Application of Different Rates and Frequencies of Rejuvenator for the Treatments of Brown Bast Syndrome on Hevea brasiliensis

Background: Brown bast is one of the most serious threats to natural rubber production. It is estimated that brown bast leads to an approximately 15-20% decrease in latex yield production. There is currently no effective method to control this problem and an effort to overcome this problem is in progress by the natural rubber producing countries. Methods: This study evaluated the effect and the most suitable rate and frequency of Rejuvenator application to cure brown bast (latex dryness) and improve latex yield. The Rejuvenator treatment was applied to the selected tree with two different treatment frequencies (every 3 days and every 6 days) and three different Rejuvenator concentrations (5 g/L, 10 g/L and 5 g/L). The Rejuvenator was applied 5 times. Data on latex yield and brown bast cure were then recorded 1 month after the application of the last treatment. The treatments used were T1: No Rejuvenator, T2: 5 g/L of Rejuvenator, T3: 10 g/L of Rejuvenator, T4: 15 g/L of Rejuvenator. Result: Of all the treatment used, T3 (10 g/L) resulted in higher production of latex yield and Hevea bark nutrient concentration (g/t/t) than control. It also gave the highest nutrient content in the bark tissue. The findings of this study reveal that the optimum concentration and frequency of Rejuvenator application were established at 10 g/L every 6 days. More so, the findings explain that inadequate nutrients can be attributed to the brown bast syndrome in rubber plantation which can be prevented with the use of a rejuvenator to the tree’s bark.

Effects of Different Nutritional Conditions on the Growth and Reproduction of Nilaparvata lugens (Stål)

Growth and reproduction are the two most basic life processes of organisms and the distribution of energy in these processes is a core issue of the life history of organisms. Nilaparvata lugens (Stål), the brown planthopper (BPH), is a single-feeding rice pest. In the present study, this species was used as a model for testing the effects of nutritional conditions on various growth and reproduction indicators. First, the third-instar nymphs were fed with three different concentrations (100, 50, and 25%) of artificial diet until the second day of adulthood. The results showed that as the nutrient concentration decreased, the body development and oviposition of BPH were hindered. The total lipid content in the fat bodies was also significantly reduced. RT-PCR analysis showed compared to the 100% concentration group, the expression levels of vitellogenin (Vg) genes in the fifth-instar nymphs, adults, and in different tissues (ovary, fat body, and other tissues) were significantly decreased in the 50 and 25% treatment groups. Western blot analysis showed that Vg protein expression was highest in the 100% group, followed by the 50% group, with no expression in the 25% group. These results indicate that growth and reproduction in the BPH are regulated by, or correlated with, nutrient concentration. This study is of great significance as it reveals the adaptive strategies of the BPH to nutritional deficiencies and it also provides valuable information for the comprehensive control of this pest.

Effect of Organic Fertilizer Form and Dosage on Soil Chemical Properties, Leaf Macro Nutrient Content and Vegetative Growth of Siamese Orange (Citrus nobilis Lour) seedlings

Orange is a national superior commodity that has an important role in increasing foreign exchange for the country. However, the development of citrus cultivation in Indonesia is still relatively low, probably due to soil fertility degradation. Therefore, this study aimed to analyze the effect of differences in the application of organic fertilizer (form and dose) and their interaction on soil chemical properties, nutrient concentration in the leaf (i.e. N, P, K), and growth in Siamese citrus seedlings. The treatments included the application of a combination of forms and doses of organic fertilizer, namely SD1 (powder dose 2 t ha-1), SD2 (powder dose 4 t ha-1), SD3 (powder dose 6 t ha-1), SD4 (powder dose 8 t ha-1), SD5 (powder dose 10 t/ha), GD1 (granule dose 2 t ha-1), GD2 (granule dose 4 t ha-1), GD3 (granule dose 6 t/ha), GD4 (granule dose 8 t ha-1) and GD5 (granule dose 10 t ha-1). The results showed that there was a significant difference in the interaction between form and dose of organic fertilizer only in the number of primary branches at 4 WAP (weeks after application) with the highest values was found in powder organic fertilizer at a dose of 8 t ha-1 and granules organic fertilizer at a dose 10 t ha-1. In addition, the application of powder organic fertilizer application had a higher plant height at 10-12 WAP as compared to the application of granule organic fertilizer.

