Abstract Currently, stevia (Stevia rebaudiana Bertoni) seeds are available to growers from many sources, but the origin of these populations is often unknown. Since stevia is a natural outcrosser, populations are heterozygous and heterogeneous. We were interested to characterize germplasm from 16 sources of stevia seeds for traits including yield, glycosides, and plant morphology, and then identify trait correlations. The cultigens evaluated were obtained from garden seed companies and commercial sources, and the trials were conducted for two years at two field locations. To quantify plant morphological traits, objective measurements were collected at two intervals to determine stem height, branching width, and leaf area. In addition, we screened for lodging and disease resistance, and yield before flowering stage. The cultigens tested were highly variable for yield and steviol glycosides, suggesting that a diverse genetic base is found among the population which is readily available to growers and breeders. High-yielding cultigens for biomass and glycoside concentration were identified. Cultigens with the highest yield and stability over years were seed-derived progeny from ‘Katupyry’, sourced from Stevia Store, and represent genetics useful in breeding for increased biomass. Cultigens with the highest glycoside level were NC-1003 and NC-1022, seed grown from Seed Savers, and could be used to improve desirable glycosides. This study highlights readily available seed cultigens that can be used to develop elite breeding populations.

中文翻译：

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北卡罗来纳州 16 种甜叶菊种子栽培种的糖苷和产量性能

摘要 目前，种植者可以从许多来源获得甜菊 (Stevia rebaudiana Bertoni) 种子，但这些种群的起源通常是未知的。由于甜菊是一种天然的异交菌，种群是杂合的和异质的。我们有兴趣表征来自 16 个甜菊种子来源的种质，包括产量、糖苷和植物形态等性状，然后确定性状相关性。评估的栽培种来自园艺种子公司和商业来源，试验在两个田间地点进行了两年。为了量化植物形态特征，以两个间隔收集客观测量值以确定茎高、分枝宽度和叶面积。此外，我们在开花前筛选了抗倒伏性和抗病性以及产量。测试的栽培种在产量和甜菊糖苷方面变化很大，这表明在种群中发现了多种遗传基础，种植者和育种者很容易获得。鉴定了生物量和糖苷浓度的高产栽培种。多年来产量和稳定性最高的栽培种是来自“Katupyry”的种子衍生后代，来自甜叶菊商店，代表了可用于增加生物量育种的遗传学。糖苷含量最高的栽培种是 NC-1003 和 NC-1022，它们是从 Seed Savers 种植的种子，可用于改进所需的糖苷。本研究重点介绍了可用于培育优良育种种群的现成种子栽培种。表明在种群中发现了多样化的遗传基础，种植者和育种者很容易获得。鉴定了生物量和糖苷浓度的高产栽培种。多年来产量和稳定性最高的栽培种是来自“Katupyry”的种子衍生后代，来自甜叶菊商店，代表了可用于增加生物量育种的遗传学。糖苷含量最高的栽培种是 NC-1003 和 NC-1022，它们是从 Seed Savers 种植的种子，可用于改进所需的糖苷。本研究重点介绍了可用于培育优良育种种群的现成种子栽培种。表明在种群中发现了多样化的遗传基础，种植者和育种者很容易获得。鉴定了生物量和糖苷浓度的高产栽培种。多年来产量和稳定性最高的栽培种是来自“Katupyry”的种子衍生后代，来自甜叶菊商店，代表了可用于增加生物量育种的遗传学。糖苷含量最高的栽培种是 NC-1003 和 NC-1022，它们是从 Seed Savers 种植的种子，可用于改进所需的糖苷。本研究重点介绍了可用于培育优良育种种群的现成种子栽培种。多年来产量和稳定性最高的栽培种是来自“Katupyry”的种子衍生后代，来自甜叶菊商店，代表了可用于增加生物量育种的遗传学。糖苷含量最高的栽培种是 NC-1003 和 NC-1022，它们是从 Seed Savers 种植的种子，可用于改进所需的糖苷。本研究重点介绍了可用于培育优良育种种群的现成种子栽培种。多年来产量和稳定性最高的栽培种是来自“Katupyry”的种子衍生后代，来自甜叶菊商店，代表了可用于增加生物量育种的遗传学。糖苷含量最高的栽培种是 NC-1003 和 NC-1022，它们是从 Seed Savers 种植的种子，可用于改进所需的糖苷。本研究重点介绍了可用于培育优良育种种群的现成种子栽培种。