In the world of table grape cultivation, fruit cracking has long been a thorn in the side of growers, leading to substantial economic losses and reduced marketability. However, a recent study published in the Horticultural Plant Journal, translated from its original Chinese title, offers new insights into the mechanisms behind this persistent challenge, potentially paving the way for innovative solutions in the agritech industry.
Led by Jun Yu, a researcher from the College of Agriculture and Biotechnology at Hunan University of Humanities, Science and Technology, and the Zhengzhou Fruit Research Institute of the Chinese Academy of Agricultural Sciences, the study delves into the role of aquaporins—proteins that facilitate water transport in plants—in grape berry cracking.
The research team conducted a comprehensive two-year investigation, assessing the fruit cracking percentage of 15 table grape (Vitis vinifera L.) varieties. They identified two varieties for further study: the cracking-susceptible ‘Xiangfei’ and the cracking-resistant ‘Zuijinxiang’. By plotting fruit growth curves, they pinpointed the critical phase for fruit cracking incidence between 48 and 53 days after full bloom (DAFB).
During this period, the team found that ‘Xiangfei’ fruit exhibited significantly higher water content and mesocarp cell area compared to ‘Zuijinxiang’. To test the role of aquaporins, they applied aquaporin inhibitors (nano-silver) to ‘Xiangfei’ berries, which reduced fruit water uptake and cracking percentage. Conversely, applying aquaporin activators (forskolin) to ‘Zuijinxiang’ berries increased both fruit water uptake and cracking percentage.
The study also analyzed the expression of six genes associated with plasma membrane intrinsic proteins (PIPs) synthesis. Only the expression level of VvPIP1;1 was higher in ‘Zuijinxiang’ than in ‘Xiangfei’ during the fruit cracking period. This finding suggests that VvPIP1;1 plays a pivotal role in controlling grape berry cracking.
To further validate their findings, the researchers conducted transgenic overexpression of VvPIP1;1 in tomato, which resulted in increased fruit water content, enlarged mesocarp cell size, and enhanced fruit cracking percentage.
“This study provides a deeper understanding of the molecular mechanisms underlying fruit cracking in table grapes,” said Jun Yu. “By targeting VvPIP1;1, we may be able to develop new strategies to control this disorder and improve the marketability of table grapes.”
The implications of this research extend beyond the table grape industry. Understanding the role of aquaporins in fruit cracking can inform breeding programs and genetic engineering efforts aimed at enhancing fruit quality and reducing postharvest losses in various crops. This could lead to more resilient and marketable produce, ultimately benefiting growers, distributors, and consumers alike.
As the agritech industry continues to evolve, insights from this study could inspire innovative solutions for other crops facing similar challenges. By harnessing the power of genetic research and biotechnology, the future of agriculture looks promising, with the potential to minimize waste and maximize productivity in the global food supply chain.