Growth, yield, and oil content of Brassica species under Brazilian tropical conditions

ABSTRACT Brassica oilseed species are becoming increasingly popular for industrial uses, with emphasis on biodiesel. It is of importance to evaluate the yield and oil production potential of nontraditional oilseeds for use as feedstock in Brazil. In this study, growth, yield, and oil content and their correlations were determined for eight accessions of B. juncea and B. rapa in two years under tropical conditions of southeastern Brazil. Significant variation was observed between B. juncea and B. rapa accessions for yield components and oil content. B. rapa was the earliest maturing and had the highest oil content, whereas B. juncea had the highest number of pods and the highest yield and oil yield. Brassica rapa accessions flowered early, with an average cycle of 97 days, whereas B. juncea reached maturation after 110 days on average. Accessions were grouped according to the oil content of each species, with the most promising accessions having an oil content of 45–47%. Accessions of Brassica species had high oil yields, reaching 910 kg ha-1 of oil yield for B. juncea PI 180266. There was a linear correlation between oil content and thousand seed weight, pod length, and seeds per pod of the Brassica species accessions. Considering oil content and oil yield across years, Brassica species show promise as alternative oilseed crops for biodiesel production in tropical conditions.

摘要：芸苔属油料作物在工业领域的应用愈发广泛，其中生物柴油方向为重点发展方向。在巴西，评估可作为生物柴油原料的非传统油料作物的产量与产油潜力具有重要现实意义。本研究于巴西东南部的热带气候条件下，历时两年对8份分别隶属于芥菜型油菜（B. juncea）与白菜型油菜（B. rapa）的种质资源的生长性状、产量、含油率及其相关性展开测定。结果显示，两类油菜的种质资源在产量构成因子与含油率上均存在显著差异。其中白菜型油菜成熟最早且含油率最高，而芥菜型油菜的单株角果数、籽粒产量及产油量均为最优。白菜型油菜种质资源开花较早，平均生育周期为97天；而芥菜型油菜的平均成熟天数则为110天。研究人员按各物种的含油率对种质资源进行分组，含油率处于45%~47%区间的种质资源最具应用潜力。芸苔属油料作物的种质资源整体产油量较高，其中芥菜型油菜PI 180266的产油量可达910 kg·ha⁻¹。进一步分析发现，芸苔属油料作物种质资源的含油率与千粒重、角果长度及每角果粒数均呈线性相关。综合两年的含油率与产油表现来看，芸苔属油料作物有望成为热带气候条件下用于生物柴油生产的替代油料作物。