Development Of Wheat Plants Research Articles

Growth, physiology and yield of durum wheat (Triticum durum) treated with sewage sludge under water stress conditions.

In arid and semi-arid areas, low soil fertility and water deficit considerably limit crop production. The use of sewage sludge as an organic amendment could contribute to the improvement of soil fertility and hence the agronomic production. The study aims to highlight the behaviour of durum wheat to the application of sewage sludge associated with water stress. The assessment focused on morphophysiological parameters of the wheat plant and yield. Under greenhouse conditions, the variety Mohamed Ben Bachir was treated by four water stress levels (100 %, 80 %, 50 % and 30 %). Each stress level comprised five fertilizer treatments: 20, 50 and 100 t/ha of dry sludge, 35 kg/ha of urea, and a control with no fertilization. Results revealed a significant loss in water content and chlorophyll a in leaves. Water stress negatively affected the development of wheat plants by reducing significantly seed yield, leaf area and biomass produced. Plant’s responses to water stress manifested by an accumulation of proline and a decrease in total phosphorus. However, the increasing doses of sewage sludge limited the effect of water stress. Our findings showed an increase in the amount of chlorophyll pigments, leaf area, total phosphorus, biomass and yield. In addition, excessive accumulation of proline (1.11 ± 1.03 µg/g DM) was recorded as a result of the high concentration of sludge (100 t/ha DM). The application of sewage sludge is beneficial for the wheat crop, but the high accumulation of proline in plants treated with high dose of sludge suggests to properly consider this fact. The application of sludge should be used with caution in soils where water is limited. Because the combined effect of these two factors could result in a fatal osmotic stress to crop development.

Desenvolvimento inicial de trigo sob doses de nitrogênio em Latossolo Vermelho de Cerrado

As condições de solo, clima, topografia e variedades adaptadas, têm favorecido o cultivo de trigo no Cerrado; contudo, no que concerne à adubação nitrogenada, ela é responsável pelo incremento de produção. Assim, o objetivo deste estudo foi avaliar o desenvolvimento inicial e a produção de massa seca de plantas de trigo cv. Guamirim adubado com nitrogênio em Latossolo Vermelho do Cerrado. O experimento foi conduzido em casa de vegetação da Universidade Federal do Mato Grosso - Campus Universitário de Rondonópolis, em vasos com capacidade para 5 dm³. O delineamento experimental foi o inteiramente casualizado com seis doses de nitrogênio (0, 80, 160, 240, 320 e 400 mg dm-3), cinco repetições e cinco plantas por vaso. Os períodos de avaliações foram: 26, 33, 40 e 47 dias após a emergência, determinou-se: número de folhas e perfilhos, altura de planta, massa seca da parte aérea e raízes. A adubação nitrogenada influencia o desenvolvimento das plantas de trigo em todos os períodos avaliados. As melhores respostas do trigo à adubação nitrogenada ocorrem nas doses entre 80 a 195,6 mg dm-3.

Tricin biosynthesis during growth of wheat under different abiotic stresses

In plants, O-methylation is mediated by an enzyme family of O-methyltransferases (OMTs) that transfer the methyl groups from the methyl donor, S-adenosyl-L-methionine (AdoMet) to suitable phenolic acceptor molecules. In a previous study [1], a flavonoid OMT (TaOMT2) was isolated and characterized from wheat (Triticum aestivum L.) leaves. Its novel gene product catalyzes three sequential O-methylations of the flavone tricetin (5,7,3′,4′,5′-pentahydroxyflavone) to its 3′-monomethyl-(selgin)→3′,5′-dimethyl-(tricin)→3′,4′,5′-trimethyl (TMT) ether derivatives, with tricin being the major product of the reaction. In this report, the biological significance of tricetin methylation was investigated by measuring the OMT activity, its expression level, and the accumulation of its major product (tricin) at different stages of development of wheat plants exposed to different abiotic stresses such as cold, salt and drought. The results showed that tricin accumulates mostly in wheat inflorescences under normal conditions compared to leaves and other developmental stages. Tricin accumulation was associated with increased TaOMT2 expression level and its enzyme activity, suggesting a possible de novo synthesis of the enzyme at this important developmental stage. This phenomenon may be attributed to the putative role of tricin in protecting seeds against biotic and abiotic stresses. The functions of tricin during growth and development of wheat and the importance of tricetin methylation during abiotic stresses are discussed.

