Agrotechniques in Industrial Crops
Volume:3 Issue: 3, Summer 2023

Cold and Freezing stresses cause harmful and devastating damage to many agricultural and horticultural crops. In early December of this year (2016), the occurrence of frost stress led to damage to citrus orchards in the north of the country, especially in the east of Mazandaran province. Investigating and calculating the damage to the orchards after the occurrence of cold and/or frost stress is one of the first actions of the Ministry of Jihad Agricultural and its subordinate organizations. However, the exact estimation of the orchards is one of the problems in this area. that considering the harvest season of the main citrus crops of the province hadn't yet started (Thomson orange) and the fruits were still on the tree (half ripe), the amount of frost damage increased. Due to the sustainability of the tangerines, especially Unshiu, the amount of damage to the fruits was little or few. In addition, the result of evaluating frost damage to citrus trees showed that the amount of leaves and fruit damage in the young trees was much more than in the older trees. The amount of fracture of trunks and main branches caused by snowfall was much higher in the hillsides and foothills compared to the plains. According to the calculated observations, it was found that the amount of damage to Thompson oranges in the cities of Babol, Ghaemshahr and Sari was higher than in the other regions due to a decrease in the air temperature to -4 degrees C and a longer glacial period. The fracture of the trunk and main branches of the citrus tree in the cities of Ghaemshahr and Babol was more than in the other regions. Also, the dryness of Thomson orange leaves in the cities of Babol, Ghaemshahr and Sari was more than in the other regions. The leaves and fruits of Page tangerines were damaged to different degrees, but Unshiu tangerines weren't severely damaged in this event.

DNA barcoding is a straightforward strategy that uses short orthologous genetic sequences and standard genomes to specify species. This technique has the capability of molecular identification, detection of living species and discovery of unfamiliar species, preservation of genetic resources, identification of genetic diversity and phylogenetic characterization, and testing of differentiated existing plant species, as well as assuring the safety and efficacy of pharmaceuticals. In this experiment, the allelic diversity of 7 classes of medicinal plants viz. fenugreek, local fenugreek, waybread, cumin, flax, fixweed and sesame, from Ilam and Khuzestan provinces; west and south of Iran, respectively, was carried out employing this technique and with the aid of primers designed and established on ITS nuclear barcodes (ITS1 and ITS2 genes). The results indicated that there was a great difference between the fragments and the duplicated sequences of ITS1 and ITS2 barcodes in different samples. Moreover, the nucleotide searching of the sequences showed that there was a very high similarity (more than 90%) between the acquired sequences and their equivalents in the NCBI database. The nucleotide sequence of the ITS1 gene of fenugreek showed the highest similarity (78.2%) with native fenugreek. Regarding the ITS1 gene, more amount of G~C content than A~T was observed and, in the waybread plants the amount of C base was higher than G, and for native fenugreek, the amount of A~T content was more than G~C. In the case of ITS2 position, in all examined samples (except the fixweed plant, which had higher A~T), the values ​​of G~C content were higher than A~T. The output of the cluster analysis with the UPGMA algorithm showed the precise grouping and separation of species and the high potential of these sequences using the barcode system in the phylogenetic evaluation of medicinal plant species.

Crop production in dry areas is strongly affected by water shortage. In these regions, the application of water-absorbent materials is a useful strategy for sustainable crop production. Therefore, the aim of this study was to investigate the effect of two water preservative materials (WPM) on the growth and yield of sesame under two irrigation regimes. The experiment was carried out as factorial based on a randomized complete block design with three replications, during 2018 and 2019. Experimental factors were water availability levels (100 and 50% of sesame water requirement as normal and deficit irrigation, respectively) and application of WPM, including control (no-WPM), 125 kg ha-1</sup> super absorbent polymer (SAP), 6200 kg ha-1</sup> Zeolite (Z1), 11200 kg ha-1</sup> Zeolite (Z2), SAP+Z1 and SAP+Z2. At the end of both growing seasons, vegetative growth parameters, yield components, seed and biological yields, water use efficiency and seed quality indices (oil and protein contents) were measured. The highest and the lowest amounts of vegetative parameters were obtained at SAP+Z2 under normal irrigation and control under deficit irrigation, respectively. Yield component indices were improved significantly by all WPM especially SAP+Z2 at both levels of irrigation. The highest seed yield was recorded by SAP+Z2 under normal irrigation (1304 and 1481 kg ha-1</sup>, for the first and the second growing seasons, respectively). The highest oil yield (749 and 843 kg ha-1</sup>, for the first and the second growing seasons, respectively) was gained at SAP+Z2 under normal irrigation, while its lowest value (125 and 136 kg ha-1</sup>, for the first and the second growing seasons, respectively) was obtained with no- WPM under deficit irrigation. Similar trend was observed for protein yield. Overall, despite yield reduction, deficit irrigation improved water use efficiency. Moreover, WPMs were useful to improve growth and yield of sesame under both irrigation regimes.

