Values Of Shoot Dry Weight Research Articles

Applicability of the sigmoid model to estimate heavy metal uptake in maize and sorghum as affected by organic acids.

Although assisted phytoremediation using chemical treatments is a suitable technique for the removal of heavy metals (HMs), the estimation of this process using simple models is also crucial. For this purpose, a greenhouse trial was designed to evaluate the effectiveness of citric, oxalic, and tartaric acid on Cd, Pb, Ni, and Zn phytoremediation by maize and sorghum and to estimate this process using sigmoid HMs uptake model. Results showed that mean values of root and shoot dry weight and metals uptake, translocation factor (TF) of Pb and Zn, and uptake efficiency (UE) of Cd in maize were higher than sorghum but the TF of Cd and the phytoextraction efficiency (PEE) and UE of Pb in sorghum were higher than maize. Citric, oxalic, and tartaric acid significantly increased the UE of Pb by 17.7%, 22.5%, and 32.5%, respectively. Tartaric acid significantly increased the mean values of shoot dry weight, shoot Cd, Pb, and Ni uptake, and PEE of Pb and Ni, but decreased TF of Zn. The R2, NRMSE, and KM values indicated the ability of sigmoid HM uptake model in estimating HMs uptake in maize and sorghum treated with organic acids. Thus, tartaric acid was more effective than citric and oxalic acids to enhance phytoremediation potential. Sigmoid HM uptake model is suitable to estimate the HMs uptake in plants treated with organic acids at different growth stages.

Investigating an electro-bio-chemical phytoremediation of multi-metal polluted soil by maize and sunflower using RSM-based optimization methodology

Accumulation of heavy metals (HMs) in soil has become a serious environmental problem due to various anthropogenic activities. Phytoremediation is one of the most cost-effective and environmentally friendly techniques for removing HMs from contaminated soil. However, it is remarked as a slow way of remediation, and it may need some amendments. Thus, in this study, a phytoremediation-based method of zinc (Zn) cadmium (Cd) lead (Pb) and nickel (Ni), comprised of sunflower and maize, was amended by the electro-bio-chemical treatments, comprised of ethylene glycol tetraacetic acid (EGTA), Bacillus subtilis and electrical current. Moreover, the performance of the system was optimized by the response surface methodology (RSM), to optimize the performance of both reactors. A high R2 value of non-linear second-order model showed satisfactory function of RSM in optimizing the performance of the remediation system. The electrical current and EGTA were the main significant factors in increasing growth parameters and translocation factor (TF) of some HMs, respectively. The highest values of shoot dry weight and TF were 15.62 g pot−1 (run 2) and 2.11 (run 4) which belonged to maize and Zn in sunflower, respectively. To achieve the highest possible response, the following optimal values were predicted: electrical current of 2 V cm−1, EGTA concentration of 0.04 mmol kg−1, and Bacillus subtilis level of 1.4 × 109 CFU pot−1 for maximized shoot dry weight efficiencies of 16.14 g pot−1. Also electrical current of 1.97 V cm−1, EGTA concentration of 1.68 mmol kg−1, and Bacillus subtilis level of 0.21 × 109 CFU pot−1 for maximized TF of Zn efficiencies of 1.6. The use of a combination of treatments was more successful than each treatment alone in the removal of HMs by maize and sunflower.

Maize response to nitrogen and phosphorus starter fertilisation in mineral-fertilised or manured systems

