Ahmed Al-Ali Al-Khalaf (1)*
(1). Raqqa Research Center, General Commission for Scientific Agricultural Research,Syria.
(*Corresponding author: Ahmed Al-Ali Al-Khalaf, E-Mail: dr.ahmadelkhalf@gmail.com,).
Received: 20/12/2021 Accepted: 21/04/2022
Abstract:
The research was carried out at the Agricultural Scientific Research Center in Raqqa during the 2021 agricultural season, to study the effect of planting dates and plant density on some traits of roselle crop. Four planting dates (April 15, April 30, May 15 and May 30) and four plant densities (4, 8, 12 and 16) plants/m2 were used, according to a split plot design with three replications. The following characteristics were studied: plant height (cm), number of leaves/plant, stem diameter (cm), number of fruits/plant, yield of dry sepals (g/plant) and harvest index %. The results showed that there were significant differences for the effect of planting date and plant density on all studied traits at the 5% level, and the interaction between them did not show any significant effect on the studied traits. The planting date of 30th April was superior compare the other studied dates in terms of stem diameter with an average of 2.7 cm, and it produced the largest number of fruits per plant (73.8) with an increase of 2.0 and 8.5 And 17.6% compared to the planting dates of April 15, May 15 and May 30, as well as the superiority in the productivity of dry sepals leaves (36.3) g/plant, with an increase of 7.4, 26.2 and 38.6%, respectively. The plant density of 4 plants/m2 recorded superiority in stem diameter, number of leaves per plant, number of fruits per plant, and harvest index with an average of 3.0 cm, 316.5, 132.1 and 2.1%, respectively. The plant density of 8 plants m2 achieved an increase in the weight of dry sepals 62.1 g/plant and the harvest index 2.0%, while the plant density of 16 plants/ m2 achieved an increase in the average plant height of 183 cm. The study suggests planting roselle on April 30, with a plant density of 8 plants/m2 to obtain the highest weight of dry sepals under the current study conditions.
Keywords: planting date, plant density, roselle.
Full paper in Arabic: pdf