Optimizing water and nitrogen application for neglected horticultural species in tropical sub-humid climate areas: a case of African eggplant (Solanum aethiopicum L.)

African eggplant, a traditional and important nutrient-dense crop to Tanzania’s nutrition and food security. However, yields remain low as a result of sub-optimal irrigation and fertilizer practices. To reduce the yield gap, a randomized split-plot design set up with irrigation as a main and nitrogen (N) treatments as a sub-factor. The irrigation regimes were 100 % (I100), 80 % (I80) and 60 % (I60) of crop water requirements whilst nitrogen levels were 250 kg N/ha (F100), 187 kg N/ha (F75), 125 kg N/ha (F50) and 0 kgN/ha (F0). The study evaluated the effect of irrigation water and N on crop growth variables and yield, fruit quality, WUE and NUE. The study showed the importance of combining different irrigation performance indicators which responds to different levels of water and nitrogen to evaluate and assess suitable irrigation and fertilizer strategies for African eggplant. The crop growth variables (plant height and LAI) had a good correlation with fruit yield (R2 = 0.6 and 0.8). The fruit quality was best performed by 100 % water in combination with 75 % N treatment. The best WUE and NUE was attained at 80 % and 100 % levels of water in combination with 75 % N. However, minimizing trade-offs between the various indicators, the optimal application for African eggplant would likely be around 80 % of the total irrigation requirement and 75 % of the N requirement in sandy clay loam soils under tropical sub-humid conditions.

Bibliographic Details

Main Authors:	Mwinuka, P.R., Mbilinyi, B.P., Mbungu, W.B., Mourice, S.K., Mahoo, H.F., Schmitter, Petra S.
Format:	Journal Article biblioteca
Language:	English
Published:	Elsevier 2021-01
Subjects:	water use efficiency, nitrogen fertilizers, fertilizer application, fruit vegetables, eggplants, horticulture, solanum aethiopicum, crop water use, water requirements, drip irrigation, crop growth stage, crop yield, performance indexes, subhumid climate, soil chemicophysical properties,
Online Access:	https://hdl.handle.net/10568/109854 https://doi.org/10.1016/j.scienta.2020.109756
Tags:	Add Tag No Tags, Be the first to tag this record!