The Effect of Sugarcane Residue Compost on Growth and Grain Yield of Triticale under Drought Stress

Triticale is a commercial cereal with a vast potential to feed human and animal. This plant can be cultivated in poor soils that are not suitable for wheat production. In irrigation cutoff stress conditions, reduces growth and yield and yield components of triticale. One of the most important ways to reduce the negative effect of drought stress on plant is using compost fertilizer in the soil. Using compost fertilizer in agricultural soils lead to increase nutrient elements and conserving the soil water. Generally, compost fertilizer of sugarcane residues, improves moisture storage and physical and chemical conditions of the soil. So that sugarcane residue compost fertilizer contributes to preserving the moisture storage of the soil and to supply the nutrients required by the plant. In this study, the most important aim is to study the effect of sugarcane residue compost fertilizer on triticale yield and yield components under irrigation cutoff stress condition in Mollasani region, Ahwaz, Kuzestan province.

In order to investigate the effect of sugarcane residue compost fertilizer on growth, yield and yield components of triticale under drought stress conditions, a field experiment using a split-plot arrangement accomplished in a randomized complete block design with four replicates in the research farm of Agricultural Sciences and Natural Resources University of Khuzestan (in 31º N, 48º E, 35 Km north-east of Ahwaz, and 20 m above the sea level) during 2018-2019 growing season. Experimental factors include four levels of drought stress (complete irrigation, irrigation cutoff from spike emergence to physiological maturity, irrigation cutoff from pollination stage to physiological maturity and irrigation cutoff from milky-dough stage to physiological maturity) as a main factor in main plots and five amounts of sugarcane residues compost (0, 10, 20, 30 and 40 t ha-1) as a sub factor in sub-plots.

Analysis of variance showed that the effect of drought stress, sugarcane residue compost and their interaction on the measured traits were significant. Mean comparison showed that the maximum amount of triticale traits was obtained in full irrigation and the lowest amount was observed in drought stress from spike emergence to physiological maturity. Also, with increasing the amount of sugarcane residue compost, the amount of traits increased and reached a maximum at the level of 40 t ha-1. Mean comparison of grain yield under the interaction of drought stress and sugarcane residue compost showed that the highest grain yield (4288 kg ha-1) was under full irrigation and 40 t.ha-1 of sugarcane residue compost and the lowest grain yield (1134 kg ha-1) was obtained in drought stress from spike emergence to physiological maturity and non-use of sugarcane residue compost. In the conditions of drought stress caused by the interruption of irrigation, the vegetative and reproductive growth of the plant is reduced, which causes a decrease in yield components and ultimately leads to a decrease in seed yield. On the other hand, the use of compost fertilizer reduces the effect of stress by preserving water and providing nutrients needed for plant growth and leads to an increase in seed yield.

Generally, the results showed that drought stress conditions decreased growth, grain yield and yield components of triticale but using sugarcane residues compost fertilizer decreased the negative impact of drought stress conditions on measured traits. Also, in areas with irrigation shortage or lack of rainfall at the beginning of flowering stage, 40 tons per hectare of sugarcane residues compost fertilizer is recommended for maintaining grain yield.