Biomass Fresh Weight Research Articles

Ammonium to total nitrogen ratio affects the purslane (Portulaca oleracea L.) growth, nutritional, and antioxidant status

Purslane (Portulaca oleracea L.) is a widespread weed, which is greatly appreciated for its high nutritional value. The present work evaluated the effect of different ammonium/total nitrogen ratios (NH4/Total N: Nr 0.01–0.15) on growth, physiological and biochemical parameters, and nutrient accumulation in different plant parts of hydroponically grown purslane, under two growing seasons, spring and autumn. Young seedlings of purslane were transferred to a Nutrient Film Technique (NFT) system and they were exposed to different Nr levels. The pH and the electrical conductivity of the nutrient solution were kept constant at 5.8 and 2.3 mS cm−1, respectively. After the end of the cultivation periods (19 days for spring and 22 days for autumn), a series of assessments (growth parameters, mineral content in different plant organs, antioxidant status of the plant, etc.) were done. Plant height, leaf number, root fresh weight and plant biomass revealed decreased trends at the higher NH4/total N ratios, especially during the autumn growing season. Total phenols, flavonoids and antioxidant capacity appeared increased at Nr ≤ 0.10 during both seasons (autumn and spring), revealing higher nitrogen accumulation rates and increased water and nutrient use efficiency. Purslane plants grown in Nr 0.05–0.10 revealed a less intense oxidative stress, with decreased lipid peroxidation levels that was the result of the activation of both enzymatic (superoxide dismutase, catalase and peroxidase) and non-enzymatic (ascorbic acid) antioxidant capacity of the plant. Increased Nr resulted in the accumulation of potassium, while calcium and magnesium levels in leaves were decreased. Additionally, the greater water use efficiency was measured for plants grown under Nr 0.01–0.05. Therefore, the recommended ammonium/total nitrogen ratio for purslane production of increased yield, improved nutritional value and efficient use of water and nitrogen sources is to employ Nr of 0.05, while additional care should be addressed during autumn periods as plants are subjected to greater impacts of the Nr ratio.

The Endophytic Entomopathogenic Fungus Beauveria bassiana Alleviates Adverse Effects of Salt Stress in Potato Plants

The considerable decrease in crop productivity associated with the expansion of saline soils is an acute problem in agriculture. Endophytic fungi positively affect plant fitness under salinity conditions. The effects of potato inoculation with the conidia of the Beauveria bassiana strain Sar-31 on growth (the weight of fresh and dry biomass, shoot and root length, numbers of stolons and leaves, and the leaf surface) and physiological indices (the concentration of pigments, free proline and malondialdehyde, and antioxidant enzymes’ activity) were evaluated under moderate chloride salinity (100 mM). The results indicated that the plant’s association with the fungus mitigated the negative impact of salinity probably because of the activation of antioxidant enzymes and accumulation of free proline in potato tissues. Moreover, under the influence of B. bassiana Sar-31, the number of stolons significantly increased, which is one of the main characteristics of potato as an agricultural crop. Thus, Sar-31 may be a promising candidate for further investigation of its ability to stimulate growth and increase the stress tolerance of potato plants.

Effect of sucrose in strawberry micro-propagation using platform bioreactor under temporary immersion system

The study was carried out in the tissue culture laboratories at the College of Agriculture / University of Kufa during the period from April 2020 to October 2021 where the aim was to assess the efficiency of micropropagation of strawberries by adding different concentrations of sucrose (30, 40 and 50 g.L-1 ) to the nutrient medium in combination with different cultivation systems: Semi-solid media system and temporary immersion system using the Plantform bioreactor. The results showed that both the highest concentration of sucrose and the culture system under the medium immersion, individually or combined, were the highest and significantly effective in increasing the rate of number of shoots (runners), leaf content of macro and minor elements, total soluble sugars, plant pigments and fresh weight of biomass. Generally, the highest values were recorded in the shoots grown in liquid media supplied with 50 g.L-1 sucrose under temporary immersion in the PlantForm bioreactor compared with those grown in semi-solid media. Keywords: Fragaria × ananassa, micro-propagation, plant nutrition, tissue culture, PlantForm bioreactor