Plant growth promoting activity of an auxin and siderophore producing isolate of Streptomyces under saline soil conditions

A biocontrol Streptomyces isolate (C) was tested for its plant growth promoting qualities under saline conditions. Exposure to elevated osmotic strengths up to 300 mM NaCl increased dry weight and cfu/ml significantly. The isolate C produced indolyl-3-acetic acid (IAA) into the medium in the amount of 2.4 μg/ml. The amount of auxin increased after adding salt and reached to 4.7 μg/ml in 300 mM NaCl. Biosynthesis of siderophore was detectable and increased in presence of NaCl. Streptomyces isolate C showed good solubilization of tricalcium phosphate in culture medium with 92 mg/l. Solubilization decreased in presence of NaCl. Soil treatment with isolate C increased the growth and development of wheat plant in normal and saline conditions. In this treatment there were significant increases in germination rate, percentage and uniformity, shoot length and dry weight compared to the control. Applying the bacterial inocula increased the concentration of N, P, Fe and Mn in wheat shoots grown in normal and saline soil, but had non-significant effect on other micro and macronutrients concentrations. Results of this study show that Streptomyces isolate C has potential to be utilized as biofertilizer in saline soils.

Efficacy of rhizobacterial strains encapsulated in nontoxic biodegradable gel matrices to promote growth and yield of wheat plants

One of the successful, safe and effective methods to introduce bioinoculants in soil is encapsulation of cells in biodegradable gel matrices which not only releases the microorganisms to the soil gradually but also helps to increase the survival rate by protecting them against many environmental stresses. Two bacterial strains viz. Pseudomonas fluorescens BAM-4 and Burkholderia cepacia BAM-12 were immobilized using sodium alginate and alginate + skim milk as carrier to check the phosphate solubilization in vitro and were found to have significantly higher activity than control. Their efficacy was also tested in vivo on wheat plants growth in semi arid environmental conditions in pots. The seed inoculation of rhizobacteria along with hardly soluble TCP and RP significantly ( P < 0.05) enhanced the overall development of wheat plants in free and immobilized cell states in comparison to control. With a few scattered exceptions, plants amended with bacterial strains showed significantly ( P < 0.05) better performance than the plants having chemical fertilizer, SSP and biofertilizer, biogold. When the two insoluble P sources were compared, TCP was found much better than RP treatments. Performance wise, B. cepacia BAM-12 was found to be the best.

Use of human wastes oxidized to different degrees in cultivation of higher plants on the soil-like substrate intended for closed ecosystems

