scholarly journals Rhizobial adhesives enhance nodule formation in sunn hemp

2021 ◽  
Author(s):  
Qulina Rai ◽  
Robin Choudhury ◽  
Pushpa Soti ◽  
Alexis Racelis

ABSTRACTInoculation of legume seed with rhizobacteria before planting is an efficient and convenient way of introducing effective rhizobacteria to soil vicinity of legume root and ensuring nitrogen fixation in cover cropped field. However, there are still challenges in identifying the proper seed coating technique to ensure microbial survival in adverse environmental conditions and maintaining the symbiotic relation with plants. The objectives of this study are firstly, to analyze the effectiveness of different sticking agents aiding inoculation of Bradyrhizobium japonicum L. in sunn hemp seeds to enhance root nodule formation. Secondly, to observe nodulation pattern over time as affected by the treatment and lastly to check if there is significant difference between main root and lateral root nodulation pattern due to the treatments. Two similar field studies were conducted in fall 2019 and summer 2020 using four sticking agents: water, peanut oil, 10% jaggery solution, and 40% gum arabic solution. The fall study showed no significant differences among total nodules across treatments, but percentage of active nodules was highest in the oil treatment and lowest in the water treatment. In the summer study, significantly higher total nodules were seen in the jaggery treatment and the lowest was in water treatment again, however, there were no differences in percentage of total active nodules across treatments. Interestingly, the trend across weeks showed gum arabic treatment exhibiting higher main root nodulation and jaggery treatment exhibiting higher lateral root nodulation. Overall, water as an adhesive was less effective in aiding nodulation compared to other treatments. Peanut oil and jaggery showed better performance as adhesives aiding active nodulation and could be more effective than gum arabic or water.

2002 ◽  
Vol 80 (9) ◽  
pp. 907-915 ◽  
Author(s):  
Walter F Giordano ◽  
Michelle R Lum ◽  
Ann M Hirsch

We have initiated studies on the molecular biology and genetics of white sweetclover (Melilotus alba Desr.) and its responses to inoculation with the nitrogen-fixing symbiont Sinorhizobium meliloti. Early nodulin genes such as ENOD40 serve as markers for the transition from root to nodule development even before visible stages of nodule formation are evident. Using Northern blot analysis, we found that the ENOD40 gene was expressed within 6 h after inoculation with two different strains of S. meliloti, one of which overproduces symbiotic Nod factors. Inoculation with this strain resulted in an additional increase in ENOD40 gene expression over a typical wild-type S. meliloti strain. Moreover, the increase in mRNA brought about by the Nod-factor-overproducing strain 24 h after inoculation was correlated with lateral root formation by using whole-mount in situ hybridization to localize ENOD40 transcripts in lateral root meristems and by counting lateral root initiation sites. Cortical cell divisions were not detected. We also found that nodulation occurred more rapidly on white sweetclover in response to the Nod-factor-overproducing strain, but ultimately there was no difference in nodulation efficiency in terms of nodule number or the number of roots nodulated by the two strains. Also, the two strains could effectively co-colonize the host when inoculated together, although a few host cells were occupied by both strains.Key words: ENOD40, Nod factor, Melilotus, Sinorhizobium, symbiosis.


PEDIATRICS ◽  
1950 ◽  
Vol 5 (4) ◽  
pp. 664-671
Author(s):  
B. M. KAGAN ◽  
M. NIERENBERG ◽  
D. GOLDBERG ◽  
A. MILZER

Table I summarizes most of the pertinent data in this report on the serum penicillin concentrations 12 and 24 hours after intramuscular injection of K penicillin G in peanut oil and beeswax, which is fluid at room temperature, and of three different procaine penicillin preparations. These three preparations are procaine penicillin G in sesame oil, procaine penicillin G in peanut oil with 2% aluminum monostearate, and procaine penicillin G in water with Na-carboxymethylcellulose. When they were given in a dosage of 8000 u./lb. to infants and children, weighing between 4.5 and 18.0 kg., there was no statistically significant difference in the serum levels obtained. A dosage schedule for these preparations is suggested for pediatric use. The aqueous preparation offers some advantages which are discussed. Experiences are reported which emphasize the necessity of avoiding intravenous administration of all these preparations.


