Distribution of threshold values of harmfulness of larvae of lamellar phytophages in time

Goal. Clarification of the threshold of harmful larvae for 2-year-old pine seedlings at different stages of the growing season. Methods. Phenological observation of the complex of plates of the phylogenetic phytophages: eastern and western, marble, red and shaggy worms. Methods of compilation of...

Full description

Saved in:
Bibliographic Details
Main Authors: E. Korenchuk, V. Drozda
Format: Article
Language:English
Published: Institute of Plant Protection of the National Academy of Agrarian Sciences of Ukraine 2019-05-01
Series:Карантин і захист рослин
Subjects:
Online Access:https://kr.ipp.gov.ua/index.php/journal/article/view/70
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850221106714116096
author E. Korenchuk
V. Drozda
author_facet E. Korenchuk
V. Drozda
author_sort E. Korenchuk
collection DOAJ
description Goal. Clarification of the threshold of harmful larvae for 2-year-old pine seedlings at different stages of the growing season. Methods. Phenological observation of the complex of plates of the phylogenetic phytophages: eastern and western, marble, red and shaggy worms. Methods of compilation of phenological maps and graphic modeling of harmfulness thresholds of phytophages. Results It has been established that the period of harmfulness for larvae of the plates of the breeding phytophages, depending on their phenology, during the vegetation is expediently divided into three stages: A (spring), B (mostly summer), C (autumn), which correspond to different models of thresholds of harmfulness. In particular, the model for the autumn period takes into account the increased likelihood of plant death due to the suppression of larvae of the crust in the spring and summer period and the effectiveness of the measures implemented to regulate their numbers. The system for regulating the number of phytophages should be aimed at maximal protection of the pine culture in period A — prevention of damaging the root system of larvae (chemical insecticide) and preventive saturation of the ecosystem with biological agents in such a way that their maximum efficiency is at period B. Conclusions. For the spring, mainly summer and autumn periods, it is expedient to use different models of hazard thresholds: for the spring and summer x = (0.96y + 0.63) / 3, and for the autumn x = ((0.96y + 0.63) / 3) × 0.577, where — x — ratio of the biomass of the root system to the biomass of the larvae; y — biomass of the root system. The hazard threshold model for the autumn period takes into account the increase in the likelihood of plant death due to the weakening of the crustal larvae in previous periods (spring, summer) and the effectiveness of the measures taken to regulate the number of these phytophages.
format Article
id doaj-art-9c74eeafc6b24b9294cb0621a2f4555f
institution OA Journals
issn 2312-0614
2786-4979
language English
publishDate 2019-05-01
publisher Institute of Plant Protection of the National Academy of Agrarian Sciences of Ukraine
record_format Article
series Карантин і захист рослин
spelling doaj-art-9c74eeafc6b24b9294cb0621a2f4555f2025-08-20T02:06:48ZengInstitute of Plant Protection of the National Academy of Agrarian Sciences of UkraineКарантин і захист рослин2312-06142786-49792019-05-015-6161910.36495/2312-0614.2019.5-6.16-1970Distribution of threshold values of harmfulness of larvae of lamellar phytophages in timeE. Korenchuk0V. Drozda1National University of Life and Environmental Sciences of Ukraine, 15, Heroiv Oborony Str, Kyiv, Ukraine, 03041National University of Life and Environmental Sciences of Ukraine, 15, Heroiv Oborony Str, Kyiv, Ukraine, 03041Goal. Clarification of the threshold of harmful larvae for 2-year-old pine seedlings at different stages of the growing season. Methods. Phenological observation of the complex of plates of the phylogenetic phytophages: eastern and western, marble, red and shaggy worms. Methods of compilation of phenological maps and graphic modeling of harmfulness thresholds of phytophages. Results It has been established that the period of harmfulness for larvae of the plates of the breeding phytophages, depending on their phenology, during the vegetation is expediently divided into three stages: A (spring), B (mostly summer), C (autumn), which correspond to different models of thresholds of harmfulness. In particular, the model for the autumn period takes into account the increased likelihood of plant death due to the suppression of larvae of the crust in the spring and summer period and the effectiveness of the measures implemented to regulate their numbers. The system for regulating the number of phytophages should be aimed at maximal protection of the pine culture in period A — prevention of damaging the root system of larvae (chemical insecticide) and preventive saturation of the ecosystem with biological agents in such a way that their maximum efficiency is at period B. Conclusions. For the spring, mainly summer and autumn periods, it is expedient to use different models of hazard thresholds: for the spring and summer x = (0.96y + 0.63) / 3, and for the autumn x = ((0.96y + 0.63) / 3) × 0.577, where — x — ratio of the biomass of the root system to the biomass of the larvae; y — biomass of the root system. The hazard threshold model for the autumn period takes into account the increase in the likelihood of plant death due to the weakening of the crustal larvae in previous periods (spring, summer) and the effectiveness of the measures taken to regulate the number of these phytophages.https://kr.ipp.gov.ua/index.php/journal/article/view/70thresholds of harm, crunchy phenology, pine common, root system, vegetation period, biomass
spellingShingle E. Korenchuk
V. Drozda
Distribution of threshold values of harmfulness of larvae of lamellar phytophages in time
Карантин і захист рослин
thresholds of harm, crunchy phenology, pine common, root system, vegetation period, biomass
title Distribution of threshold values of harmfulness of larvae of lamellar phytophages in time
title_full Distribution of threshold values of harmfulness of larvae of lamellar phytophages in time
title_fullStr Distribution of threshold values of harmfulness of larvae of lamellar phytophages in time
title_full_unstemmed Distribution of threshold values of harmfulness of larvae of lamellar phytophages in time
title_short Distribution of threshold values of harmfulness of larvae of lamellar phytophages in time
title_sort distribution of threshold values of harmfulness of larvae of lamellar phytophages in time
topic thresholds of harm, crunchy phenology, pine common, root system, vegetation period, biomass
url https://kr.ipp.gov.ua/index.php/journal/article/view/70
work_keys_str_mv AT ekorenchuk distributionofthresholdvaluesofharmfulnessoflarvaeoflamellarphytophagesintime
AT vdrozda distributionofthresholdvaluesofharmfulnessoflarvaeoflamellarphytophagesintime