Early tree growth and crop yields under and Prosopis cinerariaAilanthus excelsa based agroforestry system in north western India

A field experiment was initiated in 2017 to evaluate the effect of tree species and tree spacing on intercrop productivity and tree growth with advancing age of and in an agroforestry Prosopis cinerariaAilanthus excelsasystem at Bikaner, Rajasthan. Both and were planted at three spacings: 4m × 4m, 6m × P. cinerariaA. excelsa6m and 8m × 8m; and L. Taub. (Cluster bean) was grown as intercrop during the Cyamopsis tetragonolobakharifA. excelsa seasons of 2018 and 2023. At 24 months after planting (MAP), trees were significantly taller and thicker in wider spacings of 6m × 6m and 8m × 8m compared to closer spacing of 4m × 4m; while in P. cineraria, different spacings did not significantly affect tree height and collar diameter. In this period, collar diameter and height of increased by 10.9 and 6.9-fold in 6m × 6m and 9.9 and 6.8-fold in 8m × 8m A. excelsaspacing, respectively. Percent increment in tree growth parameters were higher during initial growth period (6-12 MAP), and decreased in the subsequent months for both . Among the different A. excelsa and P. cinerariaspacings, higher percent increment in collar diameter in both the species at 24 MAP was recorded in 6m × 6m spacing. The intercrop yield in both the years was not significantly affected by different tree species and spacings. The study indicated that could be established and grown faster in arid region at wider A. excelsaspacings to get maximum tree growth