Bettoni Jean Carlos, Mathew Liya, Pathirana Ranjith, Wiedow Claudia, Hunter Donald A, McLachlan Andrew, Khan Subuhi, Tang Joe, Nadarajan Jayanthi
The New Zealand Institute for Plant and Food Research Limited, Food Industry Science Centre, Palmerston North, New Zealand.
Plant Health and Environment Laboratory, Ministry for Primary Industries, Auckland, New Zealand.
Front Plant Sci. 2022 May 19;13:878733. doi: 10.3389/fpls.2022.878733. eCollection 2022.
Certain viruses dramatically affect yield and quality of potatoes and have proved difficult to eradicate with current approaches. Here, we describe a reliable and efficient virus eradication method that is high throughput and more efficacious at producing virus-free potato plants than current reported methods. Thermotherapy, chemotherapy, and cryotherapy treatments were tested alone and in combination for ability to eradicate single and mixed (PVS), (PVA), and (PVM) infections from three potato cultivars. Chemotherapy treatments were undertaken on shoot segments for four weeks in culture medium supplemented with 100 mg L ribavirin. Thermotherapy on shoot segments was applied for two weeks at 40°C (day) and 28°C (night) with a 16 h photoperiod. Plant vitrification solution 2 (PVS2) and cryotherapy treatments included a shoot tip preculture followed by exposure to PVS2 either without or with liquid nitrogen (LN, cryotherapy) treatment. The virus status of control and recovered plants following therapies was assessed in post-regeneration culture after 3 months and then retested in plants after they had been growing in a greenhouse for a further 3 months. Microtuber production was investigated using virus-free and virus-infected segments. We found that thermotherapy and cryotherapy (60 min PVS2 + LN) used alone were not effective in virus eradication, while chemotherapy was better but with variable efficacy (20-100%). The most effective result (70-100% virus eradication) was obtained by combining chemotherapy with cryotherapy, or by consecutive chemotherapy, combined chemotherapy and thermotherapy, then cryotherapy treatments irrespective of cultivar. Regrowth following the two best virus eradication treatments was similar ranging from 8.6 to 29% across the three cultivars. The importance of virus removal on yield was reflected in "Dunluce" free of PVS having higher numbers of microtubers and in "V500' free of PVS and PVA having a greater proportion of microtubers > 5 mm. Our improved procedure has potential for producing virus-free planting material for the potato industry. It could also underpin the global exchange of virus-free germplasm for conservation and breeding programs.
某些病毒会极大地影响马铃薯的产量和品质，并且事实证明，用目前的方法很难根除这些病毒。在此，我们描述了一种可靠且高效的病毒根除方法，该方法具有高通量，并且在生产无病毒马铃薯植株方面比目前报道的方法更有效。我们单独测试了热处理、化学处理和冷冻处理，并将它们结合起来测试，以评估它们从三个马铃薯品种中根除单一和混合（马铃薯S病毒，PVS）、（马铃薯A病毒，PVA）和（马铃薯M病毒，PVM）感染的能力。化学处理是在添加了100 mg/L利巴韦林的培养基中对茎段进行为期四周的处理。对茎段进行热处理，在40°C（白天）和28°C（夜晚）、16小时光照周期的条件下处理两周。植物玻璃化溶液2（PVS2）和冷冻处理包括茎尖预培养，然后在不进行或进行液氮（LN，冷冻处理）处理的情况下将其暴露于PVS2中。在处理3个月后的再生培养中评估对照植株和处理后恢复的植株的病毒状态，然后在它们在温室中再生长3个月后对植株进行重新测试。使用无病毒和感染病毒的茎段研究微型薯的生产。我们发现单独使用热处理和冷冻处理（60分钟PVS2 + LN）在病毒根除方面无效，而化学处理效果更好但效果不一（20 - 100%）。通过将化学处理与冷冻处理相结合，或者通过连续化学处理、联合化学处理和热处理然后冷冻处理，无论品种如何，都能获得最有效的结果（70 - 100%的病毒根除率）。在三种最好的病毒根除处理后的再生率相似，在三个品种中从8.6%到29%不等。去除病毒对产量的重要性体现在不含PVS的“邓卢斯”品种有更多的微型薯，以及不含PVS和PVA的“V500”品种有更大比例的微型薯大于5毫米。我们改进的方法有潜力为马铃薯产业生产无病毒种植材料。它还可以为全球无病毒种质的交换提供支持，用于种质保存和育种计划。
