Gypsum Supplies Calcium to Ultisol Soil and Its Effect on Pineapple Growth, Yield and Fruit Quality in Lower Single Bed under Climate Change Issue

A lower bed single row for pineapple cultivation could protect pineapple from soil erosion in rainy season and during drought, however, disease problem could arise due to water logging. Two experiments using a lower bed single row was done to understand the ability of gypsum providing soil calcium (Ca) available to pineapple plant, resistance to heart rot disease, and give better effect on crop growth and fruit quality of the pineapple in Ultisol soil. In the first trial, four level dosis of gypsum (0, 1.0, 1.5, 2.0 Mg ha-1) and dolomite 2 Mg ha-1 were applied by spreading and incorporated into the soil which have saturated with inoculums of Phytophthora nicotianae. In the second trial, gypsum treatments (0, 1.0, 1.5, 2.0, 2.5 Mg ha-1) were applied in the row between the single row beds as a basic fertilizer. The result showed that P. nicotianae attacked the pineapple plants in all treatments at 6 weeks after planting (WAP), and at 10 WAP, the mortality of dolomite treatment reached 63.8%, significantly different than that for gypsum treatments (3.3-14.3%). In the second experiment, gypsum increased plant weight significantly at 3 until 9 months after planting especially when it was applied 1.5-2.5 Mg ha-1. Fruit texture, total soluble solid (TSS), titratable acidity (TA) were not significant different among the treatment but all meet the standards for grades of canned pineapple. Result showed that soil applied gypsum before planting provides soil calcium and met the plant Ca requirement during a period of early and fast growth step and safe for heart rot disease.

Yellow Sap Contamination on Mangosteen (Garcinia mangostana L.) Fruit in Relation to Soil Calcium Contents and Plant Tissue

Yellow sap contamination (YSC) is one of the mangosteen quality constrain in Indonesia. Calcium is the prominent nutrient that influence the incidence of yellow sap contamination. A research with objective to observe the relationship between incidence YSC and Ca availability in soil as well as plant tissue was done in ten locations in West Sumatra, Lampung and West Java provinces. Purposive random sampling method was used to determine the site locations. The plant and soil samples were collected from 10 sites and ten tree per sites. Correlation analysis was used to measure the relationship between incidence YSC and Ca content in fruit endocarp, mesocarp, peel, soil and leaf. The result showed that there was a variation of incidence YSC in site location with range of 8.7%−54.04%; 4.0−51.6%; and 17.7−78.6% for percentage of YSC in fruit flesh, segmentation and peel, respectively. Ca content in soil, endocarp, mesocarp and leaf were given significantly negative correlation toward incidence YSC in fruit flesh and segmentation. Ca content in leaf part correlates significantly to Ca availability in soil, endocarp and mesocarp. Ca content in leaf in the range of 1.40- 1.70% indicates YSC less than 10%.

A Rhizogenic Biostimulant Effect on Soil Fertility and Roots Growth of Turfgrass

The excessive use of chemical fertilizers can lead to severe environmental damages. In recent decades, the application of biostimulants to improve soil composition and stimulate plant growth has contributed significantly to environmental preservation. In this paper, we studied the effect of a rhizogenic biostimulant, obtained from fulvic acids, probiotics, and prebiotics, on the fertility of two types of soils, sandy and sandy loam soils, in which turfgrass was growing. Soil samples from plots treated with biostimulant and controls (untreated plots) were collected. The analyzed parameters from the soil include organic matter, microbial activity, soil chemical composition, catalase, dehydrogenase, and phosphatase enzyme activities. Moreover, root lengths was examined and compared in turfgrass species. The biostimulant application improved microbial activity, organic matter, and enzymatic activity in both types of soils. The soil calcium, potassium, magnesium, and phosphorus content increased with the biostimulant application, whereas pH and electrical conductivity decreased. The most relevant improvement was a 77% increase of calcium for sandy loam soil and 38% increase in potassium for sandy soil. Biostimulant application led to a significant increase in turf root length. This increase was greater for sandy soil than in sandy loam soil with an increment of 43% and 34% respectively, compared to control.

