mohammadjavad mirhadi

Safflower is an oily plant native to Iran, and at the same time, it has good resistance to drought and salt stress, which is a suitable plant for self-sufficiency in this field due to the lack of oil and the large volume of its import to the country. This research was conducted in order to evaluate three varieties of winter safflower under drought stress conditions in different stages of growth in terms of seed and oil yield and other traits. This experiment was carried out in the form of split plots in the form of a basic design of randomized complete blocks in three replications, the main plots containing five levels of drought stress, respectively: Drought stress at budding stage, Drought stress at the beginning of flowering stage, drought stress in the mid-flowering stage, drought stress in the seeding stage and no drought stress and the sub-plots included three cultivars I.L.111, L.R.V.51.51, and K.W.2. Seed yield, oil yield, oil percentage are important traits measured. The obtained results show that among the different levels of drought stress, the stress in the stages of budding and the beginning of flowering caused a significant decrease in terms of seed and oil yield. Also, among the studied cultivars, L.R.V.51.51 had the best seed and oil yield. and the lowest sensitivity of safflower to drought stress is in the seed setting stage, because the yield of seeds and oil in this stage of stress did not have any significant difference compared to non-stressed conditions.

Drought is one of the most important factors limiting corn production in the world. On the other hand, the use of renewable resources and inputs such as vermicompost is one of the principles of sustainable agriculture. Therefore, in order to investigate the effect of deficit irrigation, chemical fertilizers and vermicompost an experiment has been performed in the form of split split plots in a randomized complete block design with 3 replications for two years (2017 and 2018) in Kermanshah Agricultural Research and Training Center. Irrigation treatment include optimum, 80% and 60% of water requirement. Chemical fertilizer include 100% and 50% recommended and vermicompost include 0, 2, 4,and 6 ton ha-1 arranged as main plots, sub plots, and sub sub plots, respectively. Results show that leaf area index is decreased from 4.51 to 1.6 from normal irrigation to intense drought stress. The highest yield of fresh forage (82.5 ton ha-1) is obtained in optimal irrigation treatment and combined use of 100% chemical fertilizer and 6 ton ha-1 of vermicompost and the lowest rate (30.1 ton ha-1) is related to 60% water requirement and no use of vermicompost chemical fertilizers. At all irrigation tratments, the percentages of forage protein increase with the use of fertilizers and vermicompost, and the highest percentage of forage protein (10.2%) is obtained in complete irrigation treatment and 100% fertilizer application and 6 ton ha-1 vermicompost. Based on the results in irrigation treatment by 60% of water requirement and application of 50% of chemical fertilizer, application of vermicompost at the rate of six tons per hectare, compared to no application, increases fresh forage by 26.26% and protein by 6.9%.

In order to survey the resistance of wild oat populations to clodinafop propargyl herbicide, an experimental study was conducted at the Department of Weed Science, Plant Pest and Disease Research Institute greenhouse in 2008. Treatments included 12 wild oat populations suspected of being resistant to clodinafop propargyl and a susceptible biotype collected from Fars Province. A dose-response study was conducted for 13 wild oat populations. In this study, wild oat populations were sprayed during the 2–4 leaves stage using eight doses of clodinafop propargyl including 0 to 16 times the recommended dose (64 g ai ha-1). Biomass and surviving plant measurements were performed four weeks after herbicide application. Results of this study indicated that all suspected populations were resistant to clodinafop propargyl herbicide. The comparison of resistance index on the basis of biomass and surviving plants showed that the W/F-M2/85 population from Marvdasht had the highest level of resistance. This population could preserve over 50% more of both biomass and surviving plant relative to the control at 16 times (1024 g ai ha-1) the recommended dose.