University of Tabriz Journal of Agricultural Science and Sustainable Production 2476-4310 22 4 2013 02 03 Measuring of -1,3 Glucanase Activity in Trichoderma Virens Isolates and Selection of the Best Isolates for Biological Control of Cucumber Root Rot Measuring of -1,3 Glucanase Activity in Trichoderma Virens Isolates and Selection of the Best Isolates for Biological Control of Cucumber Root Rot 149 161 839 FA Fatemeh Zavvari Nazazollah Sahebani Hasan Reza Etebarian Journal Article 2014 02 26 In this study four isolates of  <em>Trichoderma</em> <em>virens</em> (<em>T.virens</em> 414, <em>T.vir</em>ens 414.8, <em>T.virens</em> 304 and  <em>T.virens</em> 404.4) were compared based on extra cellular β-1,3 glucanase production and biological control of root rot cucumber (<em>Phytophthora</em> <em>drerchsleri</em>) in laboratory and green house experiments.The <em>in vitro </em>potential of those isolates were evaluated against  <em>P.drechsleri</em>  through production of volatile and dual culture. The pH (3, 5, 7, 8, 9) and temperature effects(5, 15, 20, 25, 30, 40˚C) on <em>Trichoderma </em>mycelial growth were also evaluated. Colony growth rate of thease isolates were also studied in water agar culture medium containing carboxy methyle cellulose (CMC) and showed direct correlation with β-1,3 glucanase secretion. According to results <em>T. virens</em> 304 and <em>T. virens </em>414.8  were the best isolates in biocontrol of <em>. drechsleri</em>. Result also showed direct correlation between β-1,3 glucanase secretion and inhibition growth of <em>phytophthora</em>  mycelium and reduction of <em>phytophthora</em> infection. In this study four isolates of  <em>Trichoderma</em> <em>virens</em> (<em>T.virens</em> 414, <em>T.vir</em>ens 414.8, <em>T.virens</em> 304 and  <em>T.virens</em> 404.4) were compared based on extra cellular β-1,3 glucanase production and biological control of root rot cucumber (<em>Phytophthora</em> <em>drerchsleri</em>) in laboratory and green house experiments.The <em>in vitro </em>potential of those isolates were evaluated against  <em>P.drechsleri</em>  through production of volatile and dual culture. The pH (3, 5, 7, 8, 9) and temperature effects(5, 15, 20, 25, 30, 40˚C) on <em>Trichoderma </em>mycelial growth were also evaluated. Colony growth rate of thease isolates were also studied in water agar culture medium containing carboxy methyle cellulose (CMC) and showed direct correlation with β-1,3 glucanase secretion. According to results <em>T. virens</em> 304 and <em>T. virens </em>414.8  were the best isolates in biocontrol of <em>. drechsleri</em>. Result also showed direct correlation between β-1,3 glucanase secretion and inhibition growth of <em>phytophthora</em>  mycelium and reduction of <em>phytophthora</em> infection. https://sustainagriculture.tabrizu.ac.ir/article_839_6bd69870e54247fc29edf460dfb85281.pdf