Effects of Low Temperature Stress on Source–Sink Organs in Wheat and Phosphorus Mitigation Strategies

Abstract

The 21st century presents many challenges to mankind, including climate change, fast growing human population, and serious concerns over food security. Wheat is a leading cereal crop that largely fulfills the global food needs. Low temperature stress accompanied by nutrient-starved soils is badly disrupting the source–sink relationship of wheat, thus causing an acute decline in final yield and deteriorating the grain quality. This review paper aimed to understand how low temperature stress affects wheat source–sink organs (i.e., leaves, roots, and spikes) and how phosphorus application reliefs in alleviating its harmful consequences. Also, we discussed mitigation strategies to enhance wheat capacity to adapt to varying temperature extremes and made rational recommendations based on modern agronomic and breeding approaches. Therefore, this study is likely to establish a solid foundation for improving the tolerance to low temperature stress and to improve its phosphorus utilization efficiency in wheat.

Optimized Phosphorus Application Alleviated Adverse Effects of Short-Term Low-Temperature Stress in Winter Wheat by Enhancing Photosynthesis and Improved Accumulation and Partitioning of Dry Matter

“…Thus, it is suggested that the low-temperature effect on wheat dry matter accumulation depended on not only the low-temperature level and duration but also the wheat growth stages when the low-temperature event occurred [50]. Due to dehydration and poor photosynthesis caused by low-temperature stress, dry matter accumulation of aboveground organs and transportation to grains significantly decreased [6]. Ma et al [51] also found that stress reduced dry matter assimilation and translocation capacity in the post-flowering stages.…”

“…It is established that low-temperature stress eventually reduces yield by reducing photosynthesis and dry matter accumulation and transportation [6,49]. Previous studies mostly focused on the damage of low-temperature stress during the reproductive stage [54,55].…”

“…As spring approaches, wheat's sensitivity to cold and the risk of low-temperature stress also increase [5]. Recently, low-temperature stress has caused considerable losses to wheat producers [6,7].…”

“…This severe reduction is due to the low-temperature induced excessive accumulation of reactive oxygen species, which leads to pollen abortion, anther inactivation and decreased GNPS [11,19]. Moreover, under low-temperature stress, an imbalanced source-sink relationship reduces assimilates' accumulation and transportation to spike, resulting in a significant decrease in GNPS and TGW [6].…”

“…Previously, plenty of studies showed that phosphorus could improve the stress resistance of horticultural crops and field crops [22,23]. Phosphorus application effectively improves the soil-plant nutrition relationship, ensures source-sink balance, strengthens membrane stability and alleviates dehydration and oxidation stress caused by abiotic stress such as low-temperature [6,24]. Under water deficit stress, the positive effects of phosphorus were reflected in improving the growth and phenolic compounds in the root [25].…”