Phosphorus (P) is an essential nutrient for maize production, but in temperate areas the P uptake during early growing stages can be limited due to low soil temperature, even though the soil was tested high in P. The objective of this study was to assess the effects of nitrogen and phosphorous (NP) starter fertilisation during early growth stages and its carryover until maize harvest, in mineral-fertilised or manured systems. A field experiment was carried out in north-west Italy during the 2019 and 2020 growing seasons. The trial compared sub-surface placement of NP (diammonium phosphate) or N alone (ammonium nitrate) in bands close to the maize seed furrows, in differing long-term (LT) fertilisation managements: two doses of urea (Min-L and Min-H), two doses of bovine slurry (Slu-L and Slu-H) or two doses of farmyard manure (Fym-L and Fym-H). The two rates, low (L) and high (H), corresponded to 170 and 250 kg N ha−1 year−1 respectively. Compared to N fertilisation, NP starter fertilisation improved early maize growth assessed by leaf area index (LAI) and shoot dry weight (SDW) in all systems. The effects differed between the two years (2019: LAI + 63%, SDW + 67%; 2020: LAI + 36%, SDW + 38%), as 2019 was cool during the first growth. Higher LAI and SDW values were confirmed at crop flowering in the mineral-fertilised systems only. As shoot growth was enhanced by NP starter fertilisation, anthesis occurred 1 day earlier in all systems. However, a response to NP starter fertilisation at harvest was recorded in mineral-fertilised systems only (+1.3 and +3.2 t ha−1 in Min-L and Min-H, respectively). The uptake of P, used as a true indicator of soil nutrient availability, increased with increasing soil Olsen P until 39 mg kg−1. These results suggest that soil test thresholds should be revised for points above which P fertilisation should be suspended.

Multiple Effect of Different Plant Growth Promoting Microorganisms on Beans (Phaseolus vulgaris L.) Crop

Abstract We evaluated the effect of combined Rhizobium tropici, Trichoderma asperellum and plant growth-promoting rhizobacteria (PGPR) in beans crop. The hypothesis that strains of T. asperullum, R. tropici and PGPR combined could improve growth, biomass accumulation and beans yield was tested under greenhouse and field conditions. The treatments consisted of control, mineral nitrogen application and inoculation, isolated and associated with the following microorganisms: Rhizobium tropici, Bacillus subtilis, Trichoderma asperellum and Burkholderia sp. 10N6. Results were evaluated by shoot dry weight (SDW) and root dry weight (RDW), number of nodules and yield components. In greenhouse environment all the microorganisms behaved similarly, and the treatments inoculated with Burkholderia sp. 10N6 (IBu) and R. tropici (IR) stood out regarding the production components. In field conditions the treatments IR and IRTBa presented the highest values of SDW and RDW. Our results suggest that inoculation with R. tropici, T. asperellum and PGPR may promote beans growth and bring benefits to shoot and root accumulation, increase the number of nodules as well as improve yield components, contributing to a sustainable agriculture.

EFFECT OF FOLIAR SPRAYING OF SOME CHELATED MICROELEMENTS ON GROWTH, YIELD AND CHOCOLATE SPOT DISEASE SEVERITY OF FABA BEAN

Field experiment using three faba bean cultivars namely Sakha 1, Sakha 4 and Giza 716 was carried out to study the efficacy of foliar spraying chelated Fe, Mn and Zn individually on vegetative growth, yield and its components, some biochemical constituents and its relation to chocolate spot disease severity caused by Botrytis fabae Sard. during two successive seasons 2017/2018 and 2018/2019 at Etay El-Baroud Agricultural Research Station Farm, El-Beheira Governorate. Sakha 1 cv. had the highest shoot dry weight and leaf area/plant in both seasons. Sakha 4 cv. was the earliest flowering and maturity in the first and second seasons, respectively. Sakha 4 cultivar had the tallest plant and the heaviest 100-seed weight in both seasons, but Giza 716 had the highest number of pods/plant, seed yield /plant and seed yield/fed. in the first season, however Sakha 4 cv. was surpassed the other cultivars in the second season. Chelated Fe, Mn and Zn foliar spray had excellent effects in increasing faba bean growth and yield compared to the fungicide Mancozeb and control treatments. Zn treatment significant increased mean values of shoot dry weight, leaf area/plant, number of branches/plant and seed yield/plant in both seasons. Also, it had the first grade in case of the plant height and seed yield/fed. in the first season, only. Fe treatment significantly increased number of pods/plant and 100-seed weight in the first season, and seed yield/fed. in the second season. Giza 716 cv. had the highest content of chlorophyll a, chlorophyll b and chlorophyll a+b in both seasons. Sakha 4 cv. had the highest percentage of the seed carbohydrates and protein contents. In case of peroxidase and polyphenol oxidase activities, Giza 716 cv. had the first grade. Fe significantly increased chlorophyll a in the first season and chlorophyll b and chlorophyll a + b in both seasons. Zn treatment significantly increased seeds total carbohydrates%, total protein %, leaves peroxidase and polyphenol oxidase activities. Sakha 1 cv. had the least chocolate spot disease severity in the first season and Giza 716 in the second season. The three tested faba bean cultivars sprayed with Mancozeb reduced disease severity in both seasons followed by Fe in the first season and Zn in the second one. Data clear that there were negative association between disease severity and peroxidase and polyphenol oxidase activities in all cases. So it could be concluded that the used micronutrients could resist the detrimental effects of Botrytis fabae on the plant growth and improve yield production.