2017 ◽  
Vol 53 (No. 2) ◽  
pp. 101-107 ◽  
Author(s):  
Liu Shao-Fang ◽  
Wang Guang-Jun ◽  
Nong Xiang-Qun ◽  
Liu Bin ◽  
Wang Miao-Miao ◽  
...  

The benefit of the entomopathogen Metarhizium anisopliae to early root development was evaluated. Two inoculating methods, conidia-suspension-drenching (T<sub>1</sub>) and conidia-coating (T<sub>2</sub>), were used when sowing peanut. The results showed that taproot length and lateral root number in T<sub>1</sub> significantly increased compared to the control (T<sub>0</sub>) in days 4–10 after treatment, whereas no significant difference was found between T<sub>2</sub> and T<sub>0</sub>. The fungal density by T<sub>1</sub> and T<sub>2</sub> fluctuated in the first 8 days, followed by a gradual decline. The ratio of the taproot length or lateral root number in T<sub>1 </sub>and T<sub>0</sub> was significant relative to the fungal persistence. It suggested that M. anisopliae promotes peanut root development and should be considered as important factor in plant protection besides pest controls.


2020 ◽  
Vol 198 ◽  
pp. 04036
Author(s):  
JI Xiaolei ◽  
XU Lanlan ◽  
YANG Guoping

Ecological slope protection is of great importance for preventing the water and soil loss on bare slopes, improving the ecological environment, and realizing the sustainable ecosystem development. The root-soil composite slope consisting of homogenous soil mass and oleander root system was taken as the study object. Based on the mechanics principle of soil reinforcement by roots in ecological slope protection, the influences of the lateral root quantity of plants and included angle between main root and lateral root on the slope protection were investigated via the finite element (FE) software ABAQUS. The simulation results show that the larger the quantity of lateral roots, the more obvious the displacement reduction of the soil mass on the slope surface will be. The slope protection effect varies with the root morphology, the included angle between main root and lateral root is an important factor influencing the slope protection effect of plants, and the slope protection effect at included angle of 30° is apparently superior to that at 90°. The research results can provide a theoretical support for the plant selection in the ecological slope protection.


2019 ◽  
Vol 24 (1) ◽  
pp. 135-163
Author(s):  
Jader Martínez Girón ◽  
Jenny Vanessa Marín-Rivera ◽  
Mauricio Quintero-Angel

Population growth and urbanization pose a greater pressure for the treatment of drinking water. Additionally, different treatment units, such as decanters and filters, accumulate high concentrations of iron (Fe) and manganese (Mn), which in many cases can be discharged into the environment without any treatment when maintenance is performed. Therefore, this paper evaluates the effectiveness of vertical subsurface wetlands for Fe and Mn removal from wastewater in drinking water treatment plants, taking a pilot scale wetland with an ascending gravel bed with two types of plants: C. esculenta and P. australis in El Hormiguero (Cali, Colombia), as an example. The pilot system had three upstream vertical wetlands, two of them planted and the third one without a plant used as a control. The wetlands were arranged in parallel and each formed by three gravel beds of different diameter. The results showed no significant difference for the percentage of removal in the three wetlands for turbidity (98 %), Fe (90 %), dissolved Fe (97 %) and Mn (98 %). The dissolved oxygen presented a significant difference between the planted wetlands and the control. C. esculenta had the highest concentration of Fe in the root with (103.5 ± 20.8) µg/g ; while P. australis had the highest average of Fe concentrations in leaves and stem with (45.7 ± 24) µg/g and (41.4 ± 9.1) µg/g, respectively. It is concluded that subsurface wetlands can be an interesting alternative for wastewater treatment in the maintenance of drinking water treatment plants. However, more research is needed for the use of vegetation or some technologies for the removal or reduction of the pollutant load in wetlands, since each drinking water treatment plant will require a treatment system for wastewater, which in turn requires a wastewater treatment system as well.


