Optimizing Sowing Depth of Tef for Irrigated Mediterranean Conditions: From Laboratory to Field Studies

Abstract

Developing new crops adapted to arid conditions is a promising approach to meet the increasing demand for food production under expanding aridity. Tef [Eragrostis tef (Zucc.) Trotter] is a C4 cereal crop cultivated mainly in Ethiopia and the Horn of Africa, and known for its high resilience to stressful environments. Due to their tiny size, tef seeds are traditionally sown by broadcasting and lightly covering with soil. Under semiarid Mediterranean conditions, a deeper sowing may guarantee seedling establishment while saving on irrigation water. The objective of this study was, therefore, to determine the effects of sowing depth on tef emergence, development, lodging, and productivity. Tef seeds were sown at different depths in test tubes and pots, and in two field experiments. In tubes and pots, time from sowing to emergence increased about twofold and emergence rate decreased in the deepest sowing (3 cm) treatment compared to controls (0 cm). In the pot and field trials, deep sowing (3 cm) significantly reduced plant height, shoot and root biomass, and lodging. Sowing depths of 1–2 cm allowed successful plant establishment while not exacting penalties on plant emergence or development; hence this range appears to be optimal for sowing irrigated tef.

Identification of minor alleles associated with reduced lodging in tef (Eragrostis tef)

“…Lodging is a complicated phenomenon resulting from plant (shoot and root) traits (Berry et al ., 2004), environmental (soil properties and moisture) factors (Pinthus, 1974; Berry et al ., 2000), and management practices (irrigation, sowing depth and density) (Ben-Zeev et al ., 2020 a , b ). The nature of tef lodging as a dynamic and largely irremediable phenomenon is clearly depicted in the LI distributions at 8–10 WAE across the four studied environments (Figs.…”

“…2004), environmental factors (soil properties and moisture) (Pinthus 1974; Berry et al . 2000), and management practices (irrigation, sowing depth and density) (Ben-Zeev, Kerzner, et al . 2020; Ben-Zeev, Rabinovitz, et al .…”

“…Adapting a traditional crop, such as tef, to modern, highly mechanized cultivation requires reevaluation and calibration of agronomic practices in tandem with genomic studies and breeding. The introduction of tef as a new crop to irrigated Mediterranean conditions presents many challenges, at each step of its growth, some of which have been targeted in our recent studies (Ben-Zeev et al ., 2020 a , b ). The relatively minor attention paid to tef in research, as well as the lack of a reference genome and diversity panel, has hindered studies on the genomic basis of key traits in this crop plant (Girija et al ., 2021).…”

“…Adapting a traditional crop, such as tef, to modern, highly mechanized agriculture requires reevaluation and calibration of agronomic practices in tandem with genomic studies and breeding. The introduction of tef as a new crop to irrigated Mediterranean conditions presents many challenges, at each step of its growth, some of which have been targeted in our recent studies (Ben-Zeev, Kerzner, et al . 2020; Ben-Zeev, Rabinovitz, et al .…”

“…Lodging can be divided into stem lodging, in which the stem bends or breaks, and root lodging, in which the angle between the stem and the soil is a changed due to root disanchoring (Berry et al . 2004), the latter being the prime cause of tef lodging(Ben-Zeev, Rabinovitz, et al . 2020).…”