To close mass exchange loops in bioregenerative life support systems more efficiently, researchers of the Institute of Biophysics SB RAS (Krasnoyarsk, Russia) have developed a procedure of wet combustion of human wastes and inedible parts of plants using H 2O 2 in alternating electromagnetic field. Human wastes pretreated in this way can be used as nutrient solutions to grow plants in the phototrophic unit of the LSS. The purpose of this study was to explore the possibilities of using human wastes oxidized to different degrees to grow plants cultivated on the soil-like substrate (SLS). The treated human wastes were analyzed to test their sterility. Then we investigated the effects produced by human wastes oxidized to different degrees on growth and development of wheat plants and on the composition of microflora in the SLS. The irrigation solution contained water, substances extracted from the substrate, and certain amounts of the mineralized human wastes. The experiments showed that the human wastes oxidized using reduced amounts of 30% H 2O 2: 1 ml/g of feces and 0.25 ml/ml of urine were still sterile. The experiments with wheat plants grown on the SLS and irrigated by the solution containing treated human wastes in the amount simulating 1/6 of the daily diet of a human showed that the degree of oxidation of human wastes did not significantly affect plant productivity. On the other hand, the composition of the microbiota of irrigation solutions was affected by the oxidation level of the added metabolites. In the solutions supplemented with partially oxidized metabolites yeast-like microscopic fungi were 20 times more abundant than in the solutions containing fully oxidized metabolites. Moreover, in the solutions containing incompletely oxidized human wastes the amounts of phytopathogenic bacteria and denitrifying microorganisms were larger. Thus, insufficiently oxidized sterile human wastes added to the irrigation solutions significantly affect the composition of the microbiological component of these solutions, which can ultimately unbalance the system as a whole.

Influence of nitrogen on the expression of TaDof1 transcription factor in wheat and its relationship with photo synthetic and ammonium assimilating efficiency

Nitrogen is a crucial macronutrient needed in the greatest amount of all mineral elements required by plants. Development of crop varieties with high nitrogen use efficiency (NUE) is imperative for sustainable agriculture. Understanding how plant genes respond to different nitrogen conditions is essential for formulating approaches, for manipulating genes, for improving NUE. In the present study we analyzed the activity of three different enzymes involved in nitrogen assimilation viz., GS, GOGAT and GDH along with physiological parameters like chlorophyll variable yield (Fv/Fmax), photosynthesis rate and total chlorophyll content at four different growth stages of wheat plant development under different nitrogen treatments. For this study two different wheat varieties UP-2644 and Raj-4097 having high and low protein content, respectively in the grains were chosen. Gene expression profile of a Dof transcription factor (TaDof1 of wheat) was also included in the study to assess its role in nitrogen metabolism. Densitometry analysis at S(2) and S(3) stage of wheat spikes of both the wheat varieties grown at different nitrogen treatments showed that TaDof1 expression was up-regulated in low nitrogen treatment. In S(3) stage, in high protein content wheat variety UP-2644, TaDof1 expression was elevated in low and normal nitrogen treatment as compared to high nitrogen treatment. The gene expression profile of Dof 1 was found to coincide with the enzyme activities of GS, GOGAT at the S(3) stage. The activities of these enzymes were prolonged in the high protein content variety. Since, Dof transcription factor(s) have been previously reported to control the expression of genes involved nitrogen assimilation i.e., GS and GOGAT and may be the elevated expression of Dof 1 at the grain filling stage over expresses the GS and GOGAT genes thereby prolonging their activities.

Azospirilli of Uzbekistan Soils and their Influence on Growth and Development of Wheat Plants

Associative nitrogen-fixing bacteria have been isolated, which were related to Azospirillum genus, by their morphological–cultural and physiological–biochemical ability to grow in microaerophilic conditions, as well as by a number of phenotypic traits. They comprised two species, namely, Azospirillum brasilense and Azospirillum lipoferum. Azospirilli strains displayed a varying salt resistance on potato medium containing a range of NaCl concentrations from 100 to 800 mM. The decrease in the nitrogen-fixing activity of azospirilli was detected starting from 200 mM NaCl. The biomass of the inoculated local varieties of wheat, Unumdor Bugdoi and Karlik 85, in microvegetation experiments exceeded the biomass of control plants by 20–50%. During the vegetation, some azospirilli strains formed spontaneous nodules on the wheat roots.