Effect of nutrient solution concentrations on the growth and yield of potato (Solanum tuberosum L.) varieties grown from apical rooted cutting in a hydroponic system

This study evaluated the effects of nutrient stock solution concentrations on the growth and yield of potato varieties grown from apical rooted cuttings (ARCs). A greenhouse experiment was conducted at the Climate and Water Smart Agriculture Center at Egerton University, Kenya. The experiment was laid out in a split-plot arrangement in randomized complete block design, where the main plot comprised three nutrient concentrations, i.e., 75% (N75), 100% (N100) and 125% (N125) of the ADC-Molo’ nutrient formulation. The subplots were allocated to four potato varieties (Shangi, Wanjiku, Nyota and Unica). The results showed that there were no significant (p<0.05) interaction effects of the nutrient stock solution concentrations application rates on the growth attributes of ARCs. The main effects of N125 gave the tallest plants (32.29cm) at 60 days after planting (DAP), highest normalised difference vegetation index (NDVI) (0.60) at 75 DAP, plant survival rate (82.15%) at 75 DAP, and fresh weight (79.04g) and dry matter (31.26%) of aboveground biomass (AGB). Nyota variety produced taller plants (26.90cm) at 60 DAP, gave higher NDVI values (0.53) at 75 DAP, and higher fresh weight (64.87g) and dry matter (27.60%) of the AGB. Significant (p<0.05) interactions were observed in the yield parameters. The interaction between N125 and Nyota (11.33) and Wanjiku (10.67) gave the highest number of minitubers, the highest yields were obtained between the interaction of N125 and Unica (16.38t/ha). Therefore, to achieve high growth and yields of ARCs under hydroponic system, seed potato producers should use 125% of the ADC Molo nutrient formulation.

Screening For Salt Tolerance of 12 Turkish Triticale Cultivars during Germination and Early Seedling Stage

This investigation was carried out to determine the response of 12 Turkish cultivars to different salt stress levels during the germination and early seedling stages at Hatay Mustafa Kemal University in 2022. In present research, four different sodium chloride treatments (60, 120, 180 and 240 mM) and a control (0 mM) treatment were used. Germination ratio, germination index, mean germination time, root and shoot length, root and shoot fresh weight, root and shoot dry weight and biomass weight parameters were investigated to determine the salt tolerance of triticale cultivars. Cultivars, salt doses and their interactions had significant effects on all examined characteristics. In general, germination parameters and early seedling stage characteristics of the cultivars were adversely affected by increasing salt doses. Yet, it was determined that the responses to increasing salt doses were different among the cultivars. Although Mehmetbey cultivar was undesirably affected by increased salt doses, it was found to be more resistant than the other cultivars. On the other hand, Umranhanim was determined as the most sensitive cultivar to salt stress. After investigating the resistance of Mehmetbey cultivar to salt stress under field conditions, this cultivar can be included into breeding programs or cultivated in fields with salinity problems.

Aqueous extraction of red seaweed bioactive compounds and synthesis of silver nanoparticles for agriculture applications

