Correlation between damage symptoms caused by maize stem borer (Chilo partellus Swinhoe) and maize (Zea mays) yield
Abstract
An investigation was conducted at Udaipur (Rajasthan) during kharif 2008 and 2009 with single cross moderate resistant hybrid (HQPM-1) and composite susceptible variety (African Tall) against Chilo partellus Swinhoe. The different densities of larvae (4, 8, 12, 16, 20, 24, 28 and 32) were released after 12 to 14 days of sowing in plant of HQPM-1 and African Tall to record leaf injury rating (1–9). Correlation between LIR and plant height of HQPM-1 and African Tall showed significant negative correlation being r =-0.981 and-0.988 in HQPM-1 and r =-0.960 and-0.950 in African Tall during 2008 and 2009, respectively, whereas, plant height with tunnel number and tunnel length in HQPM-1 and African Tall showed positive correlation but non significant. The tunnel number and tunnel length showed highly significant positive correlation in HQPM-1 being r = 0.955 and 0.959 and 0.996 and 0.985 in African Tall during 2008 and 2009, respectively. The correlation coefficient between tunnel length and yield was nonsignificant in both varieties during both year of investigation.
Keywords
Chilo partellus Swinhoe, Correlation coefficient, Leaf injury rating (LIR), Tunnel length, Tunnel number