Interactive Effects of Organic Fertilizers and Drought Stress on Growth and Nutrient Content of Brassica juncea at Vegetative Stage

With the ongoing climate change scenario and alarmingly increased land degradation, understanding complex interactions of drought stress and organic fertilizers on morpho-physiological traits and dynamics of nutrient concentration is pivotal for sustainable production leafy vegetables such as mustard (Brassica juncea). Thus, this study evaluated the effect of drought stress and organic fertilizers on B. juncea growth, physiology, and dynamics of nutrient concentration at the vegetative stage. The plants were exposed to three water stress levels (well-watered (100% field capacity, FC), mild (50% FC), and severe (25% FC) supplemented with three organic fertilizers (chitosan, ultra green, and home-grown natural vegetable foods) either individually or in combination during the vegetative growth stage. Water stress had a negative effect on growth and physiological traits, and macro- and micronutrients of mustard. However, the ameliorative effects of fertilizer application were revealed by improved plant height, leaf area, relative water content, membrane stability index, and chlorophyll content from 9.7% to 26.9%, 28% to 32.72%, 7.97% to 39.51%, 7.93% to 39.66%, and 29.68% to 56.53%, respectively. Analysis of variance revealed a significant effect of soil moisture level, fertilizer type and their interaction on content of macronutrients (Ca, K, P, N, C, S, Na, Mg) and micronutrients (Fe, Zn) in mustard leaves. However, there was no significant effect detected for Cu across all factors as well the interaction effect on Mn. Overall, our results indicated that application of organic fertilizers enables mustard plant to withstand the deleterious effect of drought stress, resulting in improved growth and physiological traits as well as leaf nutrient content.

Influence of Nutrient Concentration on Growth, Yield And Quality of Spinach (Spinacia oleracea L.) in Hydroponic System

The present experiment entitled “Influence of nutrient concentration on Growth, Yield and Quality of Spinach (Spinacia oleracea L.) in Hydroponic system” was carried out in Shade net, Research Field, Department of Horticulture, SHUATS, Prayagraj during March- April,2020.. The experiment was laid out in complete randomized design (CRD), with eight treatments, replicated thrice with nutrient field technique hydroponics system and variety Mulayam of Spinach, the treatments were T1 (NPK 6.25 ml/plant), T2 (NPK 8.33 ml/plant), T3 (NPK 10.41 ml/plant), T4 (NPK 12.5 ml/plant), T5 (NPK 14.58 ml/plant), T6 (NPK 16.66 ml/plant), T7 (NPK 18.75 ml/plant) and T0 (NPK 0 ml/plant). From the present experimental findings, it is found that structure with treatment T4 was found best in terms of Growth and yield parameters of spinach in NFT hydroponic system followed by structure with T3 and T1 due to appropriate supply of plant nutrients and the water treated plants had the lowest values. Maximum gross return (1871.30Rs) and net return (746.30 Rs) and maximum benefit cost ratio (1.66) was also observed in treatment T4. As seen from the experiment, it was observed that the treatment T4 was ideal nutrient for Spinach good growth and yield. Therefore, an ideal nutrient concentration helps the plants in good growth and yield.

The Pour-Through Procedure for Monitoring Container Substrate Chemical Properties: A Review

The pour-through procedure is a nondestructive method commonly used by horticultural crop producers and research scientists to measure chemical properties and nutrient availability in container substrates. It is a method that uses water as a displacement solution to push the substrate solution out of the bottom of the container so it can be analyzed for pH, electrical conductivity, and nutrient concentrations. The method was first introduced in the early 1980s. Since then, research has been conducted to determine factors that affect the results of the pour-through including volume, nature and timing of application of the displacement solution, container size, and substrate stratification. It has also been validated against other common methods for determining container substrate pH, EC, and nutrient concentration, most notably the saturated media extraction procedure. Over the past 40 years, the method has been proven to be simple, robust, and consistent in providing crop producers and researchers valuable information on substrate chemical properties from which management decisions and experimental inferences can be made.