In this study, an aqueous extract of Gracilaria crassa and Grateloupia lithophila was used for the green synthesis of silver nanoparticles (AgNPs) to control plant disease and support plant growth. The synthesised AgNPs were characterised using a UV–visible spectrophotometer, FTIR, XRD, SEM, EDAX, TEM and DLS analysis. The TEM image revealed that synthesised nanoparticles with average size of 51 nm and 20 nm were observed in G. crassa and Grateloupia lithophila extract, respectively. The green synthesised AgNPs exhibited a strong antibacterial activity against Xanthomonas axonopodis pv. citri and Xanthomonas oryzae pv. oryzae, and investigated the effect of biogenic AgNPs on seed germination and seedling growth of rice plants (Oryzae sativa L). Both the sizes (51 and 20 nm) of AgNPs treatments (50 μg/ml conc.) resulted in the highest seed germination rate (98 and 99%), longer roots (17.51 ± 0.50 and 17.68 ± 0.10 cm) and shoot lengths (5.68 ± 0.12 and 6.18 ± 0.10 cm), and produced higher amount of fresh (8.98 ± 0.34 and 9.00 ± 0.14 mg) and dry (3.68 ± 0.05 and 3.80 ± 0.12 mg) biomass weights. On the other hand, rice seedlings treated with both sizes of AgNPs, particularly at 100 μg/ml concentration, responded with a lower rate of seed germination, shorter root and shoot length and a lower amount of fresh and dry biomass weight was observed. The nanocomposites synthesised from Grateloupia lithophila (20 nm) were more effective in seed germination and seedling growth than G. crassa (51 nm) nanocomposites. In this study, one-step synthesised AgNPs from red seaweeds extracts controlled the bacterial pathogens causing disease in rice and promoted the growth of the plant.

The Effect of Irradiation Methods on Biomass Yield on Mix of Corn (zea mays) and Mung Bean (Vigna radiata) with Hydroponic system

The objectives of this research was to find effect of irradiation methods on the production of biomass fresh weight, leaf and root dry weight on combination of mung bean and corn with hydroponic system. This research was design with experimental method using Completely Randomized Design with 2 treatmens and 9 replications. The observed of P1 = irradiation method with the sunlight for 12 hours and P2 = irradiation method with LED grow light 7. watt for 16 hours. Parameters observed were biomass fresh weight, leaf and root dry weight Data were analyzed using of two samples Independent T-tes. The result showed that biomass fresh weight and leaf dry weight of irradiation with LED higher than irradiation with the sunlight, the average’s 3155,844 g/m2, and 55,14 g/m2, but no significant effect on dry weight of root.

Effects of silver nanoparticles on seed germination and growth performance of pea (Pisum sativum)

Agricultural biotechnology has become familiar with nanomaterials' properties and potential use. The present experiment was conducted to examine the effect of 8.1 ± 1.6 nm sized silver nanoparticles (AgNPs) on the growth performance and yield quality of pea (Pisum sativum) as well as Arbuscular Mycorrhizal Fungi (AMF) and Rhizobium population in the soil. Pea seeds were separately treated in 3 h with 1 mM, 2.5 mM, and 5 mM of AgNPs aqueous solution, and after 2 weeks their effect on seed germination, leaf number, shoot, and root length, shoot and root dry weight, fresh biomass, and dry biomass weight were investigated in laboratory condition using Murashige and Skoog (MS) Basal Medium. Results showed that 2.5 mM AgNPs had a significant positive impact and notably increased all the experimental growth parameters mentioned above of pea compared with the control. The experiment was also conducted in an open environment under a natural condition where 2.5 mM AgNPs improved 31.57 % weight of fruit and 9.09 % of seed weight without causing any harm to the symbiotic microbes (AMF and Rhizobium bacteria). Whereas, the other concentrations of nanoparticles (1.0 mM and 5.0 mM) showed varied impacts on the germination, growth, and yield of pea in comparison with the control. For the first time, the outcome demonstrated the successful use of 2.5 mM AgNPs in enhancing the growth and yield of peas, and increased AMF colonization but showed no impact on Rhizobium compared to the control.