2017 ◽  
Vol 16 (1) ◽  
pp. 112-125 ◽  
Author(s):  
Natalie Wilhelm ◽  
Anya Kaufmann ◽  
Elizabeth Blanton ◽  
Daniele Lantagne

Abstract Household water treatment with chlorine can improve the microbiological quality of household water and reduce diarrheal disease. We conducted laboratory and field studies to inform chlorine dosage recommendations. In the laboratory, reactors of varying turbidity (10–300 NTU) and total organic carbon (0–25 mg/L addition) were created, spiked with Escherichia coli, and dosed with 3.75 mg/L sodium hypochlorite. All reactors had &gt;4 log reduction of E. coli 24 hours after chlorine addition. In the field, we tested 158 sources in 22 countries for chlorine demand. A 1.88 mg/L dosage for water from improved sources of &lt;5 or &lt;10 NTU turbidity met free chlorine residual criteria (≤2.0 mg/L at 1 hour, ≥0.2 mg/L at 24 hours) 91–94% and 82–87% of the time at 8 and 24 hours, respectively. In unimproved water source samples, a 3.75 mg/L dosage met relaxed criteria (≤4.0 mg/L at 1 hour, ≥0.2 mg/L after 24 hours) 83% and 65% of the time after 8 and 24 hours, respectively. We recommend water from improved/low turbidity sources be dosed at 1.88 mg/L and used within 24 hours, and from unimproved/higher turbidity sources be dosed at 3.75 mg/L and consumed within 8 hours. Further research on field effectiveness of chlorination is recommended.


2008 ◽  
Vol 22 (4) ◽  
pp. 584-590 ◽  
Author(s):  
Wilson H. Faircloth ◽  
Jason A. Ferrell ◽  
Christopher L. Main

Peanuts are not often used as a true oilseed crop, especially for the production of fuel. However, peanut could be a feedstock for biodiesel, especially in on-farm or small cooperative businesses, where producers can dictate the cost of making their own fuel. Field studies were conducted in 2005 and 2006 to assess low-cost weed-control systems for peanuts that would facilitate the economic viability of peanut biodiesel. Four preselected herbicide costs ranging from $25 to $62/ha and two application timings were compared with nontreated ($0/ha) and typical ($115/ha) herbicide programs for weed control and peanut oil yield. A peanut oil yield goal of 930 L/ha was exceeded with multiple low-cost herbicide systems in 3 of 4 site–yr. The main effect of application timing was only significant for a single site–year in which oil yield increased linearly with cost of the PRE and POST weed-control system. An herbicide cost of $50/ha, using PRE and POST applications, was consistently among the highest in oil yield, regardless of site–year, exceeding the typical (high value) programs in 3 of 4 site–yr. Use of reduced rates of imazapic (0.5× or 0.035 kg ai/ha) was detrimental in 2 of 4 site–yr. Weed control, and thus oil yields, were most dependent on species present at each location and not on input price. Data from this series of studies will allow researchers and entrepreneurs to more accurately assess the viability and sustainability of peanut biodiesel.


1997 ◽  
Vol 24 (5) ◽  
pp. 555 ◽  
Author(s):  
Christopher Pittock ◽  
Jeremy J. Weinman ◽  
Barry G. Rolfe

White clover was transformed with a tobacco basic chitinase promoter:GUS fusion. Basic chitinase promoter activity was detected by histochemical staining. Comparison of the spatial and temporal expression of the chitinase promoter-driven GUS gene in tobacco to that in white clover indicates that transcription from the promoter is induced by similar developmental and environmental response programs in each species. Wound-responsiveness of the white clover transgene was rapid and localised following mechanical and aphid (Family Aphididae) wounding. Developmental expression of the transgene during root morphogenesis reveals strong expression in tap and lateral root meristems but expression in lateral root meristems was observed only after the emergence through the tap root epidermis. No expression of the transgene was detected in the pericycle or the dividing cells of the developing lateral root. The expression of the tobacco basic chitinase promoter:GUS transgene in white clover was then used as a marker to examine the differences between the early developmental pathways leading to lateral root formation and those involoved in nodule formation in response to Rhizobium inoculation. Inoculation of the zone of emerging root hairs with a nodulation-competent Rhizobium strain ANU845(pRI4003), triggered transient transgene expression 2 to 4 h post-inoculation. No transgene expression was detectable after inoculation with purified Nod factor from strain ANU843. Our results suggest that lateral roots and nodules differ both in some of the mechanisms required to initiate cell division, and in their ongoing development after the emergence from the root epidermis.


