Ammonia–Nitrate Mixture Dominated by NH4+–N Promoted Growth, Photosynthesis and Nutrient Accumulation in Pecan (Carya illinoinensis)

Although ammonia–nitrogen (NH4+–N) and nitrate–nitrogen (NO3−–N) are the two main forms of N absorbed and utilized by plants, the preferences of plants for these forms are still unclear. In this study, we analyzed the growth, photosynthesis, and nutrients of pecan under different NH4+:NO3− ratios (0/0, 0/100, 25/75, 50/50, 75/25, 100/0) by indoor aerosol incubation. The results showed that additions of different N forms promoted the growth and development of pecan seedlings. When NO3−–N was used as the sole N source, it significantly promoted the ground diameter growth of pecan and increased the leaf pigment content and photosynthetic rate. The NH4+:NO3− ratio of 75:25 and NH4+–N as the sole N source significantly increased the soluble sugars in stems and roots, starch in leaves, stems and roots, soluble protein in leaves and stems, and soluble phenols in stems and roots. Additionally, the NH4+:NO3− ratio of 75:25 increased plant height, leaf number, root soluble protein, and leaf soluble phenol contents. In conclusion, regarding the physiological aspects of pecan growth, pecans are more inclined to use NH4+–N. Considering that the NH4+–N as the only N source may lead to nutrient imbalance or even toxicity, the NH4+:NO3− ratio of 75:25 was most favorable for the growth and development of pecan seedlings.

Effect of potassium supply on content of apple leaf phosphorus

Well-balanced mineral nutrition of apple trees is critical for fruit quality and storability. The seasonal changes of phosphorus and potassium leaf content were studied in the pot sand culture during the seasons of 2019 and 2020. The treatments comprised the application of the nutrient solution with different concentrations (0.00; 0.68; 1.36; 1.70; 2.04; 2.72; 3.40 g l-1). Leaves were analyzed on potassium and phosphorus content. The increase in potassium supply led to a striking increase in the content of apple leaf phosphorus above the optimal level. An approach to non-invasive detection of the impact of the nutrient imbalance based on hyperspectral reflectance imaging has been proposed.

Comparison of Biochemical and Pathological Parameters and Parenteral Nutrition of ICU Patients Under Supervision of Dietitians and Surgeons

Background: Nutrient imbalance can frequently occur in patients with indications for parenteral nutrition (PN) after gastrointestinal surgery. This study aimed to compare the recommendations of a surgeon to those of a dietitian in the field of parenteral nutrition.Methods: This study was performed on 256 patients undergoing gastrointestinal surgery who received PN, which included 120 patients who received PN based on recommendations of the surgeons and 136 patients who were referred to receive PN under the supervision of a dietitian in Razi Hospital in Rasht, Iran. Data on PN and clinical outcomes of the patients were collected.Results: Patients under the supervision of dietitians received higher vitamin B complex and lipids and lower vitamin A and vitamin E than the surgeon-supervised patients (all P < 0.001). In the group receiving PN under the supervision of a surgeon, the level of blood glucose (207 vs. 182, P < 0.01), sodium (138 vs. 136, P = 0.01), potassium (3.97 vs. 3.53, P < 0.01), and white blood cell count (9.83 vs. 9.28, P < 0.01) increased significantly at the end of the PN compared to baseline. In the group receiving PN under the supervision of a dietician, the level of serum Cr (1.23 vs. 1.32, P = 0.04), Mg (2.07 vs. 1.84, P < 0.01), and pH (7.45 vs. 7.5, P = 0.03) significantly improved after receiving parenteral nutrition compared to baseline.Conclusion: The amounts of nutrients recommended for PN by the surgeon and dietitian were different. Implementation of dietitian recommendations in critically ill patients under PN can improve patients' clinical parameters.