Assessment of Morphological Variations and Crop Performance among Commonly Cultivated Bambara Groundnut (Vigna subterranea (L) Verdc.) Landraces in Gombe, Nigeria

Bambara groundnut is cultivated by low-income earning farmers at the subsistence level without knowledge of genetic diversity on major morphological and yield traits. This study aimed to assess morphological variations and crop performance among commonly cultivated Bambara groundnut landraces. The five most commonly cultivated Bambara groundnut landraces were collected from farmers and were planted randomly in a complete block design (RCBD) with three replications in the Botanical Garden of Gombe State University. The results of the analysis of variance from this study revealed significant variation among some of the traits. The results on germination percentage showed that the landraces germinated between seven to ten (7-10) days after planting with 73% and 100% as the lowest and highest mean percentages. The highest mean number of leaves observed was in Stripped Black 122 whereas the lowest mean was 52. The highest mean observed at ten weeks after planting was 31.20 and the lowest mean was 23.00 in stripped brown and stripped black landraces. The highest mean plant canopy spread observed was 70cm in the white landrace, whereas the lowest mean plant canopy observed was 35cm in the black landrace. The highest mean biomass fresh weight observed was 214.95 among the white landrace while the lowest mean observed was 80.30 among the red landrace. A similar trend was recorded on biomass dry weight where the white landrace recorded 101.23 while the red landrace recorded the lowest mean biomass dry weight at 30.62 these traits have highlighted the significance chosen various parameters in selection for breeding and improvement of Bambara groundnut.

Shallot growth and yield supported by irrigation and nitrogen application in utilizing dry land area in Mesuji, Lampung Province, Indonesia

Lampung Province, Indonesia local government intended to extend shallot cultivation in Mesuji Regency, Lampung (-3.86, 105.43). Mesuji has 21,863.5 ha dry land area, with unproductive land of 10,325.6 ha which could be potential for growing <em>shallot</em>. However, horticulture crops such as shallot often face obstacles in dry land since dry land characterized with poor soil nutrient and limited water. The objective of this research are to analyze the effects of nitrogen fertilizer and different irrigation volumes on shallot growth and production, investigate shallot suitability to Mesuji agro-climate, and estimate shallot yield potential in Mesuji. The treatments on factorial split block were: without N, 80 kg N ha<sup>-1</sup> , 160 kg N ha<sup>-1</sup>, and 240 kg N ha<sup>-1</sup> and the irrigation levels: 25, 50, 75 and 100% of ETc; ETc is crops evapotranspiration. The Mesuji agro-climate was evaluated using standardized precipitation index (SPI) and the yield was simulated by Aquacrop model. The results showed that the effort of shallots production with a high fresh weight of bulbs and biomass in the Mesuji area requested water at least 75% ETc and N fertilizer doses of 160 kg N ha<sup>-1</sup>. The SPI indicated near normal condition was more than 65%, and drought existed in a small percentage in both places (a total of 16.9% for Brebes the centre of shallot production and 19.43% for Mesuji). The AquaCrop simulation gave a good yield estimation (simulated 19.451 ton ha<sup>-1</sup> and observed 17.351 ton ha<sup>-1</sup>). There is a possibility that shallot will grow well in the Mesuji area even though the quality of the shallot should be further tested.

Domesticating aquatic plants in hydroponic systems to demonstrate and advance phytoremediation of the artificial sweetener acesulfame

Artificial sweeteners (ASs) are ubiquitously detected in the global water system, among which acesulfame (ACE) is an emerging contaminant for its chemical and biological stability and unsatisfying removal by conventional or advanced treatment technologies. Phytoremediation is an effective and sustainable in-situ remediation technology that this study is the first to explore ACE removal by aquatic plants. The emergent plants, Scirpus Validus (S. validus), Phyllostachys heteroclada Oliver (P. heteroclada) and Acorus tatarinowii (A. tatarinowii) showed superior removal capability than eleven floating plants, and demonstrated high phytoremediation efficiencies (PEs) of up to 75 % after 28 d domestication. ACE removal by the three emergent plants increased during domestication, as the PEs after 28 d domestication were 5.6–6.5 times of 7 d domestication. Notably, the half-life of ACE was decreased from 20.0 to 33.1 d to 1.1–3.4 d in the plant-hydroponic system, compared with 481.0–1152.4 d in control water without plants. Moreover, A. tatarinowii demonstrated the highest removal capacity for ACE with 0.37 mg/g fresh biomass weight (FW), higher than S. validus (0.27 mg/g FW) and P. heteroclada (0.20 mg/g FW). It is worth noting that a mass balance analysis demonstrated that plant transpiration and plant uptake account for about 6.72 %–18.54 % and 9.69 %–21.67 % ACE removal, while hydrolysis only accounted for about 4 % and photolysis was negligible. The rest ACE may be used as a carbon source by endophytic bacteria and root microorganisms of plants. In addition, increased temperature, pH, and illumination intensity had a significant effect on phytoremediation. In the selected experimental range, the increase of temperature from 15 °C to 35 °C, illumination intensity from 1500 lx to 6000 lx, and pH from 5 to 9 generally accelerated the PEs of ACE during the domestication process. Though the mechanism still requires further investigation, the results provide scientific and feasible data for removal of ACE from water by diverse plants for the first time, and also revealed insights for in-situ treatment of ACE.

