DOI: 10.25739/ej8x-3b24
title: Saengwilai_Cassava_2019

description: The folder contains images and data sets of pot and field experiments. For DIRT_Cassava_pot.csv and Cassava_pot_Images file: The pot experiment was conducted at Mahidol University(Salaya campus) in Nakhon Pathom, Thailand. The stem cuttings were placed vertically in the soil such that two-thirds of the stem was below the soil line. We used 24-cm-tall white plastic pots with a diameter of 25 cm at the top and 17 cm at the bottom. Each pot contained 5 kg of organic growth media containing rain tree leaf soil and bamboo soil (1 : 1 volume ratio). Water-holding capacity was measured and processed as described by Noggle and Wynd (1941), and it was calculated as the percentage from the ratio of mass of the water in saturated soil to the mass of the saturated soil. The soil in each pot was saturated with water and drained for a day to evaluate percentage of soil water content that was determined by gravimetric measurement (Evett, 2008). We found that the water-holding capacity in the pot system was 52.48% and the soil water content was 83%. We planted five biological replicates under well-watered and drought conditions. The plants were placed outside for 30 days and were watered every other day with 1 L of water. Twenty-four days after planting (DAP), 20 g of fertilizer containing 16% each of nitrogen, phosphorus, and potassium (16-16-16) per pot was applied. According to Adu et al. (2018), cassava has the highest relative growth rate during the first 30 DAP and the growth rate is subsequently decreased until nearly constant after 30 to 60 DAP; therefore, drought treatment was applied at 30 DAP to allow time for plants to acclimate to the system and yield information relevant to developmental processes. All plants were transferred into a growth shelter made of transparent plastic sheets to protect the plants from rainwater. To simulate drought conditions, half of the plants received no water from 30 to 90 DAP, after which they were harvested and phenotyped. The total amount of water that the plants received in the well-watered and drought treatments were approximately 45 L and 15 L, respectively. Soil water content decreased to 46.95% and 28.36% at seven and 14 days after drought treatment, respectively. At this time, the plants showed significant reduction in height and number of leaves under drought in all genotypes. For DIRT_Cassava_field.csv and Cassava_field_image file; The field experiment was conducted at the Rayong Field Crops Research Center, Mueng, Rayong, Thailand.Three genotypes (R5, R9, and R11) were planted under well-watered and drought treatments between April 2016 to April 2017. The total amount of rainfall during this experiment was 1714.3 mm. Each plot had 700 plants, and seven replicates were harvested in this trial. The distance between rows and between plants was 1 m. The plants were watered once per week in the first two months. We followed the fertilization regime recommended by the Thailand Department of Agriculture. This regime applies 87.5 kg.ha?1 of urea, 54.81 kg.ha?1 of diammonium phosphate (18-46-0), and 271.56 kg.ha?1 of potassium chloride (0-0- 60). After two months of growth, well-watered plants received irrigated water every other day, while the drought treatment plants were rainfed and did not receive additional water. Shoot and root traits were quantified at 10 months (first trial) and 12 months (second trial) after planting.