Page 140 - Breeding and regulatory opportunities, Renaud

Chapter 4

while others varied in rank. The open pollinated cultivars consistently ranked

at the bottom, while a group of Fcultivars displayed the greatest head weight
1
across Management systems.

In the Maine trials all cultivars from organic trials outperformed those grown in

conventional trials for head weight. In the Fall trials four of the ive top ranking

cultivars were the same between the organic and conventional trials (‘Packman’,

‘Fiesta’, ‘Everest’ and ‘Green Goliath’), see Table 4.7a. ‘Green Magic’ was the top

performing cultivar in organic but ranked 10th in conventional with a signiicant

head weight diference between Management systems. In the Maine organic

Spring trials there were more rank changes. The top two performing cultivars

(‘Fiesta’ and ‘Green Magic’), were the 7th and 8th ranked cultivars in conventional,

while ‘Imperial’ ranked 3rd in both systems. The best performing cultivars

under conventional (‘Marathon’, ‘Nutribud’, ‘Early Green’) did not perform

comparatively well under organic (rank 11, 12 and 18, respectively)

The results for the Oregon Fall trials for head weight indicated that three of

the ive top performing varieties in both organic and conventional systems

were the same: ‘Green Magic’, ‘Maximo’ and ‘Batavia’), see Table 4.7b. All three

cultivars produced higher yields in the organic trials compared to the

conventionally paired trial. ‘Imperial’ ranked #1 in conventional, while it ranked

#6 in organic, and similar to the Maine trials, ‘Marathon’ ranked high in Oregon

organic (#4) and much lower (#13) in conventional (signiicantly diferent

than top two cultivars, ‘Imperial’ and ‘Green Magic’), with a signiicant head

weight diference in cultivar performance between management systems.

Conventional 5th and 6th ranked cultivars, ‘Belstar’ and ‘B1 10’ dropped in rank to

9th and 11th in organic, respectively (signiicantly diferent from ‘Green Magic’,

but not other cultivars in organic).

122