Seed germination

All harvest treatments yielded germinable seeds. The time course for germination typically showed a lag phase of 5-6 days before germination was observed, followed by consistent germination for the following 14 days. For most treatments there was little additional germination before the completion of the experiment, 36 days after imbibition. The cumulative percentage of germination at 21 days after imbibition was analysed (using arcsine-transformed values) by harvest, inflorescence segment and post-storage seed size (Table 4.4). There were significant differences in germination after 21 days between harvests (P < 0.05), with Harvest 1 having the highest mean germination (89%). In each of the four harvests, seeds from capsules in the central segments of the inflorescences gave the highest mean germination values after 21 days. However, for the pooled values for segments, germination was significantly lower (P < 0.05) only for seeds from the distal segments (Table 4.4). Although, in the majority of germination tests, large seeds recorded higher germination values than small seeds, this trend was not significant at 21 days after imbibition, and this difference had narrowed further after 36 days.

From individual tests of inflorescence segment and seed-size combinations, the highest and narrowest range of values for germination were for seeds that had matured while still attached to the plant (Harvest 1). Similar germination values were recorded for some seeds harvested from detached inflorescences, but the range of values recorded was much higher. Small seeds harvested from the distal segment of detached inflorescences consistently gave significantly lower cumulative

Table 4.3. The total and relative proportions of freshly harvested Bulbine bulbosa seeds of three size categories from three inflorescence segments (i.e. proximal, central and distal).

Seed number per size Percentage of seed per size Harvest Inflorescence category per inflorescence category per inflorescence treatment segment segment segment

Table 4.3. The total and relative proportions of freshly harvested Bulbine bulbosa seeds of three size categories from three inflorescence segments (i.e. proximal, central and distal).

Seed number per size Percentage of seed per size Harvest Inflorescence category per inflorescence category per inflorescence treatment segment segment segment

L

M

S

L

M

S

1 (mature)

Proximal

339

297

17

52

45

3

Central

462

236

9

65

33

1

Distal

460

1 81

5

71

28

1

Post

137

28

5

63

36

2

Total

1398

742

36

64

34

2

2 (early)

Discard

39

26

1

59

39

2

Proximal

405

256

1

61

39

0

Central

357

283

15

55

43

2

Distal

1 62

268

42

33

58

9

Total

963

833

59

52

45

3

3 (intermediate)

Discard

72

1 08

32

34

51

15

Proximal

277

378

74

38

52

10

Central

296

375

69

40

51

9

Distal

1 22

222

91

28

51

21

Total

695

975

234

37

51

12

4 (late)

Discard

185

179

21

48

46

5

Proximal

241

284

24

44

52

4

Central

253

272

17

47

50

3

Distal

1 29

277

45

29

61

10

Total

623

833

86

40

54

6

Total (all harvests)

3647

3383

415

49

45

6

Seed size categories: L = large (>2.0 mm); M = medium (<2.0 mm and >1.5 mm); S = small (<1.5 mm and >1.2 mm); Post = seeds harvested from capsules that set after harvest commenced; Total = sum of all harvested seed (excludes discarded seed); Discard = seed collected from capsules that were discarded at harvest.

Seed size categories: L = large (>2.0 mm); M = medium (<2.0 mm and >1.5 mm); S = small (<1.5 mm and >1.2 mm); Post = seeds harvested from capsules that set after harvest commenced; Total = sum of all harvested seed (excludes discarded seed); Discard = seed collected from capsules that were discarded at harvest.

germination values after 21 days (P < 0.05) than other combinations of seed size and inflorescence segment (data not shown).

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