Ogtr document

The Biology of
Brassica napus L. (canola) and Brassica juncea (L.) Czern. & Coss. (Indian mustard)

Version 2.1: February 2017

This document provides an overview of baseline biological information relevant to risk assessment of genetically modified forms of the species that may be released into the Australian environment. Cover photo of canola courtesy of Brian Weir.

For information on the Australian Government Office of the Gene Technology Regulator visit

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Table of Contents

Abbreviations used in this document 4

Preamble 5

Section 1 Taxonomy 6

1.1 Brassicaceae family 6

1.2 Brassica genus 6

Section 2 Origin and cultivation 8

2.1 Centre of origin, diversity and domestication 8

2.2 Production and commercial uses 9

2.3 Cultivation in Australia 10

2.3.1 Commercial propagation 10

2.3.2 Scale of cultivation 11

2.3.3 Potential for expansion of B. napus and B. juncea growing regions 13

2.3.4 Cultivation practices 16

2.4 Crop Improvement 19

2.4.1 Breeding in Australia 21

2.4.2 Genetic modification 26

Section 3 Morphology 26

3.1 Plant morphology 26

3.2 Reproductive morphology 27

Section 4 Development 28

4.1 Reproduction 28

4.2 Pollination and pollen dispersal 28

4.3 Fruit/seed development and seed dispersal 29

4.3.1 Fruit and seed development 29

4.3.2 Seed dispersal 30

4.4 Seed germination and seed dormancy 31

4.5 Vegetative growth 34

Section 5 Biochemistry 35

5.1 Toxins 35

5.1.1 Erucic acid 35

5.1.2 Glucosinolates 36

5.2 Allergens 37

5.3 Other undesirable phytochemicals 38

5.4 Beneficial phytochemicals 38

Section 6 Abiotic Interactions 40

6.1 Abiotic stresses 40

6.1.1 Nutrient stress 40

6.1.2 Heavy metals 40

6.1.3 Temperature, water and salinity stress 41

Section 7 Biotic Interactions 41

7.1 Weeds 41

7.2 Pests and pathogens 42

7.2.1 Pests 42

7.2.2 Pathogens 42

Section 8 Weediness 45

8.1 Weediness status on a global scale 45

8.2 Weediness status in Australia 45

8.2.1 Cultivated areas 47

8.2.2 Non-cropped disturbed habitats 48

8.2.3 Undisturbed natural habitats 48

8.3 Control measures 49

8.4 Weed risk assessment of B. napus and B. juncea 49

Section 9 Potential for Vertical Gene Transfer 50

9.1 Pollen flow and cross-pollination rates 50

9.2 Intraspecific crossing 50

9.2.1 Crosses with oilseed subspecies 51

9.2.2 Crosses with vegetables and forage rape subspecies 52

9.3 Interspecific crossings 52

9.4 Intergeneric crossings 56

9.5 Bridging as a means of gene transfer 57

References 59

Appendix 1 Weed Risk Assessment 80

Abbreviations used in this document

ACT Australian Capital Territory

AFLP Amplified Fragment Length Polymorphism

AOF Australian Oilseed Federation

APVMA Australian Pesticides and Veterinary Medicines Authority

ASA Australian Seeds Authority

BWYV Beet western yellows virus

CaMV Cauliflower mosaic virus

Canola Canadian oil, low acid

CMS Cytoplasmic male sterility

DNA Deoxyribonucleic acid

DPI Department of Primary Industry

FSANZ Food Standards Australia New Zealand

GM Genetically modified

GRDC Grains Research & Development Corporation

ha Hectare

HOLL High Oleic, Low Linolenic

IT Imidazolinone tolerant

ITC Isothiocyanates

ITSA International Seed Testing Association

Mbp Megabase pair

Mya Million years ago

n Haploid number of chromosomes

NGS Next Generation Sequencing

NSW New South Wales

NT Northern Territory

OECD Organisation for Economic Co-operation and Development

PTDI Provisional Tolerable Daily Intake

QLD Queensland

QTL Quantitative Trait Locus

RFLP Restriction Fragment Length Polymorphisms

RNA Ribonucleic acid

SA South Australia

SNP Single Nucleotide Polymorphism

spp. Species

SRAP Sequence Related Amplified Polymorphism

SSR Simple Sequence Repeat

TAS Tasmania

TILLING Target Induced Local Lesions in Genomes

TT Triazine Tolerant

TuMV Turnip mosaic virus

TuYV Turnip yellows virus

VIC Victoria

WA Western Australia

Preamble

This document describes the biology of Brassica napus L. and B. juncea (L.) Czern. & Coss., with particular reference to the Australian environment, cultivation and use. Information included relates to the taxonomy and origins of cultivated B. napus and B. juncea, general descriptions of their morphology, reproductive biology, biochemistry, and biotic and abiotic interactions. This document also addresses the potential for gene transfer to occur to closely related species. The purpose of this document is to provide baseline information about the parent organisms for use in risk assessments of genetically modified B. napus and B. juncea that may be released into the Australian environment.

The term ‘canola’ is derived from Canadian oil, low acid, proposed by the Western Canadian Oilseed Crushers’ Association in 1978 to refer to varieties^a of B. napus with low erucic acid and glucosinolate content. In 1980, the trademark was transferred to the Canola Council of Canada (Eskin 2013). Canola now refers to three Brassica species that meet these compositional criteria: B. napus (also known as Argentine canola); B. rapa (also known as Polish canola); and B. juncea (also known as Indian mustard). For the purpose of this document, B. napus canola and B. juncea canola will be used to refer respectively to oilseed varieties of B. napus and B. juncea that meet internationally agreed compositional criteria. Canola will be used as a generic term to designate both species. Varieties not meeting agreed compositional criteria will be referred to as rapeseed and/or Indian mustard.

Canola is grown primarily as an oilseed, from which oil is extracted. The oil is used for cooking and in food products such as margarine. Canola seeds yield 35-45% oil. A by-product of the oil extraction process is the generation of a high-protein meal that may be used as animal feed. Worldwide, canola is the third most important edible vegetable oil crop after soybean and palm oil and the third most important oil meal crop after soybean and cotton (Snowdon et al. 2007).

The highest annual canola production occurs in the European Union, China, Canada, and Australia. Initial trials in Australia of B. napus and B. rapa began in the early 1960s, with the two crops first grown commercially in 1969. It was another decade before canola varieties became available. Today, in Australia commercial B. napus canola production occurs mainly in New South Wales, Victoria, South Australia and Western Australia, with an area of over 2.7 million hectares planted in 2013-2014 (ABARES 2015). The distribution of B. napus canola production coincides with the wheat belt, with B. napus often grown as a break crop between cereal rotations.

B. juncea, commonly known as Indian mustard (or rai) (OECD 2012) is cultivated worldwide as a condiment (mustard), oilseed or vegetable crop with the greatest commercial production occurring in India and Canada. In Australia, commercial production occurs on a relatively small scale with several thousand hectares planted annually in western Victoria, central New South Wales and/or South Australia.