National Key Laboratory of Ecological Security and Sustainable Development in Arid Region, State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, Xinjiang, China.
Key Laboratory of Biodiversity Conservation and Application in Arid Lands Xinjiang, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, Xinjiang, China.
Plant Cell Environ. 2024 Dec;47(12):5280-5296. doi: 10.1111/pce.15100. Epub 2024 Aug 26.
The impact of nitrogen (N) and phosphorus (P) on the physiological and biochemical processes crucial for tree seedling growth is substantial. Although the study of plant hydraulic traits in response to N and P is growing, comprehensive research on their combined effects remains limited. Malus sieversii, a key ancestral species of modern apples and a dominant species in Xinjiang's Tianshan wild fruit forest, is witnessing a decline due to climate change, pests and diseases, compounded by challenges in seedling regeneration. Addressing this, a 4-year study was conducted to determine the optimal fertilisation method for it. The experiment explored varying levels of N (N10, N20 and N40) and P (P2, P4 and P8), and their combined effects (N20Px: N20P2, N20P4, N20P8; NxP4: N10P4, N20P4 and N40P4), assessing their impact on gas exchange, hydraulic traits, and the interplay among functional traits in Tianshan Mountains' M. sieversii seedlings. Our study revealed that All N-inclusive fertilisers slightly promoted the net photosynthetic rate. N10 significantly increasing leaf hydraulic conductivity. All P-inclusive fertilisers adversely affected hydraulic conductivity. P8, N20P4 and N20P8 notably increased seedlings' vulnerability to embolism. Seedlings can adaptively adjust multiple functional traits in response to nutrient changes. The research suggests N10 and N20 as the most effective fertilisation treatments for M. sieversii seedlings in this region, while fertilisation involving phosphorus is less suitable. This study contributes valuable insights into the specific nutrient needs of it, vital for conservation and cultivation efforts in the Tianshan region.
氮（N）和磷（P）对树木幼苗生长至关重要的生理和生化过程有重大影响。尽管对植物水力特性对 N 和 P 的响应的研究正在增加，但对它们综合影响的综合研究仍然有限。绵苹果是现代苹果的主要祖先种之一，也是新疆天山野生果林的优势种，由于气候变化、病虫害以及幼苗再生的挑战，其数量正在减少。为了解决这个问题，进行了一项为期 4 年的研究，以确定最适合它的施肥方法。该实验探讨了不同水平的 N（N10、N20 和 N40）和 P（P2、P4 和 P8），以及它们的组合效应（N20Px：N20P2、N20P4 和 N20P8；NxP4：N10P4、N20P4 和 N40P4），评估它们对天山绵苹果幼苗气体交换、水力特性以及功能特性之间相互作用的影响。我们的研究表明，所有包含 N 的肥料都轻微促进了净光合速率。N10 显著增加了叶片水力导率。所有包含 P 的肥料都对水力导率产生了不利影响。P8、N20P4 和 N20P8 显著增加了幼苗对栓塞的脆弱性。幼苗可以自适应地调整多种功能特性以响应养分变化。研究表明，在该地区，N10 和 N20 是最适合绵苹果幼苗的施肥处理，而涉及磷的施肥则不太合适。这项研究为保护和栽培天山地区的绵苹果提供了有价值的见解，了解其特定的营养需求至关重要。
