Effects of Reproductive Materials on Growth, Corm Yield, and Glucomannan Content in <i>Amorphophallus bulbifer</i>

<i>Amorphophallus bulbifer</i>, known for its high glucomannan content, has extensive applications and significant economic value. However, the effects of different types of propagation materials on the yield and glucomannan content of <i>A. bulbifer</i> have not been thoroughly understood. This study compares the impacts of six propagation materials on the dynamic changes of morphological and physiological characteristics across three growth periods, as well as their effects on yield and the glucomannan content in corms in 2022 and 2023. The results indicated that the yield hierarchy among the six propagation materials was as follows: 2-year-old corms (T1) > 1-year-old corms propagated from bulbils (T3) > 1-year-old corms propagated from seeds (T5) > bulbils (T2) > tissue-cultured seedlings (T6) > seeds (T4). The sizes of the aboveground morphological characteristics (petiole diameter, plant height, and leaf area) were consistently largest in the T1 treatment and smallest in the T4 treatment. Based on 2 years of data, in the new corm formation stage, chlorophyll content was highest in the T5 treatment, exceeding T4 by 49.36%. T1 had the highest soluble sugar content, surpassing T6 by 70.19%, while T2 had the highest soluble protein content, 110.45% higher than T5. In the bulking stage, T5 again had the highest chlorophyll content, 58.96% higher than T6. T6 showed the highest net photosynthetic rate, 24.74% higher than T2. T2 had the highest soluble sugar content, 114.91% more than T6, and T6 had the highest soluble protein content, surpassing T1 by 253.94%. At maturity, T4 had the highest chlorophyll and soluble protein levels, exceeding T3 by 74.80% and 134.71%, respectively. T6 had the highest net photosynthetic rate, 97.18% higher than T2. In summary, the 1-year-old corms propagated from seeds exhibited the highest glucomannan content while having a low weight, making it the optimal propagation material for <i>A. bulbifer</i>.