Serratia plymuthica MBSA-MJ1 Increases Shoot Growth and Tissue Nutrient Concentration in Containerized Ornamentals Grown Under Low-Nutrient Conditions

High fertilizer rates are often applied to horticulture crop production systems to produce high quality crops with minimal time in production. Much of the nutrients applied in fertilizers are not taken up by the plant and are leached out of the containers during regular irrigation. The application of plant growth promoting rhizobacteria (PGPR) can increase the availability and uptake of essential nutrients by plants, thereby reducing nutrient leaching and environmental contamination. Identification of PGPR can contribute to the formulation of biostimulant products for use in commercial greenhouse production. Here, we have identified Serratia plymuthica MBSA-MJ1 as a PGPR that can promote the growth of containerized horticulture crops grown with low fertilizer inputs. MBSA-MJ1 was applied weekly as a media drench to Petunia×hybrida (petunia), Impatiens walleriana (impatiens), and Viola×wittrockiana (pansy). Plant growth, quality, and tissue nutrient concentration were evaluated 8weeks after transplant. Application of MBSA-MJ1 increased the shoot biomass of all three species and increased the flower number of impatiens. Bacteria application also increased the concentration of certain essential nutrients in the shoots of different plant species. In vitro and genomic characterization identified multiple putative mechanisms that are likely contributing to the strain’s ability to increase the availability and uptake of these nutrients by plants. This work provides insight into the interconnectedness of beneficial PGPR mechanisms and how these bacteria can be utilized as potential biostimulants for sustainable crop production with reduced chemical fertilizer inputs.

Symptoms and interrelationships of macro and micronutrients available for soybean

Nutrients have differences in their functions as metabolic and structural constituents in plant organs. The specific identification of the symptoms of excess or deficiency of nutrients is essential for the correct management to be carried out in order to avoid production losses. In this context, this research aimed to evaluate the symptoms of deficiency and excess of nutrients in soybean. The experiment was carried out on a bench, with 3-liter containers, in which uniformly germinated seedlings were selected for implantation. Initially, the seedlings were subjected to a complete nutrient solution to allow for a uniform and unrestricted initial development over a period of one week. Then, the plants were subjected to solutions with twice as much nutrient, absence of nutrients, complete solution and nutrient restriction, individual omissions resulted in morphological changes, which translated into visual symptoms characteristic of the nutritional deficiency of the respective nutrient. The solution with twice the nutrient concentration of the complete solution showed an increase in the absorption of N, Mg, K and Fe, for Cu it was twice the absorption and for Zn five times more. There was a decrease in the absorption of Ca and Mn and, with that, it is concluded that the availability of twice as many nutrients did not result in double their absorption.

Facet-selective morphology-controlled remote epitaxy of ZnO microcrystals via wet chemical synthesis

We report on morphology-controlled remote epitaxy via hydrothermal growth of ZnO micro- and nanostructure crystals on graphene-coated GaN substrate. The morphology control is achieved to grow diverse morphologies of ZnO from nanowire to microdisk by changing additives of wet chemical solution at a fixed nutrient concentration. Although the growth of ZnO is carried out on poly-domain graphene-coated GaN substrate, the direction of hexagonal sidewall facet of ZnO is homogeneous over the whole ZnO-grown area on graphene/GaN because of strong remote epitaxial relation between ZnO and GaN across graphene. Atomic-resolution transmission electron microscopy corroborates the remote epitaxial relation. The non-covalent interface is applied to mechanically lift off the overlayer of ZnO crystals via a thermal release tape. The mechanism of facet-selective morphology control of ZnO is discussed in terms of electrostatic interaction between nutrient solution and facet surface passivated with functional groups derived from the chemical additives.