Diameter of the root neck and number of green stems in alfalfa plants damaged by the larvae of alfalfa longhorn beetle(Plagionotus floralis Pall.: Coleoptera, Cerambycidae)

Evgeniya Zhekova

Abstract: During the period 2010-2015, three field trials with three alfalfa varieties are conducted in the experimental field of the IASS “Obraztsov chiflik” - Rousse: Pleven 6, Prista 3 and Mnogolistna 1 in four replications, perpendicular method with randomization of the plots, in non-irrigating conditions and 12,5 cm distance between rows. The aim of the study is to investigate the correlation between damage caused by alfalfa longhorn beetle larvae, the age of alfalfa plants, the diameter of the root neck and the number of green stems in alfalfa varieties. Two-, three- and four-year-old alfalfa plants are more susceptible to damage by alfalfa longhorn beetle larvae, a prerequisite of which is the larger diameter of the root neck. The largest diameter of the root neck has the damaged four-year old plants. There is no proven difference between number of green stems of healthy plants and plants damaged by alfalfa longhorn beetle larvae, depending on the age and variety of alfalfa. The reason is their considerable quantitative variability under the influence of genetic features, cultivation technology, climatic conditions, etc.

Keywords: alfalfa; alfalfa longhorn beetle; damage; diameter of the root neck; number of green stems

Date published: 2019-05-27