Evaluation of the Growth and Yield Responses of Rice Cultivars to Bed Preparation Methods and Seedling Production Times

IntroductionThe food providing for the growing world population has always been one of the main concerns of mankind and rice is one of the most important sources of human food. The importance of rice plant in human nutrition and the necessity of achieving self-sufficiency in its production through increasing yield is not hidden from anyone. Among the solutions that humans have used to deal with this problem is choosing the right planting method, planting date and cultivars. Currently, the cultivation of this plant is carried out in most parts of the world in the form of transplanting. Supplying sufficient amount of water is necessary to increase crop production and lack of water is one of the basic limitations in the development of rice cultivation in some regions of the world. Therefore, it is an undeniable necessity to choose a suitable bed for planting plants that will reduce water consumption and produce optimal crops. Also, planting date can have a significant impact on crop growth and rice yield, and it is important to determine the most suitable cultivars for a special planting date. Despite the great importance of different rice transplanting beds on its crop production and the optimal management of these beds through the application of appropriate planting dates that can have a significant impact on crop production, so far not many studies have been conducted in Khuzestan.Materials and MethodsThis research was designed to determine the feasibility of establishing rice cultivar seedlings in dry beds and compare it with wet conditions at different times of seedling production. The experiment was carried out during the cropping years of 2021 and 2022 at the Shavur research station in Khuzestan province, located 65 km north of Ahvaz. It was conducted using a split-plot design within a randomized complete block design with three replications. The main factor, planting beds for the seedlings, included transplanting in a conventional bed (paddling), transplanting in a bed with field capacity, transplanting in a flat bed under dry conditions, and transplanting in a raised bed under dry conditions. The sub-factor was the date of seedling production, which included June 2, June 12, and June 23. The rice cultivars, which were the sub-sub-factors, included Champa, Anbori, Germez-Paboland, and Daniyal.Results and DiscussionThe results of comparing the average of traits showed that the highest yield of paddy in the two years of the experiment was related to the flat planting bed and the planting date of 2 June (5190 kg.ha-1 in first year, 6536 kg.ha-1 in second year, respectively in Anbori, Germez-Paboland and Champa). Rice yield showed a high correlation with biological yield, number of panicles per square meter, panicle length and plant height. The lowest yield of paddy in the two years of the experiment belonged to the conventional bed (2811 kg.ha-1 in 12 June in first year, 2964 kg.ha-1 in 23 June in second year, respectively in Anbori, Germez-Paboland and Daniyal).ConclusionLong-term waterlogging in the method of gerbera cultivation has caused disturbances in the growth and production of the plant, resulting in a decrease in paddy yield. Therefore, it can be concluded that different beds for transplanting have a significant impact on rice crop production. Optimal management of these beds, through the application of appropriate planting dates and suitable cultivars, can effectively improve crop production. Also, according to the obtained results, although the Daniyal cultivars is a high-yielding cultivars, compared to the local varieties, it could not achieve better performance under the conditions of the treatments investigated in this experiment.