2018 ◽  
Vol 30 (1) ◽  
pp. 234
Author(s):  
T. A. Bane ◽  
J. C. Bertels ◽  
K. M. Polkoff ◽  
M. Rubessa ◽  
M. B. Wheeler

Tissue engineering offers a viable alternative to bone grafts in repairing large bone defects. This involves using scaffolds of various sizes and shapes that contain stem cells and other osteoinductive molecules. The aim of this project was to evaluate the effects of vitamin K in osteogenic medium and its effect on the differentiation of adipose-derived stem cells (ASC) into osteoblasts. Vitamin K has been shown to increase bone mineral density by acting as a coenzyme in the γ-carboxylation of osteocalcin, a protein involved in bone mineralization (Weber 2001 Nutrition 11–12, 1024). Our hypothesis was that the presence of vitamin K in the osteogenic medium would positively influence the number of osteoblastic nodules formed. Swine ASC were isolated as described (Monaco et al. 2009 Open Tissue Eng. Regen. Med. J. 2, 20–33). The ASC were divided into 7 different treatments: 5 concentrations of vitamin K in the osteogenic medium (10, 50 100, 500, 1000 nM) plus 2 control treatments (osteogenic medium without vitamin K and a negative control, DMEM). The media was changed twice a week for 4 weeks. The experiment was replicated 6 times. At the end of the culture period, cells were stained with Alizarin Red S and Von Kossa. In each well, we counted the nodules and then divided them in 2 categories: formed and forming nodules. Data were analysed by analysis of variance using the generalized linear model (GLM) procedure of SPSS (IBM/SPSS, Armonk, NY, USA); the least significant difference (l.s.d.) post hoc test was used to perform statistical multiple comparison, and the α-level was set at 0.05. The results showed (in Table 1) that there was no positive effect on nodule formation when vitamin K was added to the medium; however, when 1000 nM vitamin K was added, nodule formation decreased. More experiments need to be conducted to determine if vitamin K can act synergistically with other vitamins to produce a significant role in ASC differentiation into osteoblasts. This preliminary experiment is the first step towards the analysis of the behaviour of ASC on scaffolds with vitamin K incorporated into their matrix. Table 1.The average number of formed and forming osteoblast nodules compared between treatment groups (SD in parentheses)


Agronomy ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 703
Author(s):  
Paul M. White ◽  
Gregory Williams ◽  
Howard P. Viator ◽  
Ryan P. Viator ◽  
Charles L. Webber

Sugarcane is commercially produced on 340,000 ha in the US and is valued at over $1 billion US annually. Cultural practices that improve sugarcane sustainability are needed to maintain yields in fields with degraded soils. Historically, leguminous rotation crops provided organic matter and biologically fixed nitrogen (N) for subsequent sugarcane crops. Currently, sugarcane is usually grown as a monoculture with only a short, 6-month fallow period. The objective of these field studies was to determine how growing cowpea (Vigna unguiculata (L.) Walp.) and sunn hemp (Crotalaria juncea L.) as cover crops during fallow affected the yield of subsequent sugarcane crops. A companion laboratory study investigated the decomposition rate of cover crops in soil at different temperatures. Cowpea and sunn hemp production produced 12.8 t/ha dry matter and 250 kg N/ha. Cowpea generally improved plant cane yields, but the effects of sunn hemp varied. However, neither cowpea nor sunn hemp reduced cane or sucrose yields consistently, and mineral N additions may have a role in mitigating yield gains or losses. Based on laboratory data, the average half-life for cowpea and sunn hemp would be 3 months. Overall, using legume cover crops should be viewed as an important component of sustainable sugarcane practices.


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