Genetic analysis of glucosinolate content in Indian mustard (Brassica juncea L.)

Abstract

Glucosinolates are group of plant thioglucosides found principally among the members of family Brassicaceae. The vegetative tissue and seed of Cruciferous contain one or more of the 120 known glucosinolates [1]. Glucosinolates co-exist with an enzyme called myrosinase which mediates their breakdown to a range of active compounds, isothiocyanates, nitrites, oxazolidimethiones which rendered the seed meal unsuitable for use as animal feed, especially for nonruminants. The breakdown products of glucosinolates are goitrogenic [2]. The toxicity manifestation of these products is goiter, as a result of iodine uptake impairment, liver damage, increased liver weight, reduced body weight and food intake in farm animals. The presence of high glucosinolates (80-125 I.l moles/g defatted seed meal) in seed meal of cultivars of Indian mustard (B. juncea L.), the predominant crop among rapeseed-mustard, occupying nearly 80% of the total cropped area under these crops in the country, is a strong non -tariff barrier in international market and fetches low prices. Reducing glucosinolate content in seed meal would also improve the feeding value of mustard meal for livestock especially for non- ruminants. In the breeding programme d-efforts are underway to reduce the level of glucosinolate content up to the internationally acceptable norms « 30 I.l moles/g defatted seed meal). Knowledge of genetic architecture of a character is imperative for the success of the breeding programme. Information on this aspect for glucosinolate content in Indian mustard is meager [3]. Therefore, the present investigation attempts to study the genetics of glucosinolate content in Indian mustard.