The phytosanitary form and fighting measures against diseases and pests of sugar beet from Republic of Moldova

Abstract

Sugar beet is one of the most important agricultural crops in the Republic of Moldova. The North and Central regions have good enough pedoclimatic conditions. The genetic potential of sorts and hybrids can be created through the application of modern technologies in order to grow at least 32—35 tons/ha of sugar beet roots. In the Republic of Moldova, sugar beet vegetates between 160 and 180 days in the first year and needs approximately an amount of 2400—2900°C, average of 15.3—15.4°C. Each phenological phase needs different temperatures: at least 4C° is necessary for planting and springing; an amount of 650°C is necessary for foliar apparatus; an amount of 1150— 1800°C is necessary to grow the volume of roots and for sugar depositing the average of 2400 to 2600°C is necessary. The mentioned temperatures ensure a normal development of sugar beet plants. If these temperatures fluctuate, the pathogens and pests are stimulated to develop. The most frequent diseases of sugar beet are: Pythium de baryanum H e s s e., Aphanomyces cochlioides D r e s c h., Peronospora schachtii F u c k., Phoma betae F r. Cercospora beticola S a c c., Erysiphe communis G r e v. f. betae J a c z., virosis — Beta virus 2, 3 ¤i 4 etc. The main pests belong to the following categories: Homoptera: Aphis fabae S c o p. (fam. Aphididae), Pemphigus fuscicornis K o c h. (fam. Pemphigidae); Coleoptera: Agriotes sp. (fam. Elateridae), Chaetocnema concinna M. Ch. breviuscula Fld., Cassida nebulosa L. (fam. Chrysomelidae), Atomaria linearis S t e p. (fam. Cryptophagidae); Bothynoderes punctiventris G e r m., Tanymechus dilaticollis G y l l., T. palliatus F., Psalidium maxillosum F., (Curculionidae); Lepidoptera: Agrotis segetum D e n. et S c h i f f., Authographa gamma L. Mamestra (Barathra) brassicae L. (Noctuidae), Loxostege sticticalis L. (Pyralidae), Gnorimoschema ocellatella B o y d.; Diptera Pegomyia betae C u r t i s. (fam. Anthomyidae). Heterodera schachtii Schmidt (Heteroderidae). The most recommended insecticides for fighting the pests are: Actara 25 WG, Actellic 50 EC, Arrivo 250 CE, Bastar 40 EC, Bi-25 Nou, Decis 2,5 EC, Decis Duplet 36 EC, Decis Forte 120 EC, Diazol 60 CE, Dursban 480 EC, Pirimor 50 WG, Pyrinex 250 ME, Sumithion 50 CE, Sharpei ME, Virin — OS, Zolone 35 EC. The most important fungicides recommended for fighting the diseases are: Derosal 50 SC, Fundazol 50 WP, Impact 25 SC, Oxiclorurº de cupru WP, Privent 25 WP, etc. (D a - n i l o v and colab., 2003; *Prognoz rasprostraneniä…).