Physiology of Flowering in Lychee Trees grown in Mountainous Areas of Thailand Daruni Naphrom Pittaya Sruamsiri Department of Horticulture, Faculty of Agriculture, Chiang Mai University, Thailand 52 Chiti Sritontip Agricultural Research and Training Center, Thailand Martin Hegele Jens Wuensche Department of Special Crop Cultivation and Crop Physiology, Hohenheim University, Stuttgart, Germany
Chiang Rai Payao Low temperature cultivars cv. Hong Huay, Chakapad, Nan Kimjeng Chiang Mai Samutsongkram Moderate low temperature Cultivars cv. Kom Lychee production areas in Thailand Chiang Mai 8,16 ha Chiang Rai 6,532 ha Nan 2,526 ha Payao 2,431 ha Samutsongkram 1,449 ha
Lychee growing areas in Chiang Mai 12 msl 1,25 masl 75 msl 3 msl CM City Ping river
Growth cycle of lychee tree (on season) Nov Cool period
Growth cycle of lychee tree (off season) July-Aug April-June Nov- Dec Jan-March
Factors affecting on flowering Warm temperature Wet condition Low temperature Dry condition Girdling Endogenous Factors Hormones, C/N etc. Vegetative growth Reproductive growth
Under canopy area of lychee tree
Methodolody 1. Investigated environmental conditions at 75 and 12 msl in 27 2. Girdling lychee trees
Non girdling Girdling
Data collection 1. Climate conditions; temperatures, rain fall and RH 2. Plant conditions; photosynthesis, carbohydrate, hormonal content, flowering and yield
Results and Discussion Year round temperatures at 35, 75 and 1,2 msl Temperature( C) 4 35 3 25 2 15 1 5 Flowering time (off-season) Flowering time (on-season) 35 masl max T 35 masl min T 75 masl max T 75 masl min T 1,2 masl max T 1,2 masl min T Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 27 month
Soil temperatures at 75 and 1,2 msl in 27 Flowering time (off-season) Flowering time (on-season) Temperature ( C) 3 25 2 15 1 5 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month 27 75 masl 1,2 masl
%RH and Rainfall at 75 and 1,2 msl Flowering time (off-season) Flowering time (on-season) 12 5 % RH 1 8 6 4 2 4 3 2 1 mm. %RH 12 masl %RH 75 masl Rain 12 masl Rain 75 masl Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month 27
Photosynthesis Photosynthesis 6 5 Flowering 4 3 2 1 Girdling Non-girdling 14 28 42 56 7 84 Days
Stomatal Conductance 35 mmol/m 2 s -1 3 25 2 15 1 Flowering Girdling Non-girdling 5 14 28 42 56 7 84 Days Statistics Treatment Stomata Conductance (mmol/m 2 s -1 ) Day 14 Day 28 Day 42 Day 56 Day 7 Day 84 Girdling 184.5 279.64 118.72 156.3 27.91 123.63 Non-girdling 196.79 33.16 131.12 111.89 153.91 82.48 significant ns ns ns * * *
Total Nonstructural Carbohydrate (75 msl) Total Nonstructural Carbohydrate of Litchi Leaves mg.glucose eq./g. dry wt. 25 2 15 1 5 Flowering Girdling Non-girdling 1 14 28 42 56 7 84 Days Statistics Total Nonstructural Carbohydrate of Litchi Leaves on 75 masl Treatment 1 14 28 42 56 7 84 Girdling 142a 171 163 22 227 237a 2a Non girdling 18b 16 196 231 29 199b 161b significant * ns ns ns ns * *
Total Nonstructural Carbohydrate (12 msl) Total Nonstructural Carbohydrate of Litchi Leaves mg.glucose eq./g. dry wt. 3 25 2 15 1 5 1 14 21 28 35 42 49 56 Days Flowering Girdling Non-girdling Statistics Treatment Total Nonstructural Carbohydrate of Litchi Leaves on 12 masl 1 14 21 28 35 42 49 56 Girdling 166 143 124 14 24 272a 195 25 Non girdling 183 159 16 163 195 221b 21 228 significant ns ns ns ns ns * ns ns
Hormonal Contents Z/ZR concentrations in lychee shoot tips 75 msl 1,2 msl 18 14 Z/ZR conc. ( n g / g.d W ) 16 14 12 1 8 6 4 2 Flowering time Z/ZR conc. ( n g /g.d W ) 12 1 8 6 4 2 Flowering time 1 2 3 4 5 6 7 Time of sampling 1 2 3 4 5 6 7 8 Time of sampling
IAA concentrations in lychee shoot tips 75 msl 1,2 msl IA A co n c. ( n g /g.d W ) 8 7 6 5 4 3 2 1 IA A co n c. ( n g /g.d W ) 6 5 4 3 2 1 1 2 3 4 5 6 7 Time of sampling 1 2 3 4 5 6 7 8 Time of sampling
GAs concentrations in lychee shoot tips 75 msl 1,2 msl 25 2 18 GAs conc. ( n g /g.d W ) 2 15 1 5 G As conc. ( n g / g.d W ) 16 14 12 1 8 6 4 2 1 2 3 4 5 6 7 Time of sampling 1 2 3 4 5 6 7 8 Time of sampling
Table 1 Days of flowering after treatment, 27 Treatments Days of Flowering after treatment (Days) 12 msl 75 msl Girdling 38.5 59.5 Non girdling Non flowering 56 significant * ns Table 2 Percentage of flowering, 27 Treatments Girdling Non girdling significant Percentage of Flowering (%) 12 msl 75 msl 27.55 19.325 Non flowering 22.625 * ns
Production of Litchi from Experimental Fields at 75 and 1,2 msl, 27 Kg/Rai 8 7 6 5 4 3 2 1 27 75 masl 12 masl Year
Production of Litchi at 75 msl in 27
Flowering situation in 28 12 msl 4 msl 75 msl
Conclusion 1. The temperatures at 75 and 12 msl were not different before flowering period. 2. High RH and rainfall were found at 12 msl. 3. Girdling increased photosynthesis rate, stomatal conductance and TNC during flowering period. 4. Z/ZR and IAA in shoot tips showed high concentrations before flowering. 5. GAs seemed to decrease before flowering. 6. Lychee trees at 75 msl produced more flowering than those 1,2 msl
Acknowledgement I would like to thank: - SFB and NRCT for financial support - Research Team in sup project D1