Phytochemical and morpho-physiological traits of mullein as a new medicinal crop under different planting pattern and soil moisture conditions

Mullein (Verbascum songaricum Schrenk.) is the biggest plant species belonging to the Scrophulariaceae family. The aerial parts of V. songaricum, especially leaves and flowers are used as herbal medicine by indigenous peoples of some regions of Iran. The effects of two planting patterns (square and rectangular) and different irrigation regimes, including irrigation in 90-85 % field capacity (F.C.) or control (I1), irrigation in 60 % F.C. (I2), irrigation in 45 % F.C. (I3), and irrigation in 30 % F.C. (I4) on some phenolic compositions, Malondialdehyde (MDA), catalase enzyme (CAT), proline, and growth parameters of V. songaricum as a new medicinal crop have been investigated. Field experiment was done two consecutive years (2016–17) in semi-arid climate, Southwestern Iran. Total phenolic contents of the ethanol extract from the leaves (2016 and 2017) and flowers (2017) determined by Folin–Ciocalteu assay and phenolic acids and flavonoid compositions of the flowers separated and quantified each component by high-performance liquid chromatography (HPLC). Results indicated that the planting patterns had not significant effects on biochemical and phytochemical features, however, the highest values of shoot dry weight and stem height were obtained from the plants cultivated in the rectangular pattern, and also the maximum dry weight of flowers was achievement from the mullein cultivated in the square pattern. Reduced irrigation significantly increased the contents of MDA, CAT, proline, and secondary metabolites such as total phenolic, phenolic acid (gallic acid), and flavonol quercetin, whereas, photosynthesis pigments and growth parameters (chlorophyll a, chlorophyll b, total chlorophyll contents, canopy diameter, plant height, and dry herbal weight) significantly decreased under deficit irrigation. In conclusion, reduced irrigation under the rectangular pattern significantly increased the amounts of total phenolic and flavonoids in the extracts from the leaves and flowers. Finally, the results of this study can be used in agricultural systems in order to growth, development and increase the quantity and quality yields of V. songaricum under reduced irrigation.

Valorization of Vineyard By-Products to Obtain Composted Digestate and Biochar Suitable for Nursery Grapevine (Vitis vinifera L.) Production

Although compost and biochar received high attention as growing media, little information is available on the potential of vineyard by-products for the production and use of composted solid digestate (CSD) and biochar (BC). In the present study, two experiments are reported on CSD and BC mixed with commercial peat (CP) for grapevine planting material production. Four doses (0, 10%, 20%, 40% vol.) of CSD and BC were assessed in the first and second experiment, respectively. CSD mixed at a dose of 10% recorded the highest values of shoot dry weight (SDW) and a fraction of total dry biomass allocated to shoot (FTS), both cropping bench-graft and bare-rooted vine. On the other hand, CSD mixed at a dose of 40% displayed the highest values of SDW and FTS, cropping two-year-old vine. BC used at a dose of 10% improved SDW, root dry weight, total dry weight, FTS, shoot diameter, and height on bare-rooted vine. The present study shows that CSD and BC, coming from the valorization of vineyard by-products, can be used in the production of innovative growing media suitable for nursery grapevine production. Further studies are needed to assess the combined applications of CSD and BC in the same growing media.

