Corn (Zea mays L.) production and chlorophyll fluorescence affected by drought stress, N fertilization, and genotype

Abstract

Background

Corn (Zea mays L.) physiology and production in drought stress conditions may be importantly affected by soil N and plant genotype.

Objective

So, more has yet to be indicated on how drought stress and N fertilization may affect production and chlorophyll florescence of corn genotypes as the objective of the present research.

Methods

The experiment was a split plot on the basis of a randomized complete block design (RCBD) with four replicates conducted in two research sites in 2020. Drought stress levels (main plots) including irrigation after 70 mm evaporation from evaporating pan Class A, irrigation stoppage at flowering, grain filling and both flowering and grain filling, N chemical fertilization (sub plots) including control (0), 100, 200, 300 kg ha^-1 and corn genotypes (sub-sub plots) including Kusha 201 (G1), Fajr 260 (G2), and Dehghan 400 (G3) were tested. Different corn morphological (cob diameter, CDM), yield (biological yield, BY, and harvest index, HI) and florescence indices (Fo, Fm, Fv, and Fv/Fm) were determined.

Results

Although drought stress significantly decreased CDM, biological yield, and fluorescence indices, N fertilization (N300) alleviated the stress and G1 had higher BY, and G3 had less CDM (medium) and higher HI and Fo. The significant interaction of drought stress and N fertilization indicates, depending on the level of drought stress, the response of corn genotypes to N fertilization is different.

Conclusion

Depending on stress intensity, determination of appropriate level of N feralization and genotype may result in the most optimum yield production.