Influence of Borassus flabellifer Endocarps Hydrolysate on Fungal Biomass and Fatty Acids Production by the Marine Fungus Aspergillus sp.

Polyunsaturated Fatty Acids (PUFAs) are important nutrients for human health. We aimed to evaluate the efficiency of marine water fungus Aspergillus sp. (Accession no: MZ505709) for lipid biosynthesis. The Yeast Extract Glucose (YEG) medium was supplemented with different concentration of Borassus flabellifer Endocarps Hydrolysate (BFEH; 1-5%) to evaluate the fungal biomass and its lipid accumulation. The combination of glucose and BFEH as carbon source increased the fresh weight (25.43 ± 0.33g/L), dry weight (21.39 ± 0.77g/L) and lipid yield (3.14 ± 0.09g/L) of fungal biomass. The lipid content of dried fungal biomass has shown 91.08 ± 5.07mg cod liver oil equivalents/g and 125.98 ± 5.96mg groundnut oil equivalents/g biomass. GC-MS and NMR spectrometry analysis revealed the compounds involved in fatty acid metabolism and lipid signaling pathways along with the presence of linolenic acid. Interestingly, fungus grown in BFEH enriched medium has recorded the maximum amount of lipids with major fatty acid derivatives. Increase in the growth rate of Artemia franciscana was observed, when the extracted fungal lipid was supplemented as a food supplement. Therefore, this study suggests that marine fungal lipid may serve as potential natural compound as nutraceuticals and aquafeeds.

Construction of a high-density genetic linkage map and QTL mapping for bioenergy-related traits in sweet sorghum [Sorghum bicolor (L.) Moench

Sorghum is an important but arguably undervalued cereal crop, grown in large areas in Asia and Africa due to its natural resilience to drought and heat. There is growing demand for sweet sorghum as a source of bioethanol as well as food and feed. The improvement of bioenergy-related traits directly affects bioethanol production from sweet sorghum; therefore, understanding the genetic basis of these traits would enable new cultivars to be developed for bioenergy production. In order to reveal the genetic architecture behind bioenergy-related traits, we generated an F2 population from a cross between sweet sorghum cv. 'Erdurmus' and grain sorghum cv. 'Ogretmenoglu'. This was used to construct a genetic map from SNPs discovered by double-digest restriction-site associated DNA sequencing (ddRAD-seq). F3 lines derived from each F2 individual were phenotyped for bioenergy-related traits in two different locations and their genotypes were analyzed with the SNPs to identify QTL regions. On chromosomes 1, 7, and 9, three major plant height (PH) QTLs (qPH1.1, qPH7.1, and qPH9.1) were identified, with phenotypic variation explained (PVE) ranging from 10.8 to 34.8%. One major QTL (qPJ6.1) on chromosome 6 was associated with the plant juice trait (PJ) and explained 35.2% of its phenotypic variation. For fresh biomass weight (FBW), four major QTLs (qFBW1.1, qFBW6.1, qFBW7.1, and qFBW9.1) were determined on chromosomes 1, 6, 7, and 9, which explained 12.3, 14.5, 10.6, and 11.9% of the phenotypic variation, respectively. Moreover, two minor QTLs (qBX3.1 and qBX7.1) of Brix (BX) were mapped on chromosomes 3 and 7, explaining 8.6 and 9.7% of the phenotypic variation, respectively. The QTLs in two clusters (qPH7.1/qBX7.1 and qPH7.1/qFBW7.1) overlapped for PH, FBW and BX. The QTL, qFBW6.1, has not been previously reported. In addition, eight SNPs were converted into cleaved amplified polymorphic sequences (CAPS) markers, which can be easily detected by agarose gel electrophoresis. These QTLs and molecular markers can be used for pyramiding and marker-assisted selection studies in sorghum, to develop advanced lines that include desirable bioenergy-related traits.

