Short Paper Proceedings on Climate Change Adaptation in Agricultural Sector, Thailand 15 September, 2017 Institute of Industrial Science, the University of Tokyo PREFACE Meteorological Uncertainty caused by Global Climate Change would have significant impact on agricultural sector, because agricultural systems are strongly related with local climate condition. In Thailand, agriculture is major sector which producing 11% of GDP and 40% of employment. Ratio of irrigated agricultural land is about 30% and other 70% is rain-fed so that climate change makes agricultural production more unstable and also makes significant damage to the societies and economics in local area. To mitigate these issues, it is desirable to develop and disseminate enhanced adaptation systems including new varieties that are effective together with new cultivation methods, crop growth monitoring system to detect water stress condition, soil and water management to improve crop production. Furthermore, it is necessary to conduct reliable research to find ways to achieve economic betterment through agriculture under CC condition. In this workshop, we aim to review the current state and relevant research of above topics and to discuss about framework of CC adaptation strategies in agricultural sector, in Thailand. CONTENTS: 1. Effect of Water Salinity on Growth and Photosynthesis of Dendrobium Sonia ‘Earsakul’ 1 Patchareeya Boonkorkaew , Napasorn Chiewchookul , Poonpipope Kasemsap Praderm Wanichananan and Sudsaisin Kaewrueng 2. Establishment of Satellite-Based Drought Monitoring Platform in Thailand 4 Mongkol Raksapatcharawong, Watcharee Veerakachen, Kazuo Oki, Peerapon Prompitakporn, Chinnapoj Wongsripisant 3. Variability of Salinity Degree in Sal-Affected Soil in Northeast Thailand 8 Supranee Sritumboon, Somsak Ssukchan, Roengsak Katawatin, Mallika Srisutham, Pontip Phontusang, Koshi Yoshida, Kazuo Oki, Koki Homma, Masayasu Maki 4. Shallow Groundwater Channel Constrained by EM and Resistivity Techniques at Western Margin of Chao Phraya Basin, Suphanburi Province. 12 Desell Suanburi, Koshi Yoshida, Weerakaset Suanpaga, Naruekamon Janjirawuttikul and Sutthisak Manyon 5. Contributing Adaptation Strategy for Climate Change by Evaluating Agronomic Conditions through Measurement of LAI in rice 16 Koki Homma 6. Development of SDT Drought Index using Satellite Images 18 Kazuo Oki 7. Evaluation of the relationships between electric conductivity, sodium adsorption ratio before planting and leaf area index during growth period in Khon Kaen, Thailand 20 Masayasu Maki, Koki Homma, Taiki Saito, Koshi Yoshida, Kazuo Oki, Taichi Tebakari, Roengsak Katawatin, Mallika Srisutham, Supranee Sritumboon, Somsak Sukchan 8. Land Use Pattern and Population Dynamics in Flood Area in Thailand 22 Hiroaki Shirakawa 9. The Livelihood Strategies of Farming Households under Drought Stress in Rural Areas of Khon Kaen Province in the Northeastern Part of Thailand 24 Nao Endo 10. Basin Modelling for Evaluation of Available Water Resources and Nitrogen Runoff in Northeast Thailand 27 Yuki Jikeya and Koshi Yoshida Effect of Water Salinity on Growth and Photosynthesis of Dendrobium Sonia ‘Earsakul’ Patchareeya Boonkorkaew 1, Napasorn Chiewchookul 1, Poonpipope Kasemsap 1, Praderm Wanichananan 2 and Sudsaisin Kaewrueng 3 1 Department of Horticulture, Faculty of Agriculture, Kasetsart University, Postal Address 10900, Thailand Tel: +66 257 90308, Fax: +66 257 91951 ext. 112, E-mail: [email protected] 2 Nation Center for Genetic Engineering and Biotechnology, Postal Address 12120, Thailand 3 Department of Farm Mechanics, Faculty of Agriculture, Kasetsart University, Postal Address 10900, Thailand Abstract The effect of water salinity (250, 1000, 2000, 3000 and 4000 µS cm-1 of electrical conductivity (EC)) on growth and photosynthesis of 18-month-old Dendrobium Sonia ‘Earsakul’ plants during their flowering stage and grown in a 60% shading greenhouse is examined. The results showed that the number of leaves, number of roots, new shoots, new inflorescences, CO2 exchange rate and stomatal conductance decreased as the salt concentration in the water increased. Meanwhile, salinity had no effect on flower appearance. Therefore, D. Sonia ‘Earsakul' at the flowering stage can be irrigated with 40 ml of water with a 2,000 µS cm-1 EC per plant at 2-day intervals for 2 months. Keywords: Electrical conductivity, NaCl, Orchid, Saline water 1 INTRODUCTION filled with coconut husk. Two weeks before the experiment Thailand is the world’s largest producer and exporter commenced, the plants were acclimatized under the 60% of tropical orchids, including species such as shading greenhouse at Department of Horticulture, Faculty of Dendrobium, Ascocenda and Vanda. The production area Agriculture, Kasetsart University, Bang Khen, Bangkok, is mainly in Central Thailand, i.e. Samut Sakhon, Thailand. On average, air temperature was 30°C and