Have Sustained Acidic Deposition Decreases Led to Increased Calcium Availability in Recovering Watersheds of the Adirondack Region of New York, USA?

Soil calcium depletion has been strongly linked to acidic deposition in eastern North America and recent studies have begun to document the recovery of soils in response to large decreases in acidic deposition. However, increased calcium availability has not yet been seen in the B horizon, where calcium depletion has been most acute, but mineral weathering is critically important for resupplying ecosystem calcium. This study provides new data in seven watersheds in the Adirondack region (New York, USA), where acidic deposition impacts on soils and surface waters have been substantial and recovery remains slow. Initial sampling in 1997–1998 and 2003–2004 was repeated in 2009–2010, 2014, 2016 and 2017. Exchangeable calcium concentrations increased by an average of 43% in the Oe horizon of three watersheds where this horizon was sampled (10.7–15.3 cmolc kg−1). Changes in calcium were not seen in the individual watersheds of the Oa and B horizons, but as a group, a significant increase in calcium was measured in the upper B horizon. Liming of a calcium-depleted watershed also tripled calcium concentration in the upper B horizon in 5 years. However, stream calcium in unlimed watersheds decreased over the study period. Small increases in B-horizon calcium may be underway.

Patterns in steppe meadow vegetation at the border of Forest-steppe and Steppe zones of the Southern Ural

The patterns (mosaicity) in steppe meadow vegetation were characterized at the border of Forest-steppe and Steppe zones of the Southern Ural by hierarchical continuum concept theory for Troitskiy state natural complex preserve example. It has been established that the discordant natural region bring about mosaicity destruction micro-patterns are fuzzy, parcels are not formed and coenotics (12,0 m) level is identified only. The steppe meadow vegetation is characterized by coenotic level continuum coenotic patterns have almost identical dominant and co-dominant species composition, phytochorologic units form combination of four meadow grasses with middle and weak contagious spatial distribution and most species have random spatial distribution. But the steppe meadow biotopes are characterized by specifics of abiotic factors. The significant factors, influencing coenotic patterns and biotopes of steppe meadow, are soil calcium and nitrogen regime, soil aeration, moistening and its variability.

Correction of Potassium Fertigation Rate of Apple Tree (Malus domestica Borkh.) in Central Russia during the Growing Season

The proper use of potassium fertilizer can stimulate a significant yield increase. However, the application of excessively high rates of potassium can reduce the availability of soil calcium for apple trees. The potassium fertigation rate must meet the apple tree’s requirements so that the applied fertilizers can be absorbed by the roots as much as possible. Crop load in apple orchards sometimes varies significantly in different years. The potassium content in apple fruits is relatively high, and the maximum requirement for this nutrient occurs when fruits grow and ripen. Different crop loads at that time mean the various demands of trees and need for changing application rates for this nutrient. The investigation was carried out in the experimental orchard of I.V. Michurin Federal Scientific Centre (Michurinsk, Russia) in 2016 and 2017 (52.885131, 40.465613). We studied seasonal changes of potassium and calcium contents in soil, fruits, and leaves and their relationship with yield during the research. We paid much attention to the potassium rate shift on its content in leaves and fruits and cultivars “Lobo” and “Zhigulevskoye” yield. If the potassium application rate changes according to the actual crop load, it stimulates the yield growth or (if the crop load was relatively low) the reduction of the rate did not lower the productivity. Moreover, we studied the relationship between potassium and calcium nutrition. The decrease in potassium fertigation rate increased the availability of soil calcium. It was the reason for fruit calcium concentration enlargement and mitigation of the K/Ca ratio. We also specified some parameters for soil–leaf diagnosis for potassium nutrition during the growing season.