Weight Of Root Nodules Research Articles

Complex Growth Regulator Increases Alfalfa Seed Production

The effects of thermophilic methane fermentation products on alfalfa (Medicago sativa L.) growth, nitrogen-fixing activity, and seed production were studied in pot and field experiments. Plant treatment with the preparation at the stages of stooling and flower bud formation resulted in an increase in the root nodule weight and their nitrogen-fixing activity, the accumulation of cytokinins (zeatin and zeatin riboside), and an increase in the green mass yield and protein content, especially at a low (0.25 of the full rate) mineral nitrogen rate. Crop seed production was considerably improved during the first (pot experiments) and second (field experiments) growing seasons. The conclusion was drawn that the causes for improved alfalfa seed production were the effects of group B vitamins, phytohormones, their interaction, and the switching of metabolic pathways toward cytokinin synthesis.

Performance of chickpea (Cicer arietinum) as influenced by moisture management and zinc fortification in pearlmillet (Pennisetum glaucum) chickpea cropping system under limited moisture conditions

A field experiment was conducted during the winter (rabi) season of 201213 and 201314 at research farm of Indian Agricultural Research Institute, New Delhi, to determine the effect of moisture management and direct as well as residual effect of zinc fortification on performance of chickpea (Cicer arietinum L.) in pearlmillet [Pennisetum glaucum (L.) R. Br.]chickpea cropping system under limited moisture conditions. Different moisture- management practices resulted in significantly higher plant height, dry-matter accumulation, number and weight of root nodules, number of branches, pods/plant, grains/pod and 1,000-grain weight compared to flat planting. How- ever, flat bed planting recorded significantly higher values of root parameters than crop residue-applied treat- ments. Significantly higher grain (2.48 t/ha) and stover (5.98 t/ha) yields with water productivity of 116.9 kg/m3 were observed under flat bed with 5.0 t/ha crop residue over flat bed without residue and flat bed with 2.5 t/ha crop residue. Narrow bed and furrow with 2.5 t/ha crop residue cover fetched significantly higher production efficiency, whereas, flat bed with 5.0 t/ha crop residue recorded significantly higher Zn content in grain and stover of chickpea than rest of the moisture-management practices. Under direct-applied zinc fortification treatments in- creasing levels of zinc up to 5.0 kg/ha significantly enhanced the growth parameters, yield attributes, yield, water productivity, production efficiency and Zn content in both grain and stover of chickpea. Under residual effect of zinc fortification, plant height, number and dry weight of root nodules, root parameters, number of secondary branches, pods/plant, test weight, stover yield, water productivity and production efficiency of chickpea were in- creased significantly only up to 2.5 kg Zn/ha. However, application 5.0 kg Zn/ha to pearlmillet recorded signifi- cantly higher dry-matter accumulation, number of primary branches, grain yield (2.32 t/ha) and content of Zn in grain as well as in stover than lower levels.

Growth and development of groundnut (Arachis hypogaea) under foliar application of panchgavya and leaf extracts of endemic plants

A field experiment was conducted at Regional Research Station, CAZRI, Jaisalmer during kharif 2006 and 2007 to evaluate the efficacy of foliar applied panchgavya on the physiological growth, nutrient uptake, yield and economics of groundnut ( Arachis hypogaea) with and without mixing leaf extracts of neem ( Azadirachta indica), datura ( Datura metel) and tumba ( Citr ullus colocynthis). The results of the experiment revealed that foliar appli- cation of panchgavya + neem leaf extract (NLE) recorded significant improvement in chlorophyll content, nitrate reductase activity, root nodule weight, leaf area index, dry matter accumulation, nutrient content and uptake of groundnut when compared with control and panchgavya alone. Yield attributes (pod weight, pod index, kernel index, shelling per cent) and harvest index were also recorded significantly higher with panchgavya + NLE. The pod, haulm and biological yield increased by 54, 25 and 39% with foliar application of panchgavya + NLE over the control. Maximum net return (Rs 45,399/ha) and B: C ratio (2.19) was recorded with foliar application of panchgavya + NLE over other sources. Foliar application at branching (35 DAS) and flowering (55 DAS) re- corded significantly higher growth and yield of groundnut, net return (Rs 42,880/ha) and benefit: cost (2.06) than foliar application of the sources either one of these two stages.

