabolites (crocin, picrocrocin and safranal). So, corm weight had a significant effect on antioxidant activity and the main secondary metabolites and the highest characteristics were obtained for corm with 8.1-12 g. As, the effect of interaction of municipal waste compost and corm weight significantly affected the main secondary metabolites.
The results showed that fertilizer treatment and corm weight influenced chemical properties and the main second metabolites of saffron positively. It has been reported that plants cannot simultaneously allocate resources to growth and defence and that there is competition between proteins and phenolics in plants for the common precursors involved in their biosynthesis .These results led us to presume that saffron plants may utilise benefits from compost fertilizer for their protein synthesis and growth development. On the other hand, organic matter (e.g. compost) acts as precursors or activators of phytohormones and growth substances and secondary compounds in plants. The type of soil and the content of organic compounds in soil can have a decisive effect on increasing the content of organic compounds in soil and strengthening antioxidant activity.

Tomato (Solanum lycopersicum Mill) is one the most important economic crop in the world and Iran. Broomrape is the main constrain of tomato production. Some Orobanche species such as O.cumana or O. crenata are specialist in parasites of a small group of genera or species, while others have a much broader spectrum of hosts as is the case of O. ramosa. The available control methods have not proven to be as effective, economical and applicable as desired; thus, the only way to cope with the weedy root parasites is through an integrated approach, employing a variety of measures like resistant cultivars, plant probiotics and allelopathic plants in a concerted manner.
Hence the aim this study was to determining the susceptibility of various cultivars of tomato to infection by O. ramosa and effect of allelopathic hairy vetch and plant probiotics on reducing the O. ramosa invasion. Greenhouse experiment was conducted in the greenhouse of Campus of Agriculture and Natural Resources, Razi University, Kermanshah, Iran in 2016. Treatments were different tomato cultivars including Karoon, Aras, Super strain-B and Sivand, allelopathic hairy vetch cluster, bacteria isolates, including INR7, P2, and E11. The soil of each pot was contaminated with 20 mg seed of O. ramosa. At the termination of the experiment, the number and weight of tomato fruits, dry weight of roots and aerials parts of tomato plants were recorded.
Our results showed that although the Sivand was the most susceptible cultivar to O. ramosa infection, Karoon cultivar had the highest to levace to branched broomrape. Results of present study revealed that broomrape biomass was positively correlated to decreased tomato biomass. The presence of allelopathic plant hairy vetch increased tomato weight in presence of branched broomrape. The use of probiotic P2 increased the number and weight of tomato in the presence of O. ramosa, while it had no effect on infection of O. ramosa. However, only INR7 probiotic had some inhibitory effect on branched broomrape infection.
Totally hairy vetch had a significant effect on reducing of O. ramosa infection (up to 100% control). Based on these results, it could be concluded that plant probiotics only increase tomato yield without any dirrectly effect to broomrape residues of hairy vetch probably by releasing allelochemical redused orobanche germination infection