Researcher: Ma. Lourdes S. Edaño University of the Philippines, Los Baños

1. Factors Affecting the Phyllochron: The Scientific Bases for SRI Ma. Lourdes S. Edaño University of the Philippines, Los Ba ñ os

7. Table 1. Phyllochron table of KATAYAMA indicating the number and location of tillers initiated during each stage of development in rice when tillers are appearing in an accelerating manner PHYLLOCHRON (sequence) 1st 4th 5th 6th 7th 8th 9th 10th 11th 12th 13th total Days 18-26 23-33 28-40 33-47 38-54 43-61 48-68 53-75 58-82 63-89 Main stalk 1 1 Primary tillers 1 1 1 1 1 1 6 2 nd row tillers 1 2 3 4 5 6 5 4 30 3 rd row tillers 1 3 6 10 15 21 56 4 th row tillers 1 4 10 20 35 5 th row tillers 1 5 6 sum 1 2 3 5 8 13 21 33 53 84 134 134

8. Figure 1. Tillering dynamics of rice shoots based on Katayama’s analysis of rice growth (after Laulani é)

10. Table 2. Phyllochron length (days/leaf) for each leaf of rice as affected by variety and by age of seedlings in the dry season, 2003 (Dobech, 2004). Age of Seedling (in days) LEAF NUMBER ON THE MAIN STEM 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Total Leaves Elon-Elon 8 - - 4 3 3 3 3 3 4 6 7 8 9 9 7 13 15 - - 3 3 3 3 3 3 4 5 7 8 9 8 7 13 20 - - - 7 6 4 4 5 7 8 9 9 8 - - 10 25 - - - - 8 6 4 4 6 8 8 9 7 - - 9 PSBRc-82 8 - - 3 3 3 3 3 3 4 5 7 8 8 7 - 12 15 - - 3 3 3 3 3 3 4 6 7 7 7 7 - 12 20 - - - 7 4 3 3 4 4 5 7 7 7 - - 10 25 - - - - 8 6 4 3 4 7 8 8 7 - - 9

11. Table 3. Phyllochron length (days/leaf) for each leaf of rice as affected by variety and by age of seedlings in the wet season, 2003 (Dobech, 2004). Age of Seedlings (in days) LEAF NUMBERS ON THE MAIN STEM 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 T.Leaves Elon-Elon 8 - - 4 3 3 3 4 3 3 3 4 6 7 7 8 10 7 - 15 15 - - 4 3 3 3 4 3 3 3 4 5 6 7 8 10 7 - 15 20 - - - 6 4 4 4 4 5 6 7 7 8 10 7 - - - 12 25 - - - - 7 6 5 5 4 5 6 7 8 10 8 - - - 11 PSBRc-82 8 - - 3 3 3 3 3 3 3 3 4 6 6 7 7 8 - - 14 15 - - 3 3 3 3 3 3 3 3 4 5 6 7 6 7 - - 14 20 - - - 6 5 3 3 4 4 5 6 7 6 7 7 - - - 12 25 - - - - 6 5 4 4 4 5 5 6 6 8 7 - - - 11

12. Table 4. Phyllochron length in rice as affected by seedling age in the dry and wet seasons, 2003 (Dobech, 2004). PHYLLOCHRON (day/leaf) Seedling Age Dry Season Wet Season 8 5.3 c 4.7 b 15 4.9 d 4.5 c 20 6.0 b 5.6 a 25 6.5 a 6.2 a cv 4.9% 4.8%

14. Table 4. Length of rice phyllochron as affected by variety in the dry and wet season, 2003 (Dobech, 2004). PHYLLOCHRON (day/leaf) Variety Dry Season Wet Season Elon-elon 5.7 a 5.5 a PSBRc-82 5.1 b 5.1 b cv 4.9% 4.8%

16. Table 5. Number of productive tillers per hill of rice as affected by seedling age in the dry and wet season, 2003 (Dobech, 2004). NO. OF PRODUCTIVE TILLERS PER HILL Seedling Age Dry Season Wet Season 8 26.2 a 60.8 a 15 26.2 a 59.1 a 20 25.7 a 45.9 b 25 17.4 b 36.9 c CV 4.1 8.6%

18. Table 6. Length of phyllochron of rice as affected by spacing in dry and wet seasons, 2003 (Dobech, 2004) PHYLLOCHRON (Day/Leaf) SPACING Dry Season Wet Season 20 x 20 cm 6.1 a 5.6 a 30 x 30 cm 5.5 b 4.9 b 45 x 45 cm 5.4 b 4.8 c CV 1.5% 2.1%

20. Table 7. Number of productive tillers per hill of rice as affected by the interaction of spacing and variety in the dry season, 2003 (Dobech, 2004) NUMBER OF PRODUCTIVE TILLERS PER HILL VARIETY Spacing 20 x 20 cm 30 x 30 cm 45 x 45 cm Elon–Elon 16.2 c 28.6 a 29.7 a PSBRc-82 16.00 c 21.8 b 23.3 b

21. Table 8. Number of productive tillers per hill of rice as affected by the interaction of spacing and variety in the wet season, 2003 (Dobech, 2004) NUMBER OF PRODUCTIVE TILLERS PER HILL VARIETY SPACING 20 x 20 cm 30 x 30 cm 45 x 45 cm Elon–Elon 20.4 d 37.9 c 63.9 a PSBRc-82 25.1 d 37.7 c 54.8 b