Ahmad Shams Aldien Shaaban*⁽¹⁾ Abdullah Al-Yousef⁽²⁾ and Ahmad Haj Suliman⁽²⁾

(1). Department of Processing Data and Statistical Analysis, Center for Strategic Studies and Research, University of Aleppo. Aleppo, Syria.

(2). Aleppo Research Center, General Community for Scientific Agriculture Research (GCSAR), Damascus, Syria.

(*Corresponding other: Dr. Ahmad Shams Aldien Shaaban. E-mail: Shaabany57@gmail.com).

Received: 21/09/2016                                 Accepted: 27/10/2016

Abstract

This study was conducted to predict evapo-transpiration and rainfed wheat production in Aleppo province, Syria, using PGSGC (Plant Growes Small Grain Crops) simulation model under different scenarios, which contains different zones: Zone A (Yhmoul), zone B (Zerbeh) and zone C (Sfireh), and three sowing dates: early (first half of Nov.), medium (second half of Nov.), and late (the first half of Dec.), and two different wheat genotypes, one was early, while the other was late in maturity. The simulation was conducted during 1998-2015 using daily minimum and maximum temperatures, solar radiation, and rainfall. The simulation outputs showed a clear variation in the curves of the development of cumulative evaporation, cumulative transpiration, and dry matter accumulation (biological, and grain yield). The beginning of water stress was determined in days, besides the period which had a low fraction of transpirable water (FTSW). The evapo-traspiration varied between 207.9-220.9 mm at Sfireh, whereas, they ranged between 231.1-248.9 mm at Zerbeh, and ranged between 279.4-296.1 mm at Yahmoul. Evaporarted water was determined as ratio of total rainfed quantities varied according to different scenarios. The estimated values ranged between 57-64% at Sfireh, 52-58% at Zirbeh, and 41-49% at Yahmoul. The Grain yield decreased when using early maturity genotype at early sowing date by 395, 393, and 538 kg/ha when sown at the medium date. Also, the grain yield decreased by 640, 656, and 927 kg/ha when sowing date delayed to late date at Sfireh, Zerbeh, and Yhmoul, respectively. The lowest loss in grain yield achieved (19%) by delaying sowing date, and using late maturity genotype at Yhmoul. This loss accounted about 48 kg/ha when delaying sowing date from early date to medium date. This loss accounted about 17.12 thousand tons for the cultivated areas of rainfed wheat at Izaz (Yhmoul) region during 2014/2015 season.

Key Words: Simulation Model PGSGC, Evapo-transpiration, Sowing dates, Stability zones, Rainfed wheat genotypes.

Full paper in Arabic: PDF