The Effect of Nitrogen Fertilization and Population Density of the Field Bean (Vicia faba L. minor) of Indeterminate and Determinate Growth Habit on the Symbiosis with Root Nodule Bacteria and on the Seed Yield

AbstractField beans of indeterminate (cv. Nadwiślański) and determinate (cv. Tibo) growth habits were grown on field plots with a density of 20, 40 and 80 plants m−2 at two levels of nitrogen fertilization: low (20 kg N ha−1) and very high (150 kg N ha−1). At the phase of intense pod growth the number and the dry matter weight of root nodules as well as their nitrogenase activity and some features of the plants growth were determined, and in the period of ripeness the components of seed yield were established.It was found that increased density of sowing as well as the high level of nitrogen fertilization inhibited the growth and development of root nodules and limited their nitrogenase activity in both cultivars. Plants of both varieties were characterized by a similar potential of forming the root nodules, however, in plants of the cv. Tibo the nitrogenase activity of nodules was much lower than in the cv. Nadwiślański.Increased population density of the plants has in both varieties given increased seed yield when calculated per m2 of the soil, compensating in excess the depression of the seed yield from one plant. Such compensation did not occur in the case of the depression of nitrogen fixation under intense nitrogen fertilization.

The Effect of Detopping the Field Bean Plants (Vicia faba L. minor) and Lack of the Pod Setting on the Symbiosis with Root Nodule Bacteria

AbstractThe plants of field bean var. Nadwiślaνski were detopped after about 1 month since the beginning of flowering and after that all flower buds were removed from some plants. The effect of a change in the trophic balance on the setting and subsequent growth of root nodules was studied.The removal of pods had the greater effect on the increase in the weight of the remaining organs than the detopping of plants. Detopping retarded the ageing of the plants and delayed the phase of the greatest reduction of the number of pods. The detopping of plants revealed their considerable compensative possibilities in terms of production of the pod weight and the potential of leaves for biomass production. The data obtained indicate that plant detopping may disturb the root–bacteria exchange of signals, necessary to initiate the nodule development, while the further growth of nodules depends, above all, on the amount of available photosynthates.A very high correlation between the dry weight of the whole plant to the dry weight of leaves ratio and the weight of nodules was observed. It proves the importance of the trophic balance of the plant for the root nodule weight production.

Influence of combined nitrogen level andEucalyptus competition on dinitrogen fixation in nodulatedCasuarina

Experiments were conducted to determine the effect on biological dinitrogen fixation byCasuarina of available nitrogen (N) in the substrate and competition by interplantedEucalyptus. In these experiments, combined N was applied to the plants after nodules were developed and functioning. Both environmental factors, nitrate and competition, were observed to influence biological dinitrogen fixation byCasuarina, but not yield (total dry weight). In one experiment, the proportion of nitrogen derived byCasuarina from atmospheric fixation (pNdfa) was observed to be inhibited by potassium nitrate in a linear fashion. However, substrate N did not significantly affect the weight of root nodules. Thus nodule dry weight was not highly correlated with the proportion of nitrogen fixed. In a second experiment, the presence of a non-fixing interplanted species,Eucalyptus, increased dinitrogen fixation inCasuarina.Casuarina interplanted withEucalyptus obtained a greater proportion of its nitrogen (94.75%) from fixation than didCasuarina grown alone (86.68%) suggesting that competition for substrate N influences the proportion of nitrogen fixed by this actinorhizal plant.

Responses to sequential exposure to SO2 and salinity in soybean (Glycine max L.)

Soybean plants (Glycine max L. cv. Buchanan) were subjected to one of three levels of salinity preteatment (with electrical conductivities of 0.7, 4.4 and 6.5 dS m−1) and then exposed to one of three concentrations of SO2 (1, 145 and 300 bl l−1 for 5 h d−1), or vice versa. Each stress episode lasted 3 weeks. Both salinity and SO2 deecreased leaf area, root and shoot dry weight and the fresh weight of root nodules. SO2 induced an increase in the shoot: root ratio and leaf chlorophyll concentrations. Low salinity pretreatment protected plant growth from SO2 injury, probably by decreasing SO2 uptake by increasing stomatal resistance. However, high salinity-treated plants, despite also showing stomatal closure, were severely injured by subsequent SO2 exposure. Prior exposure to SO2 caused plants to become more vulnerable to salt injury. Plants pretreated with high SO2 were killed after 12 days of high salt stress. These data suggest that the compensatory mechanisms and predisposition characteristics of salinity and SO2 largely depend upon the stress levels used.