Crop residue position and interference with wheat seedling development

Unweathered crop residues can produce growth-inhibiting substances, stimulate pathogen growth, and immobilize nutrients. The location of seed relative to residue may be an important factor in the early health of a crop. This greenhouse study simulated sowing conditions possible under annual dryland winter wheat ( Triticum aestivum L.) production to evaluate the likelihood of inhibitory effects. We placed newly harvested, unweathered winter wheat residue on the soil surface, mixed with the seed, immediately above the seed, or 3 cm below the seed. Treatments using a plastic residue substitute and treatments using pasteurized soil and residue provided comparisons to the natural soil and wheat residue. Residue mixed with or placed above the seed caused a temporary delay in emergence. Since this occurred with both wheat and plastic residue, the delay is explained by the physical impedance of coleoptile growth. Wheat residue 3 cm below the seed reduced the height and rate of wheat plant development, indicating a biological inhibitory effect of the wheat residue. This reduction in height and development rate at 20 days after planting did not occur when the soil and residue were pasteurized. We conclude that winter wheat seedling growth can be inhibited if roots encounter unweathered residues.

Viability of VA-mycorrhizal fungi following soil solarization and fumigation

Two field experiments were conducted to examine the effect of soil solarization on the survival of arbuscular mycorrhizal (AM) fungi and root colonization of three crops. The experiments were carried out in a loamy sand soil (Rehovot) and a silty soil (Bet She'an Valley). For both experiments, assessment of indigenous AM fungal populations by the most probable number (MPN) method indicated that populations were reduced to zero after 2 or 4 weeks of solarization treatment. However, Glomus intraradices inoculum applied to the soil prior to solarization remained viable even after 8 weeks of solarization. After soil fumigation with methyl bromide both indigenous and applied AM fungi were nondetectable. Percentage root colonization by the indigenous AM fungal populations, together with plant-growth parameters, were assessed for three crops: onion and wheat (Rehovot), and carrot (Bet She'an). When sown on solarized field plots, onion and carrot seedlings showed a plant growth retardation, whereas wheat showed an increased growth response. Root colonization by indigenous AM fungi was not evident until 6 weeks after seedling emergence. Fumigation with methyl bromide reduced root colonization by indigenous AM populations, and reduced onion and wheat plant development at early growth stages. In a laboratory experiment, a temperature of 45° C for up to 24 h did not affect AM spore viability, indicating that temperatures reached during the solarization treatment cannot solely account for the reduced AM fungi viability in the field. Apparently, soil solarization temporarily delays root colonization by indigenous AM fungi until 6-8 weeks after plant emergence.

Effects of phosphorus and drought stresses on dry matter and phosphorus allocation in wheat

Abstract The effect of phosphorus (P) and soil water availability (W) on the growth and development of wheat plants (Triticum aestivum L. cv. Minaret) was studied in a pot experiment. Four levels of P supply (0, 15, 30, and 100 μgP/g soil) were applied before sowing. Thirty‐four days after sowing (DAS), the pots were kept near 100% of field capacity (FC). From 34 DAS until one week before anthesis (67 DAS), half of the pots were maintained between 60–70% FC. Control pots were kept at 85–95% FC by weighing and watering the pots every two to three days. Shoots were harvested four times before anthesis and twice after. At each harvest, dry matter and P accumulation were measured in leaves, stems, and ears. In this study, thermal time until anthesis was inversely related to the level of P application. Phosphorus additioning affected the allocation of biomass and P in aerial plant organs. Plants growing only with soil P showed a delay in the allocation of dry matter and P into leaves and stems with respect to ...

Phosphorus Deficiency Affects the Early Development of Wheat Plants

AbstractThe effect of phosphorus nutrition on the development of wheat plants, was studied. Phosphorus deficiency increased the duration of the phyllochron when the concentration in shoots was less than 0.8 %. Phosphorus concentration in shoots appeared to be a good indicator of the effect of plant phosphorus status on wheat development.

