66

Middletown 4.1 5.2 bcd 3.3 h 0.28

Clone 2002 Yield (kg) / tree 2004 Biennial bearing indexz

2003 2004 2002-2004

Mitchell 1.2 2.9 d 8.4 cdefgh 0.47

NC-1 1.6 4.1 cd 7.2 defgh 0.40

Overleese 2.1 3.4 d 4.6 efgh 0.34

PA-Golden 6.8 8.6 ab 12.1 abcd 0.18

Potomac 2.5 2.9 d 9.7 abcdef 0.53

Rappahannock 1.5 4.8 bcd 10.0 abcde 0.52

Shenandoah 4.2 7.5 abc 8.8 bcdefg 0.50

Sunflower 6.5 5.9 bcd 15.1 a 0.35

Taylor 4.0 5.0 bcd 12.0 abcd 0.23

Taytwo 3.6 10.1 a 6.6 defgh 0.20

Wabash 3.9 5.5 bcd 4.5 fgh 0.42

Wells 4.5 7.2 abc 10.0 abcde 0.46

1-23 4.3 6.8 abcd 10.8 abcd 0.45

1-68 2.8 4.0 cd 7.9 cdefgh 0.23

2-10 3.1 5.6 bcd 11.5 abcd 0.48

2-54 2.8 2.9 d 7.7 cdefgh 0.42

3-11 2.5 2.8 d 12.1 abc 0.28

3-21 2.4 3.8 cd 9.7 abcdef 0.42

5-5 1.4 3.8 cd 3.4 h 0.33

7-90 3.2 4.4 bcd 10.0 abcde 0.41

8-20 4.0 2.4 d 12.7 abc 0.58

9-47 3.5 6.3 bcd 4.4 gh 0.34

9-58 3.6 5.6 bcd 15.8 a 0.34

10-35 3.8 6.0 bcd 14.2 ab 0.31

11-13 3.1 5.8 bcd 10.9 abcd 0.33

P-value NS**** NS

LSD 7.2 8.5 6.7 0.33

mean 3.5 5.3 9.3 0.38

block** NS NS NS

The Biennial bearing index (BBI) was calculated on the basis of the Pearce and Debusek-Urbank formula (14): BBI = 1 / (n-1) X \{ | (a_{2} - a_{1}) | / (a_{2} + a_{1}) + | (a_{3} - a_{2}) | / (a_{3} + a_{2}) ... + | (a_{(n)} - a_{(n-1)}) | / (a_{(n)} + a_{(n-1)}) \} where n = number of years, and a_{1}, a_{2}, ..., a(n-1), an = yield of corresponding years.

When examining cultivar and advanced selection relationships, significant correlations were noted between TCA (r = 0.49; P<0.01), number of fruit per tree (r = 0.79; P<0.001), and cumulative yield (r = 0.66; P<0.001) for cultivars and advanced selections in both plantings.

Some differences were observed between the two Kentucky pawpaw trials in terms of vigor and yield of selections, but generally clones performed similarly in comparison to each other at the two locations. TCA, number of fruit per tree, and cumulative yield for cul-