Yields of Tomato Phenotypes Modified by Planting Density, Mulch, and Row Covers

Abstract

Abstract Bare ground (BG), black polyethylene mulch (ML), and polyester row covers with mulch (MRC), combined with three planting densities, provided increasing levels of cropping intensity to study phenotypic response. Four tomato (Lycopersicon esculentum Mill) phenotypes, ‘Sub Arctic Maxi’ (SAM), ‘New Yorker’ (NY), UNH-328 (328), and ‘Westover’ (WVR) represented combinations of small and large plant size and early and late maturity. Early and total yield responses to planting density were linear whether in ML, MRC, or BG treatments, and each phenotype also showed predominantly linear yield increases with increasing density. These linear increases were enhanced in SAM by ML and MRC, but the same mulch and row cover treatments tended to reduce the density response in other phenotypes. The difference was believed to relate to flowering pattern and time relative to vegetative development. Within MRC, compact plants were the most responsive to density in total, but not in early, yield. The predominant effect of ML and MRC was to improve earliness, with each treatment contributing an increment increase in early yield. However, the performance of one phenotype (328) was unchanged by ML or MRC, perhaps reflecting inherent stability.