Bangkok, Nakhon Pathom, Ratchaburi, Phra Nakhon Si relative humidity was 70%. The photosynthetic photon −2 −1 Ayutthaya, Pathum Thani and Nonthaburi provinces [1]. flux (PPF) ranged from 200 - 400 µmol m s . Plants -1 Dendrobium Sonia ‘Earsakul’ is one of the most important were fertilized once a week with 4 g L of N-P-K (21-21- -1 orchid plants, grown as cut- flowers and potted plants in 21) and 4 g L of N-P-K (10-52-13). Plants with a 1-5 cm Thailand. Meanwhile, high water quality is vital for orchid inflorescence length and 4-5 stems per plant were used in growth and development, ideally with a pH of 5.2-6.2 and this experiment. Observation occurred from September to electrical conductivity (EC) not exceeding 750 µS cm-1 December 2016. The experiment was conducted using a (0.75 dS m-1) or 0.5 g L-1 NaCl [2]. Good water resources completely randomized design with 15 replicates per are rain, tap water, canals and rivers. treatment. Irrigation water treatments included 5 different levels of salinity in EC, at 250 (tap water as a control Due to low water levels in Bhumibol dam and treatment), 1000, 2000, 3000 and 4000 µs cm-1. Saline Srinagarindra dam, the Royal Irrigation Department (RID) solutions were prepared using instant ocean sea salt cannot release water into Chao Phraya River, one of the (NaCl) mixed with tap water for each treatment. and two main sources of Bangkok’s tap water. Low water Irrigated saline water was sprayed on the entirety of each levels in the Chao Phraya River cause seawater intrusion, plant using 40 ml per plant at 2-day intervals for 2 leading to saline water. In 2014, Thailand suffered the months. worst water salinity levels in more than a century; in February 15-16, 2014, saline levels downriver (1.80 g L-1) were much higher than the standard salt concentration of 2.2 Measurements of growth and flower quality water that supplies homes, which must not exceed 0.25 g 2.2.1 Growth: counted the number of leaves (whole -1 L [3]. In 2015, the salt concentration of water in Tha plant), number of fresh roots and number of new -1 Chin River was much higher (7.0 g L ), and the estimated inflorescences in the same pseudobulb. Data were orchid cultivation area affected by this water salinity was collected once a month for 2 months approximately 1,600 ha (50% of total production area) [4]. 2.2.2 Flower: recorded the number of open flowers Salinity, in irrigation water, is one of the major per inflorescence, inflorescence length, flower width and environmental limiting factors for growth and productivity flower height of orchids. Since orchid farmers do not know much about the effect of salinity, they are afraid of using saline water 2.2.3 Percentage of new shoot and percentage of to irrigate mature plants, especially in the flowering stage. new inflorescence Therefore, the objective of this research was to determine the interaction between water salinity level and duration of 2.3 Photosynthesis parameters measurement growth, flower quality and photosynthesis parameters of Photosynthesis parameters of Dendrobium Sonia Dendrobium Sonia ‘Earsakul’. ‘Earsakul’ such as CO2 exchange rate (CER) and stomatal conductance (gs) were monitored using a 2 MATERIAL AND METHODS Portable Photosynthesis System; LI-6400XT (LI-COR 2.1 Plant material Inc., Lincoln, NE, USA). The CO2 concentration in the chamber was 400 ± 10 ppm. The leaf surface was 18-month-old plants (flowering stage) of Dendrobium measured using a Standard 2 x 3 cm Chamber (6400-08 Sonia ‘Earsakul’ were propagated by tissue culture and Clear Chamber Bottom, LI-COR, USA). Leaf samples grown in plastic pots measuring 3½ inches, which were were measured from the third leaf (from the top) of a front 1 pseudobulb, which was flowering, with 3 data measurements per leaf and 3 leaves per treatment every 10 a 250 1000 2000 3000 4000 (A) 2 hours from 2 to 6 a.m. after being treated with saline a water for 1 and 2 months. 8 a 6 b 2.4 Statistical analysis b The data were analyzed using SAS and the mean 4 results were compared using Duncan’s multiple range test b 2 c (DMRT) at a 0.01 and 0.05 probability level. roots of Number c b 0 3 RESULTS AND DISCUSSION 18 0 1 2 250 1000 2000 3000 4000 16 Time (month) (B) The results show that, after irrigating with treatments of saline water for one month at 1,000, 2,000, 14 a ab a 12 3,000 and 4,000 µS cm-1, the number of new roots were b b reduced, to 2.3, 3.6, 5.8 and 6.4 roots, respectively, 10 8 producing fewer than that of the control (Fig.1A). 6 Additionally, the number of leaves decreased when the EC was higher than 3000 µS cm-1 (Fig.1B). After 2 4 Number of leaves of leaves Number months, leaf number was decreased under 3,000 and 2 4,000 µS cm-1 saline water, as compared with 2.4 and 2.5 0 0 1 2 leaves under the control. New shoot sprouting similarly decreased, at 42.9, 71.4 and 71.4% under 2,000, 3,000 Time (month) and 4,000 µS cm-1, respectively (Fig.2).