KAJIAN PARAMETER GENETIK KARAKTER KUANTITATIF TANAMAN JAGUNG (Zea mays L.) DI LAHAN KERING

The narrow-sense heritability and expected selection response are very important to be recognized in the F2 population of maize to determine the character to be selected. This study aimed to estimate the narrow-senseheritability and the expected selection response of quantitative characters in the F2 population. The experimental method used in this study was field experiments on dry land using pumping wells for irrigation. This was conducted from April to October 2022 in Amor-Amor Hamlet, Gumantar village, North Lombok district. The experiment was carried out in two growing seasons; namely: the first growing season was to establish kinship with NC1 and the second season was to test the results of crosses by used a Randomized Block Design (RBD). The number of treatments was 105; derived from 35 male parents. Each treatment was replicated 2 times, so there were 210 experimental units. Data were analyzed using analysis of variance (ANOVA); and then calculation of narrow sense heritability and response selection expectations was conducted. The results showed that the narrow sense heritability of all the quantitative characters observed was low, while the selection response of the biomass weight per plant was high; Plant height, leaf angle, and dry cob weight per plant were moderate and other characters were low. Fresh biomass weight per plant can be used as a selection criterion for improving the stay-green character. Yield can be improved through enhancing dry cob weight per plant.
 
 Keywords: corn; heritability; response of expected selection and dry land.

Characterization of the physico-chemical properties of the natural habitat and in vitro culture effects on the biochemistry, proliferation and morphology of Lemna minuta

In this study, the ecological conditions of the natural habitat of Lemna minuta Kunth in Morocco were investigated, and the impact of five synthetic growth media (Murashige-Skoog (MS), Schenk-Hildebrand (SH), Hoagland medium (HM), 10X Algal Assay Procedure (AAP), and Swedish Standard Institute medium (SIS)) on the morphophysiological and biochemical parameters was analysed. The morphophysiological parameters included root length, frond surface area, and fresh weight, while the biochemical parameters included photosynthetic pigments, carbohydrates, and protein content. The study was conducted in vitro in two phases: an uncontrolled aeration system (Phase I) and a controlled aeration system (Phase II).The results showed that the pH, conductivity, salinity, and ammonium levels in the natural habitat were within the optimal range for duckweed growth. The measured orthophosphate concentrations were higher compared to previous observations, while the recorded chemical oxygen demand values were low. The study also revealed a significant effect of the culture medium composition on the morphophysiological and biochemical parameters of the duckweed. The fresh weight biomass, relative growth rate in fronds, relative growth rate in surface area, root length, protein content, carbohydrates, chlorophyll (a), chlorophyll (b), total chlorophyll, carotenoids, and the chlorophyll (a/b) ratio were all affected by the culture medium.The most accurate regression models described the growth index GI(F) based on time and in vitro culture conditions in both phases. In Phase I, the best models for MS, SIS, AAP, and SH media were linear, weighted quadratic, cubic, and weighted cubic, respectively. In Phase II, the best models for all growth media were linear. The time coefficients (in days) for Phase II were 0.321, 0.547, 1.232, 1.470, and 0.306 for AAP, HM, MS, SH, and SIS, respectively.Comparing the morphophysiological and biochemical parameters of fronds from different media and analysing the regression model results showed that the SH and MS media were the best among the tested media for the in vitro culture of L. minuta in controlled aeration conditions. However, further research is needed to develop new synthetic media that best promote the growth and maintenance of this duckweed in long-term culture.