Effects of SO 2 and salinity on nitrogenase activity, nitrogen concentration and growth of young soybean plants

Young soybean plants ( Glycine max L.) were exposed to three SO 2 concentrations (2, 110 and 250 ppb) and two levels of soil salinity (no added NaCl and 27 mM NaCl) in a factorial experiment for 16 days. SO 2 exposure was for 5 hr day −1. Exposure to 250 pbb (high) SO 2 decreased the number and weight of root nodules, suppressed nitrogenase activity, and reduced shoot and root nitrogen concentrations, whereas 110 ppb (low) SO 2 usually had no effect on these parameters. High and low SO 2 concentrations increased the shoot-to-root ratios by reducing root growth and stimulating shoot growth, respectively. Soil salinity decreased root nodulation and N-fixation, but it ameliorated SO 2-induced injury. Twelve days after exposure to SO 2, foliar injury was apparent in the treatment of high SO 2 alone but was negligible in the high SO 2 and salinity treatment. The reduced SO 2 injury under saline conditions was probably achieved by decreasing SO 2 uptake through stomatal closure.

Effect of CCC on Shoot Growth, Nodulation, Nitrogenase Activity, and Contents of Nitrogen, Ureides, Sugars and Starch in Mung Bean (Vigna radiata [L.] Wilczek var. Guj-2)

Summary Effect of (2-chloroethyl) trimethyl ammonium chloride (CCC) on shoot growth, nodulation, nitrogenase activity, and contents of nitrogen, ureides, sugars and starch in mung bean ( Vigna radiata L. Wilczek var. Guj-2) was studied. CCC application at 1000ppm and 1500ppm markedly reduced the extension growth of the shoot system. CCC at 1000ppm (1000 mg · dm -3 ) significantly increased the number as well as dry weight of root nodules and activity of nitrogenase (acetylene reduction). The contents of total nitrogen, ureides, sugars and starch in shoot and root systes were also increased considerably in response to CCC (1000ppm) treatment. The present study suggests that CCC application may lead to the availability of more photosynthate for nodule formation and nitrogen fixation in mung bean.

Effects of Meloidogyne spp. on growth, nodulation and nitrogenase activity of siratro ( Macroptilium atropurpureum (DC) Urb.)

Top growth of Siratro ( Macroptilium atropurpureum (D.C.) Urb.) was not significantly altered by infestation with several Meloidogyne spp. Root-nodule weight and nitrogenase activity in nematode-infected plants were significantly increased compared with nematode-free plants. Nitrate reductase of nodule-cytosol was 10 times higher in nematode-infested nodules compared with nematode-free nodules. Nematode infestation did not significantly influence enzyme activity levels that govern fixed N transformations within nodules. However, enzume activity governing ureidoglycolate transformations and glyoxylate metabolism were greatly decreased by nematode infestation. Ureide and pyruvate contents of nematode-free nodules were significantly greater than those nodules of nematode-infested plants. Nitrate and amine-amide contents of noninfected nodules were significantly less than those in nematode-infected nodules. Nodule cytosol contents of α-ketoglutarate, nonconjugate P, K, Ca, Mg and Na were not changed by nematode infestation. Nematode infestation reduced fibrous root growth and caused galls on both roots and nodules. Nematode invasion of nodules induced development of giant multinucleate cells in the peripheral parenchyma adjacent to vascular bundles, the absence of lipophilic vacuoles in rhizobial engorged cells, and the predominance of rod-shaped rather than pleomorphic bacteroids.

EFFECT OF MOLYBDENUM APPLICATIONS ON LEGUMINOUS HAY CROPS IN PRINCE EDWARD ISLAND

Seed treatments of molybdenum were found to increase yields of early red clover on three soil types in Prince Edward Island. Plots receiving 8 or more ounces of molybdenum per acre were significantly better than the control plots. Applications of 1000 lb. and 2000 lb. of ground limestone per acre had no effect on the yields of molybdenum-treated clover but the uptake of molybdenum by plants was highest where the 2000 lb.-per-acre rate was applied. The influence of added molybdenum on clover root nodule formation was determined on one soil type. Eight ounces of molybdenum per acre gave a significant increase in the weight of root nodules on the treated plants.