After harvest,cassava(Manihot esculenta Crantz)storage roots undergo rapid postharvest physiological deterioration,producing blue-brown discoloration in the vasculature due to the production of polyphenolics(mainly qu...After harvest,cassava(Manihot esculenta Crantz)storage roots undergo rapid postharvest physiological deterioration,producing blue-brown discoloration in the vasculature due to the production of polyphenolics(mainly quinonesand coumarins)by enzymes such as polyphenol oxidase(PPO).Here,we report the application of hen egg-white lysozyme(HEWL),a natural PPO inhibitor,in transgenic cassava to repress the symptoms of postharvest physiological deterioration.The HEWL-expressing transgenic plants had lower levels of the two main cassava coumarins tested,scopoletin and scopolin,compared with wild type.HEWL-expressing cassava also showed increased tolerance of oxidative stress.Overall,the lysozyme-PPO system proved to be functional in plants for repressing PPO-mediated commercial product browning.展开更多
The species Cajanus cajan L. where pigeonpea is from presents a harvest potential in tropical regions for it is used as human and animal feed, besides being used as green fertilizer. However, the harvest area of this ...The species Cajanus cajan L. where pigeonpea is from presents a harvest potential in tropical regions for it is used as human and animal feed, besides being used as green fertilizer. However, the harvest area of this Fabaceae is still insignificant, due to especially the lack of quality seeds. In this context, it is possible to affirm that drying and store are portrayed as important steps for obtaining superior quality seeds. The aim of this study is to evaluate the physiologic quality of dwarf pigeonpea seeds, with different water content during storage. A factorial scheme 3 × 6 was adopted in the delimitation completely randomized, with four replications. Treatments were constituted by the combination of lots of seeds containing three different water contents (11%, 14% and 16%), submitted to a 10-month storage period, with evaluations every two months (0, 2, 4, 6, 8 and 10). Seeds were stocked in a bag type kraft under normal lab conditions, that is, no control. Physiologic quality of the seeds was evaluated through the following tests: Germination Pattern Test—GPT, first count of germination, accelerated aging and electric conductivity. It can be concluded that pigeonpea with hard seeds containing water content at 11% existing superior physiologic quality throughout the 10-month storage, under no controlled condition, certainly promoted by the less intense breathing from the reserves cumulated in the seed lot. Pigeonpea seeds storage with water content superior to 14% promotes a sharp decrease of physiologic quality, due to an increase in metabolic activity.展开更多
基金supported by the National Key R&D Program of China(2018YFD1000500)China Agriculture Research System(CARS-11)。
文摘After harvest,cassava(Manihot esculenta Crantz)storage roots undergo rapid postharvest physiological deterioration,producing blue-brown discoloration in the vasculature due to the production of polyphenolics(mainly quinonesand coumarins)by enzymes such as polyphenol oxidase(PPO).Here,we report the application of hen egg-white lysozyme(HEWL),a natural PPO inhibitor,in transgenic cassava to repress the symptoms of postharvest physiological deterioration.The HEWL-expressing transgenic plants had lower levels of the two main cassava coumarins tested,scopoletin and scopolin,compared with wild type.HEWL-expressing cassava also showed increased tolerance of oxidative stress.Overall,the lysozyme-PPO system proved to be functional in plants for repressing PPO-mediated commercial product browning.
基金To the Foundation for Support of Higher Education(CAPES)the partial funding of researchThe National Council for Scientific and Technological Development(CNPq)the receive of productivity in research grants to the tree author.
文摘The species Cajanus cajan L. where pigeonpea is from presents a harvest potential in tropical regions for it is used as human and animal feed, besides being used as green fertilizer. However, the harvest area of this Fabaceae is still insignificant, due to especially the lack of quality seeds. In this context, it is possible to affirm that drying and store are portrayed as important steps for obtaining superior quality seeds. The aim of this study is to evaluate the physiologic quality of dwarf pigeonpea seeds, with different water content during storage. A factorial scheme 3 × 6 was adopted in the delimitation completely randomized, with four replications. Treatments were constituted by the combination of lots of seeds containing three different water contents (11%, 14% and 16%), submitted to a 10-month storage period, with evaluations every two months (0, 2, 4, 6, 8 and 10). Seeds were stocked in a bag type kraft under normal lab conditions, that is, no control. Physiologic quality of the seeds was evaluated through the following tests: Germination Pattern Test—GPT, first count of germination, accelerated aging and electric conductivity. It can be concluded that pigeonpea with hard seeds containing water content at 11% existing superior physiologic quality throughout the 10-month storage, under no controlled condition, certainly promoted by the less intense breathing from the reserves cumulated in the seed lot. Pigeonpea seeds storage with water content superior to 14% promotes a sharp decrease of physiologic quality, due to an increase in metabolic activity.