​Antioxidant Responses of Ricebean [Vigna umbellata (Thunb.) Ohwi and Ohashi] Seedling under Iso-osmotic Potential of Salinity and Drought Stress

Background: Salinity and drought are the major abiotic stresses and both can cause osmotic imbalances. Drought stress directly results in osmotic stress whereas salinity problem firstly disrupts the water balance and eventually induces ion toxicity which results in cyto-toxicity, metabolic impairment, nutrient imbalance and finally poor crop growth and yield. The co-ordinated up-regulation or constitutive expression of antioxidative system in plants is the main defense in plant against these stresses and thus the present experiment was undertaken to study the antioxidant responses under drought and salinity stress at seedling stage in ricebean (Bidhan 1). Methods: For studying the effect of iso-osmotic potential of salinity and drought stress solutions of NaCl and PEG 6000 with -0.2 MPa (50mM NaCl and 10% PEG), -0.4 MPa (100 mM NaCl and 12% PEG) and -0.8 MPa (200mM NaCl and 18% PEG) osmotic potential were used. The experiment was done in the laboratory of Department Plant Physiology, Bidhan Chandra Krishi Viswavidyalaya (BCKV), Mohanpur, Nadia and West Bengal in the year 2017-18 and 2018-19. Result: Under moderate to high intensity of osmotic stresses the leaf proline content decreased. The mild and medium stress treatments induced much higher activity of GPOX and APX in the leaf which then decreased somewhat as the intensity of stress increased. The experiment showed that drought stress was found to produce more drastic effects on seedling growth in ricebean as compared to the salinity stress at iso-osmotic potentials.

Critical indexes of compositional nutrient diagnosis (CND) and its validation in wheat fields

Plant nutrient composition of can be used as an evaluation criterion for optimum plant growth. The objectives of present study were to (a) derive critical compositional nutrient (CND) norms for survived wheat fields and sufficiency ranges as CND nutrient index for validation samples, (b) provide a squared CND threshold nutrient imbalance index (CND r2) and compare with DRIS nutrient imbalance indices, (c) determine balanced nutrients concentration with CND indices. The yield cutoff value was 4,232 kg.ha-1. The CND indexes results indicate that Zn is the most deficient nutrient in wheat, followed by Cu, Fe, Mn and B, whereas N is the most excessive nutrient, followed by K, Ca, Mg and P. In the validation trials, the yield cutoff value were reported 5.023 kg.ha-1. The calculated CND r2 in the validation population was lower than that of the survey wheat fields, indicating a more balanced concentration of nutrients due to the application of fertilizer treatments. Significant principal component (PC) loadings were obtained after the varimax rotation. The first three PCs in high- and low-yielding subgroups and whole data set indicated 52.8, 54.6 and 48.8 % total variance, respectively. This study revealed that the decline in the wheat yield was due to the nutrient imbalance associated with multi nutrient deficiency (Zn, Cu, Fe, Mn and B) and multi nutrient excess (N, K, Ca, Mg and P).

Nutrient Imbalance of the Host Plant for Larvae of the Pale Grass Blue Butterfly May Mediate the Field Effect of Low-Dose Radiation Exposure in Fukushima: Dose-Dependent Changes in the Sodium Content

The pale grass blue butterfly Zizeeria maha is sensitive to low-dose radioactive pollution from the Fukushima nuclear accident in the field but is also highly tolerant to radioactive cesium (137Cs) in an artificial diet in laboratory experiments. To resolve this field-laboratory paradox, we hypothesize that the butterfly shows vulnerability in the field through biochemical changes in the larval host plant, the creeping wood sorrel Oxalis corniculata, in response to radiation stress. To test this field-effect hypothesis, we examined nutrient contents in the host plant leaves from Tohoku (mostly polluted areas including Fukushima), Niigata, and Kyushu, Japan. Leaves from Tohoku showed significantly lower sodium and lipid contents than those from Niigata. In the Tohoku samples, the sodium content (but not the lipid content) was significantly negatively correlated with the radioactivity concentration of cesium (137Cs) in leaves and with the ground radiation dose. The sodium content was also correlated with other nutrient factors. These results suggest that the sodium imbalance of the plant may be caused by radiation stress and that this nutrient imbalance may be one of the reasons that this monophagous butterfly showed high mortality and morphological abnormalities in the field shortly after the accident in Fukushima.