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Rosehip (Rosa canina L.) is an important medicinal, and ornamental plant species with high commercial value. Its sugars, phenolics, organic acids, water-soluble vitamins, and mineral contents composition varies depending on environmental conditions and genetics. The plant is also used as a perfect rootstock for many rose cultivars. Seed proliferation is extremely difficult because of multiple endogenous and exogenous dormancy factors. There is a need to breed standard rosehip cultivars rootstock developments with desired characteristics and outperforming yields in fields. The study aimed to break the seed dormancy of rosehip under in vitro conditions by application of multiple strategies in an efficient manner. The seeds were treated with different doses of GA₃, scarified mechanically, stratified on agar solidified MS medium containing GA₃ singly or in combinations of the two each or three treatments, and subjecting them to the regulated physiological treatment of alternating warm/chilling and cold/dark treatments in parallel for 21 d ensued by 18 d warm/light treatments. It was noted that the rosehip seeds could be germinated variably if the scarified seeds were stratified on agar solidified MS medium with or without GA3. Optimum seed germination (80.00- 85.00%) was noted when the three treatments were combined and the seeds were subjected to regulated and alternating warm and chilling treatments for 21 d leaving them for 18 d in warm/light. These results are very important and could be utilized in breeding and multiplication programs to develop new rosehip fruit and rootstock cultivars.

Plants need different macro and micro nutrient elements to grow and reproduce. Their malnutrition results in unhealthy growth. The soils of Naqadeh area, Iran are deficient in micronutrient elements. The aim of the study was to evaluate the effects of micronutrients application on some qualitative and quantitative parameters of economically important monogerm sugar beet cv. Sonja. The plants were foliar sprayed with iron, boron, zinc, and manganese. The studied traits were potassium, sodium, nitrogen, extraction coefficient, sugar percent, recoverable sugar, alkalinity, molasses, root yield, and white sugar recovery yield. The effect of micronutrients was significant on all studied traits. The highest extraction coefficient of 89.31 was related to the foliar application of iron (Fe) and the highest recoverable sugar percent (16.91%) was obtained from Zn application. Also, the highest mean root yield (74.120 t ha-1) and white sugar yield (12.137 t ha-1) were noted after foliar treatments of boron (B) and Fe, respectively.

Drought stress limits yield severely in most of the crops. Plants utilize complex gene regulation mechanisms to tolerate water deficiency as well as other abiotic stresses. MicroRNAs (miRNAs) are a class of small non-coding RNAs that are progressively recognized as important regulators of gene expression acting at post-transcriptional level. miR408, conserved in terrestrial plants, targets copper related genes. Although, expression level of miR408 is influenced by various environmental factors including drought stress, the biological action of miR408 is still unclear. To examine the miR408 function upon drought stress in chickpea, transgenic lines overexpressing the miR408 were generated. Induced tolerance was observed in the plants with enhanced miR408 expression upon 17-day water deficiency. Expression levels of miR408 target gene together with seven drought responsive genes were measured using qRT-PCR. Here, the involvement of miR408 in drought stress response has been reported. The overexpression leading plantacyanin transcript repression caused regulation of DREB and other drought responsive genes. (C) 2014 Elsevier B.V. All rights reserved.