Growth and Yield of Aloe Vera (L.) Burm.f. As Influenced By Organic Manures and Chemical Fertilizers

Influence of organic manures (10 ton ha-1), nitrogen (50 and 100 kg ha-1), phosphorus (10 and 20 kg ha-1) and potassium (30 and 60 kg ha-1) on the growth and yield of Aloe vera (L.) Burm.f. (Aloe barbadensis Mill.) were evaluated. Experiment was conducted in a randomized design replicated thrice with eleven treatments with NPK and without NPK fertilizers. Highest length of leaf (18 cm), highest leaf area (23.40 cm2plant-1), highest leaf area index 0.06 were observed in ACI10ton ha-1plus N50P10K3O kg ha-1 treatment, highest fresh weight (78.23gplant-1) and highest dry weight (9.58 gplant-1) of plant biomass were observed in GTS 10ton ha-1 treatment. Highest concentration of N (2.69%) and protein content (16.84 %) in the leaf were recorded in GTS10 ton ha-1 treatment. Results revealed that the best growth performance and yield, and protein content in the leaf of Aloe vera was observed in GTS10 ton ha-1 treatment. Dhaka Univ. J. Biol. Sci. 31(2): 203-212, 2022 (July)

Evapotranspiration Rates of Three Sweet Corn Cultivars under Different Irrigation Levels

Understanding plants’ response to different irrigation levels is essential for developing effective irrigation scheduling practices that conserve water without affecting plant growth and yield. The objective of this study was to evaluate the responses of three sweet corn (Zea mays var. saccharata) cultivars 1170, 8021, and Battalion under three irrigation levels (50%, 75%, and 100%). Irrigation treatments were based on soil moisture management allowable depletion. Replicated trials were conducted, in an open field using 1-gal containers, at the Tropical Research and Education Center, Homestead, FL. A drip system with microsprinklers was used for irrigation. Daily crop evapotranspiration (ETc) rates were measured using a digital scale based on differences in weights of soil containers and plants. Reference evapotranspiration (ETo) was calculated using the FAO-Penman-Monteith equation. Crop-coefficient (Kc) values for the three cultivars were calculated from measured ETc and calculated ETo. In addition, leaf area, stomatal conductance, and fresh biomass were measured. Total irrigation amounts corresponding to the 50%, 75%, and 100% treatments were 116, 162, and 216 mm, and total ETc values were 128, 157, and 170 mm, respectively. The two deficit irrigation treatments (50% and 75%) resulted in a reduction of ETc for the three cultivars compared with the 100% irrigation treatments. Results also showed that under 75% and 100% treatments, Kc values were usually greater than 1 for the three cultivars and reached as high as 1.5. Additionally, leaf area and fresh biomass weight in the 50% treatment were mostly lower than in the 75% or 100% treatments.

Screening Spring Wheat Genotypes for TaDreb-B1 and Fehw3 Genes under Severe Drought Stress at the Germination Stage Using KASP Technology.