Dust from cement factories and sand crushers can cause stress by depositing on the leaves. Accordingly, in areas that are often exposed to such problems, it is important to investigate its effect on plant growth and physiology. This experiment was simulated to investigate dust deposition on soybean leaves and their physiological characteristics. The experiment was carried out on soybean [Glycine max</em> (L.) Merr. Var. Hobbit] via factorial in the form of randomized complete block design (RCBD) with three replications in 2016 and 2017. The factors included the type of dust (cement, clay, and sand), each of them 20 g m-2</sup> at different stages of soybean growth (V3 (third-node), R1 (beginning bloom), R3 (beginning pod) and R5 (beginning seed)). Plant traits measurements included chlorophyll content, stomatal conductance, catalase activity, soluble sugar, chlorophyll fluorescence (Fv</sub>/Fm</sub>), and seed yield. The results proved that dust deposition had significant effects on reducing stomatal conductance, photosynthetic pigments, Fv</sub>/Fm</sub>, and soybean yield. Finally, the use of cement dust from stage V3 led to a significant reduction in some traits. In this treatment, the amount of damage was higher with the increase of dust deposition period.

Tobacco (Nicotiana</em> tabacum</em> L.) </strong>is a significant cash crop in Iran. It serves as a source of income for smallholder farmers and commercial fields. In order to investigate the growth indices and yield of two Virginia tobacco cultivars an experiment was conducted in a split factorial based on RCBD design with eight treatments and three replicates during the 2020 cropping seasons. The treatments consisted of two application methods of N and K fertilizer (soil and foliar application), planting arrangement </strong>(double- and single-row) in the main plot and two Virginia tobacco cultivars (TC100 and NC100) in the sub-plot. Results showed that the highest value of tobacco leaf area index (LAI), crop growth rate (CGR), relative growth rate (RGR), </strong>and total dry matter (TDM) were recorded where TC100 cultivar planted in double-row spacing and sprayed with N and K nutrients. Conversely, the lowest values of LAI, CGR, RGR and TDM were recorded where the NTC100 cultivar was planted in single-row spacing and received soil application of N and K. The overall results indicated that </strong>double-row and foliar application of N and K fertilizers could improve tobacco growth indices and ultimately its yield.

Optimum germination and seedling establishment are important stages in the life cycle of plants with dormant seeds. This research was conducted to evaluate the impact of seed priming on the germination indices and seedling growth of cumin seeds with different lifetimes. Cumin seeds of different lifetimes (freshly harvested seeds, 12 and 24 months old) were soaked in distilled water (hydropriming), KH2</sub>PO4 </sub>(1 and 2%), NaH2</sub>PO4</sub> (1 and 2%), ascorbic acid (AA; 100 and 200 mg L-1</sup>) and Gibberellic acid (GA; 100 and 200 mg.L-1</sup>) at 4 °C and 20 °C for 12 or 24 h. Seed priming treatments caused significant improvement in the germination of seeds with all three lifetimes. In 12 and 24 months old seeds, seed priming with NaH2</sub>PO4 </sub>and AA were more effective in improving the germination indices compared to other priming composition. However, in freshly harvested seeds, due to relative dormancy, treatment with GA was more effective compared to the other priming treatments. In the most of germination indices, seed priming at 20 °C along with 24 h showed higher effectiveness compared to other priming temperature and duration combinations. The overall results showed that the response of cumin seeds to different priming treatments depends on seed age.