Growth performance and response of three biotic agents in commercially grown eucalyptus clones in agroforestry

Abstract

The present study documents field performance of 21 commercially grown clones (BCM 7, BCM 271, BCM 288, BCM 316, BCM 411, BCM 413, BCM 526, BCM 2023, BCM 2045, BCM 2070, BCM 2135, BCM 2306, BCM 2313, Wimco 12, Wimco 14, Wimco 15, K 23, K 25, EC 4 and unnamed one belonging to different Eucalyptus species including a seedling
population of locally collected Eucalyptus hybrid as control). Clones were evaluated for their growth and susceptibility to three biotic agents viz. Leptocybe invasa causing gall induction, Cylindrocladium quinqueseptatum causing leaf blight and Botryosphaeria spp. causing stem canker. Clones were planted in a randomized block design with five replications and five trees in each replication. Wheat was grown as intercrop in field during first and second winter seasons; however, no intercrop was grown during summer seasons. The results indicate significant variation for height, DBH, clear bole length, crown diameter among the tested clones. Ratings of individual clones for growth index (GI), susceptibility index (SI), and composite growth and susceptibility index (GSI) for gall, leaf blight and stem canker also showed significant variation among clones. GSI indicated that clones Wimco 12, BCM 526 and BCM 316 were superior over other clones. The results also confirm the superiority of clone Wimco 12 of E. grandis over many of the existing commercially grown clones of E. tereticornis and E. camaldulensis.