Drought stress is a major yield-limiting factor throughout the world in wheat (Triticum aestivum L.), causing losses of up to 80% of the total yield. The identification of factors affecting drought stress tolerance in the seedling stage is especially important to increase adaptation and accelerate the grain yield potential. In the current study, 41 spring wheat genotypes were tested for their tolerance to drought at the germination stage under two different polyethylene glycol concentrations (PEG) of 25% and 30%. For this purpose, twenty seedlings from each genotype were evaluated in triplicate with a randomized complete block design (RCBD) in a controlled growth chamber. The following nine parameters were recorded: germination pace (GP), germination percentage (G%), number of roots (NR), shoot length (SL), root length (RL), shoot-root length ratio (SRR), fresh biomass weight (FBW), dry biomass weight (DBW), and water content (WC). An analysis of variance (ANOVA) revealed highly significant differences (p < 0.01) among the genotypes, treatments (PEG25%, PEG30%) and genotypes × treatment interaction, for all traits. The broad-sense heritability (H2) estimates were very high in both concentrations. They ranged from 89.4 to 98.9% under PEG25% and from 70.8 to 98.7% under PEG30%. Citr15314 (Afghanistan) was among the best performing genotypes under both concentrations for most of the germination traits. Two KASP markers for TaDreb-B1 and Fehw3 genes were used to screen all genotypes and to study the effect of these on drought tolerance at the germination stage. All genotypes with Fehw3 (only) showed a better performance for most traits under both concentrations compared to other genotypes having TaDreb-B1 or having both genes. To our knowledge, this work is the first report showing the effect of the two genes on germination traits under severe drought stress conditions.

Effects of some control methods on Johnson grass and yield components in tomato fields

Johnson grass is one of the most dangerous and difficult to control weeds. The aim of this study was to determine the effect of different control methods on Johnson grass in tomato fields and to investigate the effect of these methods on the phenological stages and yield indicators of tomatoes. The study was carried out during the 2019 and 2020 seasons. The experiment treatments were as follows: hand hoe, mulch, preemergence herbicide pendimethalin (5 L/ha), postemergence herbicide fluazifop-P-butyl (1 L/ha), and control parcels. The number of flowers, the number of branches, and the length of the plant were determined in tomato. The yield and characteristics of the fruit were calculated and the fruits were analyzed. For Johnson grass, the time for germination, flowering, and seed maturity were determined. Plant height, fresh and dry biomass weight of weed, and rhizomes were also calculated. The results of this experiment showed that the best yield was 64.943 kg/ha in the hand hoe and the fluazifop-P-butyl treatment. The lowest density and fresh biomass of Johnson grass were detected in the fluazifop-P-butyl (217.3 stem/mm$^{2}$, 1009.4 g/m$^{2}$) and the mulch (251.7 stem/mm$^{2}$, 1355.2 g/m$^{2}$) treatments, respectively. The highest density and fresh biomass were detected in control parcels (448.8 stem/m$^{2}$, 3239.2 g/ m2), and in the pendimethalin treatment (334.2 stem/m$^{2}$, 1956.4 g/m$^{2}$), respectively. The percentage of lost yield in the control parcels was 90.1%. Hand hoe was found to be the most effective control method against Johnson grass followed by fluazifop-P-butyl, mulch, and pendimethalin.

Effect of short and long period of salinity stress on physiological responses and biochemical markers of Aloe vera L.

Salinization reduces soil health and quality, drastically limiting growth and reducing land degradation and crop yield. This comprehensive research aimed to evaluate the impact of sodium chloride increment on growth factors, amount of oxidative stress biomarker (Malondialdehyde), osmotic response (evaluated by both proline and sugars contents), photosynthesis efficiency (expressed with chlorophyll fluorescence measurement) and activity of Malate dehydrogenases (MDHs) as a regulator under abiotic stress tolerantly in Aloe in Alzahra University, Tehran. Experiments were conducted in two studies at the following concentration of sodium chloride: 0 (control), 100, 200, and 300 (mM) NaCl for 30 days (short-term treatments) and: 0 (control), 54.7, 109.5, and 164.5 (mM) NaCl for 150 days (long-term treatments). Three replications in completely randomized design were applied. The results showed that while the fresh weight of belowground biomass declined at higher salinity level (164.5 mM), no significant differences were reported in the short period of salt treatments. A considerable amount of free proline was accumulated in both short (3.594 µg.g-1 dw) and long ( 2.20 µg.g-1 dw) term studies which raised the role of proline in osmoregulation. Our results showed the decline of MDA amount (0.0003mmol.g-1FW) in 54.7 NaCl (mM) that may be due to less membrane damage in presence of moderate salinity, indicating a variety of dependent differences in biochemical markers activity.