Preliminary Study On Root Lesion Nematode To Wheat

Root Lesion Nematode of wheat had been known as the important disease in abroad,it causes serious economic losses to wheat production.Diseases of Root Lesion Nematode occured in other crops had been reported in domestic,the damage of Root Lesion Nematode also had been found in experimental plot of Henan agricultural university,it was significant to study this disease on production of food security.This article studied the species of Root Lesion Nematode of wheat,the relationship of the numbers of nematodes per gram of fresh root tissue and the yield at different growth time of wheat,The resistance of 30 cultivars of wheat which were popularized widely and bred recently to Root Lesion Nematode in the field,The central research contents and results as follows:According to morphological measure value and description of Root Lesion Nematode of wheat's species founded in experimental plot of Henan agricultural university,and search the Key to Species of Pratylenchus,with compared to morphological measure value of Prarylenchus hexincisus recorded in literatures,the results showed that the pathogeny of Root Lesion Nematode of wheat was the Prarylenchus hexincisus.The resistance of 30 cultivars(lines) of wheat which were popularized widely and bred recently in Henan to RLN were identified and evaluated in the field.The results indicated that the resistance of wheat cultivars is obviously different,but the holistic resistance of 30 cultivars is rather poor.There are not immune and high resistant cultivars.The resistance of Zhoumai 12,Zhoumai 19 and Zhengmai 9023 to RLN was high,the numbers of nematodes per gram of fresh root tissue was not more than 100 nematodes/g fresh root tissue at different growth time of wheat.The resistance of Yumai 47 and Yumai25 was lower,especially numbers of nematodes per gram of fresh root tissue of Yumai 25 and Yumai 47 was near 2000 nematodes/g fresh root tissue in filling stage.Numbers of RLN in root tissue of Yumai70,Zhengmai 004, Xinmai208,Fumai 936,Yumai 49-198 were diminishingly during whole growth period of wheat,these five cultivars were easily infected by nematodes,but it was difficult to reproduce.Numbers of nematodes per gram of fresh root tissue of Wenmai 19 and Yumai 70-36 was in a high level during whole growth period of wheat.The results of yield loss for RLN disease showed that the yield loss of BW6 was 13.58%,the yield loss of BW9 was 15.46%,which were without nematocide treatments.Through analyzing the correlation between numbers of nematodes per gram of fresh root tissue during different stages and finally yield,the results showed that there was a significant negative correlation between them.The correlation was highest in filling stage,the correlation coefficient was -0.902,which was a highly significant correlation.There was also a highly significant correlation in heading and flowering stage,the correlation coefficient was -0.877,which was a highly significant correlation.The correlation coefficient in turning green stage and jointing stage was -0.609.