The setting of rates of development of wheat plants at crop emergence: Influence of the environment on rates of leaf appearance

SummaryExamination of the time courses, expressed in terms of accumulated temperature over 0°C, of leaf appearance of fifteen sowings of winter wheat, including five cultivars, over three seasons at Auchincruive, revealed several examples of bi‐linear rather than linear responses. Stepwise linear regression analysis, varying the temperature threshold by intervals of 1°C, showed that a linear relationship could be obtained for each sowing, but the appropriateness of this analysis is questioned. An alternative interpretation, that such changes in rate do have biological rather than purely statistical significance, is supported by the fact that, when they occurred, they coincided with the change in rate of spikelet initiation by the stem apex. Furthermore, similar relationships between leaf appearance and reproductive development have been demonstrated for perennial ryegrasses. Analysis of each sowing also revealed the existence of sub‐populations of plants with different rates of leaf appearance and final leaf numbers, but with synchronous phenologies. These findings are discussed in relation to the coordination of the development of apex and leaves, and the environmental cues required to ensure this coordination.

Influence of Tillage Depths and P‐Fertilizer Application Rates on the Yields of Annual Cropped Winter‐Grown Wheat1

AbstractBecause of different climatical conditions during the growing season from those of reported experiments in literature and the relatively few data about annual cropped winter‐grown wheat (Triticum aestivum L.) yield response to depth of tillage and to incorporation of previously broadcasted P‐fertilizer, a 2‐year field trial was conducted to evaluate the effects of three tillage depths, 10, 20, and 40 cm; and three P‐fertilizer rates on grain yields and dry matter production. The three P‐fertilizer rates were: no P‐fertilizer, 12 kg P/ha per 10 cm depth of tilled soil, and a flat 60 kg P/ha rate.The field trial had a randomized split plot design with four replications and was simultaneously conducted on two soils of different texture.Grain yields, dry matter production, and P‐uptake over 2 years were not influenced by depths of tillage. Initial development of wheat plants was better on shallow tilled soil. Added P‐fertilizer markedly increased grain yields, dry matter production, and P‐uptake. P‐fertilizer rates based on volume of tilled soil were as effective as the flat P‐fertilizer rate. Dry matter production response to P‐fertilizer was influenced by soil texture, indicating limiting P‐availability with decreasing clay content of soil.From the data obtained it can be concluded that increasing depth of tillage has no significant effect on annual cropped winter‐grown wheat yields and secondly that there is no need to incorporate P‐fertilizer deeper than the top soil layer of 10 cm.Therefore, if plowing a wheat stubble becomes necessary, P‐fertilizer rate can be based on the P‐availability of the sampled top soil layer after plowing and adjusted to the depth of the planned seedbed preparation to keep P‐availability at the recommended level for wheat growing.

Soil Temperature and Wheat Straw Mulch Effects on Wheat Plant Development and Nutrient Concentration1

AbstractHard red winter wheat (Triticum aestivum L.) was grown with and without wheat straw mulch on the soil surface both in a growth chamber with controlled soil temperatures and in the field where soil temperatures were measured at the crown depth. Concentrations of N, P, K, Ca, Mg, Fe, Zn, Mn, and Cu in the plant were determined at the end of tillering and at heading.Wheat plants grown with soil temperatures below 10C for 50 days, whether in the growth chamber or in the field, had 2 to 3 fewer tillers per plant and 0.5 to 1.2 fewer heads per plant than plants grown with soil temperatures below 10C for only 15 days. Soil temperature seemed not to affect weight per head or total plant weight. Cooler temperatures reduced the concentrations of only K and Fe in the growth chamber at heading and N in the field at heading. When mulched and bare soil temperatures were identical, mulch did not reduce numbers of tillers or heads per plant, plant nutrient concentration, total uptake of any nutrient, or final grain yields in growth chamber or field. The concentration of all nutrients but Cu changed as the plant developed showing the necessity of knowing growth stages of plants if nutrient concentrations are to be compared.

Timing of insecticidal sprays to control the wheat-bulb fly, Leptohylemyia coarctata (Fall.)

