Page 121 - Breeding and regulatory opportunities, Renaud

Broccoli crop improvement

4.1 Introduction

Continued growth in demand in the organic sector has spurred an increase in

organic crop production area in the United States (US) with over two million

hectares in 2011 (Willer and Kilcher, 2012). The seed industry is challenged to

satisfy the demands of organic agriculture, and often does not understand the

special requirements of an unfamiliar agricultural system that is characterized

by a greater diversity of requirements and criteria compared to conventional

management (Mäder et al., 2002). Organic farms often difer substantially from

non-organic counterparts in the complexity of their crop rotations, number

of crops, production area, and market outlets. Organic farmers refrain from

using synthetically derived chemical inputs and rely largely on biological self-

regulatory processes to maintain yield leaving fewer tools to manage crop

production environments (Messmer et al., 2012; Wolfe et al., 2008). Thus, organic

farmers need cultivars that are stable across a range of conditions, rather than

varieties that are high yielding under optimal conditions, but prone to lose that

yield advantage due to disease susceptibility or an inability to utilize available

nutrients eiciently (Lammerts van Bueren et al., 2002).

Broccoli, a signiicant crop in organic agriculture due to its market demand

as well as its nutritional contribution to the USA diet (Verkerk et al., 2009),

was grown on 743,088 production acres (300,717 ha) and generated U.S.

$47,629,515 in sales in 2011 (USDA NASS, 2012). The main conventional

fresh market broccoli production areas in the USA are California and Arizona.

Broccoli cultivars in the USA have been bred primarily for the agro-climatic

requirements of these regions. Secondary commercial broccoli producing areas

are Maine and Oregon which are characteristically cool continental and cool

Mediterranean type climates, respectively and difer signiicantly from those

of California and Arizona. Organic production in the USA is comprised of small

acreages scattered across the country in a broad range of environments to

service local and diverse food markets (USDA ERS, 2008; USDA NASS, 2012).

These producers are dependent on the commercial cultivar assortment

available that were developed predominantly for California and Arizona. The

production environments for Oregon and Maine may be more representative

of the growing conditions faced by organic growers located at higher latitudes

on the east and west coasts.

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