Selective recording and stimulation of individual identified neurons in freely behaving Aplysia

A neuroethological technique is described for selective recording and stimulation of an individual neuron in freely behaving Aplysia by means of a fine wire glued into the connective tissue sheath above the identified cell body. A whole-nerve cuff electrode simultaneously monitored functionally related multiunit axon activity. For biophysical analysis the soma was impaled with a microelectrode when the ganglion was subsequently exposed. The technique is illustrated for several identified neurons involved in different behaviors.     

Direct prediction of site-specific lime requirement of arable fields using the base neutralizing capacity and a multi-sensor platform for on-the-go soil mapping

Precision Agriculture - Liming agricultural fields is necessary for counteracting soil acidity and is one of the oldest operations in soil fertility management. However, the best management...     

Accumulation patterns and health risk assessment of potentially toxic elements in the topsoil of two sloping vineyards (Tokaj-Hegyalja,Hungary)

Journal of Soils and Sediments - In agricultural soils, accumulation and bioavailability patterns of potentially toxic elements (PTEs) are key ecological and health risk issues, especially in...     

Incidence of grapevine trunk diseases is influenced by soil,topology and vineyard age,but not by <Emphasis Type="Italic">Diplodia seriata</Emphasis> infection rate in the Tokaj Wine Region,Hungary

Grapevine Trunk Diseases (GTD) are of great importance worldwide, including Hungary, a Center European country with long wine producing history. Several GTD pathogens have been described till now in Europe, but only a few from Hungary. The presence of a GTD pathogen in the vine does not necessarily result in the immediate appearance of disease symptoms, and information on the importance of environmental factors related to disease incidence are still limited. The aim of this research was to assess the occurrence of GTD in the Tokaj Wine Region, and to determine the biotic and abiotic factors influencing disease incidence. Five vineyards within 15 km radius – each with different topology, soil types, varieties and age – were studied for three consecutive years (2013 – 2015). The incidence of GTD-infection was determined every year for each vineyard. Diplodia seriata was isolated with incidence ranging from 50 to 100%, while Diaporthe spp. were the only other – minor – GTD pathogen found. Topology and soil type appeared to be major abiotic factors affecting incidence of GTD symptom. Disease incidence was also positively correlating with the age of the vineyards, and it was in fact found to be the definitive biotic factor regarding incidence. In contrast, D. seriata infection rate appeared unrelated to disease incidence or to any of the biotic or abiotic factors investigated.     

Frost tolerance,regeneration capacity after frost exposure and high photosystem II efficiency during winter and early spring support high winter survival in Juncus spp.

During the past two decades, significant spread of the perennial weeds Juncus effusus (soft rush) and Juncus conglomeratus (compact rush) in coastal parts of Norway seems to have coincided with an observed rise in winter temperatures. This study investigated the frost tolerance (LT₅₀) and effects of moderate frost exposure on rush plant regrowth over time during the period late November to late winter/spring, and photosynthetic activity in late winter/spring. Juncus effusus and J. conglomeratus of physiologically young age (seedlings) displayed similar high frost tolerance (LT₅₀) and did not differ significantly in regenerative ability following prolonged frost exposure. Regrowth capacity generally increased during winter and when stress conditions increased, shoot formation was prioritised over total biomass production. Maximum quantum efficiency of photosystem II (F_v/F_m) and performance index of photosystem II (PI) were high in late winter/spring, with J. effusus showing higher values than J. conglomeratus. Green, photosynthetically active shoots, which facilitate accumulation of carbohydrates during autumn and even in winter, may provide Juncus spp. with substantial competitiveness in late winter and spring. The results revealed that the dominance of J. effusus over J. conglomeratus in pastures and leys is not due to major differences in winter survival parameters, but probably the higher photosynthetic efficiency observed in J. effusus. Generally higher temperatures during winter and lower frost kill may be contributing to the current increase in rush infestation.