The timing of sprays in relation to the stage of development of wheat plants and larvae of the wheat-bulb fly, Leptohylemyia coarctata (Pall.), was studied in the laboratory and field. The main growth of young wheat plants was of the centre shoot and such plants died when the centre shoot meristems were destroyed. Older plants survived by growth of lateral shoots. Sprays of dimethoate, trichloronate and thionazin applied before the larvae had emerged did not kill many larvae in the soil, and only insecticide that entered the plants was effective. Severely attacked two-leaf plants yielded little, whether sprayed or not, whereas three-leaf plants sprayed in early March gave a worth-while increase in yield: older plants had enough shoots to give moderate yields even when not sprayed.In a large field trial, plants from two sowing dates, 22nd October and 1st November, were both at the late two-leaf stage of growth in late February. Wheat-bulb fly larvae had entered nearly all the shoots but plants from both sowings had buds or small lateral growths hidden beneath the outer leaves. The yields of October-sown plots sprayed on 22nd February, 2nd March, 9th March or 16th March were 28·2, 28·8, 25·5 and 23·2 cwt. grain per acre, respectively, (yield of unsprayed plots = 18.9 cwt./acre) and of November-sown plots were 31·0, 27·5, 17·9 and 14·9 cwt. per acre, respectively, (yield of unsprayed plots = 116 cwt. per acre). Sprays had most effect when applied soon after larvae had entered the plants. Spraying severely-attacked late two-leaf to three-leaf plants gave the greatest benefits because these plants recovered by growth of lateral buds or small lateral shoots.

Competition for light and its effect on leaf and spikelet development of wheat plants

The effect of changes in the light environment of wheat plants at different stages in their growth was examined by growing single plants in tubes and changing the spacing of the tubes (population density) during development. Individual leaves on the main stem were reduced in both area and weight by transfer of the plants from high density to low density during the period from initiation of growth of the leaf on the apex to its appearance above the sheath. The number of fertile spikelets per ear was increased by transfer to low density in the period between formation of double ridges and ear emergence. It is suggested that the potential for grain yield of a wheat ear is affected by the light environment of the shoot at any stage before ear emergence.

Studies on the nitrogenous manuring of winter wheat

1. The problem of when to apply nitrogenous top-dressings to winter wheat has nover been satisfactorily solved. Detailed field and glasshouse experiments on the effects of nitrogenous manuring on the development of wheat plants, and a number of other experiments involving the nitrogenous manuring of wheat are described and the results discussed.2. Partial regression coefficients of grain yield on individual components of yield are used to show how variable is the relationship between grain yield and the components of yield.3. It is concluded that field experiments are never likely to determine an optimum time for nitrogen top-dressing because of the unpredictable relationships between individual yield components and grain yield, and because of the variation in response to nitrogen introduced by seasonal and environmental factors.

Development of Wheat Plants from Seminal Roots1

Agronomy JournalVolume 16, Issue 4 p. 261-268 Article Development of Wheat Plants from Seminal Roots1 Lowell F. Locke, Lowell F. LockeSearch for more papers by this authorJ. Allen Clark, J. Allen Clark Assistant Agronomist at Woodward, Oklahoma, Office of Dry Land Agriculture Investigations, and Agronomist in charge, Western Wheat Investigations, Office of Cereal Investigations, respectively.Search for more papers by this author Lowell F. Locke, Lowell F. LockeSearch for more papers by this authorJ. Allen Clark, J. Allen Clark Assistant Agronomist at Woodward, Oklahoma, Office of Dry Land Agriculture Investigations, and Agronomist in charge, Western Wheat Investigations, Office of Cereal Investigations, respectively.Search for more papers by this author First published: 01 April 1924 https://doi.org/10.2134/agronj1924.00021962001600040003xCitations: 6 1 Contribution from the Bureau of Plant Industry, U. S. Department of Agriculture, Washington, D. C. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume16, Issue4April 1924Pages 261-268 RelatedInformation