Mixed Cropping Effects on Yield, Manganese Influx, and Manganese Depletion in the Rhizosphere of Fodder Crops Grown in Manganese-Deficient Soil

To examine the possibility of managing manganese (Mn) deficiency through mixed cropping, berseem was grown as a monoculture and in mixed cropping with oats, ryegrass, or raya in a Mn-deficient soil under screen-house conditions. In no-Mn berseem monoculture treatment, shoot dry weight (SDW) and root length (RL) were, respectively, 33% and 45% of the maximum recorded values obtained with berseem grown in mixed cropping with ryegrass at 60 days of growth. Corresponding values of SDW and RL of berseem when grown with raya were 78% and 76% of the maximum, respectively. Even though berseem grown in mixed cropping with ryegrass and raya had smaller RL/SDW ratio and greater shoot growth rate than berseem grown as monoculture, it acquired a high shoot Mn concentration because of 3.8 times more Mn influx. A high Mn influx was the result of a high concentration gradient that developed because of depletion of Mn at the root surface.

A study on indicators and evaluation stages of aluminum tolerance in soybean

To determine an appropriate indicator and a suitable stage for evaluating tolerance of soybeans to aluminum (Al) toxin is one of the keys to effective breeding for the trait. Seventeen accessions selected as tolerant from a previous test program by using average membership index (FAi) as indicator, plus one tolerant (PI.416937) and one sensitive (NN1138-2) check, were assayed in sand culture pot experiments, totaling four experiments, each for evaluation at V3, V5, V7 and V9 stage, respectively, each in a randomized complete block design with three replications, and each genotype exposed to two Al levels (0 and 480 μM). The relative values of shoot dry weight (RSDW), root dry weight (RRDW), total plant dry weight (RTDW), total root length (RTRL) and total root surface area (RRSA) as the tolerance indicators as well as FAi were compared. All the indicators showed significant variation in Al tolerance among genotypes over and across the leaf stages, but Genotype × Stage interactions were significant only for RTRL and RRSA, indicating that they were less stable among stages than RTDW, RSDW and RRDW. Among the latter three, RTDW was chosen as the major indicator of Al tolerance due to its relatively better stability, higher correlation with other indicators and easier measuring procedure than the others. The seedling age applicable for screening was not definitive, but V5 appeared to compromise between time spent resulting from screening the relatively older seedlings at later stages and low variation among genotypes at a younger stage. The differences of Al tolerance among the tested accessions were further detected by using RTDW, and superior Al tolerant accessions identified were PI.509080 (South Korea), N23533 and N24282 (Northeast China) and PI.159322 (USA), comparable to the putative tolerant check PI.416937 (Japan) at all vegetative stages.

Simulation modelling of land suitability evaluation for dry season peanut cropping based on water availability in Northeast Thailand: evaluation of the MACROS crop model

Abstract. The MACROS crop model was evaluated for its utility to generate information on land suitability for dry season peanut cropping based on water availability at the regional scale in Khon Kaen Province, Northeast Thailand. The model was specific for the condition where crop growth is limited by water stress, and evaluated using both calibration and validation phases in sequence. In the model calibration, data sets from one peanut field experiment were used to calibrate some parameters to obtain the best agreement between experimental and simulated results. The model validation, in this study, consisted of a ‘validation A’, with emphasis on the accuracy and a ‘validation B’, with emphasis on the usefulness and relevance of the model. In the model validation A, data sets from peanut field experiments were used to validate the model under different conditions. Satisfactory agreements were found between the dynamics of observed and corresponding simulated values of shoot dry weight in every condition involved in this validation study. Also the simulated pod yields agree well with the field data. For the validation R, the model was further validated using data from 36 farm trials conducted at 5 different test sites. A high positive correlation (r= 0.91) existed between observed and simulated pod yields. Because of these satisfactory agreements between observed and corresponding simulated values, it was concluded that the model is valid and can be applied to Khon Kaen Province.